@ Documentation/driver-api/libata.rst:121 @ PIO data read/write All bmdma-style drivers must implement this hook. This is the low-level operation that actually copies the data bytes during a PIO data transfer. Typically the driver will choose one of -:c:func:`ata_sff_data_xfer_noirq`, :c:func:`ata_sff_data_xfer`, or -:c:func:`ata_sff_data_xfer32`. +:c:func:`ata_sff_data_xfer`, or :c:func:`ata_sff_data_xfer32`. ATA command execute ~~~~~~~~~~~~~~~~~~~ @ Documentation/trace/events.txt:520 @ triggers (you have to use '!' for each one added.) totals derived from one or more trace event format fields and/or event counts (hitcount). - The format of a hist trigger is as follows: - - hist:keys=<field1[,field2,...]>[:values=<field1[,field2,...]>] - [:sort=<field1[,field2,...]>][:size=#entries][:pause][:continue] - [:clear][:name=histname1] [if <filter>] - - When a matching event is hit, an entry is added to a hash table - using the key(s) and value(s) named. Keys and values correspond to - fields in the event's format description. Values must correspond to - numeric fields - on an event hit, the value(s) will be added to a - sum kept for that field. The special string 'hitcount' can be used - in place of an explicit value field - this is simply a count of - event hits. If 'values' isn't specified, an implicit 'hitcount' - value will be automatically created and used as the only value. - Keys can be any field, or the special string 'stacktrace', which - will use the event's kernel stacktrace as the key. The keywords - 'keys' or 'key' can be used to specify keys, and the keywords - 'values', 'vals', or 'val' can be used to specify values. Compound - keys consisting of up to two fields can be specified by the 'keys' - keyword. Hashing a compound key produces a unique entry in the - table for each unique combination of component keys, and can be - useful for providing more fine-grained summaries of event data. - Additionally, sort keys consisting of up to two fields can be - specified by the 'sort' keyword. If more than one field is - specified, the result will be a 'sort within a sort': the first key - is taken to be the primary sort key and the second the secondary - key. If a hist trigger is given a name using the 'name' parameter, - its histogram data will be shared with other triggers of the same - name, and trigger hits will update this common data. Only triggers - with 'compatible' fields can be combined in this way; triggers are - 'compatible' if the fields named in the trigger share the same - number and type of fields and those fields also have the same names. - Note that any two events always share the compatible 'hitcount' and - 'stacktrace' fields and can therefore be combined using those - fields, however pointless that may be. - - 'hist' triggers add a 'hist' file to each event's subdirectory. - Reading the 'hist' file for the event will dump the hash table in - its entirety to stdout. If there are multiple hist triggers - attached to an event, there will be a table for each trigger in the - output. The table displayed for a named trigger will be the same as - any other instance having the same name. Each printed hash table - entry is a simple list of the keys and values comprising the entry; - keys are printed first and are delineated by curly braces, and are - followed by the set of value fields for the entry. By default, - numeric fields are displayed as base-10 integers. This can be - modified by appending any of the following modifiers to the field - name: - - .hex display a number as a hex value - .sym display an address as a symbol - .sym-offset display an address as a symbol and offset - .syscall display a syscall id as a system call name - .execname display a common_pid as a program name - - Note that in general the semantics of a given field aren't - interpreted when applying a modifier to it, but there are some - restrictions to be aware of in this regard: - - - only the 'hex' modifier can be used for values (because values - are essentially sums, and the other modifiers don't make sense - in that context). - - the 'execname' modifier can only be used on a 'common_pid'. The - reason for this is that the execname is simply the 'comm' value - saved for the 'current' process when an event was triggered, - which is the same as the common_pid value saved by the event - tracing code. Trying to apply that comm value to other pid - values wouldn't be correct, and typically events that care save - pid-specific comm fields in the event itself. - - A typical usage scenario would be the following to enable a hist - trigger, read its current contents, and then turn it off: - - # echo 'hist:keys=skbaddr.hex:vals=len' > \ - /sys/kernel/debug/tracing/events/net/netif_rx/trigger - - # cat /sys/kernel/debug/tracing/events/net/netif_rx/hist - - # echo '!hist:keys=skbaddr.hex:vals=len' > \ - /sys/kernel/debug/tracing/events/net/netif_rx/trigger - - The trigger file itself can be read to show the details of the - currently attached hist trigger. This information is also displayed - at the top of the 'hist' file when read. - - By default, the size of the hash table is 2048 entries. The 'size' - parameter can be used to specify more or fewer than that. The units - are in terms of hashtable entries - if a run uses more entries than - specified, the results will show the number of 'drops', the number - of hits that were ignored. The size should be a power of 2 between - 128 and 131072 (any non- power-of-2 number specified will be rounded - up). - - The 'sort' parameter can be used to specify a value field to sort - on. The default if unspecified is 'hitcount' and the default sort - order is 'ascending'. To sort in the opposite direction, append - .descending' to the sort key. - - The 'pause' parameter can be used to pause an existing hist trigger - or to start a hist trigger but not log any events until told to do - so. 'continue' or 'cont' can be used to start or restart a paused - hist trigger. - - The 'clear' parameter will clear the contents of a running hist - trigger and leave its current paused/active state. - - Note that the 'pause', 'cont', and 'clear' parameters should be - applied using 'append' shell operator ('>>') if applied to an - existing trigger, rather than via the '>' operator, which will cause - the trigger to be removed through truncation. - -- enable_hist/disable_hist - - The enable_hist and disable_hist triggers can be used to have one - event conditionally start and stop another event's already-attached - hist trigger. Any number of enable_hist and disable_hist triggers - can be attached to a given event, allowing that event to kick off - and stop aggregations on a host of other events. - - The format is very similar to the enable/disable_event triggers: - - enable_hist:<system>:<event>[:count] - disable_hist:<system>:<event>[:count] - - Instead of enabling or disabling the tracing of the target event - into the trace buffer as the enable/disable_event triggers do, the - enable/disable_hist triggers enable or disable the aggregation of - the target event into a hash table. - - A typical usage scenario for the enable_hist/disable_hist triggers - would be to first set up a paused hist trigger on some event, - followed by an enable_hist/disable_hist pair that turns the hist - aggregation on and off when conditions of interest are hit: - - # echo 'hist:keys=skbaddr.hex:vals=len:pause' > \ - /sys/kernel/debug/tracing/events/net/netif_receive_skb/trigger - - # echo 'enable_hist:net:netif_receive_skb if filename==/usr/bin/wget' > \ - /sys/kernel/debug/tracing/events/sched/sched_process_exec/trigger - - # echo 'disable_hist:net:netif_receive_skb if comm==wget' > \ - /sys/kernel/debug/tracing/events/sched/sched_process_exit/trigger - - The above sets up an initially paused hist trigger which is unpaused - and starts aggregating events when a given program is executed, and - which stops aggregating when the process exits and the hist trigger - is paused again. - - The examples below provide a more concrete illustration of the - concepts and typical usage patterns discussed above. - - -6.2 'hist' trigger examples ---------------------------- - - The first set of examples creates aggregations using the kmalloc - event. The fields that can be used for the hist trigger are listed - in the kmalloc event's format file: - - # cat /sys/kernel/debug/tracing/events/kmem/kmalloc/format - name: kmalloc - ID: 374 - format: - field:unsigned short common_type; offset:0; size:2; signed:0; - field:unsigned char common_flags; offset:2; size:1; signed:0; - field:unsigned char common_preempt_count; offset:3; size:1; signed:0; - field:int common_pid; offset:4; size:4; signed:1; - - field:unsigned long call_site; offset:8; size:8; signed:0; - field:const void * ptr; offset:16; size:8; signed:0; - field:size_t bytes_req; offset:24; size:8; signed:0; - field:size_t bytes_alloc; offset:32; size:8; signed:0; - field:gfp_t gfp_flags; offset:40; size:4; signed:0; - - We'll start by creating a hist trigger that generates a simple table - that lists the total number of bytes requested for each function in - the kernel that made one or more calls to kmalloc: - - # echo 'hist:key=call_site:val=bytes_req' > \ - /sys/kernel/debug/tracing/events/kmem/kmalloc/trigger - - This tells the tracing system to create a 'hist' trigger using the - call_site field of the kmalloc event as the key for the table, which - just means that each unique call_site address will have an entry - created for it in the table. The 'val=bytes_req' parameter tells - the hist trigger that for each unique entry (call_site) in the - table, it should keep a running total of the number of bytes - requested by that call_site. - - We'll let it run for awhile and then dump the contents of the 'hist' - file in the kmalloc event's subdirectory (for readability, a number - of entries have been omitted): - - # cat /sys/kernel/debug/tracing/events/kmem/kmalloc/hist - # trigger info: hist:keys=call_site:vals=bytes_req:sort=hitcount:size=2048 [active] - - { call_site: 18446744072106379007 } hitcount: 1 bytes_req: 176 - { call_site: 18446744071579557049 } hitcount: 1 bytes_req: 1024 - { call_site: 18446744071580608289 } hitcount: 1 bytes_req: 16384 - { call_site: 18446744071581827654 } hitcount: 1 bytes_req: 24 - { call_site: 18446744071580700980 } hitcount: 1 bytes_req: 8 - { call_site: 18446744071579359876 } hitcount: 1 bytes_req: 152 - { call_site: 18446744071580795365 } hitcount: 3 bytes_req: 144 - { call_site: 18446744071581303129 } hitcount: 3 bytes_req: 144 - { call_site: 18446744071580713234 } hitcount: 4 bytes_req: 2560 - { call_site: 18446744071580933750 } hitcount: 4 bytes_req: 736 - . - . - . - { call_site: 18446744072106047046 } hitcount: 69 bytes_req: 5576 - { call_site: 18446744071582116407 } hitcount: 73 bytes_req: 2336 - { call_site: 18446744072106054684 } hitcount: 136 bytes_req: 140504 - { call_site: 18446744072106224230 } hitcount: 136 bytes_req: 19584 - { call_site: 18446744072106078074 } hitcount: 153 bytes_req: 2448 - { call_site: 18446744072106062406 } hitcount: 153 bytes_req: 36720 - { call_site: 18446744071582507929 } hitcount: 153 bytes_req: 37088 - { call_site: 18446744072102520590 } hitcount: 273 bytes_req: 10920 - { call_site: 18446744071582143559 } hitcount: 358 bytes_req: 716 - { call_site: 18446744072106465852 } hitcount: 417 bytes_req: 56712 - { call_site: 18446744072102523378 } hitcount: 485 bytes_req: 27160 - { call_site: 18446744072099568646 } hitcount: 1676 bytes_req: 33520 - - Totals: - Hits: 4610 - Entries: 45 - Dropped: 0 - - The output displays a line for each entry, beginning with the key - specified in the trigger, followed by the value(s) also specified in - the trigger. At the beginning of the output is a line that displays - the trigger info, which can also be displayed by reading the - 'trigger' file: - - # cat /sys/kernel/debug/tracing/events/kmem/kmalloc/trigger - hist:keys=call_site:vals=bytes_req:sort=hitcount:size=2048 [active] - - At the end of the output are a few lines that display the overall - totals for the run. The 'Hits' field shows the total number of - times the event trigger was hit, the 'Entries' field shows the total - number of used entries in the hash table, and the 'Dropped' field - shows the number of hits that were dropped because the number of - used entries for the run exceeded the maximum number of entries - allowed for the table (normally 0, but if not a hint that you may - want to increase the size of the table using the 'size' parameter). - - Notice in the above output that there's an extra field, 'hitcount', - which wasn't specified in the trigger. Also notice that in the - trigger info output, there's a parameter, 'sort=hitcount', which - wasn't specified in the trigger either. The reason for that is that - every trigger implicitly keeps a count of the total number of hits - attributed to a given entry, called the 'hitcount'. That hitcount - information is explicitly displayed in the output, and in the - absence of a user-specified sort parameter, is used as the default - sort field. - - The value 'hitcount' can be used in place of an explicit value in - the 'values' parameter if you don't really need to have any - particular field summed and are mainly interested in hit - frequencies. - - To turn the hist trigger off, simply call up the trigger in the - command history and re-execute it with a '!' prepended: - - # echo '!hist:key=call_site:val=bytes_req' > \ - /sys/kernel/debug/tracing/events/kmem/kmalloc/trigger - - Finally, notice that the call_site as displayed in the output above - isn't really very useful. It's an address, but normally addresses - are displayed in hex. To have a numeric field displayed as a hex - value, simply append '.hex' to the field name in the trigger: - - # echo 'hist:key=call_site.hex:val=bytes_req' > \ - /sys/kernel/debug/tracing/events/kmem/kmalloc/trigger - - # cat /sys/kernel/debug/tracing/events/kmem/kmalloc/hist - # trigger info: hist:keys=call_site.hex:vals=bytes_req:sort=hitcount:size=2048 [active] - - { call_site: ffffffffa026b291 } hitcount: 1 bytes_req: 433 - { call_site: ffffffffa07186ff } hitcount: 1 bytes_req: 176 - { call_site: ffffffff811ae721 } hitcount: 1 bytes_req: 16384 - { call_site: ffffffff811c5134 } hitcount: 1 bytes_req: 8 - { call_site: ffffffffa04a9ebb } hitcount: 1 bytes_req: 511 - { call_site: ffffffff8122e0a6 } hitcount: 1 bytes_req: 12 - { call_site: ffffffff8107da84 } hitcount: 1 bytes_req: 152 - { call_site: ffffffff812d8246 } hitcount: 1 bytes_req: 24 - { call_site: ffffffff811dc1e5 } hitcount: 3 bytes_req: 144 - { call_site: ffffffffa02515e8 } hitcount: 3 bytes_req: 648 - { call_site: ffffffff81258159 } hitcount: 3 bytes_req: 144 - { call_site: ffffffff811c80f4 } hitcount: 4 bytes_req: 544 - . - . - . - { call_site: ffffffffa06c7646 } hitcount: 106 bytes_req: 8024 - { call_site: ffffffffa06cb246 } hitcount: 132 bytes_req: 31680 - { call_site: ffffffffa06cef7a } hitcount: 132 bytes_req: 2112 - { call_site: ffffffff8137e399 } hitcount: 132 bytes_req: 23232 - { call_site: ffffffffa06c941c } hitcount: 185 bytes_req: 171360 - { call_site: ffffffffa06f2a66 } hitcount: 185 bytes_req: 26640 - { call_site: ffffffffa036a70e } hitcount: 265 bytes_req: 10600 - { call_site: ffffffff81325447 } hitcount: 292 bytes_req: 584 - { call_site: ffffffffa072da3c } hitcount: 446 bytes_req: 60656 - { call_site: ffffffffa036b1f2 } hitcount: 526 bytes_req: 29456 - { call_site: ffffffffa0099c06 } hitcount: 1780 bytes_req: 35600 - - Totals: - Hits: 4775 - Entries: 46 - Dropped: 0 - - Even that's only marginally more useful - while hex values do look - more like addresses, what users are typically more interested in - when looking at text addresses are the corresponding symbols - instead. To have an address displayed as symbolic value instead, - simply append '.sym' or '.sym-offset' to the field name in the - trigger: - - # echo 'hist:key=call_site.sym:val=bytes_req' > \ - /sys/kernel/debug/tracing/events/kmem/kmalloc/trigger - - # cat /sys/kernel/debug/tracing/events/kmem/kmalloc/hist - # trigger info: hist:keys=call_site.sym:vals=bytes_req:sort=hitcount:size=2048 [active] - - { call_site: [ffffffff810adcb9] syslog_print_all } hitcount: 1 bytes_req: 1024 - { call_site: [ffffffff8154bc62] usb_control_msg } hitcount: 1 bytes_req: 8 - { call_site: [ffffffffa00bf6fe] hidraw_send_report [hid] } hitcount: 1 bytes_req: 7 - { call_site: [ffffffff8154acbe] usb_alloc_urb } hitcount: 1 bytes_req: 192 - { call_site: [ffffffffa00bf1ca] hidraw_report_event [hid] } hitcount: 1 bytes_req: 7 - { call_site: [ffffffff811e3a25] __seq_open_private } hitcount: 1 bytes_req: 40 - { call_site: [ffffffff8109524a] alloc_fair_sched_group } hitcount: 2 bytes_req: 128 - { call_site: [ffffffff811febd5] fsnotify_alloc_group } hitcount: 2 bytes_req: 528 - { call_site: [ffffffff81440f58] __tty_buffer_request_room } hitcount: 2 bytes_req: 2624 - { call_site: [ffffffff81200ba6] inotify_new_group } hitcount: 2 bytes_req: 96 - { call_site: [ffffffffa05e19af] ieee80211_start_tx_ba_session [mac80211] } hitcount: 2 bytes_req: 464 - { call_site: [ffffffff81672406] tcp_get_metrics } hitcount: 2 bytes_req: 304 - { call_site: [ffffffff81097ec2] alloc_rt_sched_group } hitcount: 2 bytes_req: 128 - { call_site: [ffffffff81089b05] sched_create_group } hitcount: 2 bytes_req: 1424 - . - . - . - { call_site: [ffffffffa04a580c] intel_crtc_page_flip [i915] } hitcount: 1185 bytes_req: 123240 - { call_site: [ffffffffa0287592] drm_mode_page_flip_ioctl [drm] } hitcount: 1185 bytes_req: 104280 - { call_site: [ffffffffa04c4a3c] intel_plane_duplicate_state [i915] } hitcount: 1402 bytes_req: 190672 - { call_site: [ffffffff812891ca] ext4_find_extent } hitcount: 1518 bytes_req: 146208 - { call_site: [ffffffffa029070e] drm_vma_node_allow [drm] } hitcount: 1746 bytes_req: 69840 - { call_site: [ffffffffa045e7c4] i915_gem_do_execbuffer.isra.23 [i915] } hitcount: 2021 bytes_req: 792312 - { call_site: [ffffffffa02911f2] drm_modeset_lock_crtc [drm] } hitcount: 2592 bytes_req: 145152 - { call_site: [ffffffffa0489a66] intel_ring_begin [i915] } hitcount: 2629 bytes_req: 378576 - { call_site: [ffffffffa046041c] i915_gem_execbuffer2 [i915] } hitcount: 2629 bytes_req: 3783248 - { call_site: [ffffffff81325607] apparmor_file_alloc_security } hitcount: 5192 bytes_req: 10384 - { call_site: [ffffffffa00b7c06] hid_report_raw_event [hid] } hitcount: 5529 bytes_req: 110584 - { call_site: [ffffffff8131ebf7] aa_alloc_task_context } hitcount: 21943 bytes_req: 702176 - { call_site: [ffffffff8125847d] ext4_htree_store_dirent } hitcount: 55759 bytes_req: 5074265 - - Totals: - Hits: 109928 - Entries: 71 - Dropped: 0 - - Because the default sort key above is 'hitcount', the above shows a - the list of call_sites by increasing hitcount, so that at the bottom - we see the functions that made the most kmalloc calls during the - run. If instead we we wanted to see the top kmalloc callers in - terms of the number of bytes requested rather than the number of - calls, and we wanted the top caller to appear at the top, we can use - the 'sort' parameter, along with the 'descending' modifier: - - # echo 'hist:key=call_site.sym:val=bytes_req:sort=bytes_req.descending' > \ - /sys/kernel/debug/tracing/events/kmem/kmalloc/trigger - - # cat /sys/kernel/debug/tracing/events/kmem/kmalloc/hist - # trigger info: hist:keys=call_site.sym:vals=bytes_req:sort=bytes_req.descending:size=2048 [active] - - { call_site: [ffffffffa046041c] i915_gem_execbuffer2 [i915] } hitcount: 2186 bytes_req: 3397464 - { call_site: [ffffffffa045e7c4] i915_gem_do_execbuffer.isra.23 [i915] } hitcount: 1790 bytes_req: 712176 - { call_site: [ffffffff8125847d] ext4_htree_store_dirent } hitcount: 8132 bytes_req: 513135 - { call_site: [ffffffff811e2a1b] seq_buf_alloc } hitcount: 106 bytes_req: 440128 - { call_site: [ffffffffa0489a66] intel_ring_begin [i915] } hitcount: 2186 bytes_req: 314784 - { call_site: [ffffffff812891ca] ext4_find_extent } hitcount: 2174 bytes_req: 208992 - { call_site: [ffffffff811ae8e1] __kmalloc } hitcount: 8 bytes_req: 131072 - { call_site: [ffffffffa04c4a3c] intel_plane_duplicate_state [i915] } hitcount: 859 bytes_req: 116824 - { call_site: [ffffffffa02911f2] drm_modeset_lock_crtc [drm] } hitcount: 1834 bytes_req: 102704 - { call_site: [ffffffffa04a580c] intel_crtc_page_flip [i915] } hitcount: 972 bytes_req: 101088 - { call_site: [ffffffffa0287592] drm_mode_page_flip_ioctl [drm] } hitcount: 972 bytes_req: 85536 - { call_site: [ffffffffa00b7c06] hid_report_raw_event [hid] } hitcount: 3333 bytes_req: 66664 - { call_site: [ffffffff8137e559] sg_kmalloc } hitcount: 209 bytes_req: 61632 - . - . - . - { call_site: [ffffffff81095225] alloc_fair_sched_group } hitcount: 2 bytes_req: 128 - { call_site: [ffffffff81097ec2] alloc_rt_sched_group } hitcount: 2 bytes_req: 128 - { call_site: [ffffffff812d8406] copy_semundo } hitcount: 2 bytes_req: 48 - { call_site: [ffffffff81200ba6] inotify_new_group } hitcount: 1 bytes_req: 48 - { call_site: [ffffffffa027121a] drm_getmagic [drm] } hitcount: 1 bytes_req: 48 - { call_site: [ffffffff811e3a25] __seq_open_private } hitcount: 1 bytes_req: 40 - { call_site: [ffffffff811c52f4] bprm_change_interp } hitcount: 2 bytes_req: 16 - { call_site: [ffffffff8154bc62] usb_control_msg } hitcount: 1 bytes_req: 8 - { call_site: [ffffffffa00bf1ca] hidraw_report_event [hid] } hitcount: 1 bytes_req: 7 - { call_site: [ffffffffa00bf6fe] hidraw_send_report [hid] } hitcount: 1 bytes_req: 7 - - Totals: - Hits: 32133 - Entries: 81 - Dropped: 0 - - To display the offset and size information in addition to the symbol - name, just use 'sym-offset' instead: - - # echo 'hist:key=call_site.sym-offset:val=bytes_req:sort=bytes_req.descending' > \ - /sys/kernel/debug/tracing/events/kmem/kmalloc/trigger - - # cat /sys/kernel/debug/tracing/events/kmem/kmalloc/hist - # trigger info: hist:keys=call_site.sym-offset:vals=bytes_req:sort=bytes_req.descending:size=2048 [active] - - { call_site: [ffffffffa046041c] i915_gem_execbuffer2+0x6c/0x2c0 [i915] } hitcount: 4569 bytes_req: 3163720 - { call_site: [ffffffffa0489a66] intel_ring_begin+0xc6/0x1f0 [i915] } hitcount: 4569 bytes_req: 657936 - { call_site: [ffffffffa045e7c4] i915_gem_do_execbuffer.isra.23+0x694/0x1020 [i915] } hitcount: 1519 bytes_req: 472936 - { call_site: [ffffffffa045e646] i915_gem_do_execbuffer.isra.23+0x516/0x1020 [i915] } hitcount: 3050 bytes_req: 211832 - { call_site: [ffffffff811e2a1b] seq_buf_alloc+0x1b/0x50 } hitcount: 34 bytes_req: 148384 - { call_site: [ffffffffa04a580c] intel_crtc_page_flip+0xbc/0x870 [i915] } hitcount: 1385 bytes_req: 144040 - { call_site: [ffffffff811ae8e1] __kmalloc+0x191/0x1b0 } hitcount: 8 bytes_req: 131072 - { call_site: [ffffffffa0287592] drm_mode_page_flip_ioctl+0x282/0x360 [drm] } hitcount: 1385 bytes_req: 121880 - { call_site: [ffffffffa02911f2] drm_modeset_lock_crtc+0x32/0x100 [drm] } hitcount: 1848 bytes_req: 103488 - { call_site: [ffffffffa04c4a3c] intel_plane_duplicate_state+0x2c/0xa0 [i915] } hitcount: 461 bytes_req: 62696 - { call_site: [ffffffffa029070e] drm_vma_node_allow+0x2e/0xd0 [drm] } hitcount: 1541 bytes_req: 61640 - { call_site: [ffffffff815f8d7b] sk_prot_alloc+0xcb/0x1b0 } hitcount: 57 bytes_req: 57456 - . - . - . - { call_site: [ffffffff8109524a] alloc_fair_sched_group+0x5a/0x1a0 } hitcount: 2 bytes_req: 128 - { call_site: [ffffffffa027b921] drm_vm_open_locked+0x31/0xa0 [drm] } hitcount: 3 bytes_req: 96 - { call_site: [ffffffff8122e266] proc_self_follow_link+0x76/0xb0 } hitcount: 8 bytes_req: 96 - { call_site: [ffffffff81213e80] load_elf_binary+0x240/0x1650 } hitcount: 3 bytes_req: 84 - { call_site: [ffffffff8154bc62] usb_control_msg+0x42/0x110 } hitcount: 1 bytes_req: 8 - { call_site: [ffffffffa00bf6fe] hidraw_send_report+0x7e/0x1a0 [hid] } hitcount: 1 bytes_req: 7 - { call_site: [ffffffffa00bf1ca] hidraw_report_event+0x8a/0x120 [hid] } hitcount: 1 bytes_req: 7 - - Totals: - Hits: 26098 - Entries: 64 - Dropped: 0 - - We can also add multiple fields to the 'values' parameter. For - example, we might want to see the total number of bytes allocated - alongside bytes requested, and display the result sorted by bytes - allocated in a descending order: - - # echo 'hist:keys=call_site.sym:values=bytes_req,bytes_alloc:sort=bytes_alloc.descending' > \ - /sys/kernel/debug/tracing/events/kmem/kmalloc/trigger - - # cat /sys/kernel/debug/tracing/events/kmem/kmalloc/hist - # trigger info: hist:keys=call_site.sym:vals=bytes_req,bytes_alloc:sort=bytes_alloc.descending:size=2048 [active] - - { call_site: [ffffffffa046041c] i915_gem_execbuffer2 [i915] } hitcount: 7403 bytes_req: 4084360 bytes_alloc: 5958016 - { call_site: [ffffffff811e2a1b] seq_buf_alloc } hitcount: 541 bytes_req: 2213968 bytes_alloc: 2228224 - { call_site: [ffffffffa0489a66] intel_ring_begin [i915] } hitcount: 7404 bytes_req: 1066176 bytes_alloc: 1421568 - { call_site: [ffffffffa045e7c4] i915_gem_do_execbuffer.isra.23 [i915] } hitcount: 1565 bytes_req: 557368 bytes_alloc: 1037760 - { call_site: [ffffffff8125847d] ext4_htree_store_dirent } hitcount: 9557 bytes_req: 595778 bytes_alloc: 695744 - { call_site: [ffffffffa045e646] i915_gem_do_execbuffer.isra.23 [i915] } hitcount: 5839 bytes_req: 430680 bytes_alloc: 470400 - { call_site: [ffffffffa04c4a3c] intel_plane_duplicate_state [i915] } hitcount: 2388 bytes_req: 324768 bytes_alloc: 458496 - { call_site: [ffffffffa02911f2] drm_modeset_lock_crtc [drm] } hitcount: 3911 bytes_req: 219016 bytes_alloc: 250304 - { call_site: [ffffffff815f8d7b] sk_prot_alloc } hitcount: 235 bytes_req: 236880 bytes_alloc: 240640 - { call_site: [ffffffff8137e559] sg_kmalloc } hitcount: 557 bytes_req: 169024 bytes_alloc: 221760 - { call_site: [ffffffffa00b7c06] hid_report_raw_event [hid] } hitcount: 9378 bytes_req: 187548 bytes_alloc: 206312 - { call_site: [ffffffffa04a580c] intel_crtc_page_flip [i915] } hitcount: 1519 bytes_req: 157976 bytes_alloc: 194432 - . - . - . - { call_site: [ffffffff8109bd3b] sched_autogroup_create_attach } hitcount: 2 bytes_req: 144 bytes_alloc: 192 - { call_site: [ffffffff81097ee8] alloc_rt_sched_group } hitcount: 2 bytes_req: 128 bytes_alloc: 128 - { call_site: [ffffffff8109524a] alloc_fair_sched_group } hitcount: 2 bytes_req: 128 bytes_alloc: 128 - { call_site: [ffffffff81095225] alloc_fair_sched_group } hitcount: 2 bytes_req: 128 bytes_alloc: 128 - { call_site: [ffffffff81097ec2] alloc_rt_sched_group } hitcount: 2 bytes_req: 128 bytes_alloc: 128 - { call_site: [ffffffff81213e80] load_elf_binary } hitcount: 3 bytes_req: 84 bytes_alloc: 96 - { call_site: [ffffffff81079a2e] kthread_create_on_node } hitcount: 1 bytes_req: 56 bytes_alloc: 64 - { call_site: [ffffffffa00bf6fe] hidraw_send_report [hid] } hitcount: 1 bytes_req: 7 bytes_alloc: 8 - { call_site: [ffffffff8154bc62] usb_control_msg } hitcount: 1 bytes_req: 8 bytes_alloc: 8 - { call_site: [ffffffffa00bf1ca] hidraw_report_event [hid] } hitcount: 1 bytes_req: 7 bytes_alloc: 8 - - Totals: - Hits: 66598 - Entries: 65 - Dropped: 0 - - Finally, to finish off our kmalloc example, instead of simply having - the hist trigger display symbolic call_sites, we can have the hist - trigger additionally display the complete set of kernel stack traces - that led to each call_site. To do that, we simply use the special - value 'stacktrace' for the key parameter: - - # echo 'hist:keys=stacktrace:values=bytes_req,bytes_alloc:sort=bytes_alloc' > \ - /sys/kernel/debug/tracing/events/kmem/kmalloc/trigger - - The above trigger will use the kernel stack trace in effect when an - event is triggered as the key for the hash table. This allows the - enumeration of every kernel callpath that led up to a particular - event, along with a running total of any of the event fields for - that event. Here we tally bytes requested and bytes allocated for - every callpath in the system that led up to a kmalloc (in this case - every callpath to a kmalloc for a kernel compile): - - # cat /sys/kernel/debug/tracing/events/kmem/kmalloc/hist - # trigger info: hist:keys=stacktrace:vals=bytes_req,bytes_alloc:sort=bytes_alloc:size=2048 [active] - - { stacktrace: - __kmalloc_track_caller+0x10b/0x1a0 - kmemdup+0x20/0x50 - hidraw_report_event+0x8a/0x120 [hid] - hid_report_raw_event+0x3ea/0x440 [hid] - hid_input_report+0x112/0x190 [hid] - hid_irq_in+0xc2/0x260 [usbhid] - __usb_hcd_giveback_urb+0x72/0x120 - usb_giveback_urb_bh+0x9e/0xe0 - tasklet_hi_action+0xf8/0x100 - __do_softirq+0x114/0x2c0 - irq_exit+0xa5/0xb0 - do_IRQ+0x5a/0xf0 - ret_from_intr+0x0/0x30 - cpuidle_enter+0x17/0x20 - cpu_startup_entry+0x315/0x3e0 - rest_init+0x7c/0x80 - } hitcount: 3 bytes_req: 21 bytes_alloc: 24 - { stacktrace: - __kmalloc_track_caller+0x10b/0x1a0 - kmemdup+0x20/0x50 - hidraw_report_event+0x8a/0x120 [hid] - hid_report_raw_event+0x3ea/0x440 [hid] - hid_input_report+0x112/0x190 [hid] - hid_irq_in+0xc2/0x260 [usbhid] - __usb_hcd_giveback_urb+0x72/0x120 - usb_giveback_urb_bh+0x9e/0xe0 - tasklet_hi_action+0xf8/0x100 - __do_softirq+0x114/0x2c0 - irq_exit+0xa5/0xb0 - do_IRQ+0x5a/0xf0 - ret_from_intr+0x0/0x30 - } hitcount: 3 bytes_req: 21 bytes_alloc: 24 - { stacktrace: - kmem_cache_alloc_trace+0xeb/0x150 - aa_alloc_task_context+0x27/0x40 - apparmor_cred_prepare+0x1f/0x50 - security_prepare_creds+0x16/0x20 - prepare_creds+0xdf/0x1a0 - SyS_capset+0xb5/0x200 - system_call_fastpath+0x12/0x6a - } hitcount: 1 bytes_req: 32 bytes_alloc: 32 - . - . - . - { stacktrace: - __kmalloc+0x11b/0x1b0 - i915_gem_execbuffer2+0x6c/0x2c0 [i915] - drm_ioctl+0x349/0x670 [drm] - do_vfs_ioctl+0x2f0/0x4f0 - SyS_ioctl+0x81/0xa0 - system_call_fastpath+0x12/0x6a - } hitcount: 17726 bytes_req: 13944120 bytes_alloc: 19593808 - { stacktrace: - __kmalloc+0x11b/0x1b0 - load_elf_phdrs+0x76/0xa0 - load_elf_binary+0x102/0x1650 - search_binary_handler+0x97/0x1d0 - do_execveat_common.isra.34+0x551/0x6e0 - SyS_execve+0x3a/0x50 - return_from_execve+0x0/0x23 - } hitcount: 33348 bytes_req: 17152128 bytes_alloc: 20226048 - { stacktrace: - kmem_cache_alloc_trace+0xeb/0x150 - apparmor_file_alloc_security+0x27/0x40 - security_file_alloc+0x16/0x20 - get_empty_filp+0x93/0x1c0 - path_openat+0x31/0x5f0 - do_filp_open+0x3a/0x90 - do_sys_open+0x128/0x220 - SyS_open+0x1e/0x20 - system_call_fastpath+0x12/0x6a - } hitcount: 4766422 bytes_req: 9532844 bytes_alloc: 38131376 - { stacktrace: - __kmalloc+0x11b/0x1b0 - seq_buf_alloc+0x1b/0x50 - seq_read+0x2cc/0x370 - proc_reg_read+0x3d/0x80 - __vfs_read+0x28/0xe0 - vfs_read+0x86/0x140 - SyS_read+0x46/0xb0 - system_call_fastpath+0x12/0x6a - } hitcount: 19133 bytes_req: 78368768 bytes_alloc: 78368768 - - Totals: - Hits: 6085872 - Entries: 253 - Dropped: 0 - - If you key a hist trigger on common_pid, in order for example to - gather and display sorted totals for each process, you can use the - special .execname modifier to display the executable names for the - processes in the table rather than raw pids. The example below - keeps a per-process sum of total bytes read: - - # echo 'hist:key=common_pid.execname:val=count:sort=count.descending' > \ - /sys/kernel/debug/tracing/events/syscalls/sys_enter_read/trigger - - # cat /sys/kernel/debug/tracing/events/syscalls/sys_enter_read/hist - # trigger info: hist:keys=common_pid.execname:vals=count:sort=count.descending:size=2048 [active] - - { common_pid: gnome-terminal [ 3196] } hitcount: 280 count: 1093512 - { common_pid: Xorg [ 1309] } hitcount: 525 count: 256640 - { common_pid: compiz [ 2889] } hitcount: 59 count: 254400 - { common_pid: bash [ 8710] } hitcount: 3 count: 66369 - { common_pid: dbus-daemon-lau [ 8703] } hitcount: 49 count: 47739 - { common_pid: irqbalance [ 1252] } hitcount: 27 count: 27648 - { common_pid: 01ifupdown [ 8705] } hitcount: 3 count: 17216 - { common_pid: dbus-daemon [ 772] } hitcount: 10 count: 12396 - { common_pid: Socket Thread [ 8342] } hitcount: 11 count: 11264 - { common_pid: nm-dhcp-client. [ 8701] } hitcount: 6 count: 7424 - { common_pid: gmain [ 1315] } hitcount: 18 count: 6336 - . - . - . - { common_pid: postgres [ 1892] } hitcount: 2 count: 32 - { common_pid: postgres [ 1891] } hitcount: 2 count: 32 - { common_pid: gmain [ 8704] } hitcount: 2 count: 32 - { common_pid: upstart-dbus-br [ 2740] } hitcount: 21 count: 21 - { common_pid: nm-dispatcher.a [ 8696] } hitcount: 1 count: 16 - { common_pid: indicator-datet [ 2904] } hitcount: 1 count: 16 - { common_pid: gdbus [ 2998] } hitcount: 1 count: 16 - { common_pid: rtkit-daemon [ 2052] } hitcount: 1 count: 8 - { common_pid: init [ 1] } hitcount: 2 count: 2 - - Totals: - Hits: 2116 - Entries: 51 - Dropped: 0 - - Similarly, if you key a hist trigger on syscall id, for example to - gather and display a list of systemwide syscall hits, you can use - the special .syscall modifier to display the syscall names rather - than raw ids. The example below keeps a running total of syscall - counts for the system during the run: - - # echo 'hist:key=id.syscall:val=hitcount' > \ - /sys/kernel/debug/tracing/events/raw_syscalls/sys_enter/trigger - - # cat /sys/kernel/debug/tracing/events/raw_syscalls/sys_enter/hist - # trigger info: hist:keys=id.syscall:vals=hitcount:sort=hitcount:size=2048 [active] - - { id: sys_fsync [ 74] } hitcount: 1 - { id: sys_newuname [ 63] } hitcount: 1 - { id: sys_prctl [157] } hitcount: 1 - { id: sys_statfs [137] } hitcount: 1 - { id: sys_symlink [ 88] } hitcount: 1 - { id: sys_sendmmsg [307] } hitcount: 1 - { id: sys_semctl [ 66] } hitcount: 1 - { id: sys_readlink [ 89] } hitcount: 3 - { id: sys_bind [ 49] } hitcount: 3 - { id: sys_getsockname [ 51] } hitcount: 3 - { id: sys_unlink [ 87] } hitcount: 3 - { id: sys_rename [ 82] } hitcount: 4 - { id: unknown_syscall [ 58] } hitcount: 4 - { id: sys_connect [ 42] } hitcount: 4 - { id: sys_getpid [ 39] } hitcount: 4 - . - . - . - { id: sys_rt_sigprocmask [ 14] } hitcount: 952 - { id: sys_futex [202] } hitcount: 1534 - { id: sys_write [ 1] } hitcount: 2689 - { id: sys_setitimer [ 38] } hitcount: 2797 - { id: sys_read [ 0] } hitcount: 3202 - { id: sys_select [ 23] } hitcount: 3773 - { id: sys_writev [ 20] } hitcount: 4531 - { id: sys_poll [ 7] } hitcount: 8314 - { id: sys_recvmsg [ 47] } hitcount: 13738 - { id: sys_ioctl [ 16] } hitcount: 21843 - - Totals: - Hits: 67612 - Entries: 72 - Dropped: 0 - - The syscall counts above provide a rough overall picture of system - call activity on the system; we can see for example that the most - popular system call on this system was the 'sys_ioctl' system call. - - We can use 'compound' keys to refine that number and provide some - further insight as to which processes exactly contribute to the - overall ioctl count. - - The command below keeps a hitcount for every unique combination of - system call id and pid - the end result is essentially a table - that keeps a per-pid sum of system call hits. The results are - sorted using the system call id as the primary key, and the - hitcount sum as the secondary key: - - # echo 'hist:key=id.syscall,common_pid.execname:val=hitcount:sort=id,hitcount' > \ - /sys/kernel/debug/tracing/events/raw_syscalls/sys_enter/trigger - - # cat /sys/kernel/debug/tracing/events/raw_syscalls/sys_enter/hist - # trigger info: hist:keys=id.syscall,common_pid.execname:vals=hitcount:sort=id.syscall,hitcount:size=2048 [active] - - { id: sys_read [ 0], common_pid: rtkit-daemon [ 1877] } hitcount: 1 - { id: sys_read [ 0], common_pid: gdbus [ 2976] } hitcount: 1 - { id: sys_read [ 0], common_pid: console-kit-dae [ 3400] } hitcount: 1 - { id: sys_read [ 0], common_pid: postgres [ 1865] } hitcount: 1 - { id: sys_read [ 0], common_pid: deja-dup-monito [ 3543] } hitcount: 2 - { id: sys_read [ 0], common_pid: NetworkManager [ 890] } hitcount: 2 - { id: sys_read [ 0], common_pid: evolution-calen [ 3048] } hitcount: 2 - { id: sys_read [ 0], common_pid: postgres [ 1864] } hitcount: 2 - { id: sys_read [ 0], common_pid: nm-applet [ 3022] } hitcount: 2 - { id: sys_read [ 0], common_pid: whoopsie [ 1212] } hitcount: 2 - . - . - . - { id: sys_ioctl [ 16], common_pid: bash [ 8479] } hitcount: 1 - { id: sys_ioctl [ 16], common_pid: bash [ 3472] } hitcount: 12 - { id: sys_ioctl [ 16], common_pid: gnome-terminal [ 3199] } hitcount: 16 - { id: sys_ioctl [ 16], common_pid: Xorg [ 1267] } hitcount: 1808 - { id: sys_ioctl [ 16], common_pid: compiz [ 2994] } hitcount: 5580 - . - . - . - { id: sys_waitid [247], common_pid: upstart-dbus-br [ 2690] } hitcount: 3 - { id: sys_waitid [247], common_pid: upstart-dbus-br [ 2688] } hitcount: 16 - { id: sys_inotify_add_watch [254], common_pid: gmain [ 975] } hitcount: 2 - { id: sys_inotify_add_watch [254], common_pid: gmain [ 3204] } hitcount: 4 - { id: sys_inotify_add_watch [254], common_pid: gmain [ 2888] } hitcount: 4 - { id: sys_inotify_add_watch [254], common_pid: gmain [ 3003] } hitcount: 4 - { id: sys_inotify_add_watch [254], common_pid: gmain [ 2873] } hitcount: 4 - { id: sys_inotify_add_watch [254], common_pid: gmain [ 3196] } hitcount: 6 - { id: sys_openat [257], common_pid: java [ 2623] } hitcount: 2 - { id: sys_eventfd2 [290], common_pid: ibus-ui-gtk3 [ 2760] } hitcount: 4 - { id: sys_eventfd2 [290], common_pid: compiz [ 2994] } hitcount: 6 - - Totals: - Hits: 31536 - Entries: 323 - Dropped: 0 - - The above list does give us a breakdown of the ioctl syscall by - pid, but it also gives us quite a bit more than that, which we - don't really care about at the moment. Since we know the syscall - id for sys_ioctl (16, displayed next to the sys_ioctl name), we - can use that to filter out all the other syscalls: - - # echo 'hist:key=id.syscall,common_pid.execname:val=hitcount:sort=id,hitcount if id == 16' > \ - /sys/kernel/debug/tracing/events/raw_syscalls/sys_enter/trigger - - # cat /sys/kernel/debug/tracing/events/raw_syscalls/sys_enter/hist - # trigger info: hist:keys=id.syscall,common_pid.execname:vals=hitcount:sort=id.syscall,hitcount:size=2048 if id == 16 [active] - - { id: sys_ioctl [ 16], common_pid: gmain [ 2769] } hitcount: 1 - { id: sys_ioctl [ 16], common_pid: evolution-addre [ 8571] } hitcount: 1 - { id: sys_ioctl [ 16], common_pid: gmain [ 3003] } hitcount: 1 - { id: sys_ioctl [ 16], common_pid: gmain [ 2781] } hitcount: 1 - { id: sys_ioctl [ 16], common_pid: gmain [ 2829] } hitcount: 1 - { id: sys_ioctl [ 16], common_pid: bash [ 8726] } hitcount: 1 - { id: sys_ioctl [ 16], common_pid: bash [ 8508] } hitcount: 1 - { id: sys_ioctl [ 16], common_pid: gmain [ 2970] } hitcount: 1 - { id: sys_ioctl [ 16], common_pid: gmain [ 2768] } hitcount: 1 - . - . - . - { id: sys_ioctl [ 16], common_pid: pool [ 8559] } hitcount: 45 - { id: sys_ioctl [ 16], common_pid: pool [ 8555] } hitcount: 48 - { id: sys_ioctl [ 16], common_pid: pool [ 8551] } hitcount: 48 - { id: sys_ioctl [ 16], common_pid: avahi-daemon [ 896] } hitcount: 66 - { id: sys_ioctl [ 16], common_pid: Xorg [ 1267] } hitcount: 26674 - { id: sys_ioctl [ 16], common_pid: compiz [ 2994] } hitcount: 73443 - - Totals: - Hits: 101162 - Entries: 103 - Dropped: 0 - - The above output shows that 'compiz' and 'Xorg' are far and away - the heaviest ioctl callers (which might lead to questions about - whether they really need to be making all those calls and to - possible avenues for further investigation.) - - The compound key examples used a key and a sum value (hitcount) to - sort the output, but we can just as easily use two keys instead. - Here's an example where we use a compound key composed of the the - common_pid and size event fields. Sorting with pid as the primary - key and 'size' as the secondary key allows us to display an - ordered summary of the recvfrom sizes, with counts, received by - each process: - - # echo 'hist:key=common_pid.execname,size:val=hitcount:sort=common_pid,size' > \ - /sys/kernel/debug/tracing/events/syscalls/sys_enter_recvfrom/trigger - - # cat /sys/kernel/debug/tracing/events/syscalls/sys_enter_recvfrom/hist - # trigger info: hist:keys=common_pid.execname,size:vals=hitcount:sort=common_pid.execname,size:size=2048 [active] - - { common_pid: smbd [ 784], size: 4 } hitcount: 1 - { common_pid: dnsmasq [ 1412], size: 4096 } hitcount: 672 - { common_pid: postgres [ 1796], size: 1000 } hitcount: 6 - { common_pid: postgres [ 1867], size: 1000 } hitcount: 10 - { common_pid: bamfdaemon [ 2787], size: 28 } hitcount: 2 - { common_pid: bamfdaemon [ 2787], size: 14360 } hitcount: 1 - { common_pid: compiz [ 2994], size: 8 } hitcount: 1 - { common_pid: compiz [ 2994], size: 20 } hitcount: 11 - { common_pid: gnome-terminal [ 3199], size: 4 } hitcount: 2 - { common_pid: firefox [ 8817], size: 4 } hitcount: 1 - { common_pid: firefox [ 8817], size: 8 } hitcount: 5 - { common_pid: firefox [ 8817], size: 588 } hitcount: 2 - { common_pid: firefox [ 8817], size: 628 } hitcount: 1 - { common_pid: firefox [ 8817], size: 6944 } hitcount: 1 - { common_pid: firefox [ 8817], size: 408880 } hitcount: 2 - { common_pid: firefox [ 8822], size: 8 } hitcount: 2 - { common_pid: firefox [ 8822], size: 160 } hitcount: 2 - { common_pid: firefox [ 8822], size: 320 } hitcount: 2 - { common_pid: firefox [ 8822], size: 352 } hitcount: 1 - . - . - . - { common_pid: pool [ 8923], size: 1960 } hitcount: 10 - { common_pid: pool [ 8923], size: 2048 } hitcount: 10 - { common_pid: pool [ 8924], size: 1960 } hitcount: 10 - { common_pid: pool [ 8924], size: 2048 } hitcount: 10 - { common_pid: pool [ 8928], size: 1964 } hitcount: 4 - { common_pid: pool [ 8928], size: 1965 } hitcount: 2 - { common_pid: pool [ 8928], size: 2048 } hitcount: 6 - { common_pid: pool [ 8929], size: 1982 } hitcount: 1 - { common_pid: pool [ 8929], size: 2048 } hitcount: 1 - - Totals: - Hits: 2016 - Entries: 224 - Dropped: 0 - - The above example also illustrates the fact that although a compound - key is treated as a single entity for hashing purposes, the sub-keys - it's composed of can be accessed independently. - - The next example uses a string field as the hash key and - demonstrates how you can manually pause and continue a hist trigger. - In this example, we'll aggregate fork counts and don't expect a - large number of entries in the hash table, so we'll drop it to a - much smaller number, say 256: - - # echo 'hist:key=child_comm:val=hitcount:size=256' > \ - /sys/kernel/debug/tracing/events/sched/sched_process_fork/trigger - - # cat /sys/kernel/debug/tracing/events/sched/sched_process_fork/hist - # trigger info: hist:keys=child_comm:vals=hitcount:sort=hitcount:size=256 [active] - - { child_comm: dconf worker } hitcount: 1 - { child_comm: ibus-daemon } hitcount: 1 - { child_comm: whoopsie } hitcount: 1 - { child_comm: smbd } hitcount: 1 - { child_comm: gdbus } hitcount: 1 - { child_comm: kthreadd } hitcount: 1 - { child_comm: dconf worker } hitcount: 1 - { child_comm: evolution-alarm } hitcount: 2 - { child_comm: Socket Thread } hitcount: 2 - { child_comm: postgres } hitcount: 2 - { child_comm: bash } hitcount: 3 - { child_comm: compiz } hitcount: 3 - { child_comm: evolution-sourc } hitcount: 4 - { child_comm: dhclient } hitcount: 4 - { child_comm: pool } hitcount: 5 - { child_comm: nm-dispatcher.a } hitcount: 8 - { child_comm: firefox } hitcount: 8 - { child_comm: dbus-daemon } hitcount: 8 - { child_comm: glib-pacrunner } hitcount: 10 - { child_comm: evolution } hitcount: 23 - - Totals: - Hits: 89 - Entries: 20 - Dropped: 0 - - If we want to pause the hist trigger, we can simply append :pause to - the command that started the trigger. Notice that the trigger info - displays as [paused]: - - # echo 'hist:key=child_comm:val=hitcount:size=256:pause' >> \ - /sys/kernel/debug/tracing/events/sched/sched_process_fork/trigger - - # cat /sys/kernel/debug/tracing/events/sched/sched_process_fork/hist - # trigger info: hist:keys=child_comm:vals=hitcount:sort=hitcount:size=256 [paused] - - { child_comm: dconf worker } hitcount: 1 - { child_comm: kthreadd } hitcount: 1 - { child_comm: dconf worker } hitcount: 1 - { child_comm: gdbus } hitcount: 1 - { child_comm: ibus-daemon } hitcount: 1 - { child_comm: Socket Thread } hitcount: 2 - { child_comm: evolution-alarm } hitcount: 2 - { child_comm: smbd } hitcount: 2 - { child_comm: bash } hitcount: 3 - { child_comm: whoopsie } hitcount: 3 - { child_comm: compiz } hitcount: 3 - { child_comm: evolution-sourc } hitcount: 4 - { child_comm: pool } hitcount: 5 - { child_comm: postgres } hitcount: 6 - { child_comm: firefox } hitcount: 8 - { child_comm: dhclient } hitcount: 10 - { child_comm: emacs } hitcount: 12 - { child_comm: dbus-daemon } hitcount: 20 - { child_comm: nm-dispatcher.a } hitcount: 20 - { child_comm: evolution } hitcount: 35 - { child_comm: glib-pacrunner } hitcount: 59 - - Totals: - Hits: 199 - Entries: 21 - Dropped: 0 - - To manually continue having the trigger aggregate events, append - :cont instead. Notice that the trigger info displays as [active] - again, and the data has changed: - - # echo 'hist:key=child_comm:val=hitcount:size=256:cont' >> \ - /sys/kernel/debug/tracing/events/sched/sched_process_fork/trigger - - # cat /sys/kernel/debug/tracing/events/sched/sched_process_fork/hist - # trigger info: hist:keys=child_comm:vals=hitcount:sort=hitcount:size=256 [active] - - { child_comm: dconf worker } hitcount: 1 - { child_comm: dconf worker } hitcount: 1 - { child_comm: kthreadd } hitcount: 1 - { child_comm: gdbus } hitcount: 1 - { child_comm: ibus-daemon } hitcount: 1 - { child_comm: Socket Thread } hitcount: 2 - { child_comm: evolution-alarm } hitcount: 2 - { child_comm: smbd } hitcount: 2 - { child_comm: whoopsie } hitcount: 3 - { child_comm: compiz } hitcount: 3 - { child_comm: evolution-sourc } hitcount: 4 - { child_comm: bash } hitcount: 5 - { child_comm: pool } hitcount: 5 - { child_comm: postgres } hitcount: 6 - { child_comm: firefox } hitcount: 8 - { child_comm: dhclient } hitcount: 11 - { child_comm: emacs } hitcount: 12 - { child_comm: dbus-daemon } hitcount: 22 - { child_comm: nm-dispatcher.a } hitcount: 22 - { child_comm: evolution } hitcount: 35 - { child_comm: glib-pacrunner } hitcount: 59 - - Totals: - Hits: 206 - Entries: 21 - Dropped: 0 - - The previous example showed how to start and stop a hist trigger by - appending 'pause' and 'continue' to the hist trigger command. A - hist trigger can also be started in a paused state by initially - starting the trigger with ':pause' appended. This allows you to - start the trigger only when you're ready to start collecting data - and not before. For example, you could start the trigger in a - paused state, then unpause it and do something you want to measure, - then pause the trigger again when done. - - Of course, doing this manually can be difficult and error-prone, but - it is possible to automatically start and stop a hist trigger based - on some condition, via the enable_hist and disable_hist triggers. - - For example, suppose we wanted to take a look at the relative - weights in terms of skb length for each callpath that leads to a - netif_receieve_skb event when downloading a decent-sized file using - wget. - - First we set up an initially paused stacktrace trigger on the - netif_receive_skb event: - - # echo 'hist:key=stacktrace:vals=len:pause' > \ - /sys/kernel/debug/tracing/events/net/netif_receive_skb/trigger - - Next, we set up an 'enable_hist' trigger on the sched_process_exec - event, with an 'if filename==/usr/bin/wget' filter. The effect of - this new trigger is that it will 'unpause' the hist trigger we just - set up on netif_receive_skb if and only if it sees a - sched_process_exec event with a filename of '/usr/bin/wget'. When - that happens, all netif_receive_skb events are aggregated into a - hash table keyed on stacktrace: - - # echo 'enable_hist:net:netif_receive_skb if filename==/usr/bin/wget' > \ - /sys/kernel/debug/tracing/events/sched/sched_process_exec/trigger - - The aggregation continues until the netif_receive_skb is paused - again, which is what the following disable_hist event does by - creating a similar setup on the sched_process_exit event, using the - filter 'comm==wget': - - # echo 'disable_hist:net:netif_receive_skb if comm==wget' > \ - /sys/kernel/debug/tracing/events/sched/sched_process_exit/trigger - - Whenever a process exits and the comm field of the disable_hist - trigger filter matches 'comm==wget', the netif_receive_skb hist - trigger is disabled. - - The overall effect is that netif_receive_skb events are aggregated - into the hash table for only the duration of the wget. Executing a - wget command and then listing the 'hist' file will display the - output generated by the wget command: - - $ wget https://www.kernel.org/pub/linux/kernel/v3.x/patch-3.19.xz - - # cat /sys/kernel/debug/tracing/events/net/netif_receive_skb/hist - # trigger info: hist:keys=stacktrace:vals=len:sort=hitcount:size=2048 [paused] - - { stacktrace: - __netif_receive_skb_core+0x46d/0x990 - __netif_receive_skb+0x18/0x60 - netif_receive_skb_internal+0x23/0x90 - napi_gro_receive+0xc8/0x100 - ieee80211_deliver_skb+0xd6/0x270 [mac80211] - ieee80211_rx_handlers+0xccf/0x22f0 [mac80211] - ieee80211_prepare_and_rx_handle+0x4e7/0xc40 [mac80211] - ieee80211_rx+0x31d/0x900 [mac80211] - iwlagn_rx_reply_rx+0x3db/0x6f0 [iwldvm] - iwl_rx_dispatch+0x8e/0xf0 [iwldvm] - iwl_pcie_irq_handler+0xe3c/0x12f0 [iwlwifi] - irq_thread_fn+0x20/0x50 - irq_thread+0x11f/0x150 - kthread+0xd2/0xf0 - ret_from_fork+0x42/0x70 - } hitcount: 85 len: 28884 - { stacktrace: - __netif_receive_skb_core+0x46d/0x990 - __netif_receive_skb+0x18/0x60 - netif_receive_skb_internal+0x23/0x90 - napi_gro_complete+0xa4/0xe0 - dev_gro_receive+0x23a/0x360 - napi_gro_receive+0x30/0x100 - ieee80211_deliver_skb+0xd6/0x270 [mac80211] - ieee80211_rx_handlers+0xccf/0x22f0 [mac80211] - ieee80211_prepare_and_rx_handle+0x4e7/0xc40 [mac80211] - ieee80211_rx+0x31d/0x900 [mac80211] - iwlagn_rx_reply_rx+0x3db/0x6f0 [iwldvm] - iwl_rx_dispatch+0x8e/0xf0 [iwldvm] - iwl_pcie_irq_handler+0xe3c/0x12f0 [iwlwifi] - irq_thread_fn+0x20/0x50 - irq_thread+0x11f/0x150 - kthread+0xd2/0xf0 - } hitcount: 98 len: 664329 - { stacktrace: - __netif_receive_skb_core+0x46d/0x990 - __netif_receive_skb+0x18/0x60 - process_backlog+0xa8/0x150 - net_rx_action+0x15d/0x340 - __do_softirq+0x114/0x2c0 - do_softirq_own_stack+0x1c/0x30 - do_softirq+0x65/0x70 - __local_bh_enable_ip+0xb5/0xc0 - ip_finish_output+0x1f4/0x840 - ip_output+0x6b/0xc0 - ip_local_out_sk+0x31/0x40 - ip_send_skb+0x1a/0x50 - udp_send_skb+0x173/0x2a0 - udp_sendmsg+0x2bf/0x9f0 - inet_sendmsg+0x64/0xa0 - sock_sendmsg+0x3d/0x50 - } hitcount: 115 len: 13030 - { stacktrace: - __netif_receive_skb_core+0x46d/0x990 - __netif_receive_skb+0x18/0x60 - netif_receive_skb_internal+0x23/0x90 - napi_gro_complete+0xa4/0xe0 - napi_gro_flush+0x6d/0x90 - iwl_pcie_irq_handler+0x92a/0x12f0 [iwlwifi] - irq_thread_fn+0x20/0x50 - irq_thread+0x11f/0x150 - kthread+0xd2/0xf0 - ret_from_fork+0x42/0x70 - } hitcount: 934 len: 5512212 - - Totals: - Hits: 1232 - Entries: 4 - Dropped: 0 - - The above shows all the netif_receive_skb callpaths and their total - lengths for the duration of the wget command. - - The 'clear' hist trigger param can be used to clear the hash table. - Suppose we wanted to try another run of the previous example but - this time also wanted to see the complete list of events that went - into the histogram. In order to avoid having to set everything up - again, we can just clear the histogram first: - - # echo 'hist:key=stacktrace:vals=len:clear' >> \ - /sys/kernel/debug/tracing/events/net/netif_receive_skb/trigger - - Just to verify that it is in fact cleared, here's what we now see in - the hist file: - - # cat /sys/kernel/debug/tracing/events/net/netif_receive_skb/hist - # trigger info: hist:keys=stacktrace:vals=len:sort=hitcount:size=2048 [paused] - - Totals: - Hits: 0 - Entries: 0 - Dropped: 0 - - Since we want to see the detailed list of every netif_receive_skb - event occurring during the new run, which are in fact the same - events being aggregated into the hash table, we add some additional - 'enable_event' events to the triggering sched_process_exec and - sched_process_exit events as such: - - # echo 'enable_event:net:netif_receive_skb if filename==/usr/bin/wget' > \ - /sys/kernel/debug/tracing/events/sched/sched_process_exec/trigger - - # echo 'disable_event:net:netif_receive_skb if comm==wget' > \ - /sys/kernel/debug/tracing/events/sched/sched_process_exit/trigger - - If you read the trigger files for the sched_process_exec and - sched_process_exit triggers, you should see two triggers for each: - one enabling/disabling the hist aggregation and the other - enabling/disabling the logging of events: - - # cat /sys/kernel/debug/tracing/events/sched/sched_process_exec/trigger - enable_event:net:netif_receive_skb:unlimited if filename==/usr/bin/wget - enable_hist:net:netif_receive_skb:unlimited if filename==/usr/bin/wget - - # cat /sys/kernel/debug/tracing/events/sched/sched_process_exit/trigger - enable_event:net:netif_receive_skb:unlimited if comm==wget - disable_hist:net:netif_receive_skb:unlimited if comm==wget - - In other words, whenever either of the sched_process_exec or - sched_process_exit events is hit and matches 'wget', it enables or - disables both the histogram and the event log, and what you end up - with is a hash table and set of events just covering the specified - duration. Run the wget command again: - - $ wget https://www.kernel.org/pub/linux/kernel/v3.x/patch-3.19.xz - - Displaying the 'hist' file should show something similar to what you - saw in the last run, but this time you should also see the - individual events in the trace file: - - # cat /sys/kernel/debug/tracing/trace - - # tracer: nop - # - # entries-in-buffer/entries-written: 183/1426 #P:4 - # - # _-----=> irqs-off - # / _----=> need-resched - # | / _---=> hardirq/softirq - # || / _--=> preempt-depth - # ||| / delay - # TASK-PID CPU# |||| TIMESTAMP FUNCTION - # | | | |||| | | - wget-15108 [000] ..s1 31769.606929: netif_receive_skb: dev=lo skbaddr=ffff88009c353100 len=60 - wget-15108 [000] ..s1 31769.606999: netif_receive_skb: dev=lo skbaddr=ffff88009c353200 len=60 - dnsmasq-1382 [000] ..s1 31769.677652: netif_receive_skb: dev=lo skbaddr=ffff88009c352b00 len=130 - dnsmasq-1382 [000] ..s1 31769.685917: netif_receive_skb: dev=lo skbaddr=ffff88009c352200 len=138 - ##### CPU 2 buffer started #### - irq/29-iwlwifi-559 [002] ..s. 31772.031529: netif_receive_skb: dev=wlan0 skbaddr=ffff88009d433d00 len=2948 - irq/29-iwlwifi-559 [002] ..s. 31772.031572: netif_receive_skb: dev=wlan0 skbaddr=ffff88009d432200 len=1500 - irq/29-iwlwifi-559 [002] ..s. 31772.032196: netif_receive_skb: dev=wlan0 skbaddr=ffff88009d433100 len=2948 - irq/29-iwlwifi-559 [002] ..s. 31772.032761: netif_receive_skb: dev=wlan0 skbaddr=ffff88009d433000 len=2948 - irq/29-iwlwifi-559 [002] ..s. 31772.033220: netif_receive_skb: dev=wlan0 skbaddr=ffff88009d432e00 len=1500 - . - . - . - - The following example demonstrates how multiple hist triggers can be - attached to a given event. This capability can be useful for - creating a set of different summaries derived from the same set of - events, or for comparing the effects of different filters, among - other things. - - # echo 'hist:keys=skbaddr.hex:vals=len if len < 0' >> \ - /sys/kernel/debug/tracing/events/net/netif_receive_skb/trigger - # echo 'hist:keys=skbaddr.hex:vals=len if len > 4096' >> \ - /sys/kernel/debug/tracing/events/net/netif_receive_skb/trigger - # echo 'hist:keys=skbaddr.hex:vals=len if len == 256' >> \ - /sys/kernel/debug/tracing/events/net/netif_receive_skb/trigger - # echo 'hist:keys=skbaddr.hex:vals=len' >> \ - /sys/kernel/debug/tracing/events/net/netif_receive_skb/trigger - # echo 'hist:keys=len:vals=common_preempt_count' >> \ - /sys/kernel/debug/tracing/events/net/netif_receive_skb/trigger - - The above set of commands create four triggers differing only in - their filters, along with a completely different though fairly - nonsensical trigger. Note that in order to append multiple hist - triggers to the same file, you should use the '>>' operator to - append them ('>' will also add the new hist trigger, but will remove - any existing hist triggers beforehand). - - Displaying the contents of the 'hist' file for the event shows the - contents of all five histograms: - - # cat /sys/kernel/debug/tracing/events/net/netif_receive_skb/hist - - # event histogram - # - # trigger info: hist:keys=len:vals=hitcount,common_preempt_count:sort=hitcount:size=2048 [active] - # - - { len: 176 } hitcount: 1 common_preempt_count: 0 - { len: 223 } hitcount: 1 common_preempt_count: 0 - { len: 4854 } hitcount: 1 common_preempt_count: 0 - { len: 395 } hitcount: 1 common_preempt_count: 0 - { len: 177 } hitcount: 1 common_preempt_count: 0 - { len: 446 } hitcount: 1 common_preempt_count: 0 - { len: 1601 } hitcount: 1 common_preempt_count: 0 - . - . - . - { len: 1280 } hitcount: 66 common_preempt_count: 0 - { len: 116 } hitcount: 81 common_preempt_count: 40 - { len: 708 } hitcount: 112 common_preempt_count: 0 - { len: 46 } hitcount: 221 common_preempt_count: 0 - { len: 1264 } hitcount: 458 common_preempt_count: 0 - - Totals: - Hits: 1428 - Entries: 147 - Dropped: 0 - - - # event histogram - # - # trigger info: hist:keys=skbaddr.hex:vals=hitcount,len:sort=hitcount:size=2048 [active] - # - - { skbaddr: ffff8800baee5e00 } hitcount: 1 len: 130 - { skbaddr: ffff88005f3d5600 } hitcount: 1 len: 1280 - { skbaddr: ffff88005f3d4900 } hitcount: 1 len: 1280 - { skbaddr: ffff88009fed6300 } hitcount: 1 len: 115 - { skbaddr: ffff88009fe0ad00 } hitcount: 1 len: 115 - { skbaddr: ffff88008cdb1900 } hitcount: 1 len: 46 - { skbaddr: ffff880064b5ef00 } hitcount: 1 len: 118 - { skbaddr: ffff880044e3c700 } hitcount: 1 len: 60 - { skbaddr: ffff880100065900 } hitcount: 1 len: 46 - { skbaddr: ffff8800d46bd500 } hitcount: 1 len: 116 - { skbaddr: ffff88005f3d5f00 } hitcount: 1 len: 1280 - { skbaddr: ffff880100064700 } hitcount: 1 len: 365 - { skbaddr: ffff8800badb6f00 } hitcount: 1 len: 60 - . - . - . - { skbaddr: ffff88009fe0be00 } hitcount: 27 len: 24677 - { skbaddr: ffff88009fe0a400 } hitcount: 27 len: 23052 - { skbaddr: ffff88009fe0b700 } hitcount: 31 len: 25589 - { skbaddr: ffff88009fe0b600 } hitcount: 32 len: 27326 - { skbaddr: ffff88006a462800 } hitcount: 68 len: 71678 - { skbaddr: ffff88006a463700 } hitcount: 70 len: 72678 - { skbaddr: ffff88006a462b00 } hitcount: 71 len: 77589 - { skbaddr: ffff88006a463600 } hitcount: 73 len: 71307 - { skbaddr: ffff88006a462200 } hitcount: 81 len: 81032 - - Totals: - Hits: 1451 - Entries: 318 - Dropped: 0 - - - # event histogram - # - # trigger info: hist:keys=skbaddr.hex:vals=hitcount,len:sort=hitcount:size=2048 if len == 256 [active] - # - - - Totals: - Hits: 0 - Entries: 0 - Dropped: 0 - - - # event histogram - # - # trigger info: hist:keys=skbaddr.hex:vals=hitcount,len:sort=hitcount:size=2048 if len > 4096 [active] - # - - { skbaddr: ffff88009fd2c300 } hitcount: 1 len: 7212 - { skbaddr: ffff8800d2bcce00 } hitcount: 1 len: 7212 - { skbaddr: ffff8800d2bcd700 } hitcount: 1 len: 7212 - { skbaddr: ffff8800d2bcda00 } hitcount: 1 len: 21492 - { skbaddr: ffff8800ae2e2d00 } hitcount: 1 len: 7212 - { skbaddr: ffff8800d2bcdb00 } hitcount: 1 len: 7212 - { skbaddr: ffff88006a4df500 } hitcount: 1 len: 4854 - { skbaddr: ffff88008ce47b00 } hitcount: 1 len: 18636 - { skbaddr: ffff8800ae2e2200 } hitcount: 1 len: 12924 - { skbaddr: ffff88005f3e1000 } hitcount: 1 len: 4356 - { skbaddr: ffff8800d2bcdc00 } hitcount: 2 len: 24420 - { skbaddr: ffff8800d2bcc200 } hitcount: 2 len: 12996 - - Totals: - Hits: 14 - Entries: 12 - Dropped: 0 - - - # event histogram - # - # trigger info: hist:keys=skbaddr.hex:vals=hitcount,len:sort=hitcount:size=2048 if len < 0 [active] - # - - - Totals: - Hits: 0 - Entries: 0 - Dropped: 0 - - Named triggers can be used to have triggers share a common set of - histogram data. This capability is mostly useful for combining the - output of events generated by tracepoints contained inside inline - functions, but names can be used in a hist trigger on any event. - For example, these two triggers when hit will update the same 'len' - field in the shared 'foo' histogram data: - - # echo 'hist:name=foo:keys=skbaddr.hex:vals=len' > \ - /sys/kernel/debug/tracing/events/net/netif_receive_skb/trigger - # echo 'hist:name=foo:keys=skbaddr.hex:vals=len' > \ - /sys/kernel/debug/tracing/events/net/netif_rx/trigger - - You can see that they're updating common histogram data by reading - each event's hist files at the same time: - - # cat /sys/kernel/debug/tracing/events/net/netif_receive_skb/hist; - cat /sys/kernel/debug/tracing/events/net/netif_rx/hist - - # event histogram - # - # trigger info: hist:name=foo:keys=skbaddr.hex:vals=hitcount,len:sort=hitcount:size=2048 [active] - # - - { skbaddr: ffff88000ad53500 } hitcount: 1 len: 46 - { skbaddr: ffff8800af5a1500 } hitcount: 1 len: 76 - { skbaddr: ffff8800d62a1900 } hitcount: 1 len: 46 - { skbaddr: ffff8800d2bccb00 } hitcount: 1 len: 468 - { skbaddr: ffff8800d3c69900 } hitcount: 1 len: 46 - { skbaddr: ffff88009ff09100 } hitcount: 1 len: 52 - { skbaddr: ffff88010f13ab00 } hitcount: 1 len: 168 - { skbaddr: ffff88006a54f400 } hitcount: 1 len: 46 - { skbaddr: ffff8800d2bcc500 } hitcount: 1 len: 260 - { skbaddr: ffff880064505000 } hitcount: 1 len: 46 - { skbaddr: ffff8800baf24e00 } hitcount: 1 len: 32 - { skbaddr: ffff88009fe0ad00 } hitcount: 1 len: 46 - { skbaddr: ffff8800d3edff00 } hitcount: 1 len: 44 - { skbaddr: ffff88009fe0b400 } hitcount: 1 len: 168 - { skbaddr: ffff8800a1c55a00 } hitcount: 1 len: 40 - { skbaddr: ffff8800d2bcd100 } hitcount: 1 len: 40 - { skbaddr: ffff880064505f00 } hitcount: 1 len: 174 - { skbaddr: ffff8800a8bff200 } hitcount: 1 len: 160 - { skbaddr: ffff880044e3cc00 } hitcount: 1 len: 76 - { skbaddr: ffff8800a8bfe700 } hitcount: 1 len: 46 - { skbaddr: ffff8800d2bcdc00 } hitcount: 1 len: 32 - { skbaddr: ffff8800a1f64800 } hitcount: 1 len: 46 - { skbaddr: ffff8800d2bcde00 } hitcount: 1 len: 988 - { skbaddr: ffff88006a5dea00 } hitcount: 1 len: 46 - { skbaddr: ffff88002e37a200 } hitcount: 1 len: 44 - { skbaddr: ffff8800a1f32c00 } hitcount: 2 len: 676 - { skbaddr: ffff88000ad52600 } hitcount: 2 len: 107 - { skbaddr: ffff8800a1f91e00 } hitcount: 2 len: 92 - { skbaddr: ffff8800af5a0200 } hitcount: 2 len: 142 - { skbaddr: ffff8800d2bcc600 } hitcount: 2 len: 220 - { skbaddr: ffff8800ba36f500 } hitcount: 2 len: 92 - { skbaddr: ffff8800d021f800 } hitcount: 2 len: 92 - { skbaddr: ffff8800a1f33600 } hitcount: 2 len: 675 - { skbaddr: ffff8800a8bfff00 } hitcount: 3 len: 138 - { skbaddr: ffff8800d62a1300 } hitcount: 3 len: 138 - { skbaddr: ffff88002e37a100 } hitcount: 4 len: 184 - { skbaddr: ffff880064504400 } hitcount: 4 len: 184 - { skbaddr: ffff8800a8bfec00 } hitcount: 4 len: 184 - { skbaddr: ffff88000ad53700 } hitcount: 5 len: 230 - { skbaddr: ffff8800d2bcdb00 } hitcount: 5 len: 196 - { skbaddr: ffff8800a1f90000 } hitcount: 6 len: 276 - { skbaddr: ffff88006a54f900 } hitcount: 6 len: 276 - - Totals: - Hits: 81 - Entries: 42 - Dropped: 0 - # event histogram - # - # trigger info: hist:name=foo:keys=skbaddr.hex:vals=hitcount,len:sort=hitcount:size=2048 [active] - # - - { skbaddr: ffff88000ad53500 } hitcount: 1 len: 46 - { skbaddr: ffff8800af5a1500 } hitcount: 1 len: 76 - { skbaddr: ffff8800d62a1900 } hitcount: 1 len: 46 - { skbaddr: ffff8800d2bccb00 } hitcount: 1 len: 468 - { skbaddr: ffff8800d3c69900 } hitcount: 1 len: 46 - { skbaddr: ffff88009ff09100 } hitcount: 1 len: 52 - { skbaddr: ffff88010f13ab00 } hitcount: 1 len: 168 - { skbaddr: ffff88006a54f400 } hitcount: 1 len: 46 - { skbaddr: ffff8800d2bcc500 } hitcount: 1 len: 260 - { skbaddr: ffff880064505000 } hitcount: 1 len: 46 - { skbaddr: ffff8800baf24e00 } hitcount: 1 len: 32 - { skbaddr: ffff88009fe0ad00 } hitcount: 1 len: 46 - { skbaddr: ffff8800d3edff00 } hitcount: 1 len: 44 - { skbaddr: ffff88009fe0b400 } hitcount: 1 len: 168 - { skbaddr: ffff8800a1c55a00 } hitcount: 1 len: 40 - { skbaddr: ffff8800d2bcd100 } hitcount: 1 len: 40 - { skbaddr: ffff880064505f00 } hitcount: 1 len: 174 - { skbaddr: ffff8800a8bff200 } hitcount: 1 len: 160 - { skbaddr: ffff880044e3cc00 } hitcount: 1 len: 76 - { skbaddr: ffff8800a8bfe700 } hitcount: 1 len: 46 - { skbaddr: ffff8800d2bcdc00 } hitcount: 1 len: 32 - { skbaddr: ffff8800a1f64800 } hitcount: 1 len: 46 - { skbaddr: ffff8800d2bcde00 } hitcount: 1 len: 988 - { skbaddr: ffff88006a5dea00 } hitcount: 1 len: 46 - { skbaddr: ffff88002e37a200 } hitcount: 1 len: 44 - { skbaddr: ffff8800a1f32c00 } hitcount: 2 len: 676 - { skbaddr: ffff88000ad52600 } hitcount: 2 len: 107 - { skbaddr: ffff8800a1f91e00 } hitcount: 2 len: 92 - { skbaddr: ffff8800af5a0200 } hitcount: 2 len: 142 - { skbaddr: ffff8800d2bcc600 } hitcount: 2 len: 220 - { skbaddr: ffff8800ba36f500 } hitcount: 2 len: 92 - { skbaddr: ffff8800d021f800 } hitcount: 2 len: 92 - { skbaddr: ffff8800a1f33600 } hitcount: 2 len: 675 - { skbaddr: ffff8800a8bfff00 } hitcount: 3 len: 138 - { skbaddr: ffff8800d62a1300 } hitcount: 3 len: 138 - { skbaddr: ffff88002e37a100 } hitcount: 4 len: 184 - { skbaddr: ffff880064504400 } hitcount: 4 len: 184 - { skbaddr: ffff8800a8bfec00 } hitcount: 4 len: 184 - { skbaddr: ffff88000ad53700 } hitcount: 5 len: 230 - { skbaddr: ffff8800d2bcdb00 } hitcount: 5 len: 196 - { skbaddr: ffff8800a1f90000 } hitcount: 6 len: 276 - { skbaddr: ffff88006a54f900 } hitcount: 6 len: 276 - - Totals: - Hits: 81 - Entries: 42 - Dropped: 0 - - And here's an example that shows how to combine histogram data from - any two events even if they don't share any 'compatible' fields - other than 'hitcount' and 'stacktrace'. These commands create a - couple of triggers named 'bar' using those fields: - - # echo 'hist:name=bar:key=stacktrace:val=hitcount' > \ - /sys/kernel/debug/tracing/events/sched/sched_process_fork/trigger - # echo 'hist:name=bar:key=stacktrace:val=hitcount' > \ - /sys/kernel/debug/tracing/events/net/netif_rx/trigger - - And displaying the output of either shows some interesting if - somewhat confusing output: - - # cat /sys/kernel/debug/tracing/events/sched/sched_process_fork/hist - # cat /sys/kernel/debug/tracing/events/net/netif_rx/hist - - # event histogram - # - # trigger info: hist:name=bar:keys=stacktrace:vals=hitcount:sort=hitcount:size=2048 [active] - # - - { stacktrace: - _do_fork+0x18e/0x330 - kernel_thread+0x29/0x30 - kthreadd+0x154/0x1b0 - ret_from_fork+0x3f/0x70 - } hitcount: 1 - { stacktrace: - netif_rx_internal+0xb2/0xd0 - netif_rx_ni+0x20/0x70 - dev_loopback_xmit+0xaa/0xd0 - ip_mc_output+0x126/0x240 - ip_local_out_sk+0x31/0x40 - igmp_send_report+0x1e9/0x230 - igmp_timer_expire+0xe9/0x120 - call_timer_fn+0x39/0xf0 - run_timer_softirq+0x1e1/0x290 - __do_softirq+0xfd/0x290 - irq_exit+0x98/0xb0 - smp_apic_timer_interrupt+0x4a/0x60 - apic_timer_interrupt+0x6d/0x80 - cpuidle_enter+0x17/0x20 - call_cpuidle+0x3b/0x60 - cpu_startup_entry+0x22d/0x310 - } hitcount: 1 - { stacktrace: - netif_rx_internal+0xb2/0xd0 - netif_rx_ni+0x20/0x70 - dev_loopback_xmit+0xaa/0xd0 - ip_mc_output+0x17f/0x240 - ip_local_out_sk+0x31/0x40 - ip_send_skb+0x1a/0x50 - udp_send_skb+0x13e/0x270 - udp_sendmsg+0x2bf/0x980 - inet_sendmsg+0x67/0xa0 - sock_sendmsg+0x38/0x50 - SYSC_sendto+0xef/0x170 - SyS_sendto+0xe/0x10 - entry_SYSCALL_64_fastpath+0x12/0x6a - } hitcount: 2 - { stacktrace: - netif_rx_internal+0xb2/0xd0 - netif_rx+0x1c/0x60 - loopback_xmit+0x6c/0xb0 - dev_hard_start_xmit+0x219/0x3a0 - __dev_queue_xmit+0x415/0x4f0 - dev_queue_xmit_sk+0x13/0x20 - ip_finish_output2+0x237/0x340 - ip_finish_output+0x113/0x1d0 - ip_output+0x66/0xc0 - ip_local_out_sk+0x31/0x40 - ip_send_skb+0x1a/0x50 - udp_send_skb+0x16d/0x270 - udp_sendmsg+0x2bf/0x980 - inet_sendmsg+0x67/0xa0 - sock_sendmsg+0x38/0x50 - ___sys_sendmsg+0x14e/0x270 - } hitcount: 76 - { stacktrace: - netif_rx_internal+0xb2/0xd0 - netif_rx+0x1c/0x60 - loopback_xmit+0x6c/0xb0 - dev_hard_start_xmit+0x219/0x3a0 - __dev_queue_xmit+0x415/0x4f0 - dev_queue_xmit_sk+0x13/0x20 - ip_finish_output2+0x237/0x340 - ip_finish_output+0x113/0x1d0 - ip_output+0x66/0xc0 - ip_local_out_sk+0x31/0x40 - ip_send_skb+0x1a/0x50 - udp_send_skb+0x16d/0x270 - udp_sendmsg+0x2bf/0x980 - inet_sendmsg+0x67/0xa0 - sock_sendmsg+0x38/0x50 - ___sys_sendmsg+0x269/0x270 - } hitcount: 77 - { stacktrace: - netif_rx_internal+0xb2/0xd0 - netif_rx+0x1c/0x60 - loopback_xmit+0x6c/0xb0 - dev_hard_start_xmit+0x219/0x3a0 - __dev_queue_xmit+0x415/0x4f0 - dev_queue_xmit_sk+0x13/0x20 - ip_finish_output2+0x237/0x340 - ip_finish_output+0x113/0x1d0 - ip_output+0x66/0xc0 - ip_local_out_sk+0x31/0x40 - ip_send_skb+0x1a/0x50 - udp_send_skb+0x16d/0x270 - udp_sendmsg+0x2bf/0x980 - inet_sendmsg+0x67/0xa0 - sock_sendmsg+0x38/0x50 - SYSC_sendto+0xef/0x170 - } hitcount: 88 - { stacktrace: - _do_fork+0x18e/0x330 - SyS_clone+0x19/0x20 - entry_SYSCALL_64_fastpath+0x12/0x6a - } hitcount: 244 - - Totals: - Hits: 489 - Entries: 7 - Dropped: 0 + See Documentation/trace/histogram.txt for details and examples. @ Documentation/trace/ftrace.txt:542 @ After mounting tracefs you will have access to the control and output files See events.txt for more information. + timestamp_mode: + + Certain tracers may change the timestamp mode used when + logging trace events into the event buffer. Events with + different modes can coexist within a buffer but the mode in + effect when an event is logged determines which timestamp mode + is used for that event. The default timestamp mode is + 'delta'. + + Usual timestamp modes for tracing: + + # cat timestamp_mode + [delta] absolute + + The timestamp mode with the square brackets around it is the + one in effect. + + delta: Default timestamp mode - timestamp is a delta against + a per-buffer timestamp. + + absolute: The timestamp is a full timestamp, not a delta + against some other value. As such it takes up more + space and is less efficient. + hwlat_detector: Directory for the Hardware Latency Detector. @ Documentation/trace/histogram.txt:4 @ + Event Histograms + + Documentation written by Tom Zanussi + +1. Introduction +=============== + + Histogram triggers are special event triggers that can be used to + aggregate trace event data into histograms. For information on + trace events and event triggers, see Documentation/trace/events.txt. + + +2. Histogram Trigger Command +============================ + + A histogram trigger command is an event trigger command that + aggregates event hits into a hash table keyed on one or more trace + event format fields (or stacktrace) and a set of running totals + derived from one or more trace event format fields and/or event + counts (hitcount). + + The format of a hist trigger is as follows: + + hist:keys=<field1[,field2,...]>[:values=<field1[,field2,...]>] + [:sort=<field1[,field2,...]>][:size=#entries][:pause][:continue] + [:clear][:name=histname1] [if <filter>] + + When a matching event is hit, an entry is added to a hash table + using the key(s) and value(s) named. Keys and values correspond to + fields in the event's format description. Values must correspond to + numeric fields - on an event hit, the value(s) will be added to a + sum kept for that field. The special string 'hitcount' can be used + in place of an explicit value field - this is simply a count of + event hits. If 'values' isn't specified, an implicit 'hitcount' + value will be automatically created and used as the only value. + Keys can be any field, or the special string 'stacktrace', which + will use the event's kernel stacktrace as the key. The keywords + 'keys' or 'key' can be used to specify keys, and the keywords + 'values', 'vals', or 'val' can be used to specify values. Compound + keys consisting of up to two fields can be specified by the 'keys' + keyword. Hashing a compound key produces a unique entry in the + table for each unique combination of component keys, and can be + useful for providing more fine-grained summaries of event data. + Additionally, sort keys consisting of up to two fields can be + specified by the 'sort' keyword. If more than one field is + specified, the result will be a 'sort within a sort': the first key + is taken to be the primary sort key and the second the secondary + key. If a hist trigger is given a name using the 'name' parameter, + its histogram data will be shared with other triggers of the same + name, and trigger hits will update this common data. Only triggers + with 'compatible' fields can be combined in this way; triggers are + 'compatible' if the fields named in the trigger share the same + number and type of fields and those fields also have the same names. + Note that any two events always share the compatible 'hitcount' and + 'stacktrace' fields and can therefore be combined using those + fields, however pointless that may be. + + 'hist' triggers add a 'hist' file to each event's subdirectory. + Reading the 'hist' file for the event will dump the hash table in + its entirety to stdout. If there are multiple hist triggers + attached to an event, there will be a table for each trigger in the + output. The table displayed for a named trigger will be the same as + any other instance having the same name. Each printed hash table + entry is a simple list of the keys and values comprising the entry; + keys are printed first and are delineated by curly braces, and are + followed by the set of value fields for the entry. By default, + numeric fields are displayed as base-10 integers. This can be + modified by appending any of the following modifiers to the field + name: + + .hex display a number as a hex value + .sym display an address as a symbol + .sym-offset display an address as a symbol and offset + .syscall display a syscall id as a system call name + .execname display a common_pid as a program name + .log2 display log2 value rather than raw number + .usecs display a common_timestamp in microseconds + + Note that in general the semantics of a given field aren't + interpreted when applying a modifier to it, but there are some + restrictions to be aware of in this regard: + + - only the 'hex' modifier can be used for values (because values + are essentially sums, and the other modifiers don't make sense + in that context). + - the 'execname' modifier can only be used on a 'common_pid'. The + reason for this is that the execname is simply the 'comm' value + saved for the 'current' process when an event was triggered, + which is the same as the common_pid value saved by the event + tracing code. Trying to apply that comm value to other pid + values wouldn't be correct, and typically events that care save + pid-specific comm fields in the event itself. + + A typical usage scenario would be the following to enable a hist + trigger, read its current contents, and then turn it off: + + # echo 'hist:keys=skbaddr.hex:vals=len' > \ + /sys/kernel/debug/tracing/events/net/netif_rx/trigger + + # cat /sys/kernel/debug/tracing/events/net/netif_rx/hist + + # echo '!hist:keys=skbaddr.hex:vals=len' > \ + /sys/kernel/debug/tracing/events/net/netif_rx/trigger + + The trigger file itself can be read to show the details of the + currently attached hist trigger. This information is also displayed + at the top of the 'hist' file when read. + + By default, the size of the hash table is 2048 entries. The 'size' + parameter can be used to specify more or fewer than that. The units + are in terms of hashtable entries - if a run uses more entries than + specified, the results will show the number of 'drops', the number + of hits that were ignored. The size should be a power of 2 between + 128 and 131072 (any non- power-of-2 number specified will be rounded + up). + + The 'sort' parameter can be used to specify a value field to sort + on. The default if unspecified is 'hitcount' and the default sort + order is 'ascending'. To sort in the opposite direction, append + .descending' to the sort key. + + The 'pause' parameter can be used to pause an existing hist trigger + or to start a hist trigger but not log any events until told to do + so. 'continue' or 'cont' can be used to start or restart a paused + hist trigger. + + The 'clear' parameter will clear the contents of a running hist + trigger and leave its current paused/active state. + + Note that the 'pause', 'cont', and 'clear' parameters should be + applied using 'append' shell operator ('>>') if applied to an + existing trigger, rather than via the '>' operator, which will cause + the trigger to be removed through truncation. + +- enable_hist/disable_hist + + The enable_hist and disable_hist triggers can be used to have one + event conditionally start and stop another event's already-attached + hist trigger. Any number of enable_hist and disable_hist triggers + can be attached to a given event, allowing that event to kick off + and stop aggregations on a host of other events. + + The format is very similar to the enable/disable_event triggers: + + enable_hist:<system>:<event>[:count] + disable_hist:<system>:<event>[:count] + + Instead of enabling or disabling the tracing of the target event + into the trace buffer as the enable/disable_event triggers do, the + enable/disable_hist triggers enable or disable the aggregation of + the target event into a hash table. + + A typical usage scenario for the enable_hist/disable_hist triggers + would be to first set up a paused hist trigger on some event, + followed by an enable_hist/disable_hist pair that turns the hist + aggregation on and off when conditions of interest are hit: + + # echo 'hist:keys=skbaddr.hex:vals=len:pause' > \ + /sys/kernel/debug/tracing/events/net/netif_receive_skb/trigger + + # echo 'enable_hist:net:netif_receive_skb if filename==/usr/bin/wget' > \ + /sys/kernel/debug/tracing/events/sched/sched_process_exec/trigger + + # echo 'disable_hist:net:netif_receive_skb if comm==wget' > \ + /sys/kernel/debug/tracing/events/sched/sched_process_exit/trigger + + The above sets up an initially paused hist trigger which is unpaused + and starts aggregating events when a given program is executed, and + which stops aggregating when the process exits and the hist trigger + is paused again. + + The examples below provide a more concrete illustration of the + concepts and typical usage patterns discussed above. + + 'special' event fields + ------------------------ + + There are a number of 'special event fields' available for use as + keys or values in a hist trigger. These look like and behave as if + they were actual event fields, but aren't really part of the event's + field definition or format file. They are however available for any + event, and can be used anywhere an actual event field could be. + They are: + + common_timestamp u64 - timestamp (from ring buffer) associated + with the event, in nanoseconds. May be + modified by .usecs to have timestamps + interpreted as microseconds. + cpu int - the cpu on which the event occurred. + + Extended error information + -------------------------- + + For some error conditions encountered when invoking a hist trigger + command, extended error information is available via the + corresponding event's 'hist' file. Reading the hist file after an + error will display more detailed information about what went wrong, + if information is available. This extended error information will + be available until the next hist trigger command for that event. + + If available for a given error condition, the extended error + information and usage takes the following form: + + # echo xxx > /sys/kernel/debug/tracing/events/sched/sched_wakeup/trigger + echo: write error: Invalid argument + + # cat /sys/kernel/debug/tracing/events/sched/sched_wakeup/hist + ERROR: Couldn't yyy: zzz + Last command: xxx + +6.2 'hist' trigger examples +--------------------------- + + The first set of examples creates aggregations using the kmalloc + event. The fields that can be used for the hist trigger are listed + in the kmalloc event's format file: + + # cat /sys/kernel/debug/tracing/events/kmem/kmalloc/format + name: kmalloc + ID: 374 + format: + field:unsigned short common_type; offset:0; size:2; signed:0; + field:unsigned char common_flags; offset:2; size:1; signed:0; + field:unsigned char common_preempt_count; offset:3; size:1; signed:0; + field:int common_pid; offset:4; size:4; signed:1; + + field:unsigned long call_site; offset:8; size:8; signed:0; + field:const void * ptr; offset:16; size:8; signed:0; + field:size_t bytes_req; offset:24; size:8; signed:0; + field:size_t bytes_alloc; offset:32; size:8; signed:0; + field:gfp_t gfp_flags; offset:40; size:4; signed:0; + + We'll start by creating a hist trigger that generates a simple table + that lists the total number of bytes requested for each function in + the kernel that made one or more calls to kmalloc: + + # echo 'hist:key=call_site:val=bytes_req' > \ + /sys/kernel/debug/tracing/events/kmem/kmalloc/trigger + + This tells the tracing system to create a 'hist' trigger using the + call_site field of the kmalloc event as the key for the table, which + just means that each unique call_site address will have an entry + created for it in the table. The 'val=bytes_req' parameter tells + the hist trigger that for each unique entry (call_site) in the + table, it should keep a running total of the number of bytes + requested by that call_site. + + We'll let it run for awhile and then dump the contents of the 'hist' + file in the kmalloc event's subdirectory (for readability, a number + of entries have been omitted): + + # cat /sys/kernel/debug/tracing/events/kmem/kmalloc/hist + # trigger info: hist:keys=call_site:vals=bytes_req:sort=hitcount:size=2048 [active] + + { call_site: 18446744072106379007 } hitcount: 1 bytes_req: 176 + { call_site: 18446744071579557049 } hitcount: 1 bytes_req: 1024 + { call_site: 18446744071580608289 } hitcount: 1 bytes_req: 16384 + { call_site: 18446744071581827654 } hitcount: 1 bytes_req: 24 + { call_site: 18446744071580700980 } hitcount: 1 bytes_req: 8 + { call_site: 18446744071579359876 } hitcount: 1 bytes_req: 152 + { call_site: 18446744071580795365 } hitcount: 3 bytes_req: 144 + { call_site: 18446744071581303129 } hitcount: 3 bytes_req: 144 + { call_site: 18446744071580713234 } hitcount: 4 bytes_req: 2560 + { call_site: 18446744071580933750 } hitcount: 4 bytes_req: 736 + . + . + . + { call_site: 18446744072106047046 } hitcount: 69 bytes_req: 5576 + { call_site: 18446744071582116407 } hitcount: 73 bytes_req: 2336 + { call_site: 18446744072106054684 } hitcount: 136 bytes_req: 140504 + { call_site: 18446744072106224230 } hitcount: 136 bytes_req: 19584 + { call_site: 18446744072106078074 } hitcount: 153 bytes_req: 2448 + { call_site: 18446744072106062406 } hitcount: 153 bytes_req: 36720 + { call_site: 18446744071582507929 } hitcount: 153 bytes_req: 37088 + { call_site: 18446744072102520590 } hitcount: 273 bytes_req: 10920 + { call_site: 18446744071582143559 } hitcount: 358 bytes_req: 716 + { call_site: 18446744072106465852 } hitcount: 417 bytes_req: 56712 + { call_site: 18446744072102523378 } hitcount: 485 bytes_req: 27160 + { call_site: 18446744072099568646 } hitcount: 1676 bytes_req: 33520 + + Totals: + Hits: 4610 + Entries: 45 + Dropped: 0 + + The output displays a line for each entry, beginning with the key + specified in the trigger, followed by the value(s) also specified in + the trigger. At the beginning of the output is a line that displays + the trigger info, which can also be displayed by reading the + 'trigger' file: + + # cat /sys/kernel/debug/tracing/events/kmem/kmalloc/trigger + hist:keys=call_site:vals=bytes_req:sort=hitcount:size=2048 [active] + + At the end of the output are a few lines that display the overall + totals for the run. The 'Hits' field shows the total number of + times the event trigger was hit, the 'Entries' field shows the total + number of used entries in the hash table, and the 'Dropped' field + shows the number of hits that were dropped because the number of + used entries for the run exceeded the maximum number of entries + allowed for the table (normally 0, but if not a hint that you may + want to increase the size of the table using the 'size' parameter). + + Notice in the above output that there's an extra field, 'hitcount', + which wasn't specified in the trigger. Also notice that in the + trigger info output, there's a parameter, 'sort=hitcount', which + wasn't specified in the trigger either. The reason for that is that + every trigger implicitly keeps a count of the total number of hits + attributed to a given entry, called the 'hitcount'. That hitcount + information is explicitly displayed in the output, and in the + absence of a user-specified sort parameter, is used as the default + sort field. + + The value 'hitcount' can be used in place of an explicit value in + the 'values' parameter if you don't really need to have any + particular field summed and are mainly interested in hit + frequencies. + + To turn the hist trigger off, simply call up the trigger in the + command history and re-execute it with a '!' prepended: + + # echo '!hist:key=call_site:val=bytes_req' > \ + /sys/kernel/debug/tracing/events/kmem/kmalloc/trigger + + Finally, notice that the call_site as displayed in the output above + isn't really very useful. It's an address, but normally addresses + are displayed in hex. To have a numeric field displayed as a hex + value, simply append '.hex' to the field name in the trigger: + + # echo 'hist:key=call_site.hex:val=bytes_req' > \ + /sys/kernel/debug/tracing/events/kmem/kmalloc/trigger + + # cat /sys/kernel/debug/tracing/events/kmem/kmalloc/hist + # trigger info: hist:keys=call_site.hex:vals=bytes_req:sort=hitcount:size=2048 [active] + + { call_site: ffffffffa026b291 } hitcount: 1 bytes_req: 433 + { call_site: ffffffffa07186ff } hitcount: 1 bytes_req: 176 + { call_site: ffffffff811ae721 } hitcount: 1 bytes_req: 16384 + { call_site: ffffffff811c5134 } hitcount: 1 bytes_req: 8 + { call_site: ffffffffa04a9ebb } hitcount: 1 bytes_req: 511 + { call_site: ffffffff8122e0a6 } hitcount: 1 bytes_req: 12 + { call_site: ffffffff8107da84 } hitcount: 1 bytes_req: 152 + { call_site: ffffffff812d8246 } hitcount: 1 bytes_req: 24 + { call_site: ffffffff811dc1e5 } hitcount: 3 bytes_req: 144 + { call_site: ffffffffa02515e8 } hitcount: 3 bytes_req: 648 + { call_site: ffffffff81258159 } hitcount: 3 bytes_req: 144 + { call_site: ffffffff811c80f4 } hitcount: 4 bytes_req: 544 + . + . + . + { call_site: ffffffffa06c7646 } hitcount: 106 bytes_req: 8024 + { call_site: ffffffffa06cb246 } hitcount: 132 bytes_req: 31680 + { call_site: ffffffffa06cef7a } hitcount: 132 bytes_req: 2112 + { call_site: ffffffff8137e399 } hitcount: 132 bytes_req: 23232 + { call_site: ffffffffa06c941c } hitcount: 185 bytes_req: 171360 + { call_site: ffffffffa06f2a66 } hitcount: 185 bytes_req: 26640 + { call_site: ffffffffa036a70e } hitcount: 265 bytes_req: 10600 + { call_site: ffffffff81325447 } hitcount: 292 bytes_req: 584 + { call_site: ffffffffa072da3c } hitcount: 446 bytes_req: 60656 + { call_site: ffffffffa036b1f2 } hitcount: 526 bytes_req: 29456 + { call_site: ffffffffa0099c06 } hitcount: 1780 bytes_req: 35600 + + Totals: + Hits: 4775 + Entries: 46 + Dropped: 0 + + Even that's only marginally more useful - while hex values do look + more like addresses, what users are typically more interested in + when looking at text addresses are the corresponding symbols + instead. To have an address displayed as symbolic value instead, + simply append '.sym' or '.sym-offset' to the field name in the + trigger: + + # echo 'hist:key=call_site.sym:val=bytes_req' > \ + /sys/kernel/debug/tracing/events/kmem/kmalloc/trigger + + # cat /sys/kernel/debug/tracing/events/kmem/kmalloc/hist + # trigger info: hist:keys=call_site.sym:vals=bytes_req:sort=hitcount:size=2048 [active] + + { call_site: [ffffffff810adcb9] syslog_print_all } hitcount: 1 bytes_req: 1024 + { call_site: [ffffffff8154bc62] usb_control_msg } hitcount: 1 bytes_req: 8 + { call_site: [ffffffffa00bf6fe] hidraw_send_report [hid] } hitcount: 1 bytes_req: 7 + { call_site: [ffffffff8154acbe] usb_alloc_urb } hitcount: 1 bytes_req: 192 + { call_site: [ffffffffa00bf1ca] hidraw_report_event [hid] } hitcount: 1 bytes_req: 7 + { call_site: [ffffffff811e3a25] __seq_open_private } hitcount: 1 bytes_req: 40 + { call_site: [ffffffff8109524a] alloc_fair_sched_group } hitcount: 2 bytes_req: 128 + { call_site: [ffffffff811febd5] fsnotify_alloc_group } hitcount: 2 bytes_req: 528 + { call_site: [ffffffff81440f58] __tty_buffer_request_room } hitcount: 2 bytes_req: 2624 + { call_site: [ffffffff81200ba6] inotify_new_group } hitcount: 2 bytes_req: 96 + { call_site: [ffffffffa05e19af] ieee80211_start_tx_ba_session [mac80211] } hitcount: 2 bytes_req: 464 + { call_site: [ffffffff81672406] tcp_get_metrics } hitcount: 2 bytes_req: 304 + { call_site: [ffffffff81097ec2] alloc_rt_sched_group } hitcount: 2 bytes_req: 128 + { call_site: [ffffffff81089b05] sched_create_group } hitcount: 2 bytes_req: 1424 + . + . + . + { call_site: [ffffffffa04a580c] intel_crtc_page_flip [i915] } hitcount: 1185 bytes_req: 123240 + { call_site: [ffffffffa0287592] drm_mode_page_flip_ioctl [drm] } hitcount: 1185 bytes_req: 104280 + { call_site: [ffffffffa04c4a3c] intel_plane_duplicate_state [i915] } hitcount: 1402 bytes_req: 190672 + { call_site: [ffffffff812891ca] ext4_find_extent } hitcount: 1518 bytes_req: 146208 + { call_site: [ffffffffa029070e] drm_vma_node_allow [drm] } hitcount: 1746 bytes_req: 69840 + { call_site: [ffffffffa045e7c4] i915_gem_do_execbuffer.isra.23 [i915] } hitcount: 2021 bytes_req: 792312 + { call_site: [ffffffffa02911f2] drm_modeset_lock_crtc [drm] } hitcount: 2592 bytes_req: 145152 + { call_site: [ffffffffa0489a66] intel_ring_begin [i915] } hitcount: 2629 bytes_req: 378576 + { call_site: [ffffffffa046041c] i915_gem_execbuffer2 [i915] } hitcount: 2629 bytes_req: 3783248 + { call_site: [ffffffff81325607] apparmor_file_alloc_security } hitcount: 5192 bytes_req: 10384 + { call_site: [ffffffffa00b7c06] hid_report_raw_event [hid] } hitcount: 5529 bytes_req: 110584 + { call_site: [ffffffff8131ebf7] aa_alloc_task_context } hitcount: 21943 bytes_req: 702176 + { call_site: [ffffffff8125847d] ext4_htree_store_dirent } hitcount: 55759 bytes_req: 5074265 + + Totals: + Hits: 109928 + Entries: 71 + Dropped: 0 + + Because the default sort key above is 'hitcount', the above shows a + the list of call_sites by increasing hitcount, so that at the bottom + we see the functions that made the most kmalloc calls during the + run. If instead we we wanted to see the top kmalloc callers in + terms of the number of bytes requested rather than the number of + calls, and we wanted the top caller to appear at the top, we can use + the 'sort' parameter, along with the 'descending' modifier: + + # echo 'hist:key=call_site.sym:val=bytes_req:sort=bytes_req.descending' > \ + /sys/kernel/debug/tracing/events/kmem/kmalloc/trigger + + # cat /sys/kernel/debug/tracing/events/kmem/kmalloc/hist + # trigger info: hist:keys=call_site.sym:vals=bytes_req:sort=bytes_req.descending:size=2048 [active] + + { call_site: [ffffffffa046041c] i915_gem_execbuffer2 [i915] } hitcount: 2186 bytes_req: 3397464 + { call_site: [ffffffffa045e7c4] i915_gem_do_execbuffer.isra.23 [i915] } hitcount: 1790 bytes_req: 712176 + { call_site: [ffffffff8125847d] ext4_htree_store_dirent } hitcount: 8132 bytes_req: 513135 + { call_site: [ffffffff811e2a1b] seq_buf_alloc } hitcount: 106 bytes_req: 440128 + { call_site: [ffffffffa0489a66] intel_ring_begin [i915] } hitcount: 2186 bytes_req: 314784 + { call_site: [ffffffff812891ca] ext4_find_extent } hitcount: 2174 bytes_req: 208992 + { call_site: [ffffffff811ae8e1] __kmalloc } hitcount: 8 bytes_req: 131072 + { call_site: [ffffffffa04c4a3c] intel_plane_duplicate_state [i915] } hitcount: 859 bytes_req: 116824 + { call_site: [ffffffffa02911f2] drm_modeset_lock_crtc [drm] } hitcount: 1834 bytes_req: 102704 + { call_site: [ffffffffa04a580c] intel_crtc_page_flip [i915] } hitcount: 972 bytes_req: 101088 + { call_site: [ffffffffa0287592] drm_mode_page_flip_ioctl [drm] } hitcount: 972 bytes_req: 85536 + { call_site: [ffffffffa00b7c06] hid_report_raw_event [hid] } hitcount: 3333 bytes_req: 66664 + { call_site: [ffffffff8137e559] sg_kmalloc } hitcount: 209 bytes_req: 61632 + . + . + . + { call_site: [ffffffff81095225] alloc_fair_sched_group } hitcount: 2 bytes_req: 128 + { call_site: [ffffffff81097ec2] alloc_rt_sched_group } hitcount: 2 bytes_req: 128 + { call_site: [ffffffff812d8406] copy_semundo } hitcount: 2 bytes_req: 48 + { call_site: [ffffffff81200ba6] inotify_new_group } hitcount: 1 bytes_req: 48 + { call_site: [ffffffffa027121a] drm_getmagic [drm] } hitcount: 1 bytes_req: 48 + { call_site: [ffffffff811e3a25] __seq_open_private } hitcount: 1 bytes_req: 40 + { call_site: [ffffffff811c52f4] bprm_change_interp } hitcount: 2 bytes_req: 16 + { call_site: [ffffffff8154bc62] usb_control_msg } hitcount: 1 bytes_req: 8 + { call_site: [ffffffffa00bf1ca] hidraw_report_event [hid] } hitcount: 1 bytes_req: 7 + { call_site: [ffffffffa00bf6fe] hidraw_send_report [hid] } hitcount: 1 bytes_req: 7 + + Totals: + Hits: 32133 + Entries: 81 + Dropped: 0 + + To display the offset and size information in addition to the symbol + name, just use 'sym-offset' instead: + + # echo 'hist:key=call_site.sym-offset:val=bytes_req:sort=bytes_req.descending' > \ + /sys/kernel/debug/tracing/events/kmem/kmalloc/trigger + + # cat /sys/kernel/debug/tracing/events/kmem/kmalloc/hist + # trigger info: hist:keys=call_site.sym-offset:vals=bytes_req:sort=bytes_req.descending:size=2048 [active] + + { call_site: [ffffffffa046041c] i915_gem_execbuffer2+0x6c/0x2c0 [i915] } hitcount: 4569 bytes_req: 3163720 + { call_site: [ffffffffa0489a66] intel_ring_begin+0xc6/0x1f0 [i915] } hitcount: 4569 bytes_req: 657936 + { call_site: [ffffffffa045e7c4] i915_gem_do_execbuffer.isra.23+0x694/0x1020 [i915] } hitcount: 1519 bytes_req: 472936 + { call_site: [ffffffffa045e646] i915_gem_do_execbuffer.isra.23+0x516/0x1020 [i915] } hitcount: 3050 bytes_req: 211832 + { call_site: [ffffffff811e2a1b] seq_buf_alloc+0x1b/0x50 } hitcount: 34 bytes_req: 148384 + { call_site: [ffffffffa04a580c] intel_crtc_page_flip+0xbc/0x870 [i915] } hitcount: 1385 bytes_req: 144040 + { call_site: [ffffffff811ae8e1] __kmalloc+0x191/0x1b0 } hitcount: 8 bytes_req: 131072 + { call_site: [ffffffffa0287592] drm_mode_page_flip_ioctl+0x282/0x360 [drm] } hitcount: 1385 bytes_req: 121880 + { call_site: [ffffffffa02911f2] drm_modeset_lock_crtc+0x32/0x100 [drm] } hitcount: 1848 bytes_req: 103488 + { call_site: [ffffffffa04c4a3c] intel_plane_duplicate_state+0x2c/0xa0 [i915] } hitcount: 461 bytes_req: 62696 + { call_site: [ffffffffa029070e] drm_vma_node_allow+0x2e/0xd0 [drm] } hitcount: 1541 bytes_req: 61640 + { call_site: [ffffffff815f8d7b] sk_prot_alloc+0xcb/0x1b0 } hitcount: 57 bytes_req: 57456 + . + . + . + { call_site: [ffffffff8109524a] alloc_fair_sched_group+0x5a/0x1a0 } hitcount: 2 bytes_req: 128 + { call_site: [ffffffffa027b921] drm_vm_open_locked+0x31/0xa0 [drm] } hitcount: 3 bytes_req: 96 + { call_site: [ffffffff8122e266] proc_self_follow_link+0x76/0xb0 } hitcount: 8 bytes_req: 96 + { call_site: [ffffffff81213e80] load_elf_binary+0x240/0x1650 } hitcount: 3 bytes_req: 84 + { call_site: [ffffffff8154bc62] usb_control_msg+0x42/0x110 } hitcount: 1 bytes_req: 8 + { call_site: [ffffffffa00bf6fe] hidraw_send_report+0x7e/0x1a0 [hid] } hitcount: 1 bytes_req: 7 + { call_site: [ffffffffa00bf1ca] hidraw_report_event+0x8a/0x120 [hid] } hitcount: 1 bytes_req: 7 + + Totals: + Hits: 26098 + Entries: 64 + Dropped: 0 + + We can also add multiple fields to the 'values' parameter. For + example, we might want to see the total number of bytes allocated + alongside bytes requested, and display the result sorted by bytes + allocated in a descending order: + + # echo 'hist:keys=call_site.sym:values=bytes_req,bytes_alloc:sort=bytes_alloc.descending' > \ + /sys/kernel/debug/tracing/events/kmem/kmalloc/trigger + + # cat /sys/kernel/debug/tracing/events/kmem/kmalloc/hist + # trigger info: hist:keys=call_site.sym:vals=bytes_req,bytes_alloc:sort=bytes_alloc.descending:size=2048 [active] + + { call_site: [ffffffffa046041c] i915_gem_execbuffer2 [i915] } hitcount: 7403 bytes_req: 4084360 bytes_alloc: 5958016 + { call_site: [ffffffff811e2a1b] seq_buf_alloc } hitcount: 541 bytes_req: 2213968 bytes_alloc: 2228224 + { call_site: [ffffffffa0489a66] intel_ring_begin [i915] } hitcount: 7404 bytes_req: 1066176 bytes_alloc: 1421568 + { call_site: [ffffffffa045e7c4] i915_gem_do_execbuffer.isra.23 [i915] } hitcount: 1565 bytes_req: 557368 bytes_alloc: 1037760 + { call_site: [ffffffff8125847d] ext4_htree_store_dirent } hitcount: 9557 bytes_req: 595778 bytes_alloc: 695744 + { call_site: [ffffffffa045e646] i915_gem_do_execbuffer.isra.23 [i915] } hitcount: 5839 bytes_req: 430680 bytes_alloc: 470400 + { call_site: [ffffffffa04c4a3c] intel_plane_duplicate_state [i915] } hitcount: 2388 bytes_req: 324768 bytes_alloc: 458496 + { call_site: [ffffffffa02911f2] drm_modeset_lock_crtc [drm] } hitcount: 3911 bytes_req: 219016 bytes_alloc: 250304 + { call_site: [ffffffff815f8d7b] sk_prot_alloc } hitcount: 235 bytes_req: 236880 bytes_alloc: 240640 + { call_site: [ffffffff8137e559] sg_kmalloc } hitcount: 557 bytes_req: 169024 bytes_alloc: 221760 + { call_site: [ffffffffa00b7c06] hid_report_raw_event [hid] } hitcount: 9378 bytes_req: 187548 bytes_alloc: 206312 + { call_site: [ffffffffa04a580c] intel_crtc_page_flip [i915] } hitcount: 1519 bytes_req: 157976 bytes_alloc: 194432 + . + . + . + { call_site: [ffffffff8109bd3b] sched_autogroup_create_attach } hitcount: 2 bytes_req: 144 bytes_alloc: 192 + { call_site: [ffffffff81097ee8] alloc_rt_sched_group } hitcount: 2 bytes_req: 128 bytes_alloc: 128 + { call_site: [ffffffff8109524a] alloc_fair_sched_group } hitcount: 2 bytes_req: 128 bytes_alloc: 128 + { call_site: [ffffffff81095225] alloc_fair_sched_group } hitcount: 2 bytes_req: 128 bytes_alloc: 128 + { call_site: [ffffffff81097ec2] alloc_rt_sched_group } hitcount: 2 bytes_req: 128 bytes_alloc: 128 + { call_site: [ffffffff81213e80] load_elf_binary } hitcount: 3 bytes_req: 84 bytes_alloc: 96 + { call_site: [ffffffff81079a2e] kthread_create_on_node } hitcount: 1 bytes_req: 56 bytes_alloc: 64 + { call_site: [ffffffffa00bf6fe] hidraw_send_report [hid] } hitcount: 1 bytes_req: 7 bytes_alloc: 8 + { call_site: [ffffffff8154bc62] usb_control_msg } hitcount: 1 bytes_req: 8 bytes_alloc: 8 + { call_site: [ffffffffa00bf1ca] hidraw_report_event [hid] } hitcount: 1 bytes_req: 7 bytes_alloc: 8 + + Totals: + Hits: 66598 + Entries: 65 + Dropped: 0 + + Finally, to finish off our kmalloc example, instead of simply having + the hist trigger display symbolic call_sites, we can have the hist + trigger additionally display the complete set of kernel stack traces + that led to each call_site. To do that, we simply use the special + value 'stacktrace' for the key parameter: + + # echo 'hist:keys=stacktrace:values=bytes_req,bytes_alloc:sort=bytes_alloc' > \ + /sys/kernel/debug/tracing/events/kmem/kmalloc/trigger + + The above trigger will use the kernel stack trace in effect when an + event is triggered as the key for the hash table. This allows the + enumeration of every kernel callpath that led up to a particular + event, along with a running total of any of the event fields for + that event. Here we tally bytes requested and bytes allocated for + every callpath in the system that led up to a kmalloc (in this case + every callpath to a kmalloc for a kernel compile): + + # cat /sys/kernel/debug/tracing/events/kmem/kmalloc/hist + # trigger info: hist:keys=stacktrace:vals=bytes_req,bytes_alloc:sort=bytes_alloc:size=2048 [active] + + { stacktrace: + __kmalloc_track_caller+0x10b/0x1a0 + kmemdup+0x20/0x50 + hidraw_report_event+0x8a/0x120 [hid] + hid_report_raw_event+0x3ea/0x440 [hid] + hid_input_report+0x112/0x190 [hid] + hid_irq_in+0xc2/0x260 [usbhid] + __usb_hcd_giveback_urb+0x72/0x120 + usb_giveback_urb_bh+0x9e/0xe0 + tasklet_hi_action+0xf8/0x100 + __do_softirq+0x114/0x2c0 + irq_exit+0xa5/0xb0 + do_IRQ+0x5a/0xf0 + ret_from_intr+0x0/0x30 + cpuidle_enter+0x17/0x20 + cpu_startup_entry+0x315/0x3e0 + rest_init+0x7c/0x80 + } hitcount: 3 bytes_req: 21 bytes_alloc: 24 + { stacktrace: + __kmalloc_track_caller+0x10b/0x1a0 + kmemdup+0x20/0x50 + hidraw_report_event+0x8a/0x120 [hid] + hid_report_raw_event+0x3ea/0x440 [hid] + hid_input_report+0x112/0x190 [hid] + hid_irq_in+0xc2/0x260 [usbhid] + __usb_hcd_giveback_urb+0x72/0x120 + usb_giveback_urb_bh+0x9e/0xe0 + tasklet_hi_action+0xf8/0x100 + __do_softirq+0x114/0x2c0 + irq_exit+0xa5/0xb0 + do_IRQ+0x5a/0xf0 + ret_from_intr+0x0/0x30 + } hitcount: 3 bytes_req: 21 bytes_alloc: 24 + { stacktrace: + kmem_cache_alloc_trace+0xeb/0x150 + aa_alloc_task_context+0x27/0x40 + apparmor_cred_prepare+0x1f/0x50 + security_prepare_creds+0x16/0x20 + prepare_creds+0xdf/0x1a0 + SyS_capset+0xb5/0x200 + system_call_fastpath+0x12/0x6a + } hitcount: 1 bytes_req: 32 bytes_alloc: 32 + . + . + . + { stacktrace: + __kmalloc+0x11b/0x1b0 + i915_gem_execbuffer2+0x6c/0x2c0 [i915] + drm_ioctl+0x349/0x670 [drm] + do_vfs_ioctl+0x2f0/0x4f0 + SyS_ioctl+0x81/0xa0 + system_call_fastpath+0x12/0x6a + } hitcount: 17726 bytes_req: 13944120 bytes_alloc: 19593808 + { stacktrace: + __kmalloc+0x11b/0x1b0 + load_elf_phdrs+0x76/0xa0 + load_elf_binary+0x102/0x1650 + search_binary_handler+0x97/0x1d0 + do_execveat_common.isra.34+0x551/0x6e0 + SyS_execve+0x3a/0x50 + return_from_execve+0x0/0x23 + } hitcount: 33348 bytes_req: 17152128 bytes_alloc: 20226048 + { stacktrace: + kmem_cache_alloc_trace+0xeb/0x150 + apparmor_file_alloc_security+0x27/0x40 + security_file_alloc+0x16/0x20 + get_empty_filp+0x93/0x1c0 + path_openat+0x31/0x5f0 + do_filp_open+0x3a/0x90 + do_sys_open+0x128/0x220 + SyS_open+0x1e/0x20 + system_call_fastpath+0x12/0x6a + } hitcount: 4766422 bytes_req: 9532844 bytes_alloc: 38131376 + { stacktrace: + __kmalloc+0x11b/0x1b0 + seq_buf_alloc+0x1b/0x50 + seq_read+0x2cc/0x370 + proc_reg_read+0x3d/0x80 + __vfs_read+0x28/0xe0 + vfs_read+0x86/0x140 + SyS_read+0x46/0xb0 + system_call_fastpath+0x12/0x6a + } hitcount: 19133 bytes_req: 78368768 bytes_alloc: 78368768 + + Totals: + Hits: 6085872 + Entries: 253 + Dropped: 0 + + If you key a hist trigger on common_pid, in order for example to + gather and display sorted totals for each process, you can use the + special .execname modifier to display the executable names for the + processes in the table rather than raw pids. The example below + keeps a per-process sum of total bytes read: + + # echo 'hist:key=common_pid.execname:val=count:sort=count.descending' > \ + /sys/kernel/debug/tracing/events/syscalls/sys_enter_read/trigger + + # cat /sys/kernel/debug/tracing/events/syscalls/sys_enter_read/hist + # trigger info: hist:keys=common_pid.execname:vals=count:sort=count.descending:size=2048 [active] + + { common_pid: gnome-terminal [ 3196] } hitcount: 280 count: 1093512 + { common_pid: Xorg [ 1309] } hitcount: 525 count: 256640 + { common_pid: compiz [ 2889] } hitcount: 59 count: 254400 + { common_pid: bash [ 8710] } hitcount: 3 count: 66369 + { common_pid: dbus-daemon-lau [ 8703] } hitcount: 49 count: 47739 + { common_pid: irqbalance [ 1252] } hitcount: 27 count: 27648 + { common_pid: 01ifupdown [ 8705] } hitcount: 3 count: 17216 + { common_pid: dbus-daemon [ 772] } hitcount: 10 count: 12396 + { common_pid: Socket Thread [ 8342] } hitcount: 11 count: 11264 + { common_pid: nm-dhcp-client. [ 8701] } hitcount: 6 count: 7424 + { common_pid: gmain [ 1315] } hitcount: 18 count: 6336 + . + . + . + { common_pid: postgres [ 1892] } hitcount: 2 count: 32 + { common_pid: postgres [ 1891] } hitcount: 2 count: 32 + { common_pid: gmain [ 8704] } hitcount: 2 count: 32 + { common_pid: upstart-dbus-br [ 2740] } hitcount: 21 count: 21 + { common_pid: nm-dispatcher.a [ 8696] } hitcount: 1 count: 16 + { common_pid: indicator-datet [ 2904] } hitcount: 1 count: 16 + { common_pid: gdbus [ 2998] } hitcount: 1 count: 16 + { common_pid: rtkit-daemon [ 2052] } hitcount: 1 count: 8 + { common_pid: init [ 1] } hitcount: 2 count: 2 + + Totals: + Hits: 2116 + Entries: 51 + Dropped: 0 + + Similarly, if you key a hist trigger on syscall id, for example to + gather and display a list of systemwide syscall hits, you can use + the special .syscall modifier to display the syscall names rather + than raw ids. The example below keeps a running total of syscall + counts for the system during the run: + + # echo 'hist:key=id.syscall:val=hitcount' > \ + /sys/kernel/debug/tracing/events/raw_syscalls/sys_enter/trigger + + # cat /sys/kernel/debug/tracing/events/raw_syscalls/sys_enter/hist + # trigger info: hist:keys=id.syscall:vals=hitcount:sort=hitcount:size=2048 [active] + + { id: sys_fsync [ 74] } hitcount: 1 + { id: sys_newuname [ 63] } hitcount: 1 + { id: sys_prctl [157] } hitcount: 1 + { id: sys_statfs [137] } hitcount: 1 + { id: sys_symlink [ 88] } hitcount: 1 + { id: sys_sendmmsg [307] } hitcount: 1 + { id: sys_semctl [ 66] } hitcount: 1 + { id: sys_readlink [ 89] } hitcount: 3 + { id: sys_bind [ 49] } hitcount: 3 + { id: sys_getsockname [ 51] } hitcount: 3 + { id: sys_unlink [ 87] } hitcount: 3 + { id: sys_rename [ 82] } hitcount: 4 + { id: unknown_syscall [ 58] } hitcount: 4 + { id: sys_connect [ 42] } hitcount: 4 + { id: sys_getpid [ 39] } hitcount: 4 + . + . + . + { id: sys_rt_sigprocmask [ 14] } hitcount: 952 + { id: sys_futex [202] } hitcount: 1534 + { id: sys_write [ 1] } hitcount: 2689 + { id: sys_setitimer [ 38] } hitcount: 2797 + { id: sys_read [ 0] } hitcount: 3202 + { id: sys_select [ 23] } hitcount: 3773 + { id: sys_writev [ 20] } hitcount: 4531 + { id: sys_poll [ 7] } hitcount: 8314 + { id: sys_recvmsg [ 47] } hitcount: 13738 + { id: sys_ioctl [ 16] } hitcount: 21843 + + Totals: + Hits: 67612 + Entries: 72 + Dropped: 0 + + The syscall counts above provide a rough overall picture of system + call activity on the system; we can see for example that the most + popular system call on this system was the 'sys_ioctl' system call. + + We can use 'compound' keys to refine that number and provide some + further insight as to which processes exactly contribute to the + overall ioctl count. + + The command below keeps a hitcount for every unique combination of + system call id and pid - the end result is essentially a table + that keeps a per-pid sum of system call hits. The results are + sorted using the system call id as the primary key, and the + hitcount sum as the secondary key: + + # echo 'hist:key=id.syscall,common_pid.execname:val=hitcount:sort=id,hitcount' > \ + /sys/kernel/debug/tracing/events/raw_syscalls/sys_enter/trigger + + # cat /sys/kernel/debug/tracing/events/raw_syscalls/sys_enter/hist + # trigger info: hist:keys=id.syscall,common_pid.execname:vals=hitcount:sort=id.syscall,hitcount:size=2048 [active] + + { id: sys_read [ 0], common_pid: rtkit-daemon [ 1877] } hitcount: 1 + { id: sys_read [ 0], common_pid: gdbus [ 2976] } hitcount: 1 + { id: sys_read [ 0], common_pid: console-kit-dae [ 3400] } hitcount: 1 + { id: sys_read [ 0], common_pid: postgres [ 1865] } hitcount: 1 + { id: sys_read [ 0], common_pid: deja-dup-monito [ 3543] } hitcount: 2 + { id: sys_read [ 0], common_pid: NetworkManager [ 890] } hitcount: 2 + { id: sys_read [ 0], common_pid: evolution-calen [ 3048] } hitcount: 2 + { id: sys_read [ 0], common_pid: postgres [ 1864] } hitcount: 2 + { id: sys_read [ 0], common_pid: nm-applet [ 3022] } hitcount: 2 + { id: sys_read [ 0], common_pid: whoopsie [ 1212] } hitcount: 2 + . + . + . + { id: sys_ioctl [ 16], common_pid: bash [ 8479] } hitcount: 1 + { id: sys_ioctl [ 16], common_pid: bash [ 3472] } hitcount: 12 + { id: sys_ioctl [ 16], common_pid: gnome-terminal [ 3199] } hitcount: 16 + { id: sys_ioctl [ 16], common_pid: Xorg [ 1267] } hitcount: 1808 + { id: sys_ioctl [ 16], common_pid: compiz [ 2994] } hitcount: 5580 + . + . + . + { id: sys_waitid [247], common_pid: upstart-dbus-br [ 2690] } hitcount: 3 + { id: sys_waitid [247], common_pid: upstart-dbus-br [ 2688] } hitcount: 16 + { id: sys_inotify_add_watch [254], common_pid: gmain [ 975] } hitcount: 2 + { id: sys_inotify_add_watch [254], common_pid: gmain [ 3204] } hitcount: 4 + { id: sys_inotify_add_watch [254], common_pid: gmain [ 2888] } hitcount: 4 + { id: sys_inotify_add_watch [254], common_pid: gmain [ 3003] } hitcount: 4 + { id: sys_inotify_add_watch [254], common_pid: gmain [ 2873] } hitcount: 4 + { id: sys_inotify_add_watch [254], common_pid: gmain [ 3196] } hitcount: 6 + { id: sys_openat [257], common_pid: java [ 2623] } hitcount: 2 + { id: sys_eventfd2 [290], common_pid: ibus-ui-gtk3 [ 2760] } hitcount: 4 + { id: sys_eventfd2 [290], common_pid: compiz [ 2994] } hitcount: 6 + + Totals: + Hits: 31536 + Entries: 323 + Dropped: 0 + + The above list does give us a breakdown of the ioctl syscall by + pid, but it also gives us quite a bit more than that, which we + don't really care about at the moment. Since we know the syscall + id for sys_ioctl (16, displayed next to the sys_ioctl name), we + can use that to filter out all the other syscalls: + + # echo 'hist:key=id.syscall,common_pid.execname:val=hitcount:sort=id,hitcount if id == 16' > \ + /sys/kernel/debug/tracing/events/raw_syscalls/sys_enter/trigger + + # cat /sys/kernel/debug/tracing/events/raw_syscalls/sys_enter/hist + # trigger info: hist:keys=id.syscall,common_pid.execname:vals=hitcount:sort=id.syscall,hitcount:size=2048 if id == 16 [active] + + { id: sys_ioctl [ 16], common_pid: gmain [ 2769] } hitcount: 1 + { id: sys_ioctl [ 16], common_pid: evolution-addre [ 8571] } hitcount: 1 + { id: sys_ioctl [ 16], common_pid: gmain [ 3003] } hitcount: 1 + { id: sys_ioctl [ 16], common_pid: gmain [ 2781] } hitcount: 1 + { id: sys_ioctl [ 16], common_pid: gmain [ 2829] } hitcount: 1 + { id: sys_ioctl [ 16], common_pid: bash [ 8726] } hitcount: 1 + { id: sys_ioctl [ 16], common_pid: bash [ 8508] } hitcount: 1 + { id: sys_ioctl [ 16], common_pid: gmain [ 2970] } hitcount: 1 + { id: sys_ioctl [ 16], common_pid: gmain [ 2768] } hitcount: 1 + . + . + . + { id: sys_ioctl [ 16], common_pid: pool [ 8559] } hitcount: 45 + { id: sys_ioctl [ 16], common_pid: pool [ 8555] } hitcount: 48 + { id: sys_ioctl [ 16], common_pid: pool [ 8551] } hitcount: 48 + { id: sys_ioctl [ 16], common_pid: avahi-daemon [ 896] } hitcount: 66 + { id: sys_ioctl [ 16], common_pid: Xorg [ 1267] } hitcount: 26674 + { id: sys_ioctl [ 16], common_pid: compiz [ 2994] } hitcount: 73443 + + Totals: + Hits: 101162 + Entries: 103 + Dropped: 0 + + The above output shows that 'compiz' and 'Xorg' are far and away + the heaviest ioctl callers (which might lead to questions about + whether they really need to be making all those calls and to + possible avenues for further investigation.) + + The compound key examples used a key and a sum value (hitcount) to + sort the output, but we can just as easily use two keys instead. + Here's an example where we use a compound key composed of the the + common_pid and size event fields. Sorting with pid as the primary + key and 'size' as the secondary key allows us to display an + ordered summary of the recvfrom sizes, with counts, received by + each process: + + # echo 'hist:key=common_pid.execname,size:val=hitcount:sort=common_pid,size' > \ + /sys/kernel/debug/tracing/events/syscalls/sys_enter_recvfrom/trigger + + # cat /sys/kernel/debug/tracing/events/syscalls/sys_enter_recvfrom/hist + # trigger info: hist:keys=common_pid.execname,size:vals=hitcount:sort=common_pid.execname,size:size=2048 [active] + + { common_pid: smbd [ 784], size: 4 } hitcount: 1 + { common_pid: dnsmasq [ 1412], size: 4096 } hitcount: 672 + { common_pid: postgres [ 1796], size: 1000 } hitcount: 6 + { common_pid: postgres [ 1867], size: 1000 } hitcount: 10 + { common_pid: bamfdaemon [ 2787], size: 28 } hitcount: 2 + { common_pid: bamfdaemon [ 2787], size: 14360 } hitcount: 1 + { common_pid: compiz [ 2994], size: 8 } hitcount: 1 + { common_pid: compiz [ 2994], size: 20 } hitcount: 11 + { common_pid: gnome-terminal [ 3199], size: 4 } hitcount: 2 + { common_pid: firefox [ 8817], size: 4 } hitcount: 1 + { common_pid: firefox [ 8817], size: 8 } hitcount: 5 + { common_pid: firefox [ 8817], size: 588 } hitcount: 2 + { common_pid: firefox [ 8817], size: 628 } hitcount: 1 + { common_pid: firefox [ 8817], size: 6944 } hitcount: 1 + { common_pid: firefox [ 8817], size: 408880 } hitcount: 2 + { common_pid: firefox [ 8822], size: 8 } hitcount: 2 + { common_pid: firefox [ 8822], size: 160 } hitcount: 2 + { common_pid: firefox [ 8822], size: 320 } hitcount: 2 + { common_pid: firefox [ 8822], size: 352 } hitcount: 1 + . + . + . + { common_pid: pool [ 8923], size: 1960 } hitcount: 10 + { common_pid: pool [ 8923], size: 2048 } hitcount: 10 + { common_pid: pool [ 8924], size: 1960 } hitcount: 10 + { common_pid: pool [ 8924], size: 2048 } hitcount: 10 + { common_pid: pool [ 8928], size: 1964 } hitcount: 4 + { common_pid: pool [ 8928], size: 1965 } hitcount: 2 + { common_pid: pool [ 8928], size: 2048 } hitcount: 6 + { common_pid: pool [ 8929], size: 1982 } hitcount: 1 + { common_pid: pool [ 8929], size: 2048 } hitcount: 1 + + Totals: + Hits: 2016 + Entries: 224 + Dropped: 0 + + The above example also illustrates the fact that although a compound + key is treated as a single entity for hashing purposes, the sub-keys + it's composed of can be accessed independently. + + The next example uses a string field as the hash key and + demonstrates how you can manually pause and continue a hist trigger. + In this example, we'll aggregate fork counts and don't expect a + large number of entries in the hash table, so we'll drop it to a + much smaller number, say 256: + + # echo 'hist:key=child_comm:val=hitcount:size=256' > \ + /sys/kernel/debug/tracing/events/sched/sched_process_fork/trigger + + # cat /sys/kernel/debug/tracing/events/sched/sched_process_fork/hist + # trigger info: hist:keys=child_comm:vals=hitcount:sort=hitcount:size=256 [active] + + { child_comm: dconf worker } hitcount: 1 + { child_comm: ibus-daemon } hitcount: 1 + { child_comm: whoopsie } hitcount: 1 + { child_comm: smbd } hitcount: 1 + { child_comm: gdbus } hitcount: 1 + { child_comm: kthreadd } hitcount: 1 + { child_comm: dconf worker } hitcount: 1 + { child_comm: evolution-alarm } hitcount: 2 + { child_comm: Socket Thread } hitcount: 2 + { child_comm: postgres } hitcount: 2 + { child_comm: bash } hitcount: 3 + { child_comm: compiz } hitcount: 3 + { child_comm: evolution-sourc } hitcount: 4 + { child_comm: dhclient } hitcount: 4 + { child_comm: pool } hitcount: 5 + { child_comm: nm-dispatcher.a } hitcount: 8 + { child_comm: firefox } hitcount: 8 + { child_comm: dbus-daemon } hitcount: 8 + { child_comm: glib-pacrunner } hitcount: 10 + { child_comm: evolution } hitcount: 23 + + Totals: + Hits: 89 + Entries: 20 + Dropped: 0 + + If we want to pause the hist trigger, we can simply append :pause to + the command that started the trigger. Notice that the trigger info + displays as [paused]: + + # echo 'hist:key=child_comm:val=hitcount:size=256:pause' >> \ + /sys/kernel/debug/tracing/events/sched/sched_process_fork/trigger + + # cat /sys/kernel/debug/tracing/events/sched/sched_process_fork/hist + # trigger info: hist:keys=child_comm:vals=hitcount:sort=hitcount:size=256 [paused] + + { child_comm: dconf worker } hitcount: 1 + { child_comm: kthreadd } hitcount: 1 + { child_comm: dconf worker } hitcount: 1 + { child_comm: gdbus } hitcount: 1 + { child_comm: ibus-daemon } hitcount: 1 + { child_comm: Socket Thread } hitcount: 2 + { child_comm: evolution-alarm } hitcount: 2 + { child_comm: smbd } hitcount: 2 + { child_comm: bash } hitcount: 3 + { child_comm: whoopsie } hitcount: 3 + { child_comm: compiz } hitcount: 3 + { child_comm: evolution-sourc } hitcount: 4 + { child_comm: pool } hitcount: 5 + { child_comm: postgres } hitcount: 6 + { child_comm: firefox } hitcount: 8 + { child_comm: dhclient } hitcount: 10 + { child_comm: emacs } hitcount: 12 + { child_comm: dbus-daemon } hitcount: 20 + { child_comm: nm-dispatcher.a } hitcount: 20 + { child_comm: evolution } hitcount: 35 + { child_comm: glib-pacrunner } hitcount: 59 + + Totals: + Hits: 199 + Entries: 21 + Dropped: 0 + + To manually continue having the trigger aggregate events, append + :cont instead. Notice that the trigger info displays as [active] + again, and the data has changed: + + # echo 'hist:key=child_comm:val=hitcount:size=256:cont' >> \ + /sys/kernel/debug/tracing/events/sched/sched_process_fork/trigger + + # cat /sys/kernel/debug/tracing/events/sched/sched_process_fork/hist + # trigger info: hist:keys=child_comm:vals=hitcount:sort=hitcount:size=256 [active] + + { child_comm: dconf worker } hitcount: 1 + { child_comm: dconf worker } hitcount: 1 + { child_comm: kthreadd } hitcount: 1 + { child_comm: gdbus } hitcount: 1 + { child_comm: ibus-daemon } hitcount: 1 + { child_comm: Socket Thread } hitcount: 2 + { child_comm: evolution-alarm } hitcount: 2 + { child_comm: smbd } hitcount: 2 + { child_comm: whoopsie } hitcount: 3 + { child_comm: compiz } hitcount: 3 + { child_comm: evolution-sourc } hitcount: 4 + { child_comm: bash } hitcount: 5 + { child_comm: pool } hitcount: 5 + { child_comm: postgres } hitcount: 6 + { child_comm: firefox } hitcount: 8 + { child_comm: dhclient } hitcount: 11 + { child_comm: emacs } hitcount: 12 + { child_comm: dbus-daemon } hitcount: 22 + { child_comm: nm-dispatcher.a } hitcount: 22 + { child_comm: evolution } hitcount: 35 + { child_comm: glib-pacrunner } hitcount: 59 + + Totals: + Hits: 206 + Entries: 21 + Dropped: 0 + + The previous example showed how to start and stop a hist trigger by + appending 'pause' and 'continue' to the hist trigger command. A + hist trigger can also be started in a paused state by initially + starting the trigger with ':pause' appended. This allows you to + start the trigger only when you're ready to start collecting data + and not before. For example, you could start the trigger in a + paused state, then unpause it and do something you want to measure, + then pause the trigger again when done. + + Of course, doing this manually can be difficult and error-prone, but + it is possible to automatically start and stop a hist trigger based + on some condition, via the enable_hist and disable_hist triggers. + + For example, suppose we wanted to take a look at the relative + weights in terms of skb length for each callpath that leads to a + netif_receieve_skb event when downloading a decent-sized file using + wget. + + First we set up an initially paused stacktrace trigger on the + netif_receive_skb event: + + # echo 'hist:key=stacktrace:vals=len:pause' > \ + /sys/kernel/debug/tracing/events/net/netif_receive_skb/trigger + + Next, we set up an 'enable_hist' trigger on the sched_process_exec + event, with an 'if filename==/usr/bin/wget' filter. The effect of + this new trigger is that it will 'unpause' the hist trigger we just + set up on netif_receive_skb if and only if it sees a + sched_process_exec event with a filename of '/usr/bin/wget'. When + that happens, all netif_receive_skb events are aggregated into a + hash table keyed on stacktrace: + + # echo 'enable_hist:net:netif_receive_skb if filename==/usr/bin/wget' > \ + /sys/kernel/debug/tracing/events/sched/sched_process_exec/trigger + + The aggregation continues until the netif_receive_skb is paused + again, which is what the following disable_hist event does by + creating a similar setup on the sched_process_exit event, using the + filter 'comm==wget': + + # echo 'disable_hist:net:netif_receive_skb if comm==wget' > \ + /sys/kernel/debug/tracing/events/sched/sched_process_exit/trigger + + Whenever a process exits and the comm field of the disable_hist + trigger filter matches 'comm==wget', the netif_receive_skb hist + trigger is disabled. + + The overall effect is that netif_receive_skb events are aggregated + into the hash table for only the duration of the wget. Executing a + wget command and then listing the 'hist' file will display the + output generated by the wget command: + + $ wget https://www.kernel.org/pub/linux/kernel/v3.x/patch-3.19.xz + + # cat /sys/kernel/debug/tracing/events/net/netif_receive_skb/hist + # trigger info: hist:keys=stacktrace:vals=len:sort=hitcount:size=2048 [paused] + + { stacktrace: + __netif_receive_skb_core+0x46d/0x990 + __netif_receive_skb+0x18/0x60 + netif_receive_skb_internal+0x23/0x90 + napi_gro_receive+0xc8/0x100 + ieee80211_deliver_skb+0xd6/0x270 [mac80211] + ieee80211_rx_handlers+0xccf/0x22f0 [mac80211] + ieee80211_prepare_and_rx_handle+0x4e7/0xc40 [mac80211] + ieee80211_rx+0x31d/0x900 [mac80211] + iwlagn_rx_reply_rx+0x3db/0x6f0 [iwldvm] + iwl_rx_dispatch+0x8e/0xf0 [iwldvm] + iwl_pcie_irq_handler+0xe3c/0x12f0 [iwlwifi] + irq_thread_fn+0x20/0x50 + irq_thread+0x11f/0x150 + kthread+0xd2/0xf0 + ret_from_fork+0x42/0x70 + } hitcount: 85 len: 28884 + { stacktrace: + __netif_receive_skb_core+0x46d/0x990 + __netif_receive_skb+0x18/0x60 + netif_receive_skb_internal+0x23/0x90 + napi_gro_complete+0xa4/0xe0 + dev_gro_receive+0x23a/0x360 + napi_gro_receive+0x30/0x100 + ieee80211_deliver_skb+0xd6/0x270 [mac80211] + ieee80211_rx_handlers+0xccf/0x22f0 [mac80211] + ieee80211_prepare_and_rx_handle+0x4e7/0xc40 [mac80211] + ieee80211_rx+0x31d/0x900 [mac80211] + iwlagn_rx_reply_rx+0x3db/0x6f0 [iwldvm] + iwl_rx_dispatch+0x8e/0xf0 [iwldvm] + iwl_pcie_irq_handler+0xe3c/0x12f0 [iwlwifi] + irq_thread_fn+0x20/0x50 + irq_thread+0x11f/0x150 + kthread+0xd2/0xf0 + } hitcount: 98 len: 664329 + { stacktrace: + __netif_receive_skb_core+0x46d/0x990 + __netif_receive_skb+0x18/0x60 + process_backlog+0xa8/0x150 + net_rx_action+0x15d/0x340 + __do_softirq+0x114/0x2c0 + do_softirq_own_stack+0x1c/0x30 + do_softirq+0x65/0x70 + __local_bh_enable_ip+0xb5/0xc0 + ip_finish_output+0x1f4/0x840 + ip_output+0x6b/0xc0 + ip_local_out_sk+0x31/0x40 + ip_send_skb+0x1a/0x50 + udp_send_skb+0x173/0x2a0 + udp_sendmsg+0x2bf/0x9f0 + inet_sendmsg+0x64/0xa0 + sock_sendmsg+0x3d/0x50 + } hitcount: 115 len: 13030 + { stacktrace: + __netif_receive_skb_core+0x46d/0x990 + __netif_receive_skb+0x18/0x60 + netif_receive_skb_internal+0x23/0x90 + napi_gro_complete+0xa4/0xe0 + napi_gro_flush+0x6d/0x90 + iwl_pcie_irq_handler+0x92a/0x12f0 [iwlwifi] + irq_thread_fn+0x20/0x50 + irq_thread+0x11f/0x150 + kthread+0xd2/0xf0 + ret_from_fork+0x42/0x70 + } hitcount: 934 len: 5512212 + + Totals: + Hits: 1232 + Entries: 4 + Dropped: 0 + + The above shows all the netif_receive_skb callpaths and their total + lengths for the duration of the wget command. + + The 'clear' hist trigger param can be used to clear the hash table. + Suppose we wanted to try another run of the previous example but + this time also wanted to see the complete list of events that went + into the histogram. In order to avoid having to set everything up + again, we can just clear the histogram first: + + # echo 'hist:key=stacktrace:vals=len:clear' >> \ + /sys/kernel/debug/tracing/events/net/netif_receive_skb/trigger + + Just to verify that it is in fact cleared, here's what we now see in + the hist file: + + # cat /sys/kernel/debug/tracing/events/net/netif_receive_skb/hist + # trigger info: hist:keys=stacktrace:vals=len:sort=hitcount:size=2048 [paused] + + Totals: + Hits: 0 + Entries: 0 + Dropped: 0 + + Since we want to see the detailed list of every netif_receive_skb + event occurring during the new run, which are in fact the same + events being aggregated into the hash table, we add some additional + 'enable_event' events to the triggering sched_process_exec and + sched_process_exit events as such: + + # echo 'enable_event:net:netif_receive_skb if filename==/usr/bin/wget' > \ + /sys/kernel/debug/tracing/events/sched/sched_process_exec/trigger + + # echo 'disable_event:net:netif_receive_skb if comm==wget' > \ + /sys/kernel/debug/tracing/events/sched/sched_process_exit/trigger + + If you read the trigger files for the sched_process_exec and + sched_process_exit triggers, you should see two triggers for each: + one enabling/disabling the hist aggregation and the other + enabling/disabling the logging of events: + + # cat /sys/kernel/debug/tracing/events/sched/sched_process_exec/trigger + enable_event:net:netif_receive_skb:unlimited if filename==/usr/bin/wget + enable_hist:net:netif_receive_skb:unlimited if filename==/usr/bin/wget + + # cat /sys/kernel/debug/tracing/events/sched/sched_process_exit/trigger + enable_event:net:netif_receive_skb:unlimited if comm==wget + disable_hist:net:netif_receive_skb:unlimited if comm==wget + + In other words, whenever either of the sched_process_exec or + sched_process_exit events is hit and matches 'wget', it enables or + disables both the histogram and the event log, and what you end up + with is a hash table and set of events just covering the specified + duration. Run the wget command again: + + $ wget https://www.kernel.org/pub/linux/kernel/v3.x/patch-3.19.xz + + Displaying the 'hist' file should show something similar to what you + saw in the last run, but this time you should also see the + individual events in the trace file: + + # cat /sys/kernel/debug/tracing/trace + + # tracer: nop + # + # entries-in-buffer/entries-written: 183/1426 #P:4 + # + # _-----=> irqs-off + # / _----=> need-resched + # | / _---=> hardirq/softirq + # || / _--=> preempt-depth + # ||| / delay + # TASK-PID CPU# |||| TIMESTAMP FUNCTION + # | | | |||| | | + wget-15108 [000] ..s1 31769.606929: netif_receive_skb: dev=lo skbaddr=ffff88009c353100 len=60 + wget-15108 [000] ..s1 31769.606999: netif_receive_skb: dev=lo skbaddr=ffff88009c353200 len=60 + dnsmasq-1382 [000] ..s1 31769.677652: netif_receive_skb: dev=lo skbaddr=ffff88009c352b00 len=130 + dnsmasq-1382 [000] ..s1 31769.685917: netif_receive_skb: dev=lo skbaddr=ffff88009c352200 len=138 + ##### CPU 2 buffer started #### + irq/29-iwlwifi-559 [002] ..s. 31772.031529: netif_receive_skb: dev=wlan0 skbaddr=ffff88009d433d00 len=2948 + irq/29-iwlwifi-559 [002] ..s. 31772.031572: netif_receive_skb: dev=wlan0 skbaddr=ffff88009d432200 len=1500 + irq/29-iwlwifi-559 [002] ..s. 31772.032196: netif_receive_skb: dev=wlan0 skbaddr=ffff88009d433100 len=2948 + irq/29-iwlwifi-559 [002] ..s. 31772.032761: netif_receive_skb: dev=wlan0 skbaddr=ffff88009d433000 len=2948 + irq/29-iwlwifi-559 [002] ..s. 31772.033220: netif_receive_skb: dev=wlan0 skbaddr=ffff88009d432e00 len=1500 + . + . + . + + The following example demonstrates how multiple hist triggers can be + attached to a given event. This capability can be useful for + creating a set of different summaries derived from the same set of + events, or for comparing the effects of different filters, among + other things. + + # echo 'hist:keys=skbaddr.hex:vals=len if len < 0' >> \ + /sys/kernel/debug/tracing/events/net/netif_receive_skb/trigger + # echo 'hist:keys=skbaddr.hex:vals=len if len > 4096' >> \ + /sys/kernel/debug/tracing/events/net/netif_receive_skb/trigger + # echo 'hist:keys=skbaddr.hex:vals=len if len == 256' >> \ + /sys/kernel/debug/tracing/events/net/netif_receive_skb/trigger + # echo 'hist:keys=skbaddr.hex:vals=len' >> \ + /sys/kernel/debug/tracing/events/net/netif_receive_skb/trigger + # echo 'hist:keys=len:vals=common_preempt_count' >> \ + /sys/kernel/debug/tracing/events/net/netif_receive_skb/trigger + + The above set of commands create four triggers differing only in + their filters, along with a completely different though fairly + nonsensical trigger. Note that in order to append multiple hist + triggers to the same file, you should use the '>>' operator to + append them ('>' will also add the new hist trigger, but will remove + any existing hist triggers beforehand). + + Displaying the contents of the 'hist' file for the event shows the + contents of all five histograms: + + # cat /sys/kernel/debug/tracing/events/net/netif_receive_skb/hist + + # event histogram + # + # trigger info: hist:keys=len:vals=hitcount,common_preempt_count:sort=hitcount:size=2048 [active] + # + + { len: 176 } hitcount: 1 common_preempt_count: 0 + { len: 223 } hitcount: 1 common_preempt_count: 0 + { len: 4854 } hitcount: 1 common_preempt_count: 0 + { len: 395 } hitcount: 1 common_preempt_count: 0 + { len: 177 } hitcount: 1 common_preempt_count: 0 + { len: 446 } hitcount: 1 common_preempt_count: 0 + { len: 1601 } hitcount: 1 common_preempt_count: 0 + . + . + . + { len: 1280 } hitcount: 66 common_preempt_count: 0 + { len: 116 } hitcount: 81 common_preempt_count: 40 + { len: 708 } hitcount: 112 common_preempt_count: 0 + { len: 46 } hitcount: 221 common_preempt_count: 0 + { len: 1264 } hitcount: 458 common_preempt_count: 0 + + Totals: + Hits: 1428 + Entries: 147 + Dropped: 0 + + + # event histogram + # + # trigger info: hist:keys=skbaddr.hex:vals=hitcount,len:sort=hitcount:size=2048 [active] + # + + { skbaddr: ffff8800baee5e00 } hitcount: 1 len: 130 + { skbaddr: ffff88005f3d5600 } hitcount: 1 len: 1280 + { skbaddr: ffff88005f3d4900 } hitcount: 1 len: 1280 + { skbaddr: ffff88009fed6300 } hitcount: 1 len: 115 + { skbaddr: ffff88009fe0ad00 } hitcount: 1 len: 115 + { skbaddr: ffff88008cdb1900 } hitcount: 1 len: 46 + { skbaddr: ffff880064b5ef00 } hitcount: 1 len: 118 + { skbaddr: ffff880044e3c700 } hitcount: 1 len: 60 + { skbaddr: ffff880100065900 } hitcount: 1 len: 46 + { skbaddr: ffff8800d46bd500 } hitcount: 1 len: 116 + { skbaddr: ffff88005f3d5f00 } hitcount: 1 len: 1280 + { skbaddr: ffff880100064700 } hitcount: 1 len: 365 + { skbaddr: ffff8800badb6f00 } hitcount: 1 len: 60 + . + . + . + { skbaddr: ffff88009fe0be00 } hitcount: 27 len: 24677 + { skbaddr: ffff88009fe0a400 } hitcount: 27 len: 23052 + { skbaddr: ffff88009fe0b700 } hitcount: 31 len: 25589 + { skbaddr: ffff88009fe0b600 } hitcount: 32 len: 27326 + { skbaddr: ffff88006a462800 } hitcount: 68 len: 71678 + { skbaddr: ffff88006a463700 } hitcount: 70 len: 72678 + { skbaddr: ffff88006a462b00 } hitcount: 71 len: 77589 + { skbaddr: ffff88006a463600 } hitcount: 73 len: 71307 + { skbaddr: ffff88006a462200 } hitcount: 81 len: 81032 + + Totals: + Hits: 1451 + Entries: 318 + Dropped: 0 + + + # event histogram + # + # trigger info: hist:keys=skbaddr.hex:vals=hitcount,len:sort=hitcount:size=2048 if len == 256 [active] + # + + + Totals: + Hits: 0 + Entries: 0 + Dropped: 0 + + + # event histogram + # + # trigger info: hist:keys=skbaddr.hex:vals=hitcount,len:sort=hitcount:size=2048 if len > 4096 [active] + # + + { skbaddr: ffff88009fd2c300 } hitcount: 1 len: 7212 + { skbaddr: ffff8800d2bcce00 } hitcount: 1 len: 7212 + { skbaddr: ffff8800d2bcd700 } hitcount: 1 len: 7212 + { skbaddr: ffff8800d2bcda00 } hitcount: 1 len: 21492 + { skbaddr: ffff8800ae2e2d00 } hitcount: 1 len: 7212 + { skbaddr: ffff8800d2bcdb00 } hitcount: 1 len: 7212 + { skbaddr: ffff88006a4df500 } hitcount: 1 len: 4854 + { skbaddr: ffff88008ce47b00 } hitcount: 1 len: 18636 + { skbaddr: ffff8800ae2e2200 } hitcount: 1 len: 12924 + { skbaddr: ffff88005f3e1000 } hitcount: 1 len: 4356 + { skbaddr: ffff8800d2bcdc00 } hitcount: 2 len: 24420 + { skbaddr: ffff8800d2bcc200 } hitcount: 2 len: 12996 + + Totals: + Hits: 14 + Entries: 12 + Dropped: 0 + + + # event histogram + # + # trigger info: hist:keys=skbaddr.hex:vals=hitcount,len:sort=hitcount:size=2048 if len < 0 [active] + # + + + Totals: + Hits: 0 + Entries: 0 + Dropped: 0 + + Named triggers can be used to have triggers share a common set of + histogram data. This capability is mostly useful for combining the + output of events generated by tracepoints contained inside inline + functions, but names can be used in a hist trigger on any event. + For example, these two triggers when hit will update the same 'len' + field in the shared 'foo' histogram data: + + # echo 'hist:name=foo:keys=skbaddr.hex:vals=len' > \ + /sys/kernel/debug/tracing/events/net/netif_receive_skb/trigger + # echo 'hist:name=foo:keys=skbaddr.hex:vals=len' > \ + /sys/kernel/debug/tracing/events/net/netif_rx/trigger + + You can see that they're updating common histogram data by reading + each event's hist files at the same time: + + # cat /sys/kernel/debug/tracing/events/net/netif_receive_skb/hist; + cat /sys/kernel/debug/tracing/events/net/netif_rx/hist + + # event histogram + # + # trigger info: hist:name=foo:keys=skbaddr.hex:vals=hitcount,len:sort=hitcount:size=2048 [active] + # + + { skbaddr: ffff88000ad53500 } hitcount: 1 len: 46 + { skbaddr: ffff8800af5a1500 } hitcount: 1 len: 76 + { skbaddr: ffff8800d62a1900 } hitcount: 1 len: 46 + { skbaddr: ffff8800d2bccb00 } hitcount: 1 len: 468 + { skbaddr: ffff8800d3c69900 } hitcount: 1 len: 46 + { skbaddr: ffff88009ff09100 } hitcount: 1 len: 52 + { skbaddr: ffff88010f13ab00 } hitcount: 1 len: 168 + { skbaddr: ffff88006a54f400 } hitcount: 1 len: 46 + { skbaddr: ffff8800d2bcc500 } hitcount: 1 len: 260 + { skbaddr: ffff880064505000 } hitcount: 1 len: 46 + { skbaddr: ffff8800baf24e00 } hitcount: 1 len: 32 + { skbaddr: ffff88009fe0ad00 } hitcount: 1 len: 46 + { skbaddr: ffff8800d3edff00 } hitcount: 1 len: 44 + { skbaddr: ffff88009fe0b400 } hitcount: 1 len: 168 + { skbaddr: ffff8800a1c55a00 } hitcount: 1 len: 40 + { skbaddr: ffff8800d2bcd100 } hitcount: 1 len: 40 + { skbaddr: ffff880064505f00 } hitcount: 1 len: 174 + { skbaddr: ffff8800a8bff200 } hitcount: 1 len: 160 + { skbaddr: ffff880044e3cc00 } hitcount: 1 len: 76 + { skbaddr: ffff8800a8bfe700 } hitcount: 1 len: 46 + { skbaddr: ffff8800d2bcdc00 } hitcount: 1 len: 32 + { skbaddr: ffff8800a1f64800 } hitcount: 1 len: 46 + { skbaddr: ffff8800d2bcde00 } hitcount: 1 len: 988 + { skbaddr: ffff88006a5dea00 } hitcount: 1 len: 46 + { skbaddr: ffff88002e37a200 } hitcount: 1 len: 44 + { skbaddr: ffff8800a1f32c00 } hitcount: 2 len: 676 + { skbaddr: ffff88000ad52600 } hitcount: 2 len: 107 + { skbaddr: ffff8800a1f91e00 } hitcount: 2 len: 92 + { skbaddr: ffff8800af5a0200 } hitcount: 2 len: 142 + { skbaddr: ffff8800d2bcc600 } hitcount: 2 len: 220 + { skbaddr: ffff8800ba36f500 } hitcount: 2 len: 92 + { skbaddr: ffff8800d021f800 } hitcount: 2 len: 92 + { skbaddr: ffff8800a1f33600 } hitcount: 2 len: 675 + { skbaddr: ffff8800a8bfff00 } hitcount: 3 len: 138 + { skbaddr: ffff8800d62a1300 } hitcount: 3 len: 138 + { skbaddr: ffff88002e37a100 } hitcount: 4 len: 184 + { skbaddr: ffff880064504400 } hitcount: 4 len: 184 + { skbaddr: ffff8800a8bfec00 } hitcount: 4 len: 184 + { skbaddr: ffff88000ad53700 } hitcount: 5 len: 230 + { skbaddr: ffff8800d2bcdb00 } hitcount: 5 len: 196 + { skbaddr: ffff8800a1f90000 } hitcount: 6 len: 276 + { skbaddr: ffff88006a54f900 } hitcount: 6 len: 276 + + Totals: + Hits: 81 + Entries: 42 + Dropped: 0 + # event histogram + # + # trigger info: hist:name=foo:keys=skbaddr.hex:vals=hitcount,len:sort=hitcount:size=2048 [active] + # + + { skbaddr: ffff88000ad53500 } hitcount: 1 len: 46 + { skbaddr: ffff8800af5a1500 } hitcount: 1 len: 76 + { skbaddr: ffff8800d62a1900 } hitcount: 1 len: 46 + { skbaddr: ffff8800d2bccb00 } hitcount: 1 len: 468 + { skbaddr: ffff8800d3c69900 } hitcount: 1 len: 46 + { skbaddr: ffff88009ff09100 } hitcount: 1 len: 52 + { skbaddr: ffff88010f13ab00 } hitcount: 1 len: 168 + { skbaddr: ffff88006a54f400 } hitcount: 1 len: 46 + { skbaddr: ffff8800d2bcc500 } hitcount: 1 len: 260 + { skbaddr: ffff880064505000 } hitcount: 1 len: 46 + { skbaddr: ffff8800baf24e00 } hitcount: 1 len: 32 + { skbaddr: ffff88009fe0ad00 } hitcount: 1 len: 46 + { skbaddr: ffff8800d3edff00 } hitcount: 1 len: 44 + { skbaddr: ffff88009fe0b400 } hitcount: 1 len: 168 + { skbaddr: ffff8800a1c55a00 } hitcount: 1 len: 40 + { skbaddr: ffff8800d2bcd100 } hitcount: 1 len: 40 + { skbaddr: ffff880064505f00 } hitcount: 1 len: 174 + { skbaddr: ffff8800a8bff200 } hitcount: 1 len: 160 + { skbaddr: ffff880044e3cc00 } hitcount: 1 len: 76 + { skbaddr: ffff8800a8bfe700 } hitcount: 1 len: 46 + { skbaddr: ffff8800d2bcdc00 } hitcount: 1 len: 32 + { skbaddr: ffff8800a1f64800 } hitcount: 1 len: 46 + { skbaddr: ffff8800d2bcde00 } hitcount: 1 len: 988 + { skbaddr: ffff88006a5dea00 } hitcount: 1 len: 46 + { skbaddr: ffff88002e37a200 } hitcount: 1 len: 44 + { skbaddr: ffff8800a1f32c00 } hitcount: 2 len: 676 + { skbaddr: ffff88000ad52600 } hitcount: 2 len: 107 + { skbaddr: ffff8800a1f91e00 } hitcount: 2 len: 92 + { skbaddr: ffff8800af5a0200 } hitcount: 2 len: 142 + { skbaddr: ffff8800d2bcc600 } hitcount: 2 len: 220 + { skbaddr: ffff8800ba36f500 } hitcount: 2 len: 92 + { skbaddr: ffff8800d021f800 } hitcount: 2 len: 92 + { skbaddr: ffff8800a1f33600 } hitcount: 2 len: 675 + { skbaddr: ffff8800a8bfff00 } hitcount: 3 len: 138 + { skbaddr: ffff8800d62a1300 } hitcount: 3 len: 138 + { skbaddr: ffff88002e37a100 } hitcount: 4 len: 184 + { skbaddr: ffff880064504400 } hitcount: 4 len: 184 + { skbaddr: ffff8800a8bfec00 } hitcount: 4 len: 184 + { skbaddr: ffff88000ad53700 } hitcount: 5 len: 230 + { skbaddr: ffff8800d2bcdb00 } hitcount: 5 len: 196 + { skbaddr: ffff8800a1f90000 } hitcount: 6 len: 276 + { skbaddr: ffff88006a54f900 } hitcount: 6 len: 276 + + Totals: + Hits: 81 + Entries: 42 + Dropped: 0 + + And here's an example that shows how to combine histogram data from + any two events even if they don't share any 'compatible' fields + other than 'hitcount' and 'stacktrace'. These commands create a + couple of triggers named 'bar' using those fields: + + # echo 'hist:name=bar:key=stacktrace:val=hitcount' > \ + /sys/kernel/debug/tracing/events/sched/sched_process_fork/trigger + # echo 'hist:name=bar:key=stacktrace:val=hitcount' > \ + /sys/kernel/debug/tracing/events/net/netif_rx/trigger + + And displaying the output of either shows some interesting if + somewhat confusing output: + + # cat /sys/kernel/debug/tracing/events/sched/sched_process_fork/hist + # cat /sys/kernel/debug/tracing/events/net/netif_rx/hist + + # event histogram + # + # trigger info: hist:name=bar:keys=stacktrace:vals=hitcount:sort=hitcount:size=2048 [active] + # + + { stacktrace: + _do_fork+0x18e/0x330 + kernel_thread+0x29/0x30 + kthreadd+0x154/0x1b0 + ret_from_fork+0x3f/0x70 + } hitcount: 1 + { stacktrace: + netif_rx_internal+0xb2/0xd0 + netif_rx_ni+0x20/0x70 + dev_loopback_xmit+0xaa/0xd0 + ip_mc_output+0x126/0x240 + ip_local_out_sk+0x31/0x40 + igmp_send_report+0x1e9/0x230 + igmp_timer_expire+0xe9/0x120 + call_timer_fn+0x39/0xf0 + run_timer_softirq+0x1e1/0x290 + __do_softirq+0xfd/0x290 + irq_exit+0x98/0xb0 + smp_apic_timer_interrupt+0x4a/0x60 + apic_timer_interrupt+0x6d/0x80 + cpuidle_enter+0x17/0x20 + call_cpuidle+0x3b/0x60 + cpu_startup_entry+0x22d/0x310 + } hitcount: 1 + { stacktrace: + netif_rx_internal+0xb2/0xd0 + netif_rx_ni+0x20/0x70 + dev_loopback_xmit+0xaa/0xd0 + ip_mc_output+0x17f/0x240 + ip_local_out_sk+0x31/0x40 + ip_send_skb+0x1a/0x50 + udp_send_skb+0x13e/0x270 + udp_sendmsg+0x2bf/0x980 + inet_sendmsg+0x67/0xa0 + sock_sendmsg+0x38/0x50 + SYSC_sendto+0xef/0x170 + SyS_sendto+0xe/0x10 + entry_SYSCALL_64_fastpath+0x12/0x6a + } hitcount: 2 + { stacktrace: + netif_rx_internal+0xb2/0xd0 + netif_rx+0x1c/0x60 + loopback_xmit+0x6c/0xb0 + dev_hard_start_xmit+0x219/0x3a0 + __dev_queue_xmit+0x415/0x4f0 + dev_queue_xmit_sk+0x13/0x20 + ip_finish_output2+0x237/0x340 + ip_finish_output+0x113/0x1d0 + ip_output+0x66/0xc0 + ip_local_out_sk+0x31/0x40 + ip_send_skb+0x1a/0x50 + udp_send_skb+0x16d/0x270 + udp_sendmsg+0x2bf/0x980 + inet_sendmsg+0x67/0xa0 + sock_sendmsg+0x38/0x50 + ___sys_sendmsg+0x14e/0x270 + } hitcount: 76 + { stacktrace: + netif_rx_internal+0xb2/0xd0 + netif_rx+0x1c/0x60 + loopback_xmit+0x6c/0xb0 + dev_hard_start_xmit+0x219/0x3a0 + __dev_queue_xmit+0x415/0x4f0 + dev_queue_xmit_sk+0x13/0x20 + ip_finish_output2+0x237/0x340 + ip_finish_output+0x113/0x1d0 + ip_output+0x66/0xc0 + ip_local_out_sk+0x31/0x40 + ip_send_skb+0x1a/0x50 + udp_send_skb+0x16d/0x270 + udp_sendmsg+0x2bf/0x980 + inet_sendmsg+0x67/0xa0 + sock_sendmsg+0x38/0x50 + ___sys_sendmsg+0x269/0x270 + } hitcount: 77 + { stacktrace: + netif_rx_internal+0xb2/0xd0 + netif_rx+0x1c/0x60 + loopback_xmit+0x6c/0xb0 + dev_hard_start_xmit+0x219/0x3a0 + __dev_queue_xmit+0x415/0x4f0 + dev_queue_xmit_sk+0x13/0x20 + ip_finish_output2+0x237/0x340 + ip_finish_output+0x113/0x1d0 + ip_output+0x66/0xc0 + ip_local_out_sk+0x31/0x40 + ip_send_skb+0x1a/0x50 + udp_send_skb+0x16d/0x270 + udp_sendmsg+0x2bf/0x980 + inet_sendmsg+0x67/0xa0 + sock_sendmsg+0x38/0x50 + SYSC_sendto+0xef/0x170 + } hitcount: 88 + { stacktrace: + _do_fork+0x18e/0x330 + SyS_clone+0x19/0x20 + entry_SYSCALL_64_fastpath+0x12/0x6a + } hitcount: 244 + + Totals: + Hits: 489 + Entries: 7 + Dropped: 0 + + +2.2 Inter-event hist triggers +----------------------------- + +Inter-event hist triggers are hist triggers that combine values from +one or more other events and create a histogram using that data. Data +from an inter-event histogram can in turn become the source for +further combined histograms, thus providing a chain of related +histograms, which is important for some applications. + +The most important example of an inter-event quantity that can be used +in this manner is latency, which is simply a difference in timestamps +between two events. Although latency is the most important +inter-event quantity, note that because the support is completely +general across the trace event subsystem, any event field can be used +in an inter-event quantity. + +An example of a histogram that combines data from other histograms +into a useful chain would be a 'wakeupswitch latency' histogram that +combines a 'wakeup latency' histogram and a 'switch latency' +histogram. + +Normally, a hist trigger specification consists of a (possibly +compound) key along with one or more numeric values, which are +continually updated sums associated with that key. A histogram +specification in this case consists of individual key and value +specifications that refer to trace event fields associated with a +single event type. + +The inter-event hist trigger extension allows fields from multiple +events to be referenced and combined into a multi-event histogram +specification. In support of this overall goal, a few enabling +features have been added to the hist trigger support: + + - In order to compute an inter-event quantity, a value from one + event needs to saved and then referenced from another event. This + requires the introduction of support for histogram 'variables'. + + - The computation of inter-event quantities and their combination + require some minimal amount of support for applying simple + expressions to variables (+ and -). + + - A histogram consisting of inter-event quantities isn't logically a + histogram on either event (so having the 'hist' file for either + event host the histogram output doesn't really make sense). To + address the idea that the histogram is associated with a + combination of events, support is added allowing the creation of + 'synthetic' events that are events derived from other events. + These synthetic events are full-fledged events just like any other + and can be used as such, as for instance to create the + 'combination' histograms mentioned previously. + + - A set of 'actions' can be associated with histogram entries - + these can be used to generate the previously mentioned synthetic + events, but can also be used for other purposes, such as for + example saving context when a 'max' latency has been hit. + + - Trace events don't have a 'timestamp' associated with them, but + there is an implicit timestamp saved along with an event in the + underlying ftrace ring buffer. This timestamp is now exposed as a + a synthetic field named 'common_timestamp' which can be used in + histograms as if it were any other event field; it isn't an actual + field in the trace format but rather is a synthesized value that + nonetheless can be used as if it were an actual field. By default + it is in units of nanoseconds; appending '.usecs' to a + common_timestamp field changes the units to microseconds. + +A note on inter-event timestamps: If common_timestamp is used in a +histogram, the trace buffer is automatically switched over to using +absolute timestamps and the "global" trace clock, in order to avoid +bogus timestamp differences with other clocks that aren't coherent +across CPUs. This can be overridden by specifying one of the other +trace clocks instead, using the "clock=XXX" hist trigger attribute, +where XXX is any of the clocks listed in the tracing/trace_clock +pseudo-file. + +These features are described in more detail in the following sections. + +2.2.1 Histogram Variables +------------------------- + +Variables are simply named locations used for saving and retrieving +values between matching events. A 'matching' event is defined as an +event that has a matching key - if a variable is saved for a histogram +entry corresponding to that key, any subsequent event with a matching +key can access that variable. + +A variable's value is normally available to any subsequent event until +it is set to something else by a subsequent event. The one exception +to that rule is that any variable used in an expression is essentially +'read-once' - once it's used by an expression in a subsequent event, +it's reset to its 'unset' state, which means it can't be used again +unless it's set again. This ensures not only that an event doesn't +use an uninitialized variable in a calculation, but that that variable +is used only once and not for any unrelated subsequent match. + +The basic syntax for saving a variable is to simply prefix a unique +variable name not corresponding to any keyword along with an '=' sign +to any event field. + +Either keys or values can be saved and retrieved in this way. This +creates a variable named 'ts0' for a histogram entry with the key +'next_pid': + + # echo 'hist:keys=next_pid:vals=$ts0:ts0=common_timestamp ... >> \ + event/trigger + +The ts0 variable can be accessed by any subsequent event having the +same pid as 'next_pid'. + +Variable references are formed by prepending the variable name with +the '$' sign. Thus for example, the ts0 variable above would be +referenced as '$ts0' in expressions. + +Because 'vals=' is used, the common_timestamp variable value above +will also be summed as a normal histogram value would (though for a +timestamp it makes little sense). + +The below shows that a key value can also be saved in the same way: + + # echo 'hist:timer_pid=common_pid:key=timer_pid ...' >> event/trigger + +If a variable isn't a key variable or prefixed with 'vals=', the +associated event field will be saved in a variable but won't be summed +as a value: + + # echo 'hist:keys=next_pid:ts1=common_timestamp ... >> event/trigger + +Multiple variables can be assigned at the same time. The below would +result in both ts0 and b being created as variables, with both +common_timestamp and field1 additionally being summed as values: + + # echo 'hist:keys=pid:vals=$ts0,$b:ts0=common_timestamp,b=field1 ... >> \ + event/trigger + +Note that variable assignments can appear either preceding or +following their use. The command below behaves identically to the +command above: + + # echo 'hist:keys=pid:ts0=common_timestamp,b=field1:vals=$ts0,$b ... >> \ + event/trigger + +Any number of variables not bound to a 'vals=' prefix can also be +assigned by simply separating them with colons. Below is the same +thing but without the values being summed in the histogram: + + # echo 'hist:keys=pid:ts0=common_timestamp:b=field1 ... >> event/trigger + +Variables set as above can be referenced and used in expressions on +another event. + +For example, here's how a latency can be calculated: + + # echo 'hist:keys=pid,prio:ts0=common_timestamp ... >> event1/trigger + # echo 'hist:keys=next_pid:wakeup_lat=common_timestamp-$ts0 ... >> event2/trigger + +In the first line above, the event's timetamp is saved into the +variable ts0. In the next line, ts0 is subtracted from the second +event's timestamp to produce the latency, which is then assigned into +yet another variable, 'wakeup_lat'. The hist trigger below in turn +makes use of the wakeup_lat variable to compute a combined latency +using the same key and variable from yet another event: + + # echo 'hist:key=pid:wakeupswitch_lat=$wakeup_lat+$switchtime_lat ... >> event3/trigger + +2.2.2 Synthetic Events +---------------------- + +Synthetic events are user-defined events generated from hist trigger +variables or fields associated with one or more other events. Their +purpose is to provide a mechanism for displaying data spanning +multiple events consistent with the existing and already familiar +usage for normal events. + +To define a synthetic event, the user writes a simple specification +consisting of the name of the new event along with one or more +variables and their types, which can be any valid field type, +separated by semicolons, to the tracing/synthetic_events file. + +For instance, the following creates a new event named 'wakeup_latency' +with 3 fields: lat, pid, and prio. Each of those fields is simply a +variable reference to a variable on another event: + + # echo 'wakeup_latency \ + u64 lat; \ + pid_t pid; \ + int prio' >> \ + /sys/kernel/debug/tracing/synthetic_events + +Reading the tracing/synthetic_events file lists all the currently +defined synthetic events, in this case the event defined above: + + # cat /sys/kernel/debug/tracing/synthetic_events + wakeup_latency u64 lat; pid_t pid; int prio + +An existing synthetic event definition can be removed by prepending +the command that defined it with a '!': + + # echo '!wakeup_latency u64 lat pid_t pid int prio' >> \ + /sys/kernel/debug/tracing/synthetic_events + +At this point, there isn't yet an actual 'wakeup_latency' event +instantiated in the event subsytem - for this to happen, a 'hist +trigger action' needs to be instantiated and bound to actual fields +and variables defined on other events (see Section 6.3.3 below). + +Once that is done, an event instance is created, and a histogram can +be defined using it: + + # echo 'hist:keys=pid,prio,lat.log2:sort=pid,lat' >> \ + /sys/kernel/debug/tracing/events/synthetic/wakeup_latency/trigger + +The new event is created under the tracing/events/synthetic/ directory +and looks and behaves just like any other event: + + # ls /sys/kernel/debug/tracing/events/synthetic/wakeup_latency + enable filter format hist id trigger + +Like any other event, once a histogram is enabled for the event, the +output can be displayed by reading the event's 'hist' file. + +2.2.3 Hist trigger 'actions' +---------------------------- + +A hist trigger 'action' is a function that's executed whenever a +histogram entry is added or updated. + +The default 'action' if no special function is explicity specified is +as it always has been, to simply update the set of values associated +with an entry. Some applications, however, may want to perform +additional actions at that point, such as generate another event, or +compare and save a maximum. + +The following additional actions are available. To specify an action +for a given event, simply specify the action between colons in the +hist trigger specification. + + - onmatch(matching.event).<synthetic_event_name>(param list) + + The 'onmatch(matching.event).<synthetic_event_name>(params)' hist + trigger action is invoked whenever an event matches and the + histogram entry would be added or updated. It causes the named + synthetic event to be generated with the values given in the + 'param list'. The result is the generation of a synthetic event + that consists of the values contained in those variables at the + time the invoking event was hit. + + The 'param list' consists of one or more parameters which may be + either variables or fields defined on either the 'matching.event' + or the target event. The variables or fields specified in the + param list may be either fully-qualified or unqualified. If a + variable is specified as unqualified, it must be unique between + the two events. A field name used as a param can be unqualified + if it refers to the target event, but must be fully qualified if + it refers to the matching event. A fully-qualified name is of the + form 'system.event_name.$var_name' or 'system.event_name.field'. + + The 'matching.event' specification is simply the fully qualified + event name of the event that matches the target event for the + onmatch() functionality, in the form 'system.event_name'. + + Finally, the number and type of variables/fields in the 'param + list' must match the number and types of the fields in the + synthetic event being generated. + + As an example the below defines a simple synthetic event and uses + a variable defined on the sched_wakeup_new event as a parameter + when invoking the synthetic event. Here we define the synthetic + event: + + # echo 'wakeup_new_test pid_t pid' >> \ + /sys/kernel/debug/tracing/synthetic_events + + # cat /sys/kernel/debug/tracing/synthetic_events + wakeup_new_test pid_t pid + + The following hist trigger both defines the missing testpid + variable and specifies an onmatch() action that generates a + wakeup_new_test synthetic event whenever a sched_wakeup_new event + occurs, which because of the 'if comm == "cyclictest"' filter only + happens when the executable is cyclictest: + + # echo 'hist:keys=$testpid:testpid=pid:onmatch(sched.sched_wakeup_new).\ + wakeup_new_test($testpid) if comm=="cyclictest"' >> \ + /sys/kernel/debug/tracing/events/sched/sched_wakeup_new/trigger + + Creating and displaying a histogram based on those events is now + just a matter of using the fields and new synthetic event in the + tracing/events/synthetic directory, as usual: + + # echo 'hist:keys=pid:sort=pid' >> \ + /sys/kernel/debug/tracing/events/synthetic/wakeup_new_test/trigger + + Running 'cyclictest' should cause wakeup_new events to generate + wakeup_new_test synthetic events which should result in histogram + output in the wakeup_new_test event's hist file: + + # cat /sys/kernel/debug/tracing/events/synthetic/wakeup_new_test/hist + + A more typical usage would be to use two events to calculate a + latency. The following example uses a set of hist triggers to + produce a 'wakeup_latency' histogram: + + First, we define a 'wakeup_latency' synthetic event: + + # echo 'wakeup_latency u64 lat; pid_t pid; int prio' >> \ + /sys/kernel/debug/tracing/synthetic_events + + Next, we specify that whenever we see a sched_waking event for a + cyclictest thread, save the timestamp in a 'ts0' variable: + + # echo 'hist:keys=$saved_pid:saved_pid=pid:ts0=common_timestamp.usecs \ + if comm=="cyclictest"' >> \ + /sys/kernel/debug/tracing/events/sched/sched_waking/trigger + + Then, when the corresponding thread is actually scheduled onto the + CPU by a sched_switch event, calculate the latency and use that + along with another variable and an event field to generate a + wakeup_latency synthetic event: + + # echo 'hist:keys=next_pid:wakeup_lat=common_timestamp.usecs-$ts0:\ + onmatch(sched.sched_waking).wakeup_latency($wakeup_lat,\ + $saved_pid,next_prio) if next_comm=="cyclictest"' >> \ + /sys/kernel/debug/tracing/events/sched/sched_switch/trigger + + We also need to create a histogram on the wakeup_latency synthetic + event in order to aggregate the generated synthetic event data: + + # echo 'hist:keys=pid,prio,lat:sort=pid,lat' >> \ + /sys/kernel/debug/tracing/events/synthetic/wakeup_latency/trigger + + Finally, once we've run cyclictest to actually generate some + events, we can see the output by looking at the wakeup_latency + synthetic event's hist file: + + # cat /sys/kernel/debug/tracing/events/synthetic/wakeup_latency/hist + + - onmax(var).save(field,.. .) + + The 'onmax(var).save(field,...)' hist trigger action is invoked + whenever the value of 'var' associated with a histogram entry + exceeds the current maximum contained in that variable. + + The end result is that the trace event fields specified as the + onmax.save() params will be saved if 'var' exceeds the current + maximum for that hist trigger entry. This allows context from the + event that exhibited the new maximum to be saved for later + reference. When the histogram is displayed, additional fields + displaying the saved values will be printed. + + As an example the below defines a couple of hist triggers, one for + sched_waking and another for sched_switch, keyed on pid. Whenever + a sched_waking occurs, the timestamp is saved in the entry + corresponding to the current pid, and when the scheduler switches + back to that pid, the timestamp difference is calculated. If the + resulting latency, stored in wakeup_lat, exceeds the current + maximum latency, the values specified in the save() fields are + recoreded: + + # echo 'hist:keys=pid:ts0=common_timestamp.usecs \ + if comm=="cyclictest"' >> \ + /sys/kernel/debug/tracing/events/sched/sched_waking/trigger + + # echo 'hist:keys=next_pid:\ + wakeup_lat=common_timestamp.usecs-$ts0:\ + onmax($wakeup_lat).save(next_comm,prev_pid,prev_prio,prev_comm) \ + if next_comm=="cyclictest"' >> \ + /sys/kernel/debug/tracing/events/sched/sched_switch/trigger + + When the histogram is displayed, the max value and the saved + values corresponding to the max are displayed following the rest + of the fields: + + # cat /sys/kernel/debug/tracing/events/sched/sched_switch/hist + { next_pid: 2255 } hitcount: 239 + common_timestamp-ts0: 0 + max: 27 + next_comm: cyclictest + prev_pid: 0 prev_prio: 120 prev_comm: swapper/1 + + { next_pid: 2256 } hitcount: 2355 + common_timestamp-ts0: 0 + max: 49 next_comm: cyclictest + prev_pid: 0 prev_prio: 120 prev_comm: swapper/0 + + Totals: + Hits: 12970 + Entries: 2 + Dropped: 0 @ arch/Kconfig:20 @ config OPROFILE tristate "OProfile system profiling" depends on PROFILING depends on HAVE_OPROFILE + depends on !PREEMPT_RT_FULL select RING_BUFFER select RING_BUFFER_ALLOW_SWAP help @ arch/alpha/include/asm/spinlock_types.h:5 @ #ifndef _ALPHA_SPINLOCK_TYPES_H #define _ALPHA_SPINLOCK_TYPES_H -#ifndef __LINUX_SPINLOCK_TYPES_H -# error "please don't include this file directly" -#endif - typedef struct { volatile unsigned int lock; } arch_spinlock_t; @ arch/arm/Kconfig:50 @ config ARM select HARDIRQS_SW_RESEND select HAVE_ARCH_AUDITSYSCALL if (AEABI && !OABI_COMPAT) select HAVE_ARCH_BITREVERSE if (CPU_32v7M || CPU_32v7) && !CPU_32v6 - select HAVE_ARCH_JUMP_LABEL if !XIP_KERNEL && !CPU_ENDIAN_BE32 && MMU + select HAVE_ARCH_JUMP_LABEL if !XIP_KERNEL && !CPU_ENDIAN_BE32 && MMU && !PREEMPT_RT_BASE select HAVE_ARCH_KGDB if !CPU_ENDIAN_BE32 && MMU select HAVE_ARCH_MMAP_RND_BITS if MMU select HAVE_ARCH_SECCOMP_FILTER if (AEABI && !OABI_COMPAT) @ arch/arm/Kconfig:91 @ config ARM select HAVE_PERF_EVENTS select HAVE_PERF_REGS select HAVE_PERF_USER_STACK_DUMP + select HAVE_PREEMPT_LAZY select HAVE_RCU_TABLE_FREE if (SMP && ARM_LPAE) select HAVE_REGS_AND_STACK_ACCESS_API select HAVE_SYSCALL_TRACEPOINTS @ arch/arm/Kconfig:2170 @ config NEON config KERNEL_MODE_NEON bool "Support for NEON in kernel mode" - depends on NEON && AEABI + depends on NEON && AEABI && !PREEMPT_RT_BASE help Say Y to include support for NEON in kernel mode. @ arch/arm/configs/at91_dt_defconfig:22 @ CONFIG_ARCH_MULTI_V5=y CONFIG_ARCH_AT91=y CONFIG_SOC_AT91RM9200=y CONFIG_SOC_AT91SAM9=y +# CONFIG_ATMEL_CLOCKSOURCE_PIT is not set CONFIG_AEABI=y CONFIG_UACCESS_WITH_MEMCPY=y CONFIG_ZBOOT_ROM_TEXT=0x0 @ arch/arm/configs/at91_dt_defconfig:68 @ CONFIG_BLK_DEV_LOOP=y CONFIG_BLK_DEV_RAM=y CONFIG_BLK_DEV_RAM_COUNT=4 CONFIG_BLK_DEV_RAM_SIZE=8192 -CONFIG_ATMEL_TCLIB=y CONFIG_ATMEL_SSC=y CONFIG_SCSI=y CONFIG_BLK_DEV_SD=y @ arch/arm/configs/sama5_defconfig:23 @ CONFIG_ARCH_AT91=y CONFIG_SOC_SAMA5D2=y CONFIG_SOC_SAMA5D3=y CONFIG_SOC_SAMA5D4=y +# CONFIG_ATMEL_CLOCKSOURCE_PIT is not set CONFIG_AEABI=y CONFIG_UACCESS_WITH_MEMCPY=y CONFIG_ZBOOT_ROM_TEXT=0x0 @ arch/arm/configs/sama5_defconfig:79 @ CONFIG_BLK_DEV_LOOP=y CONFIG_BLK_DEV_RAM=y CONFIG_BLK_DEV_RAM_COUNT=4 CONFIG_BLK_DEV_RAM_SIZE=8192 -CONFIG_ATMEL_TCLIB=y CONFIG_ATMEL_SSC=y CONFIG_EEPROM_AT24=y CONFIG_SCSI=y @ arch/arm/include/asm/irq.h:26 @ #endif #ifndef __ASSEMBLY__ +#include <linux/cpumask.h> + struct irqaction; struct pt_regs; extern void migrate_irqs(void); @ arch/arm/include/asm/spinlock_types.h:5 @ #ifndef __ASM_SPINLOCK_TYPES_H #define __ASM_SPINLOCK_TYPES_H -#ifndef __LINUX_SPINLOCK_TYPES_H -# error "please don't include this file directly" -#endif - #define TICKET_SHIFT 16 typedef struct { @ arch/arm/include/asm/switch_to.h:7 @ #include <linux/thread_info.h> +#if defined CONFIG_PREEMPT_RT_FULL && defined CONFIG_HIGHMEM +void switch_kmaps(struct task_struct *prev_p, struct task_struct *next_p); +#else +static inline void +switch_kmaps(struct task_struct *prev_p, struct task_struct *next_p) { } +#endif + /* * For v7 SMP cores running a preemptible kernel we may be pre-empted * during a TLB maintenance operation, so execute an inner-shareable dsb @ arch/arm/include/asm/switch_to.h:36 @ extern struct task_struct *__switch_to(struct task_struct *, struct thread_info #define switch_to(prev,next,last) \ do { \ __complete_pending_tlbi(); \ + switch_kmaps(prev, next); \ last = __switch_to(prev,task_thread_info(prev), task_thread_info(next)); \ } while (0) @ arch/arm/include/asm/thread_info.h:52 @ struct cpu_context_save { struct thread_info { unsigned long flags; /* low level flags */ int preempt_count; /* 0 => preemptable, <0 => bug */ + int preempt_lazy_count; /* 0 => preemptable, <0 => bug */ mm_segment_t addr_limit; /* address limit */ struct task_struct *task; /* main task structure */ __u32 cpu; /* cpu */ @ arch/arm/include/asm/thread_info.h:143 @ extern int vfp_restore_user_hwstate(struct user_vfp __user *, #define TIF_SYSCALL_TRACE 4 /* syscall trace active */ #define TIF_SYSCALL_AUDIT 5 /* syscall auditing active */ #define TIF_SYSCALL_TRACEPOINT 6 /* syscall tracepoint instrumentation */ -#define TIF_SECCOMP 7 /* seccomp syscall filtering active */ +#define TIF_SECCOMP 8 /* seccomp syscall filtering active */ +#define TIF_NEED_RESCHED_LAZY 7 #define TIF_NOHZ 12 /* in adaptive nohz mode */ #define TIF_USING_IWMMXT 17 @ arch/arm/include/asm/thread_info.h:154 @ extern int vfp_restore_user_hwstate(struct user_vfp __user *, #define _TIF_SIGPENDING (1 << TIF_SIGPENDING) #define _TIF_NEED_RESCHED (1 << TIF_NEED_RESCHED) #define _TIF_NOTIFY_RESUME (1 << TIF_NOTIFY_RESUME) +#define _TIF_NEED_RESCHED_LAZY (1 << TIF_NEED_RESCHED_LAZY) #define _TIF_UPROBE (1 << TIF_UPROBE) #define _TIF_SYSCALL_TRACE (1 << TIF_SYSCALL_TRACE) #define _TIF_SYSCALL_AUDIT (1 << TIF_SYSCALL_AUDIT) @ arch/arm/include/asm/thread_info.h:170 @ extern int vfp_restore_user_hwstate(struct user_vfp __user *, * Change these and you break ASM code in entry-common.S */ #define _TIF_WORK_MASK (_TIF_NEED_RESCHED | _TIF_SIGPENDING | \ - _TIF_NOTIFY_RESUME | _TIF_UPROBE) + _TIF_NOTIFY_RESUME | _TIF_UPROBE | \ + _TIF_NEED_RESCHED_LAZY) #endif /* __KERNEL__ */ #endif /* __ASM_ARM_THREAD_INFO_H */ @ arch/arm/kernel/asm-offsets.c:70 @ int main(void) BLANK(); DEFINE(TI_FLAGS, offsetof(struct thread_info, flags)); DEFINE(TI_PREEMPT, offsetof(struct thread_info, preempt_count)); + DEFINE(TI_PREEMPT_LAZY, offsetof(struct thread_info, preempt_lazy_count)); DEFINE(TI_ADDR_LIMIT, offsetof(struct thread_info, addr_limit)); DEFINE(TI_TASK, offsetof(struct thread_info, task)); DEFINE(TI_CPU, offsetof(struct thread_info, cpu)); @ arch/arm/kernel/entry-armv.S:219 @ ENDPROC(__dabt_svc) #ifdef CONFIG_PREEMPT ldr r8, [tsk, #TI_PREEMPT] @ get preempt count - ldr r0, [tsk, #TI_FLAGS] @ get flags teq r8, #0 @ if preempt count != 0 + bne 1f @ return from exeption + ldr r0, [tsk, #TI_FLAGS] @ get flags + tst r0, #_TIF_NEED_RESCHED @ if NEED_RESCHED is set + blne svc_preempt @ preempt! + + ldr r8, [tsk, #TI_PREEMPT_LAZY] @ get preempt lazy count + teq r8, #0 @ if preempt lazy count != 0 movne r0, #0 @ force flags to 0 - tst r0, #_TIF_NEED_RESCHED + tst r0, #_TIF_NEED_RESCHED_LAZY blne svc_preempt +1: #endif svc_exit r5, irq = 1 @ return from exception @ arch/arm/kernel/entry-armv.S:245 @ ENDPROC(__irq_svc) 1: bl preempt_schedule_irq @ irq en/disable is done inside ldr r0, [tsk, #TI_FLAGS] @ get new tasks TI_FLAGS tst r0, #_TIF_NEED_RESCHED + bne 1b + tst r0, #_TIF_NEED_RESCHED_LAZY reteq r8 @ go again - b 1b + ldr r0, [tsk, #TI_PREEMPT_LAZY] @ get preempt lazy count + teq r0, #0 @ if preempt lazy count != 0 + beq 1b + ret r8 @ go again + #endif __und_fault: @ arch/arm/kernel/entry-common.S:57 @ saved_pc .req lr cmp r2, #TASK_SIZE blne addr_limit_check_failed ldr r1, [tsk, #TI_FLAGS] @ re-check for syscall tracing - tst r1, #_TIF_SYSCALL_WORK | _TIF_WORK_MASK + tst r1, #((_TIF_SYSCALL_WORK | _TIF_WORK_MASK) & ~_TIF_SECCOMP) + bne fast_work_pending + tst r1, #_TIF_SECCOMP bne fast_work_pending @ arch/arm/kernel/entry-common.S:89 @ ENDPROC(ret_fast_syscall) cmp r2, #TASK_SIZE blne addr_limit_check_failed ldr r1, [tsk, #TI_FLAGS] @ re-check for syscall tracing - tst r1, #_TIF_SYSCALL_WORK | _TIF_WORK_MASK + tst r1, #((_TIF_SYSCALL_WORK | _TIF_WORK_MASK) & ~_TIF_SECCOMP) + bne do_slower_path + tst r1, #_TIF_SECCOMP beq no_work_pending +do_slower_path: UNWIND(.fnend ) ENDPROC(ret_fast_syscall) @ arch/arm/kernel/patch.c:19 @ struct patch { unsigned int insn; }; -static DEFINE_SPINLOCK(patch_lock); +static DEFINE_RAW_SPINLOCK(patch_lock); static void __kprobes *patch_map(void *addr, int fixmap, unsigned long *flags) __acquires(&patch_lock) @ arch/arm/kernel/patch.c:36 @ static void __kprobes *patch_map(void *addr, int fixmap, unsigned long *flags) return addr; if (flags) - spin_lock_irqsave(&patch_lock, *flags); + raw_spin_lock_irqsave(&patch_lock, *flags); else __acquire(&patch_lock); @ arch/arm/kernel/patch.c:51 @ static void __kprobes patch_unmap(int fixmap, unsigned long *flags) clear_fixmap(fixmap); if (flags) - spin_unlock_irqrestore(&patch_lock, *flags); + raw_spin_unlock_irqrestore(&patch_lock, *flags); else __release(&patch_lock); } @ arch/arm/kernel/process.c:327 @ unsigned long arch_randomize_brk(struct mm_struct *mm) } #ifdef CONFIG_MMU +/* + * CONFIG_SPLIT_PTLOCK_CPUS results in a page->ptl lock. If the lock is not + * initialized by pgtable_page_ctor() then a coredump of the vector page will + * fail. + */ +static int __init vectors_user_mapping_init_page(void) +{ + struct page *page; + unsigned long addr = 0xffff0000; + pgd_t *pgd; + pud_t *pud; + pmd_t *pmd; + + pgd = pgd_offset_k(addr); + pud = pud_offset(pgd, addr); + pmd = pmd_offset(pud, addr); + page = pmd_page(*(pmd)); + + pgtable_page_ctor(page); + + return 0; +} +late_initcall(vectors_user_mapping_init_page); + #ifdef CONFIG_KUSER_HELPERS /* * The vectors page is always readable from user space for the @ arch/arm/kernel/signal.c:641 @ do_work_pending(struct pt_regs *regs, unsigned int thread_flags, int syscall) */ trace_hardirqs_off(); do { - if (likely(thread_flags & _TIF_NEED_RESCHED)) { + if (likely(thread_flags & (_TIF_NEED_RESCHED | + _TIF_NEED_RESCHED_LAZY))) { schedule(); } else { if (unlikely(!user_mode(regs))) @ arch/arm/kernel/smp.c:239 @ int __cpu_disable(void) flush_cache_louis(); local_flush_tlb_all(); - clear_tasks_mm_cpumask(cpu); - return 0; } @ arch/arm/kernel/smp.c:256 @ void __cpu_die(unsigned int cpu) } pr_debug("CPU%u: shutdown\n", cpu); + clear_tasks_mm_cpumask(cpu); /* * platform_cpu_kill() is generally expected to do the powering off * and/or cutting of clocks to the dying CPU. Optionally, this may @ arch/arm/kernel/unwind.c:96 @ extern const struct unwind_idx __start_unwind_idx[]; static const struct unwind_idx *__origin_unwind_idx; extern const struct unwind_idx __stop_unwind_idx[]; -static DEFINE_SPINLOCK(unwind_lock); +static DEFINE_RAW_SPINLOCK(unwind_lock); static LIST_HEAD(unwind_tables); /* Convert a prel31 symbol to an absolute address */ @ arch/arm/kernel/unwind.c:204 @ static const struct unwind_idx *unwind_find_idx(unsigned long addr) /* module unwind tables */ struct unwind_table *table; - spin_lock_irqsave(&unwind_lock, flags); + raw_spin_lock_irqsave(&unwind_lock, flags); list_for_each_entry(table, &unwind_tables, list) { if (addr >= table->begin_addr && addr < table->end_addr) { @ arch/arm/kernel/unwind.c:216 @ static const struct unwind_idx *unwind_find_idx(unsigned long addr) break; } } - spin_unlock_irqrestore(&unwind_lock, flags); + raw_spin_unlock_irqrestore(&unwind_lock, flags); } pr_debug("%s: idx = %p\n", __func__, idx); @ arch/arm/kernel/unwind.c:532 @ struct unwind_table *unwind_table_add(unsigned long start, unsigned long size, tab->begin_addr = text_addr; tab->end_addr = text_addr + text_size; - spin_lock_irqsave(&unwind_lock, flags); + raw_spin_lock_irqsave(&unwind_lock, flags); list_add_tail(&tab->list, &unwind_tables); - spin_unlock_irqrestore(&unwind_lock, flags); + raw_spin_unlock_irqrestore(&unwind_lock, flags); return tab; } @ arch/arm/kernel/unwind.c:546 @ void unwind_table_del(struct unwind_table *tab) if (!tab) return; - spin_lock_irqsave(&unwind_lock, flags); + raw_spin_lock_irqsave(&unwind_lock, flags); list_del(&tab->list); - spin_unlock_irqrestore(&unwind_lock, flags); + raw_spin_unlock_irqrestore(&unwind_lock, flags); kfree(tab); } @ arch/arm/mach-at91/Kconfig:109 @ config SOC_AT91SAM9 AT91SAM9X35 AT91SAM9XE +comment "Clocksource driver selection" + +config ATMEL_CLOCKSOURCE_PIT + bool "Periodic Interval Timer (PIT) support" + depends on SOC_AT91SAM9 || SOC_SAMA5 + default SOC_AT91SAM9 || SOC_SAMA5 + select ATMEL_PIT + help + Select this to get a clocksource based on the Atmel Periodic Interval + Timer. It has a relatively low resolution and the TC Block clocksource + should be preferred. + +config ATMEL_CLOCKSOURCE_TCB + bool "Timer Counter Blocks (TCB) support" + depends on SOC_AT91RM9200 || SOC_AT91SAM9 || SOC_SAMA5 || COMPILE_TEST + default SOC_AT91RM9200 || SOC_AT91SAM9 || SOC_SAMA5 + depends on !ATMEL_TCLIB + select ATMEL_ARM_TCB_CLKSRC + help + Select this to get a high precision clocksource based on a + TC block with a 5+ MHz base clock rate. + On platforms with 16-bit counters, two timer channels are combined + to make a single 32-bit timer. + It can also be used as a clock event device supporting oneshot mode. + config HAVE_AT91_UTMI bool @ arch/arm/mach-exynos/platsmp.c:227 @ static void __iomem *scu_base_addr(void) return (void __iomem *)(S5P_VA_SCU); } -static DEFINE_SPINLOCK(boot_lock); +static DEFINE_RAW_SPINLOCK(boot_lock); static void exynos_secondary_init(unsigned int cpu) { @ arch/arm/mach-exynos/platsmp.c:240 @ static void exynos_secondary_init(unsigned int cpu) /* * Synchronise with the boot thread. */ - spin_lock(&boot_lock); - spin_unlock(&boot_lock); + raw_spin_lock(&boot_lock); + raw_spin_unlock(&boot_lock); } int exynos_set_boot_addr(u32 core_id, unsigned long boot_addr) @ arch/arm/mach-exynos/platsmp.c:305 @ static int exynos_boot_secondary(unsigned int cpu, struct task_struct *idle) * Set synchronisation state between this boot processor * and the secondary one */ - spin_lock(&boot_lock); + raw_spin_lock(&boot_lock); /* * The secondary processor is waiting to be released from @ arch/arm/mach-exynos/platsmp.c:332 @ static int exynos_boot_secondary(unsigned int cpu, struct task_struct *idle) if (timeout == 0) { printk(KERN_ERR "cpu1 power enable failed"); - spin_unlock(&boot_lock); + raw_spin_unlock(&boot_lock); return -ETIMEDOUT; } } @ arch/arm/mach-exynos/platsmp.c:378 @ static int exynos_boot_secondary(unsigned int cpu, struct task_struct *idle) * calibrations, then wait for it to finish */ fail: - spin_unlock(&boot_lock); + raw_spin_unlock(&boot_lock); return pen_release != -1 ? ret : 0; } @ arch/arm/mach-hisi/platmcpm.c:64 @ static void __iomem *sysctrl, *fabric; static int hip04_cpu_table[HIP04_MAX_CLUSTERS][HIP04_MAX_CPUS_PER_CLUSTER]; -static DEFINE_SPINLOCK(boot_lock); +static DEFINE_RAW_SPINLOCK(boot_lock); static u32 fabric_phys_addr; /* * [0]: bootwrapper physical address @ arch/arm/mach-hisi/platmcpm.c:116 @ static int hip04_boot_secondary(unsigned int l_cpu, struct task_struct *idle) if (cluster >= HIP04_MAX_CLUSTERS || cpu >= HIP04_MAX_CPUS_PER_CLUSTER) return -EINVAL; - spin_lock_irq(&boot_lock); + raw_spin_lock_irq(&boot_lock); if (hip04_cpu_table[cluster][cpu]) goto out; @ arch/arm/mach-hisi/platmcpm.c:150 @ static int hip04_boot_secondary(unsigned int l_cpu, struct task_struct *idle) out: hip04_cpu_table[cluster][cpu]++; - spin_unlock_irq(&boot_lock); + raw_spin_unlock_irq(&boot_lock); return 0; } @ arch/arm/mach-hisi/platmcpm.c:165 @ static void hip04_cpu_die(unsigned int l_cpu) cpu = MPIDR_AFFINITY_LEVEL(mpidr, 0); cluster = MPIDR_AFFINITY_LEVEL(mpidr, 1); - spin_lock(&boot_lock); + raw_spin_lock(&boot_lock); hip04_cpu_table[cluster][cpu]--; if (hip04_cpu_table[cluster][cpu] == 1) { /* A power_up request went ahead of us. */ - spin_unlock(&boot_lock); + raw_spin_unlock(&boot_lock); return; } else if (hip04_cpu_table[cluster][cpu] > 1) { pr_err("Cluster %d CPU%d boots multiple times\n", cluster, cpu); @ arch/arm/mach-hisi/platmcpm.c:177 @ static void hip04_cpu_die(unsigned int l_cpu) } last_man = hip04_cluster_is_down(cluster); - spin_unlock(&boot_lock); + raw_spin_unlock(&boot_lock); if (last_man) { /* Since it's Cortex A15, disable L2 prefetching. */ asm volatile( @ arch/arm/mach-hisi/platmcpm.c:206 @ static int hip04_cpu_kill(unsigned int l_cpu) cpu >= HIP04_MAX_CPUS_PER_CLUSTER); count = TIMEOUT_MSEC / POLL_MSEC; - spin_lock_irq(&boot_lock); + raw_spin_lock_irq(&boot_lock); for (tries = 0; tries < count; tries++) { if (hip04_cpu_table[cluster][cpu]) goto err; @ arch/arm/mach-hisi/platmcpm.c:214 @ static int hip04_cpu_kill(unsigned int l_cpu) data = readl_relaxed(sysctrl + SC_CPU_RESET_STATUS(cluster)); if (data & CORE_WFI_STATUS(cpu)) break; - spin_unlock_irq(&boot_lock); + raw_spin_unlock_irq(&boot_lock); /* Wait for clean L2 when the whole cluster is down. */ msleep(POLL_MSEC); - spin_lock_irq(&boot_lock); + raw_spin_lock_irq(&boot_lock); } if (tries >= count) goto err; @ arch/arm/mach-hisi/platmcpm.c:234 @ static int hip04_cpu_kill(unsigned int l_cpu) goto err; if (hip04_cluster_is_down(cluster)) hip04_set_snoop_filter(cluster, 0); - spin_unlock_irq(&boot_lock); + raw_spin_unlock_irq(&boot_lock); return 1; err: - spin_unlock_irq(&boot_lock); + raw_spin_unlock_irq(&boot_lock); return 0; } #endif @ arch/arm/mach-omap2/omap-smp.c:72 @ static const struct omap_smp_config omap5_cfg __initconst = { .startup_addr = omap5_secondary_startup, }; -static DEFINE_SPINLOCK(boot_lock); +static DEFINE_RAW_SPINLOCK(boot_lock); void __iomem *omap4_get_scu_base(void) { @ arch/arm/mach-omap2/omap-smp.c:139 @ static void omap4_secondary_init(unsigned int cpu) /* * Synchronise with the boot thread. */ - spin_lock(&boot_lock); - spin_unlock(&boot_lock); + raw_spin_lock(&boot_lock); + raw_spin_unlock(&boot_lock); } static int omap4_boot_secondary(unsigned int cpu, struct task_struct *idle) @ arch/arm/mach-omap2/omap-smp.c:153 @ static int omap4_boot_secondary(unsigned int cpu, struct task_struct *idle) * Set synchronisation state between this boot processor * and the secondary one */ - spin_lock(&boot_lock); + raw_spin_lock(&boot_lock); /* * Update the AuxCoreBoot0 with boot state for secondary core. @ arch/arm/mach-omap2/omap-smp.c:232 @ static int omap4_boot_secondary(unsigned int cpu, struct task_struct *idle) * Now the secondary core is starting up let it run its * calibrations, then wait for it to finish */ - spin_unlock(&boot_lock); + raw_spin_unlock(&boot_lock); return 0; } @ arch/arm/mach-prima2/platsmp.c:25 @ static void __iomem *clk_base; -static DEFINE_SPINLOCK(boot_lock); +static DEFINE_RAW_SPINLOCK(boot_lock); static void sirfsoc_secondary_init(unsigned int cpu) { @ arch/arm/mach-prima2/platsmp.c:39 @ static void sirfsoc_secondary_init(unsigned int cpu) /* * Synchronise with the boot thread. */ - spin_lock(&boot_lock); - spin_unlock(&boot_lock); + raw_spin_lock(&boot_lock); + raw_spin_unlock(&boot_lock); } static const struct of_device_id clk_ids[] = { @ arch/arm/mach-prima2/platsmp.c:78 @ static int sirfsoc_boot_secondary(unsigned int cpu, struct task_struct *idle) /* make sure write buffer is drained */ mb(); - spin_lock(&boot_lock); + raw_spin_lock(&boot_lock); /* * The secondary processor is waiting to be released from @ arch/arm/mach-prima2/platsmp.c:110 @ static int sirfsoc_boot_secondary(unsigned int cpu, struct task_struct *idle) * now the secondary core is starting up let it run its * calibrations, then wait for it to finish */ - spin_unlock(&boot_lock); + raw_spin_unlock(&boot_lock); return pen_release != -1 ? -ENOSYS : 0; } @ arch/arm/mach-qcom/platsmp.c:49 @ extern void secondary_startup_arm(void); -static DEFINE_SPINLOCK(boot_lock); +static DEFINE_RAW_SPINLOCK(boot_lock); #ifdef CONFIG_HOTPLUG_CPU static void qcom_cpu_die(unsigned int cpu) @ arch/arm/mach-qcom/platsmp.c:63 @ static void qcom_secondary_init(unsigned int cpu) /* * Synchronise with the boot thread. */ - spin_lock(&boot_lock); - spin_unlock(&boot_lock); + raw_spin_lock(&boot_lock); + raw_spin_unlock(&boot_lock); } static int scss_release_secondary(unsigned int cpu) @ arch/arm/mach-qcom/platsmp.c:287 @ static int qcom_boot_secondary(unsigned int cpu, int (*func)(unsigned int)) * set synchronisation state between this boot processor * and the secondary one */ - spin_lock(&boot_lock); + raw_spin_lock(&boot_lock); /* * Send the secondary CPU a soft interrupt, thereby causing @ arch/arm/mach-qcom/platsmp.c:300 @ static int qcom_boot_secondary(unsigned int cpu, int (*func)(unsigned int)) * now the secondary core is starting up let it run its * calibrations, then wait for it to finish */ - spin_unlock(&boot_lock); + raw_spin_unlock(&boot_lock); return ret; } @ arch/arm/mach-spear/platsmp.c:35 @ static void write_pen_release(int val) sync_cache_w(&pen_release); } -static DEFINE_SPINLOCK(boot_lock); +static DEFINE_RAW_SPINLOCK(boot_lock); static void __iomem *scu_base = IOMEM(VA_SCU_BASE); @ arch/arm/mach-spear/platsmp.c:50 @ static void spear13xx_secondary_init(unsigned int cpu) /* * Synchronise with the boot thread. */ - spin_lock(&boot_lock); - spin_unlock(&boot_lock); + raw_spin_lock(&boot_lock); + raw_spin_unlock(&boot_lock); } static int spear13xx_boot_secondary(unsigned int cpu, struct task_struct *idle) @ arch/arm/mach-spear/platsmp.c:62 @ static int spear13xx_boot_secondary(unsigned int cpu, struct task_struct *idle) * set synchronisation state between this boot processor * and the secondary one */ - spin_lock(&boot_lock); + raw_spin_lock(&boot_lock); /* * The secondary processor is waiting to be released from @ arch/arm/mach-spear/platsmp.c:87 @ static int spear13xx_boot_secondary(unsigned int cpu, struct task_struct *idle) * now the secondary core is starting up let it run its * calibrations, then wait for it to finish */ - spin_unlock(&boot_lock); + raw_spin_unlock(&boot_lock); return pen_release != -1 ? -ENOSYS : 0; } @ arch/arm/mach-sti/platsmp.c:38 @ static void write_pen_release(int val) sync_cache_w(&pen_release); } -static DEFINE_SPINLOCK(boot_lock); +static DEFINE_RAW_SPINLOCK(boot_lock); static void sti_secondary_init(unsigned int cpu) { @ arch/arm/mach-sti/platsmp.c:51 @ static void sti_secondary_init(unsigned int cpu) /* * Synchronise with the boot thread. */ - spin_lock(&boot_lock); - spin_unlock(&boot_lock); + raw_spin_lock(&boot_lock); + raw_spin_unlock(&boot_lock); } static int sti_boot_secondary(unsigned int cpu, struct task_struct *idle) @ arch/arm/mach-sti/platsmp.c:63 @ static int sti_boot_secondary(unsigned int cpu, struct task_struct *idle) * set synchronisation state between this boot processor * and the secondary one */ - spin_lock(&boot_lock); + raw_spin_lock(&boot_lock); /* * The secondary processor is waiting to be released from @ arch/arm/mach-sti/platsmp.c:94 @ static int sti_boot_secondary(unsigned int cpu, struct task_struct *idle) * now the secondary core is starting up let it run its * calibrations, then wait for it to finish */ - spin_unlock(&boot_lock); + raw_spin_unlock(&boot_lock); return pen_release != -1 ? -ENOSYS : 0; } @ arch/arm/mm/fault.c:436 @ do_translation_fault(unsigned long addr, unsigned int fsr, if (addr < TASK_SIZE) return do_page_fault(addr, fsr, regs); + if (interrupts_enabled(regs)) + local_irq_enable(); + if (user_mode(regs)) goto bad_area; @ arch/arm/mm/fault.c:506 @ do_translation_fault(unsigned long addr, unsigned int fsr, static int do_sect_fault(unsigned long addr, unsigned int fsr, struct pt_regs *regs) { + if (interrupts_enabled(regs)) + local_irq_enable(); + do_bad_area(addr, fsr, regs); return 0; } @ arch/arm/mm/highmem.c:37 @ static inline pte_t get_fixmap_pte(unsigned long vaddr) return *ptep; } +static unsigned int fixmap_idx(int type) +{ + return FIX_KMAP_BEGIN + type + KM_TYPE_NR * smp_processor_id(); +} + void *kmap(struct page *page) { might_sleep(); @ arch/arm/mm/highmem.c:62 @ EXPORT_SYMBOL(kunmap); void *kmap_atomic(struct page *page) { + pte_t pte = mk_pte(page, kmap_prot); unsigned int idx; unsigned long vaddr; void *kmap; int type; - preempt_disable(); + preempt_disable_nort(); pagefault_disable(); if (!PageHighMem(page)) return page_address(page); @ arch/arm/mm/highmem.c:88 @ void *kmap_atomic(struct page *page) type = kmap_atomic_idx_push(); - idx = FIX_KMAP_BEGIN + type + KM_TYPE_NR * smp_processor_id(); + idx = fixmap_idx(type); vaddr = __fix_to_virt(idx); #ifdef CONFIG_DEBUG_HIGHMEM /* @ arch/arm/mm/highmem.c:102 @ void *kmap_atomic(struct page *page) * in place, so the contained TLB flush ensures the TLB is updated * with the new mapping. */ - set_fixmap_pte(idx, mk_pte(page, kmap_prot)); +#ifdef CONFIG_PREEMPT_RT_FULL + current->kmap_pte[type] = pte; +#endif + set_fixmap_pte(idx, pte); return (void *)vaddr; } @ arch/arm/mm/highmem.c:118 @ void __kunmap_atomic(void *kvaddr) if (kvaddr >= (void *)FIXADDR_START) { type = kmap_atomic_idx(); - idx = FIX_KMAP_BEGIN + type + KM_TYPE_NR * smp_processor_id(); + idx = fixmap_idx(type); if (cache_is_vivt()) __cpuc_flush_dcache_area((void *)vaddr, PAGE_SIZE); +#ifdef CONFIG_PREEMPT_RT_FULL + current->kmap_pte[type] = __pte(0); +#endif #ifdef CONFIG_DEBUG_HIGHMEM BUG_ON(vaddr != __fix_to_virt(idx)); - set_fixmap_pte(idx, __pte(0)); #else (void) idx; /* to kill a warning */ #endif + set_fixmap_pte(idx, __pte(0)); kmap_atomic_idx_pop(); } else if (vaddr >= PKMAP_ADDR(0) && vaddr < PKMAP_ADDR(LAST_PKMAP)) { /* this address was obtained through kmap_high_get() */ kunmap_high(pte_page(pkmap_page_table[PKMAP_NR(vaddr)])); } pagefault_enable(); - preempt_enable(); + preempt_enable_nort(); } EXPORT_SYMBOL(__kunmap_atomic); void *kmap_atomic_pfn(unsigned long pfn) { + pte_t pte = pfn_pte(pfn, kmap_prot); unsigned long vaddr; int idx, type; struct page *page = pfn_to_page(pfn); - preempt_disable(); + preempt_disable_nort(); pagefault_disable(); if (!PageHighMem(page)) return page_address(page); type = kmap_atomic_idx_push(); - idx = FIX_KMAP_BEGIN + type + KM_TYPE_NR * smp_processor_id(); + idx = fixmap_idx(type); vaddr = __fix_to_virt(idx); #ifdef CONFIG_DEBUG_HIGHMEM BUG_ON(!pte_none(get_fixmap_pte(vaddr))); #endif - set_fixmap_pte(idx, pfn_pte(pfn, kmap_prot)); +#ifdef CONFIG_PREEMPT_RT_FULL + current->kmap_pte[type] = pte; +#endif + set_fixmap_pte(idx, pte); return (void *)vaddr; } +#if defined CONFIG_PREEMPT_RT_FULL +void switch_kmaps(struct task_struct *prev_p, struct task_struct *next_p) +{ + int i; + + /* + * Clear @prev's kmap_atomic mappings + */ + for (i = 0; i < prev_p->kmap_idx; i++) { + int idx = fixmap_idx(i); + + set_fixmap_pte(idx, __pte(0)); + } + /* + * Restore @next_p's kmap_atomic mappings + */ + for (i = 0; i < next_p->kmap_idx; i++) { + int idx = fixmap_idx(i); + + if (!pte_none(next_p->kmap_pte[i])) + set_fixmap_pte(idx, next_p->kmap_pte[i]); + } +} +#endif @ arch/arm/plat-versatile/platsmp.c:35 @ static void write_pen_release(int val) sync_cache_w(&pen_release); } -static DEFINE_SPINLOCK(boot_lock); +static DEFINE_RAW_SPINLOCK(boot_lock); void versatile_secondary_init(unsigned int cpu) { @ arch/arm/plat-versatile/platsmp.c:48 @ void versatile_secondary_init(unsigned int cpu) /* * Synchronise with the boot thread. */ - spin_lock(&boot_lock); - spin_unlock(&boot_lock); + raw_spin_lock(&boot_lock); + raw_spin_unlock(&boot_lock); } int versatile_boot_secondary(unsigned int cpu, struct task_struct *idle) @ arch/arm/plat-versatile/platsmp.c:60 @ int versatile_boot_secondary(unsigned int cpu, struct task_struct *idle) * Set synchronisation state between this boot processor * and the secondary one */ - spin_lock(&boot_lock); + raw_spin_lock(&boot_lock); /* * This is really belt and braces; we hold unintended secondary @ arch/arm/plat-versatile/platsmp.c:90 @ int versatile_boot_secondary(unsigned int cpu, struct task_struct *idle) * now the secondary core is starting up let it run its * calibrations, then wait for it to finish */ - spin_unlock(&boot_lock); + raw_spin_unlock(&boot_lock); return pen_release != -1 ? -ENOSYS : 0; } @ arch/arm64/Kconfig:126 @ config ARM64 select HAVE_PERF_EVENTS select HAVE_PERF_REGS select HAVE_PERF_USER_STACK_DUMP + select HAVE_PREEMPT_LAZY select HAVE_REGS_AND_STACK_ACCESS_API select HAVE_RCU_TABLE_FREE select HAVE_SYSCALL_TRACEPOINTS @ arch/arm64/Kconfig:864 @ config XEN_DOM0 config XEN bool "Xen guest support on ARM64" - depends on ARM64 && OF + depends on ARM64 && OF && !PREEMPT_RT_FULL select SWIOTLB_XEN select PARAVIRT help @ arch/arm64/crypto/Kconfig:22 @ config CRYPTO_SHA512_ARM64 config CRYPTO_SHA1_ARM64_CE tristate "SHA-1 digest algorithm (ARMv8 Crypto Extensions)" - depends on KERNEL_MODE_NEON + depends on KERNEL_MODE_NEON && !PREEMPT_RT_BASE select CRYPTO_HASH select CRYPTO_SHA1 config CRYPTO_SHA2_ARM64_CE tristate "SHA-224/SHA-256 digest algorithm (ARMv8 Crypto Extensions)" - depends on KERNEL_MODE_NEON + depends on KERNEL_MODE_NEON && !PREEMPT_RT_BASE select CRYPTO_HASH select CRYPTO_SHA256_ARM64 config CRYPTO_SHA512_ARM64_CE tristate "SHA-384/SHA-512 digest algorithm (ARMv8 Crypto Extensions)" - depends on KERNEL_MODE_NEON + depends on KERNEL_MODE_NEON && !PREEMPT_RT_BASE select CRYPTO_HASH select CRYPTO_SHA512_ARM64 config CRYPTO_SHA3_ARM64 tristate "SHA3 digest algorithm (ARMv8.2 Crypto Extensions)" - depends on KERNEL_MODE_NEON + depends on KERNEL_MODE_NEON && !PREEMPT_RT_BASE select CRYPTO_HASH select CRYPTO_SHA3 config CRYPTO_SM3_ARM64_CE tristate "SM3 digest algorithm (ARMv8.2 Crypto Extensions)" - depends on KERNEL_MODE_NEON + depends on KERNEL_MODE_NEON && !PREEMPT_RT_BASE select CRYPTO_HASH select CRYPTO_SM3 config CRYPTO_GHASH_ARM64_CE tristate "GHASH/AES-GCM using ARMv8 Crypto Extensions" - depends on KERNEL_MODE_NEON + depends on KERNEL_MODE_NEON && !PREEMPT_RT_BASE select CRYPTO_HASH select CRYPTO_GF128MUL select CRYPTO_AES @ arch/arm64/crypto/Kconfig:60 @ config CRYPTO_GHASH_ARM64_CE config CRYPTO_CRCT10DIF_ARM64_CE tristate "CRCT10DIF digest algorithm using PMULL instructions" - depends on KERNEL_MODE_NEON && CRC_T10DIF + depends on KERNEL_MODE_NEON && CRC_T10DIF && !PREEMPT_RT_BASE select CRYPTO_HASH config CRYPTO_CRC32_ARM64_CE @ arch/arm64/crypto/Kconfig:74 @ config CRYPTO_AES_ARM64 config CRYPTO_AES_ARM64_CE tristate "AES core cipher using ARMv8 Crypto Extensions" - depends on ARM64 && KERNEL_MODE_NEON + depends on ARM64 && KERNEL_MODE_NEON && !PREEMPT_RT_BASE select CRYPTO_ALGAPI select CRYPTO_AES_ARM64 config CRYPTO_AES_ARM64_CE_CCM tristate "AES in CCM mode using ARMv8 Crypto Extensions" - depends on ARM64 && KERNEL_MODE_NEON + depends on ARM64 && KERNEL_MODE_NEON && !PREEMPT_RT_BASE select CRYPTO_ALGAPI select CRYPTO_AES_ARM64_CE select CRYPTO_AES_ARM64 @ arch/arm64/crypto/Kconfig:88 @ config CRYPTO_AES_ARM64_CE_CCM config CRYPTO_AES_ARM64_CE_BLK tristate "AES in ECB/CBC/CTR/XTS modes using ARMv8 Crypto Extensions" - depends on KERNEL_MODE_NEON + depends on KERNEL_MODE_NEON && !PREEMPT_RT_BASE select CRYPTO_BLKCIPHER select CRYPTO_AES_ARM64_CE select CRYPTO_AES_ARM64 @ arch/arm64/crypto/Kconfig:96 @ config CRYPTO_AES_ARM64_CE_BLK config CRYPTO_AES_ARM64_NEON_BLK tristate "AES in ECB/CBC/CTR/XTS modes using NEON instructions" - depends on KERNEL_MODE_NEON + depends on KERNEL_MODE_NEON && !PREEMPT_RT_BASE select CRYPTO_BLKCIPHER select CRYPTO_AES_ARM64 select CRYPTO_AES @ arch/arm64/crypto/Kconfig:104 @ config CRYPTO_AES_ARM64_NEON_BLK config CRYPTO_CHACHA20_NEON tristate "NEON accelerated ChaCha20 symmetric cipher" - depends on KERNEL_MODE_NEON + depends on KERNEL_MODE_NEON && !PREEMPT_RT_BASE select CRYPTO_BLKCIPHER select CRYPTO_CHACHA20 config CRYPTO_AES_ARM64_BS tristate "AES in ECB/CBC/CTR/XTS modes using bit-sliced NEON algorithm" - depends on KERNEL_MODE_NEON + depends on KERNEL_MODE_NEON && !PREEMPT_RT_BASE select CRYPTO_BLKCIPHER select CRYPTO_AES_ARM64_NEON_BLK select CRYPTO_AES_ARM64 @ arch/arm64/crypto/crc32-ce-glue.c:211 @ static struct shash_alg crc32_pmull_algs[] = { { static int __init crc32_pmull_mod_init(void) { - if (IS_ENABLED(CONFIG_KERNEL_MODE_NEON) && (elf_hwcap & HWCAP_PMULL)) { + if (IS_ENABLED(CONFIG_KERNEL_MODE_NEON) && + !IS_ENABLED(CONFIG_PREEMPT_RT_BASE) && (elf_hwcap & HWCAP_PMULL)) { crc32_pmull_algs[0].update = crc32_pmull_update; crc32_pmull_algs[1].update = crc32c_pmull_update; @ arch/arm64/include/asm/spinlock_types.h:19 @ #ifndef __ASM_SPINLOCK_TYPES_H #define __ASM_SPINLOCK_TYPES_H -#if !defined(__LINUX_SPINLOCK_TYPES_H) && !defined(__ASM_SPINLOCK_H) -# error "please don't include this file directly" -#endif - #include <linux/types.h> #define TICKET_SHIFT 16 @ arch/arm64/include/asm/thread_info.h:46 @ struct thread_info { u64 ttbr0; /* saved TTBR0_EL1 */ #endif int preempt_count; /* 0 => preemptable, <0 => bug */ + int preempt_lazy_count; /* 0 => preemptable, <0 => bug */ }; #define INIT_THREAD_INFO(tsk) \ @ arch/arm64/include/asm/thread_info.h:86 @ void arch_release_task_struct(struct task_struct *tsk); #define TIF_FOREIGN_FPSTATE 3 /* CPU's FP state is not current's */ #define TIF_UPROBE 4 /* uprobe breakpoint or singlestep */ #define TIF_FSCHECK 5 /* Check FS is USER_DS on return */ +#define TIF_NEED_RESCHED_LAZY 6 #define TIF_NOHZ 7 #define TIF_SYSCALL_TRACE 8 #define TIF_SYSCALL_AUDIT 9 @ arch/arm64/include/asm/thread_info.h:104 @ void arch_release_task_struct(struct task_struct *tsk); #define _TIF_NEED_RESCHED (1 << TIF_NEED_RESCHED) #define _TIF_NOTIFY_RESUME (1 << TIF_NOTIFY_RESUME) #define _TIF_FOREIGN_FPSTATE (1 << TIF_FOREIGN_FPSTATE) +#define _TIF_NEED_RESCHED_LAZY (1 << TIF_NEED_RESCHED_LAZY) #define _TIF_NOHZ (1 << TIF_NOHZ) #define _TIF_SYSCALL_TRACE (1 << TIF_SYSCALL_TRACE) #define _TIF_SYSCALL_AUDIT (1 << TIF_SYSCALL_AUDIT) @ arch/arm64/include/asm/thread_info.h:117 @ void arch_release_task_struct(struct task_struct *tsk); #define _TIF_WORK_MASK (_TIF_NEED_RESCHED | _TIF_SIGPENDING | \ _TIF_NOTIFY_RESUME | _TIF_FOREIGN_FPSTATE | \ - _TIF_UPROBE | _TIF_FSCHECK) + _TIF_UPROBE | _TIF_FSCHECK | _TIF_NEED_RESCHED_LAZY) +#define _TIF_NEED_RESCHED_MASK (_TIF_NEED_RESCHED | _TIF_NEED_RESCHED_LAZY) #define _TIF_SYSCALL_WORK (_TIF_SYSCALL_TRACE | _TIF_SYSCALL_AUDIT | \ _TIF_SYSCALL_TRACEPOINT | _TIF_SECCOMP | \ _TIF_NOHZ) @ arch/arm64/kernel/asm-offsets.c:43 @ int main(void) BLANK(); DEFINE(TSK_TI_FLAGS, offsetof(struct task_struct, thread_info.flags)); DEFINE(TSK_TI_PREEMPT, offsetof(struct task_struct, thread_info.preempt_count)); + DEFINE(TSK_TI_PREEMPT_LAZY, offsetof(struct task_struct, thread_info.preempt_lazy_count)); DEFINE(TSK_TI_ADDR_LIMIT, offsetof(struct task_struct, thread_info.addr_limit)); #ifdef CONFIG_ARM64_SW_TTBR0_PAN DEFINE(TSK_TI_TTBR0, offsetof(struct task_struct, thread_info.ttbr0)); @ arch/arm64/kernel/entry.S:606 @ ENDPROC(el1_sync) #ifdef CONFIG_PREEMPT ldr w24, [tsk, #TSK_TI_PREEMPT] // get preempt count - cbnz w24, 1f // preempt count != 0 + cbnz w24, 2f // preempt count != 0 ldr x0, [tsk, #TSK_TI_FLAGS] // get flags - tbz x0, #TIF_NEED_RESCHED, 1f // needs rescheduling? - bl el1_preempt + tbnz x0, #TIF_NEED_RESCHED, 1f // needs rescheduling? + + ldr w24, [tsk, #TSK_TI_PREEMPT_LAZY] // get preempt lazy count + cbnz w24, 2f // preempt lazy count != 0 + tbz x0, #TIF_NEED_RESCHED_LAZY, 2f // needs rescheduling? 1: + bl el1_preempt +2: #endif #ifdef CONFIG_TRACE_IRQFLAGS bl trace_hardirqs_on @ arch/arm64/kernel/entry.S:629 @ ENDPROC(el1_irq) 1: bl preempt_schedule_irq // irq en/disable is done inside ldr x0, [tsk, #TSK_TI_FLAGS] // get new tasks TI_FLAGS tbnz x0, #TIF_NEED_RESCHED, 1b // needs rescheduling? + tbnz x0, #TIF_NEED_RESCHED_LAZY, 1b // needs rescheduling? ret x24 #endif @ arch/arm64/kernel/fpsimd.c:41 @ #include <linux/signal.h> #include <linux/slab.h> #include <linux/sysctl.h> +#include <linux/locallock.h> #include <asm/fpsimd.h> #include <asm/cputype.h> @ arch/arm64/kernel/fpsimd.c:239 @ static void sve_user_enable(void) * whether TIF_SVE is clear or set, since these are not vector length * dependent. */ - +static DEFINE_LOCAL_IRQ_LOCK(fpsimd_lock); /* * Update current's FPSIMD/SVE registers from thread_struct. * @ arch/arm64/kernel/fpsimd.c:598 @ int sve_set_vector_length(struct task_struct *task, * non-SVE thread. */ if (task == current) { + local_lock(fpsimd_lock); local_bh_disable(); task_fpsimd_save(); @ arch/arm64/kernel/fpsimd.c:609 @ int sve_set_vector_length(struct task_struct *task, if (test_and_clear_tsk_thread_flag(task, TIF_SVE)) sve_to_fpsimd(task); - if (task == current) + if (task == current) { + local_unlock(fpsimd_lock); local_bh_enable(); + } /* * Force reallocation of task SVE state to the correct size @ arch/arm64/kernel/fpsimd.c:845 @ asmlinkage void do_sve_acc(unsigned int esr, struct pt_regs *regs) sve_alloc(current); local_bh_disable(); + local_lock(fpsimd_lock); task_fpsimd_save(); fpsimd_to_sve(current); @ arch/arm64/kernel/fpsimd.c:857 @ asmlinkage void do_sve_acc(unsigned int esr, struct pt_regs *regs) if (test_and_set_thread_flag(TIF_SVE)) WARN_ON(1); /* SVE access shouldn't have trapped */ + local_unlock(fpsimd_lock); local_bh_enable(); } @ arch/arm64/kernel/fpsimd.c:935 @ void fpsimd_flush_thread(void) return; local_bh_disable(); + local_lock(fpsimd_lock); memset(¤t->thread.fpsimd_state, 0, sizeof(struct fpsimd_state)); fpsimd_flush_task_state(current); @ arch/arm64/kernel/fpsimd.c:977 @ void fpsimd_flush_thread(void) set_thread_flag(TIF_FOREIGN_FPSTATE); + local_unlock(fpsimd_lock); local_bh_enable(); } @ arch/arm64/kernel/fpsimd.c:991 @ void fpsimd_preserve_current_state(void) return; local_bh_disable(); + local_lock(fpsimd_lock); task_fpsimd_save(); + local_unlock(fpsimd_lock); local_bh_enable(); } @ arch/arm64/kernel/fpsimd.c:1035 @ void fpsimd_restore_current_state(void) return; local_bh_disable(); + local_lock(fpsimd_lock); if (test_and_clear_thread_flag(TIF_FOREIGN_FPSTATE)) { task_fpsimd_load(); fpsimd_bind_to_cpu(); } + local_unlock(fpsimd_lock); local_bh_enable(); } @ arch/arm64/kernel/fpsimd.c:1057 @ void fpsimd_update_current_state(struct user_fpsimd_state const *state) return; local_bh_disable(); + local_lock(fpsimd_lock); current->thread.fpsimd_state.user_fpsimd = *state; if (system_supports_sve() && test_thread_flag(TIF_SVE)) @ arch/arm64/kernel/fpsimd.c:1068 @ void fpsimd_update_current_state(struct user_fpsimd_state const *state) if (test_and_clear_thread_flag(TIF_FOREIGN_FPSTATE)) fpsimd_bind_to_cpu(); + local_unlock(fpsimd_lock); local_bh_enable(); } @ arch/arm64/kernel/fpsimd.c:1133 @ void kernel_neon_begin(void) BUG_ON(!may_use_simd()); local_bh_disable(); + local_lock(fpsimd_lock); __this_cpu_write(kernel_neon_busy, true); @ arch/arm64/kernel/fpsimd.c:1146 @ void kernel_neon_begin(void) /* Invalidate any task state remaining in the fpsimd regs: */ fpsimd_flush_cpu_state(); + local_unlock(fpsimd_lock); preempt_disable(); local_bh_enable(); @ arch/arm64/kernel/signal.c:915 @ asmlinkage void do_notify_resume(struct pt_regs *regs, /* Check valid user FS if needed */ addr_limit_user_check(); - if (thread_flags & _TIF_NEED_RESCHED) { + if (thread_flags & _TIF_NEED_RESCHED_MASK) { /* Unmask Debug and SError for the next task */ local_daif_restore(DAIF_PROCCTX_NOIRQ); @ arch/blackfin/include/asm/spinlock_types.h:10 @ #ifndef __ASM_SPINLOCK_TYPES_H #define __ASM_SPINLOCK_TYPES_H -#ifndef __LINUX_SPINLOCK_TYPES_H -# error "please don't include this file directly" -#endif - #include <asm/rwlock.h> typedef struct { @ arch/hexagon/include/asm/spinlock_types.h:24 @ #ifndef _ASM_SPINLOCK_TYPES_H #define _ASM_SPINLOCK_TYPES_H -#ifndef __LINUX_SPINLOCK_TYPES_H -# error "please don't include this file directly" -#endif - typedef struct { volatile unsigned int lock; } arch_spinlock_t; @ arch/ia64/include/asm/spinlock_types.h:5 @ #ifndef _ASM_IA64_SPINLOCK_TYPES_H #define _ASM_IA64_SPINLOCK_TYPES_H -#ifndef __LINUX_SPINLOCK_TYPES_H -# error "please don't include this file directly" -#endif - typedef struct { volatile unsigned int lock; } arch_spinlock_t; @ arch/ia64/kernel/mca.c:1827 @ format_mca_init_stack(void *mca_data, unsigned long offset, ti->cpu = cpu; p->stack = ti; p->state = TASK_UNINTERRUPTIBLE; - cpumask_set_cpu(cpu, &p->cpus_allowed); + cpumask_set_cpu(cpu, &p->cpus_mask); INIT_LIST_HEAD(&p->tasks); p->parent = p->real_parent = p->group_leader = p; INIT_LIST_HEAD(&p->children); @ arch/m32r/include/asm/spinlock_types.h:5 @ #ifndef _ASM_M32R_SPINLOCK_TYPES_H #define _ASM_M32R_SPINLOCK_TYPES_H -#ifndef __LINUX_SPINLOCK_TYPES_H -# error "please don't include this file directly" -#endif - typedef struct { volatile int slock; } arch_spinlock_t; @ arch/metag/include/asm/spinlock_types.h:5 @ #ifndef _ASM_METAG_SPINLOCK_TYPES_H #define _ASM_METAG_SPINLOCK_TYPES_H -#ifndef __LINUX_SPINLOCK_TYPES_H -# error "please don't include this file directly" -#endif - typedef struct { volatile unsigned int lock; } arch_spinlock_t; @ arch/mips/Kconfig:2519 @ config MIPS_ASID_BITS_VARIABLE # config HIGHMEM bool "High Memory Support" - depends on 32BIT && CPU_SUPPORTS_HIGHMEM && SYS_SUPPORTS_HIGHMEM && !CPU_MIPS32_3_5_EVA + depends on 32BIT && CPU_SUPPORTS_HIGHMEM && SYS_SUPPORTS_HIGHMEM && !CPU_MIPS32_3_5_EVA && !PREEMPT_RT_FULL config CPU_SUPPORTS_HIGHMEM bool @ arch/mips/include/asm/switch_to.h:45 @ extern struct task_struct *ll_task; * inline to try to keep the overhead down. If we have been forced to run on * a "CPU" with an FPU because of a previous high level of FP computation, * but did not actually use the FPU during the most recent time-slice (CU1 - * isn't set), we undo the restriction on cpus_allowed. + * isn't set), we undo the restriction on cpus_mask. * * We're not calling set_cpus_allowed() here, because we have no need to * force prompt migration - we're already switching the current CPU to a @ arch/mips/include/asm/switch_to.h:60 @ do { \ test_ti_thread_flag(__prev_ti, TIF_FPUBOUND) && \ (!(KSTK_STATUS(prev) & ST0_CU1))) { \ clear_ti_thread_flag(__prev_ti, TIF_FPUBOUND); \ - prev->cpus_allowed = prev->thread.user_cpus_allowed; \ + prev->cpus_mask = prev->thread.user_cpus_allowed; \ } \ next->thread.emulated_fp = 0; \ } while(0) @ arch/mips/kernel/mips-mt-fpaff.c:180 @ asmlinkage long mipsmt_sys_sched_getaffinity(pid_t pid, unsigned int len, if (retval) goto out_unlock; - cpumask_or(&allowed, &p->thread.user_cpus_allowed, &p->cpus_allowed); + cpumask_or(&allowed, &p->thread.user_cpus_allowed, p->cpus_ptr); cpumask_and(&mask, &allowed, cpu_active_mask); out_unlock: @ arch/mips/kernel/traps.c:1202 @ static void mt_ase_fp_affinity(void) * restricted the allowed set to exclude any CPUs with FPUs, * we'll skip the procedure. */ - if (cpumask_intersects(¤t->cpus_allowed, &mt_fpu_cpumask)) { + if (cpumask_intersects(¤t->cpus_mask, &mt_fpu_cpumask)) { cpumask_t tmask; current->thread.user_cpus_allowed - = current->cpus_allowed; - cpumask_and(&tmask, ¤t->cpus_allowed, + = current->cpus_mask; + cpumask_and(&tmask, ¤t->cpus_mask, &mt_fpu_cpumask); set_cpus_allowed_ptr(current, &tmask); set_thread_flag(TIF_FPUBOUND); @ arch/mn10300/include/asm/spinlock_types.h:5 @ #ifndef _ASM_SPINLOCK_TYPES_H #define _ASM_SPINLOCK_TYPES_H -#ifndef __LINUX_SPINLOCK_TYPES_H -# error "please don't include this file directly" -#endif - typedef struct arch_spinlock { unsigned int slock; } arch_spinlock_t; @ arch/powerpc/Kconfig:114 @ config LOCKDEP_SUPPORT config RWSEM_GENERIC_SPINLOCK bool + default y if PREEMPT_RT_FULL config RWSEM_XCHGADD_ALGORITHM bool - default y + default y if !PREEMPT_RT_FULL config GENERIC_LOCKBREAK bool @ arch/powerpc/Kconfig:222 @ config PPC select HAVE_HARDLOCKUP_DETECTOR_PERF if PERF_EVENTS && HAVE_PERF_EVENTS_NMI && !HAVE_HARDLOCKUP_DETECTOR_ARCH select HAVE_PERF_REGS select HAVE_PERF_USER_STACK_DUMP + select HAVE_PREEMPT_LAZY select HAVE_RCU_TABLE_FREE if SMP select HAVE_REGS_AND_STACK_ACCESS_API select HAVE_SYSCALL_TRACEPOINTS @ arch/powerpc/Kconfig:398 @ menu "Kernel options" config HIGHMEM bool "High memory support" - depends on PPC32 + depends on PPC32 && !PREEMPT_RT_FULL source kernel/Kconfig.hz source kernel/Kconfig.preempt @ arch/powerpc/include/asm/spinlock_types.h:5 @ #ifndef _ASM_POWERPC_SPINLOCK_TYPES_H #define _ASM_POWERPC_SPINLOCK_TYPES_H -#ifndef __LINUX_SPINLOCK_TYPES_H -# error "please don't include this file directly" -#endif - typedef struct { volatile unsigned int slock; } arch_spinlock_t; @ arch/powerpc/include/asm/thread_info.h:39 @ struct thread_info { int cpu; /* cpu we're on */ int preempt_count; /* 0 => preemptable, <0 => BUG */ + int preempt_lazy_count; /* 0 => preemptable, + <0 => BUG */ unsigned long local_flags; /* private flags for thread */ #ifdef CONFIG_LIVEPATCH unsigned long *livepatch_sp; @ arch/powerpc/include/asm/thread_info.h:83 @ static inline struct thread_info *current_thread_info(void) #define TIF_SYSCALL_TRACE 0 /* syscall trace active */ #define TIF_SIGPENDING 1 /* signal pending */ #define TIF_NEED_RESCHED 2 /* rescheduling necessary */ -#define TIF_POLLING_NRFLAG 3 /* true if poll_idle() is polling - TIF_NEED_RESCHED */ +#define TIF_NEED_RESCHED_LAZY 3 /* lazy rescheduling necessary */ #define TIF_32BIT 4 /* 32 bit binary */ #define TIF_RESTORE_TM 5 /* need to restore TM FP/VEC/VSX */ #define TIF_PATCH_PENDING 6 /* pending live patching update */ @ arch/powerpc/include/asm/thread_info.h:102 @ static inline struct thread_info *current_thread_info(void) #if defined(CONFIG_PPC64) #define TIF_ELF2ABI 18 /* function descriptors must die! */ #endif +#define TIF_POLLING_NRFLAG 19 /* true if poll_idle() is polling + TIF_NEED_RESCHED */ /* as above, but as bit values */ #define _TIF_SYSCALL_TRACE (1<<TIF_SYSCALL_TRACE) @ arch/powerpc/include/asm/thread_info.h:123 @ static inline struct thread_info *current_thread_info(void) #define _TIF_SYSCALL_TRACEPOINT (1<<TIF_SYSCALL_TRACEPOINT) #define _TIF_EMULATE_STACK_STORE (1<<TIF_EMULATE_STACK_STORE) #define _TIF_NOHZ (1<<TIF_NOHZ) +#define _TIF_NEED_RESCHED_LAZY (1<<TIF_NEED_RESCHED_LAZY) #define _TIF_SYSCALL_DOTRACE (_TIF_SYSCALL_TRACE | _TIF_SYSCALL_AUDIT | \ _TIF_SECCOMP | _TIF_SYSCALL_TRACEPOINT | \ _TIF_NOHZ) #define _TIF_USER_WORK_MASK (_TIF_SIGPENDING | _TIF_NEED_RESCHED | \ _TIF_NOTIFY_RESUME | _TIF_UPROBE | \ - _TIF_RESTORE_TM | _TIF_PATCH_PENDING) + _TIF_RESTORE_TM | _TIF_PATCH_PENDING | _TIF_NEED_RESCHED_LAZY) #define _TIF_PERSYSCALL_MASK (_TIF_RESTOREALL|_TIF_NOERROR) +#define _TIF_NEED_RESCHED_MASK (_TIF_NEED_RESCHED | _TIF_NEED_RESCHED_LAZY) /* Bits in local_flags */ /* Don't move TLF_NAPPING without adjusting the code in entry_32.S */ @ arch/powerpc/kernel/asm-offsets.c:159 @ int main(void) OFFSET(TI_FLAGS, thread_info, flags); OFFSET(TI_LOCAL_FLAGS, thread_info, local_flags); OFFSET(TI_PREEMPT, thread_info, preempt_count); + OFFSET(TI_PREEMPT_LAZY, thread_info, preempt_lazy_count); OFFSET(TI_TASK, thread_info, task); OFFSET(TI_CPU, thread_info, cpu); @ arch/powerpc/kernel/entry_32.S:869 @ user_exc_return: /* r10 contains MSR_KERNEL here */ cmpwi 0,r0,0 /* if non-zero, just restore regs and return */ bne restore andi. r8,r8,_TIF_NEED_RESCHED + bne+ 1f + lwz r0,TI_PREEMPT_LAZY(r9) + cmpwi 0,r0,0 /* if non-zero, just restore regs and return */ + bne restore + lwz r0,TI_FLAGS(r9) + andi. r0,r0,_TIF_NEED_RESCHED_LAZY beq+ restore +1: lwz r3,_MSR(r1) andi. r0,r3,MSR_EE /* interrupts off? */ beq restore /* don't schedule if so */ @ arch/powerpc/kernel/entry_32.S:887 @ user_exc_return: /* r10 contains MSR_KERNEL here */ */ bl trace_hardirqs_off #endif -1: bl preempt_schedule_irq +2: bl preempt_schedule_irq CURRENT_THREAD_INFO(r9, r1) lwz r3,TI_FLAGS(r9) - andi. r0,r3,_TIF_NEED_RESCHED - bne- 1b + andi. r0,r3,_TIF_NEED_RESCHED_MASK + bne- 2b #ifdef CONFIG_TRACE_IRQFLAGS /* And now, to properly rebalance the above, we tell lockdep they * are being turned back on, which will happen when we return @ arch/powerpc/kernel/entry_32.S:1214 @ END_FTR_SECTION_IFSET(CPU_FTR_NEED_PAIRED_STWCX) #endif /* !(CONFIG_4xx || CONFIG_BOOKE) */ do_work: /* r10 contains MSR_KERNEL here */ - andi. r0,r9,_TIF_NEED_RESCHED + andi. r0,r9,_TIF_NEED_RESCHED_MASK beq do_user_signal do_resched: /* r10 contains MSR_KERNEL here */ @ arch/powerpc/kernel/entry_32.S:1235 @ do_resched: /* r10 contains MSR_KERNEL here */ MTMSRD(r10) /* disable interrupts */ CURRENT_THREAD_INFO(r9, r1) lwz r9,TI_FLAGS(r9) - andi. r0,r9,_TIF_NEED_RESCHED + andi. r0,r9,_TIF_NEED_RESCHED_MASK bne- do_resched andi. r0,r9,_TIF_USER_WORK_MASK beq restore_user @ arch/powerpc/kernel/entry_64.S:691 @ _GLOBAL(ret_from_except_lite) bl restore_math b restore #endif -1: andi. r0,r4,_TIF_NEED_RESCHED +1: andi. r0,r4,_TIF_NEED_RESCHED_MASK beq 2f bl restore_interrupts SCHEDULE_USER @ arch/powerpc/kernel/entry_64.S:753 @ _GLOBAL(ret_from_except_lite) #ifdef CONFIG_PREEMPT /* Check if we need to preempt */ - andi. r0,r4,_TIF_NEED_RESCHED - beq+ restore - /* Check that preempt_count() == 0 and interrupts are enabled */ lwz r8,TI_PREEMPT(r9) + cmpwi 0,r8,0 /* if non-zero, just restore regs and return */ + bne restore + andi. r0,r4,_TIF_NEED_RESCHED + bne+ check_count + + andi. r0,r4,_TIF_NEED_RESCHED_LAZY + beq+ restore + lwz r8,TI_PREEMPT_LAZY(r9) + + /* Check that preempt_count() == 0 and interrupts are enabled */ +check_count: cmpwi cr0,r8,0 bne restore ld r0,SOFTE(r1) @ arch/powerpc/kernel/entry_64.S:781 @ _GLOBAL(ret_from_except_lite) /* Re-test flags and eventually loop */ CURRENT_THREAD_INFO(r9, r1) ld r4,TI_FLAGS(r9) - andi. r0,r4,_TIF_NEED_RESCHED + andi. r0,r4,_TIF_NEED_RESCHED_MASK bne 1b /* @ arch/powerpc/kernel/irq.c:742 @ void irq_ctx_init(void) } } +#ifndef CONFIG_PREEMPT_RT_FULL void do_softirq_own_stack(void) { struct thread_info *curtp, *irqtp; @ arch/powerpc/kernel/irq.c:760 @ void do_softirq_own_stack(void) if (irqtp->flags) set_bits(irqtp->flags, &curtp->flags); } +#endif irq_hw_number_t virq_to_hw(unsigned int virq) { @ arch/powerpc/kernel/misc_32.S:44 @ * We store the saved ksp_limit in the unused part * of the STACK_FRAME_OVERHEAD */ +#ifndef CONFIG_PREEMPT_RT_FULL _GLOBAL(call_do_softirq) mflr r0 stw r0,4(r1) @ arch/powerpc/kernel/misc_32.S:61 @ _GLOBAL(call_do_softirq) stw r10,THREAD+KSP_LIMIT(r2) mtlr r0 blr +#endif /* * void call_do_irq(struct pt_regs *regs, struct thread_info *irqtp); @ arch/powerpc/kernel/misc_64.S:34 @ .text +#ifndef CONFIG_PREEMPT_RT_FULL _GLOBAL(call_do_softirq) mflr r0 std r0,16(r1) @ arch/powerpc/kernel/misc_64.S:45 @ _GLOBAL(call_do_softirq) ld r0,16(r1) mtlr r0 blr +#endif _GLOBAL(call_do_irq) mflr r0 @ arch/powerpc/kvm/Kconfig:181 @ config KVM_E500MC config KVM_MPIC bool "KVM in-kernel MPIC emulation" depends on KVM && E500 + depends on !PREEMPT_RT_FULL select HAVE_KVM_IRQCHIP select HAVE_KVM_IRQFD select HAVE_KVM_IRQ_ROUTING @ arch/powerpc/platforms/cell/spufs/sched.c:144 @ void __spu_update_sched_info(struct spu_context *ctx) * runqueue. The context will be rescheduled on the proper node * if it is timesliced or preempted. */ - cpumask_copy(&ctx->cpus_allowed, ¤t->cpus_allowed); + cpumask_copy(&ctx->cpus_allowed, current->cpus_ptr); /* Save the current cpu id for spu interrupt routing. */ ctx->last_ran = raw_smp_processor_id(); @ arch/powerpc/platforms/ps3/device-init.c:755 @ static int ps3_notification_read_write(struct ps3_notification_device *dev, } pr_debug("%s:%u: notification %s issued\n", __func__, __LINE__, op); - res = wait_event_interruptible(dev->done.wait, + res = swait_event_interruptible(dev->done.wait, dev->done.done || kthread_should_stop()); if (kthread_should_stop()) res = -EINTR; @ arch/s390/include/asm/spinlock_types.h:5 @ #ifndef __ASM_SPINLOCK_TYPES_H #define __ASM_SPINLOCK_TYPES_H -#ifndef __LINUX_SPINLOCK_TYPES_H -# error "please don't include this file directly" -#endif - typedef struct { int lock; } __attribute__ ((aligned (4))) arch_spinlock_t; @ arch/sh/include/asm/spinlock_types.h:5 @ #ifndef __ASM_SH_SPINLOCK_TYPES_H #define __ASM_SH_SPINLOCK_TYPES_H -#ifndef __LINUX_SPINLOCK_TYPES_H -# error "please don't include this file directly" -#endif - typedef struct { volatile unsigned int lock; } arch_spinlock_t; @ arch/sh/kernel/irq.c:151 @ void irq_ctx_exit(int cpu) hardirq_ctx[cpu] = NULL; } +#ifndef CONFIG_PREEMPT_RT_FULL void do_softirq_own_stack(void) { struct thread_info *curctx; @ arch/sh/kernel/irq.c:179 @ void do_softirq_own_stack(void) "r5", "r6", "r7", "r8", "r9", "r15", "t", "pr" ); } +#endif #else static inline void handle_one_irq(unsigned int irq) { @ arch/sparc/kernel/irq_64.c:858 @ void __irq_entry handler_irq(int pil, struct pt_regs *regs) set_irq_regs(old_regs); } +#ifndef CONFIG_PREEMPT_RT_FULL void do_softirq_own_stack(void) { void *orig_sp, *sp = softirq_stack[smp_processor_id()]; @ arch/sparc/kernel/irq_64.c:873 @ void do_softirq_own_stack(void) __asm__ __volatile__("mov %0, %%sp" : : "r" (orig_sp)); } +#endif #ifdef CONFIG_HOTPLUG_CPU void fixup_irqs(void) @ arch/tile/include/asm/setup.h:52 @ int hardwall_ipi_valid(int cpu); /* Hook hardwall code into changes in affinity. */ #define arch_set_cpus_allowed(p, new_mask) do { \ - if (!cpumask_equal(&p->cpus_allowed, new_mask)) \ + if (!cpumask_equal(p->cpus_ptr, new_mask)) \ hardwall_deactivate_all(p); \ } while (0) #endif @ arch/tile/include/asm/spinlock_types.h:18 @ #ifndef _ASM_TILE_SPINLOCK_TYPES_H #define _ASM_TILE_SPINLOCK_TYPES_H -#ifndef __LINUX_SPINLOCK_TYPES_H -# error "please don't include this file directly" -#endif - #ifdef __tilegx__ /* Low 15 bits are "next"; high 15 bits are "current". */ @ arch/tile/kernel/hardwall.c:593 @ static int hardwall_activate(struct hardwall_info *info) * Get our affinity; if we're not bound to this tile uniquely, * we can't access the network registers. */ - if (cpumask_weight(&p->cpus_allowed) != 1) + if (p->nr_cpus_allowed != 1) return -EPERM; /* Make sure we are bound to a cpu assigned to this resource. */ cpu = smp_processor_id(); - BUG_ON(cpumask_first(&p->cpus_allowed) != cpu); + BUG_ON(cpumask_first(p->cpus_ptr) != cpu); if (!cpumask_test_cpu(cpu, &info->cpumask)) return -EINVAL; @ arch/tile/kernel/hardwall.c:624 @ static int hardwall_activate(struct hardwall_info *info) * Deactivate a task's hardwall. Must hold lock for hardwall_type. * This method may be called from exit_thread(), so we don't want to * rely on too many fields of struct task_struct still being valid. - * We assume the cpus_allowed, pid, and comm fields are still valid. + * We assume the nr_cpus_allowed, pid, and comm fields are still valid. */ static void _hardwall_deactivate(struct hardwall_type *hwt, struct task_struct *task) { struct thread_struct *ts = &task->thread; - if (cpumask_weight(&task->cpus_allowed) != 1) { + if (task->nr_cpus_allowed != 1) { pr_err("pid %d (%s) releasing %s hardwall with an affinity mask containing %d cpus!\n", task->pid, task->comm, hwt->name, - cpumask_weight(&task->cpus_allowed)); + task->nr_cpus_allowed); BUG(); } @ arch/x86/Kconfig:177 @ config X86 select HAVE_HARDLOCKUP_DETECTOR_PERF if PERF_EVENTS && HAVE_PERF_EVENTS_NMI select HAVE_PERF_REGS select HAVE_PERF_USER_STACK_DUMP + select HAVE_PREEMPT_LAZY select HAVE_RCU_TABLE_FREE select HAVE_REGS_AND_STACK_ACCESS_API select HAVE_RELIABLE_STACKTRACE if X86_64 && UNWINDER_FRAME_POINTER && STACK_VALIDATION @ arch/x86/Kconfig:264 @ config ARCH_MAY_HAVE_PC_FDC def_bool y depends on ISA_DMA_API +config RWSEM_GENERIC_SPINLOCK + def_bool PREEMPT_RT_FULL + config RWSEM_XCHGADD_ALGORITHM - def_bool y + def_bool !RWSEM_GENERIC_SPINLOCK && !PREEMPT_RT_FULL config GENERIC_CALIBRATE_DELAY def_bool y @ arch/x86/Kconfig:952 @ config IOMMU_HELPER config MAXSMP bool "Enable Maximum number of SMP Processors and NUMA Nodes" depends on X86_64 && SMP && DEBUG_KERNEL - select CPUMASK_OFFSTACK + select CPUMASK_OFFSTACK if !PREEMPT_RT_FULL ---help--- Enable maximum number of CPUS and NUMA Nodes for this architecture. If unsure, say N. @ arch/x86/crypto/aesni-intel_glue.c:390 @ static int ecb_encrypt(struct skcipher_request *req) err = skcipher_walk_virt(&walk, req, true); - kernel_fpu_begin(); while ((nbytes = walk.nbytes)) { + kernel_fpu_begin(); aesni_ecb_enc(ctx, walk.dst.virt.addr, walk.src.virt.addr, nbytes & AES_BLOCK_MASK); + kernel_fpu_end(); nbytes &= AES_BLOCK_SIZE - 1; err = skcipher_walk_done(&walk, nbytes); } - kernel_fpu_end(); return err; } @ arch/x86/crypto/aesni-intel_glue.c:412 @ static int ecb_decrypt(struct skcipher_request *req) err = skcipher_walk_virt(&walk, req, true); - kernel_fpu_begin(); while ((nbytes = walk.nbytes)) { + kernel_fpu_begin(); aesni_ecb_dec(ctx, walk.dst.virt.addr, walk.src.virt.addr, nbytes & AES_BLOCK_MASK); + kernel_fpu_end(); nbytes &= AES_BLOCK_SIZE - 1; err = skcipher_walk_done(&walk, nbytes); } - kernel_fpu_end(); return err; } @ arch/x86/crypto/aesni-intel_glue.c:434 @ static int cbc_encrypt(struct skcipher_request *req) err = skcipher_walk_virt(&walk, req, true); - kernel_fpu_begin(); while ((nbytes = walk.nbytes)) { + kernel_fpu_begin(); aesni_cbc_enc(ctx, walk.dst.virt.addr, walk.src.virt.addr, nbytes & AES_BLOCK_MASK, walk.iv); + kernel_fpu_end(); nbytes &= AES_BLOCK_SIZE - 1; err = skcipher_walk_done(&walk, nbytes); } - kernel_fpu_end(); return err; } @ arch/x86/crypto/aesni-intel_glue.c:456 @ static int cbc_decrypt(struct skcipher_request *req) err = skcipher_walk_virt(&walk, req, true); - kernel_fpu_begin(); while ((nbytes = walk.nbytes)) { + kernel_fpu_begin(); aesni_cbc_dec(ctx, walk.dst.virt.addr, walk.src.virt.addr, nbytes & AES_BLOCK_MASK, walk.iv); + kernel_fpu_end(); nbytes &= AES_BLOCK_SIZE - 1; err = skcipher_walk_done(&walk, nbytes); } - kernel_fpu_end(); return err; } @ arch/x86/crypto/aesni-intel_glue.c:513 @ static int ctr_crypt(struct skcipher_request *req) err = skcipher_walk_virt(&walk, req, true); - kernel_fpu_begin(); while ((nbytes = walk.nbytes) >= AES_BLOCK_SIZE) { + kernel_fpu_begin(); aesni_ctr_enc_tfm(ctx, walk.dst.virt.addr, walk.src.virt.addr, nbytes & AES_BLOCK_MASK, walk.iv); + kernel_fpu_end(); nbytes &= AES_BLOCK_SIZE - 1; err = skcipher_walk_done(&walk, nbytes); } if (walk.nbytes) { + kernel_fpu_begin(); ctr_crypt_final(ctx, &walk); + kernel_fpu_end(); err = skcipher_walk_done(&walk, 0); } - kernel_fpu_end(); return err; } @ arch/x86/crypto/camellia_aesni_avx2_glue.c:209 @ struct crypt_priv { bool fpu_enabled; }; +#ifdef CONFIG_PREEMPT_RT_FULL +static void camellia_fpu_end_rt(struct crypt_priv *ctx) +{ + bool fpu_enabled = ctx->fpu_enabled; + + if (!fpu_enabled) + return; + camellia_fpu_end(fpu_enabled); + ctx->fpu_enabled = false; +} +#else +static void camellia_fpu_end_rt(struct crypt_priv *ctx) { } +#endif + static void encrypt_callback(void *priv, u8 *srcdst, unsigned int nbytes) { const unsigned int bsize = CAMELLIA_BLOCK_SIZE; @ arch/x86/crypto/camellia_aesni_avx2_glue.c:238 @ static void encrypt_callback(void *priv, u8 *srcdst, unsigned int nbytes) } if (nbytes >= CAMELLIA_AESNI_PARALLEL_BLOCKS * bsize) { + kernel_fpu_resched(); camellia_ecb_enc_16way(ctx->ctx, srcdst, srcdst); srcdst += bsize * CAMELLIA_AESNI_PARALLEL_BLOCKS; nbytes -= bsize * CAMELLIA_AESNI_PARALLEL_BLOCKS; } while (nbytes >= CAMELLIA_PARALLEL_BLOCKS * bsize) { + kernel_fpu_resched(); camellia_enc_blk_2way(ctx->ctx, srcdst, srcdst); srcdst += bsize * CAMELLIA_PARALLEL_BLOCKS; nbytes -= bsize * CAMELLIA_PARALLEL_BLOCKS; } + camellia_fpu_end_rt(ctx); for (i = 0; i < nbytes / bsize; i++, srcdst += bsize) camellia_enc_blk(ctx->ctx, srcdst, srcdst); @ arch/x86/crypto/camellia_aesni_avx2_glue.c:271 @ static void decrypt_callback(void *priv, u8 *srcdst, unsigned int nbytes) } if (nbytes >= CAMELLIA_AESNI_PARALLEL_BLOCKS * bsize) { + kernel_fpu_resched(); camellia_ecb_dec_16way(ctx->ctx, srcdst, srcdst); srcdst += bsize * CAMELLIA_AESNI_PARALLEL_BLOCKS; nbytes -= bsize * CAMELLIA_AESNI_PARALLEL_BLOCKS; } while (nbytes >= CAMELLIA_PARALLEL_BLOCKS * bsize) { + kernel_fpu_resched(); camellia_dec_blk_2way(ctx->ctx, srcdst, srcdst); srcdst += bsize * CAMELLIA_PARALLEL_BLOCKS; nbytes -= bsize * CAMELLIA_PARALLEL_BLOCKS; } + camellia_fpu_end_rt(ctx); for (i = 0; i < nbytes / bsize; i++, srcdst += bsize) camellia_dec_blk(ctx->ctx, srcdst, srcdst); @ arch/x86/crypto/camellia_aesni_avx_glue.c:213 @ struct crypt_priv { bool fpu_enabled; }; +#ifdef CONFIG_PREEMPT_RT_FULL +static void camellia_fpu_end_rt(struct crypt_priv *ctx) +{ + bool fpu_enabled = ctx->fpu_enabled; + + if (!fpu_enabled) + return; + camellia_fpu_end(fpu_enabled); + ctx->fpu_enabled = false; +} + +#else +static void camellia_fpu_end_rt(struct crypt_priv *ctx) { } +#endif + static void encrypt_callback(void *priv, u8 *srcdst, unsigned int nbytes) { const unsigned int bsize = CAMELLIA_BLOCK_SIZE; @ arch/x86/crypto/camellia_aesni_avx_glue.c:243 @ static void encrypt_callback(void *priv, u8 *srcdst, unsigned int nbytes) } while (nbytes >= CAMELLIA_PARALLEL_BLOCKS * bsize) { + kernel_fpu_resched(); camellia_enc_blk_2way(ctx->ctx, srcdst, srcdst); srcdst += bsize * CAMELLIA_PARALLEL_BLOCKS; nbytes -= bsize * CAMELLIA_PARALLEL_BLOCKS; } + camellia_fpu_end_rt(ctx); for (i = 0; i < nbytes / bsize; i++, srcdst += bsize) camellia_enc_blk(ctx->ctx, srcdst, srcdst); @ arch/x86/crypto/camellia_aesni_avx_glue.c:269 @ static void decrypt_callback(void *priv, u8 *srcdst, unsigned int nbytes) } while (nbytes >= CAMELLIA_PARALLEL_BLOCKS * bsize) { + kernel_fpu_resched(); camellia_dec_blk_2way(ctx->ctx, srcdst, srcdst); srcdst += bsize * CAMELLIA_PARALLEL_BLOCKS; nbytes -= bsize * CAMELLIA_PARALLEL_BLOCKS; } + camellia_fpu_end_rt(ctx); for (i = 0; i < nbytes / bsize; i++, srcdst += bsize) camellia_dec_blk(ctx->ctx, srcdst, srcdst); @ arch/x86/crypto/cast5_avx_glue.c:62 @ static inline void cast5_fpu_end(bool fpu_enabled) static int ecb_crypt(struct blkcipher_desc *desc, struct blkcipher_walk *walk, bool enc) { - bool fpu_enabled = false; + bool fpu_enabled; struct cast5_ctx *ctx = crypto_blkcipher_ctx(desc->tfm); const unsigned int bsize = CAST5_BLOCK_SIZE; unsigned int nbytes; @ arch/x86/crypto/cast5_avx_glue.c:76 @ static int ecb_crypt(struct blkcipher_desc *desc, struct blkcipher_walk *walk, u8 *wsrc = walk->src.virt.addr; u8 *wdst = walk->dst.virt.addr; - fpu_enabled = cast5_fpu_begin(fpu_enabled, nbytes); + fpu_enabled = cast5_fpu_begin(false, nbytes); /* Process multi-block batch */ if (nbytes >= bsize * CAST5_PARALLEL_BLOCKS) { @ arch/x86/crypto/cast5_avx_glue.c:105 @ static int ecb_crypt(struct blkcipher_desc *desc, struct blkcipher_walk *walk, } while (nbytes >= bsize); done: + cast5_fpu_end(fpu_enabled); err = blkcipher_walk_done(desc, walk, nbytes); } - - cast5_fpu_end(fpu_enabled); return err; } @ arch/x86/crypto/cast5_avx_glue.c:228 @ static unsigned int __cbc_decrypt(struct blkcipher_desc *desc, static int cbc_decrypt(struct blkcipher_desc *desc, struct scatterlist *dst, struct scatterlist *src, unsigned int nbytes) { - bool fpu_enabled = false; + bool fpu_enabled; struct blkcipher_walk walk; int err; @ arch/x86/crypto/cast5_avx_glue.c:237 @ static int cbc_decrypt(struct blkcipher_desc *desc, struct scatterlist *dst, desc->flags &= ~CRYPTO_TFM_REQ_MAY_SLEEP; while ((nbytes = walk.nbytes)) { - fpu_enabled = cast5_fpu_begin(fpu_enabled, nbytes); + fpu_enabled = cast5_fpu_begin(false, nbytes); nbytes = __cbc_decrypt(desc, &walk); + cast5_fpu_end(fpu_enabled); err = blkcipher_walk_done(desc, &walk, nbytes); } - - cast5_fpu_end(fpu_enabled); return err; } @ arch/x86/crypto/cast5_avx_glue.c:310 @ static unsigned int __ctr_crypt(struct blkcipher_desc *desc, static int ctr_crypt(struct blkcipher_desc *desc, struct scatterlist *dst, struct scatterlist *src, unsigned int nbytes) { - bool fpu_enabled = false; + bool fpu_enabled; struct blkcipher_walk walk; int err; @ arch/x86/crypto/cast5_avx_glue.c:319 @ static int ctr_crypt(struct blkcipher_desc *desc, struct scatterlist *dst, desc->flags &= ~CRYPTO_TFM_REQ_MAY_SLEEP; while ((nbytes = walk.nbytes) >= CAST5_BLOCK_SIZE) { - fpu_enabled = cast5_fpu_begin(fpu_enabled, nbytes); + fpu_enabled = cast5_fpu_begin(false, nbytes); nbytes = __ctr_crypt(desc, &walk); + cast5_fpu_end(fpu_enabled); err = blkcipher_walk_done(desc, &walk, nbytes); } - cast5_fpu_end(fpu_enabled); - if (walk.nbytes) { ctr_crypt_final(desc, &walk); err = blkcipher_walk_done(desc, &walk, 0); @ arch/x86/crypto/cast6_avx_glue.c:208 @ struct crypt_priv { bool fpu_enabled; }; +#ifdef CONFIG_PREEMPT_RT_FULL +static void cast6_fpu_end_rt(struct crypt_priv *ctx) +{ + bool fpu_enabled = ctx->fpu_enabled; + + if (!fpu_enabled) + return; + cast6_fpu_end(fpu_enabled); + ctx->fpu_enabled = false; +} + +#else +static void cast6_fpu_end_rt(struct crypt_priv *ctx) { } +#endif + static void encrypt_callback(void *priv, u8 *srcdst, unsigned int nbytes) { const unsigned int bsize = CAST6_BLOCK_SIZE; struct crypt_priv *ctx = priv; int i; - ctx->fpu_enabled = cast6_fpu_begin(ctx->fpu_enabled, nbytes); - if (nbytes == bsize * CAST6_PARALLEL_BLOCKS) { + ctx->fpu_enabled = cast6_fpu_begin(ctx->fpu_enabled, nbytes); cast6_ecb_enc_8way(ctx->ctx, srcdst, srcdst); + cast6_fpu_end_rt(ctx); return; } - for (i = 0; i < nbytes / bsize; i++, srcdst += bsize) __cast6_encrypt(ctx->ctx, srcdst, srcdst); } @ arch/x86/crypto/cast6_avx_glue.c:245 @ static void decrypt_callback(void *priv, u8 *srcdst, unsigned int nbytes) struct crypt_priv *ctx = priv; int i; - ctx->fpu_enabled = cast6_fpu_begin(ctx->fpu_enabled, nbytes); - if (nbytes == bsize * CAST6_PARALLEL_BLOCKS) { + ctx->fpu_enabled = cast6_fpu_begin(ctx->fpu_enabled, nbytes); cast6_ecb_dec_8way(ctx->ctx, srcdst, srcdst); + cast6_fpu_end_rt(ctx); return; } @ arch/x86/crypto/chacha20_glue.c:84 @ static int chacha20_simd(struct skcipher_request *req) crypto_chacha20_init(state, ctx, walk.iv); - kernel_fpu_begin(); - while (walk.nbytes >= CHACHA20_BLOCK_SIZE) { + kernel_fpu_begin(); + chacha20_dosimd(state, walk.dst.virt.addr, walk.src.virt.addr, rounddown(walk.nbytes, CHACHA20_BLOCK_SIZE)); + kernel_fpu_end(); err = skcipher_walk_done(&walk, walk.nbytes % CHACHA20_BLOCK_SIZE); } if (walk.nbytes) { + kernel_fpu_begin(); chacha20_dosimd(state, walk.dst.virt.addr, walk.src.virt.addr, walk.nbytes); + kernel_fpu_end(); err = skcipher_walk_done(&walk, 0); } - kernel_fpu_end(); - return err; } @ arch/x86/crypto/glue_helper.c:43 @ static int __glue_ecb_crypt_128bit(const struct common_glue_ctx *gctx, void *ctx = crypto_blkcipher_ctx(desc->tfm); const unsigned int bsize = 128 / 8; unsigned int nbytes, i, func_bytes; - bool fpu_enabled = false; + bool fpu_enabled; int err; err = blkcipher_walk_virt(desc, walk); @ arch/x86/crypto/glue_helper.c:53 @ static int __glue_ecb_crypt_128bit(const struct common_glue_ctx *gctx, u8 *wdst = walk->dst.virt.addr; fpu_enabled = glue_fpu_begin(bsize, gctx->fpu_blocks_limit, - desc, fpu_enabled, nbytes); + desc, false, nbytes); for (i = 0; i < gctx->num_funcs; i++) { func_bytes = bsize * gctx->funcs[i].num_blocks; @ arch/x86/crypto/glue_helper.c:75 @ static int __glue_ecb_crypt_128bit(const struct common_glue_ctx *gctx, } done: + glue_fpu_end(fpu_enabled); err = blkcipher_walk_done(desc, walk, nbytes); } - glue_fpu_end(fpu_enabled); return err; } @ arch/x86/crypto/glue_helper.c:195 @ int glue_cbc_decrypt_128bit(const struct common_glue_ctx *gctx, struct scatterlist *src, unsigned int nbytes) { const unsigned int bsize = 128 / 8; - bool fpu_enabled = false; + bool fpu_enabled; struct blkcipher_walk walk; int err; @ arch/x86/crypto/glue_helper.c:204 @ int glue_cbc_decrypt_128bit(const struct common_glue_ctx *gctx, while ((nbytes = walk.nbytes)) { fpu_enabled = glue_fpu_begin(bsize, gctx->fpu_blocks_limit, - desc, fpu_enabled, nbytes); + desc, false, nbytes); nbytes = __glue_cbc_decrypt_128bit(gctx, desc, &walk); + glue_fpu_end(fpu_enabled); err = blkcipher_walk_done(desc, &walk, nbytes); } - glue_fpu_end(fpu_enabled); return err; } EXPORT_SYMBOL_GPL(glue_cbc_decrypt_128bit); @ arch/x86/crypto/glue_helper.c:278 @ int glue_ctr_crypt_128bit(const struct common_glue_ctx *gctx, struct scatterlist *src, unsigned int nbytes) { const unsigned int bsize = 128 / 8; - bool fpu_enabled = false; + bool fpu_enabled; struct blkcipher_walk walk; int err; @ arch/x86/crypto/glue_helper.c:287 @ int glue_ctr_crypt_128bit(const struct common_glue_ctx *gctx, while ((nbytes = walk.nbytes) >= bsize) { fpu_enabled = glue_fpu_begin(bsize, gctx->fpu_blocks_limit, - desc, fpu_enabled, nbytes); + desc, false, nbytes); nbytes = __glue_ctr_crypt_128bit(gctx, desc, &walk); + glue_fpu_end(fpu_enabled); err = blkcipher_walk_done(desc, &walk, nbytes); } - glue_fpu_end(fpu_enabled); - if (walk.nbytes) { glue_ctr_crypt_final_128bit( gctx->funcs[gctx->num_funcs - 1].fn_u.ctr, desc, &walk); @ arch/x86/crypto/glue_helper.c:382 @ int glue_xts_crypt_128bit(const struct common_glue_ctx *gctx, void *tweak_ctx, void *crypt_ctx) { const unsigned int bsize = 128 / 8; - bool fpu_enabled = false; + bool fpu_enabled; struct blkcipher_walk walk; int err; @ arch/x86/crypto/glue_helper.c:395 @ int glue_xts_crypt_128bit(const struct common_glue_ctx *gctx, /* set minimum length to bsize, for tweak_fn */ fpu_enabled = glue_fpu_begin(bsize, gctx->fpu_blocks_limit, - desc, fpu_enabled, + desc, false, nbytes < bsize ? bsize : nbytes); - /* calculate first value of T */ tweak_fn(tweak_ctx, walk.iv, walk.iv); + glue_fpu_end(fpu_enabled); while (nbytes) { + fpu_enabled = glue_fpu_begin(bsize, gctx->fpu_blocks_limit, + desc, false, nbytes); nbytes = __glue_xts_crypt_128bit(gctx, crypt_ctx, desc, &walk); + glue_fpu_end(fpu_enabled); err = blkcipher_walk_done(desc, &walk, nbytes); nbytes = walk.nbytes; } - - glue_fpu_end(fpu_enabled); - return err; } EXPORT_SYMBOL_GPL(glue_xts_crypt_128bit); @ arch/x86/crypto/serpent_avx2_glue.c:187 @ struct crypt_priv { bool fpu_enabled; }; +#ifdef CONFIG_PREEMPT_RT_FULL +static void serpent_fpu_end_rt(struct crypt_priv *ctx) +{ + bool fpu_enabled = ctx->fpu_enabled; + + if (!fpu_enabled) + return; + serpent_fpu_end(fpu_enabled); + ctx->fpu_enabled = false; +} + +#else +static void serpent_fpu_end_rt(struct crypt_priv *ctx) { } +#endif + static void encrypt_callback(void *priv, u8 *srcdst, unsigned int nbytes) { const unsigned int bsize = SERPENT_BLOCK_SIZE; @ arch/x86/crypto/serpent_avx2_glue.c:217 @ static void encrypt_callback(void *priv, u8 *srcdst, unsigned int nbytes) } while (nbytes >= SERPENT_PARALLEL_BLOCKS * bsize) { + kernel_fpu_resched(); serpent_ecb_enc_8way_avx(ctx->ctx, srcdst, srcdst); srcdst += bsize * SERPENT_PARALLEL_BLOCKS; nbytes -= bsize * SERPENT_PARALLEL_BLOCKS; } + serpent_fpu_end_rt(ctx); for (i = 0; i < nbytes / bsize; i++, srcdst += bsize) __serpent_encrypt(ctx->ctx, srcdst, srcdst); @ arch/x86/crypto/serpent_avx2_glue.c:243 @ static void decrypt_callback(void *priv, u8 *srcdst, unsigned int nbytes) } while (nbytes >= SERPENT_PARALLEL_BLOCKS * bsize) { + kernel_fpu_resched(); serpent_ecb_dec_8way_avx(ctx->ctx, srcdst, srcdst); srcdst += bsize * SERPENT_PARALLEL_BLOCKS; nbytes -= bsize * SERPENT_PARALLEL_BLOCKS; } + serpent_fpu_end_rt(ctx); for (i = 0; i < nbytes / bsize; i++, srcdst += bsize) __serpent_decrypt(ctx->ctx, srcdst, srcdst); @ arch/x86/crypto/serpent_avx_glue.c:221 @ struct crypt_priv { bool fpu_enabled; }; +#ifdef CONFIG_PREEMPT_RT_FULL +static void serpent_fpu_end_rt(struct crypt_priv *ctx) +{ + bool fpu_enabled = ctx->fpu_enabled; + + if (!fpu_enabled) + return; + serpent_fpu_end(fpu_enabled); + ctx->fpu_enabled = false; +} + +#else +static void serpent_fpu_end_rt(struct crypt_priv *ctx) { } +#endif + static void encrypt_callback(void *priv, u8 *srcdst, unsigned int nbytes) { const unsigned int bsize = SERPENT_BLOCK_SIZE; struct crypt_priv *ctx = priv; int i; - ctx->fpu_enabled = serpent_fpu_begin(ctx->fpu_enabled, nbytes); - if (nbytes == bsize * SERPENT_PARALLEL_BLOCKS) { + ctx->fpu_enabled = serpent_fpu_begin(ctx->fpu_enabled, nbytes); serpent_ecb_enc_8way_avx(ctx->ctx, srcdst, srcdst); + serpent_fpu_end_rt(ctx); return; } @ arch/x86/crypto/serpent_avx_glue.c:259 @ static void decrypt_callback(void *priv, u8 *srcdst, unsigned int nbytes) struct crypt_priv *ctx = priv; int i; - ctx->fpu_enabled = serpent_fpu_begin(ctx->fpu_enabled, nbytes); - if (nbytes == bsize * SERPENT_PARALLEL_BLOCKS) { + ctx->fpu_enabled = serpent_fpu_begin(ctx->fpu_enabled, nbytes); serpent_ecb_dec_8way_avx(ctx->ctx, srcdst, srcdst); + serpent_fpu_end_rt(ctx); return; } @ arch/x86/crypto/serpent_sse2_glue.c:190 @ struct crypt_priv { bool fpu_enabled; }; +#ifdef CONFIG_PREEMPT_RT_FULL +static void serpent_fpu_end_rt(struct crypt_priv *ctx) +{ + bool fpu_enabled = ctx->fpu_enabled; + + if (!fpu_enabled) + return; + serpent_fpu_end(fpu_enabled); + ctx->fpu_enabled = false; +} + +#else +static void serpent_fpu_end_rt(struct crypt_priv *ctx) { } +#endif + static void encrypt_callback(void *priv, u8 *srcdst, unsigned int nbytes) { const unsigned int bsize = SERPENT_BLOCK_SIZE; struct crypt_priv *ctx = priv; int i; - ctx->fpu_enabled = serpent_fpu_begin(ctx->fpu_enabled, nbytes); - if (nbytes == bsize * SERPENT_PARALLEL_BLOCKS) { + ctx->fpu_enabled = serpent_fpu_begin(ctx->fpu_enabled, nbytes); serpent_enc_blk_xway(ctx->ctx, srcdst, srcdst); + serpent_fpu_end_rt(ctx); return; } @ arch/x86/crypto/serpent_sse2_glue.c:228 @ static void decrypt_callback(void *priv, u8 *srcdst, unsigned int nbytes) struct crypt_priv *ctx = priv; int i; - ctx->fpu_enabled = serpent_fpu_begin(ctx->fpu_enabled, nbytes); - if (nbytes == bsize * SERPENT_PARALLEL_BLOCKS) { + ctx->fpu_enabled = serpent_fpu_begin(ctx->fpu_enabled, nbytes); serpent_dec_blk_xway(ctx->ctx, srcdst, srcdst); + serpent_fpu_end_rt(ctx); return; } @ arch/x86/crypto/twofish_avx_glue.c:221 @ struct crypt_priv { bool fpu_enabled; }; +#ifdef CONFIG_PREEMPT_RT_FULL +static void twofish_fpu_end_rt(struct crypt_priv *ctx) +{ + bool fpu_enabled = ctx->fpu_enabled; + + if (!fpu_enabled) + return; + twofish_fpu_end(fpu_enabled); + ctx->fpu_enabled = false; +} + +#else +static void twofish_fpu_end_rt(struct crypt_priv *ctx) { } +#endif + static void encrypt_callback(void *priv, u8 *srcdst, unsigned int nbytes) { const unsigned int bsize = TF_BLOCK_SIZE; @ arch/x86/crypto/twofish_avx_glue.c:246 @ static void encrypt_callback(void *priv, u8 *srcdst, unsigned int nbytes) if (nbytes == bsize * TWOFISH_PARALLEL_BLOCKS) { twofish_ecb_enc_8way(ctx->ctx, srcdst, srcdst); + twofish_fpu_end_rt(ctx); return; } - for (i = 0; i < nbytes / (bsize * 3); i++, srcdst += bsize * 3) + for (i = 0; i < nbytes / (bsize * 3); i++, srcdst += bsize * 3) { + kernel_fpu_resched(); twofish_enc_blk_3way(ctx->ctx, srcdst, srcdst); + } + twofish_fpu_end_rt(ctx); nbytes %= bsize * 3; for (i = 0; i < nbytes / bsize; i++, srcdst += bsize) @ arch/x86/crypto/twofish_avx_glue.c:272 @ static void decrypt_callback(void *priv, u8 *srcdst, unsigned int nbytes) if (nbytes == bsize * TWOFISH_PARALLEL_BLOCKS) { twofish_ecb_dec_8way(ctx->ctx, srcdst, srcdst); + twofish_fpu_end_rt(ctx); return; } - for (i = 0; i < nbytes / (bsize * 3); i++, srcdst += bsize * 3) + for (i = 0; i < nbytes / (bsize * 3); i++, srcdst += bsize * 3) { + kernel_fpu_resched(); twofish_dec_blk_3way(ctx->ctx, srcdst, srcdst); + } + twofish_fpu_end_rt(ctx); nbytes %= bsize * 3; @ arch/x86/entry/common.c:136 @ static long syscall_trace_enter(struct pt_regs *regs) #define EXIT_TO_USERMODE_LOOP_FLAGS \ (_TIF_SIGPENDING | _TIF_NOTIFY_RESUME | _TIF_UPROBE | \ - _TIF_NEED_RESCHED | _TIF_USER_RETURN_NOTIFY | _TIF_PATCH_PENDING) + _TIF_NEED_RESCHED_MASK | _TIF_USER_RETURN_NOTIFY | _TIF_PATCH_PENDING) static void exit_to_usermode_loop(struct pt_regs *regs, u32 cached_flags) { @ arch/x86/entry/common.c:151 @ static void exit_to_usermode_loop(struct pt_regs *regs, u32 cached_flags) /* We have work to do. */ local_irq_enable(); - if (cached_flags & _TIF_NEED_RESCHED) + if (cached_flags & _TIF_NEED_RESCHED_MASK) schedule(); +#ifdef ARCH_RT_DELAYS_SIGNAL_SEND + if (unlikely(current->forced_info.si_signo)) { + struct task_struct *t = current; + force_sig_info(t->forced_info.si_signo, &t->forced_info, t); + t->forced_info.si_signo = 0; + } +#endif if (cached_flags & _TIF_UPROBE) uprobe_notify_resume(regs); @ arch/x86/entry/entry_32.S:353 @ END(ret_from_exception) ENTRY(resume_kernel) DISABLE_INTERRUPTS(CLBR_ANY) .Lneed_resched: + # preempt count == 0 + NEED_RS set? cmpl $0, PER_CPU_VAR(__preempt_count) +#ifndef CONFIG_PREEMPT_LAZY jnz restore_all +#else + jz test_int_off + + # atleast preempt count == 0 ? + cmpl $_PREEMPT_ENABLED,PER_CPU_VAR(__preempt_count) + jne restore_all + + movl PER_CPU_VAR(current_task), %ebp + cmpl $0,TASK_TI_preempt_lazy_count(%ebp) # non-zero preempt_lazy_count ? + jnz restore_all + + testl $_TIF_NEED_RESCHED_LAZY, TASK_TI_flags(%ebp) + jz restore_all +test_int_off: +#endif testl $X86_EFLAGS_IF, PT_EFLAGS(%esp) # interrupts off (exception path) ? jz restore_all call preempt_schedule_irq @ arch/x86/entry/entry_64.S:701 @ GLOBAL(swapgs_restore_regs_and_return_to_usermode) bt $9, EFLAGS(%rsp) /* were interrupts off? */ jnc 1f 0: cmpl $0, PER_CPU_VAR(__preempt_count) +#ifndef CONFIG_PREEMPT_LAZY jnz 1f +#else + jz do_preempt_schedule_irq + + # atleast preempt count == 0 ? + cmpl $_PREEMPT_ENABLED,PER_CPU_VAR(__preempt_count) + jnz 1f + + movq PER_CPU_VAR(current_task), %rcx + cmpl $0, TASK_TI_preempt_lazy_count(%rcx) + jnz 1f + + bt $TIF_NEED_RESCHED_LAZY,TASK_TI_flags(%rcx) + jnc 1f +do_preempt_schedule_irq: +#endif call preempt_schedule_irq jmp 0b 1: @ arch/x86/entry/entry_64.S:1051 @ EXPORT_SYMBOL(native_load_gs_index) jmp 2b .previous +#ifndef CONFIG_PREEMPT_RT_FULL /* Call softirq on interrupt stack. Interrupts are off. */ ENTRY(do_softirq_own_stack) pushq %rbp @ arch/x86/entry/entry_64.S:1062 @ ENTRY(do_softirq_own_stack) leaveq ret ENDPROC(do_softirq_own_stack) +#endif #ifdef CONFIG_XEN idtentry hypervisor_callback xen_do_hypervisor_callback has_error_code=0 @ arch/x86/include/asm/fpu/api.h:28 @ extern void __kernel_fpu_begin(void); extern void __kernel_fpu_end(void); extern void kernel_fpu_begin(void); extern void kernel_fpu_end(void); +extern void kernel_fpu_resched(void); extern bool irq_fpu_usable(void); /* @ arch/x86/include/asm/preempt.h:89 @ static __always_inline void __preempt_count_sub(int val) * a decrement which hits zero means we have no preempt_count and should * reschedule. */ -static __always_inline bool __preempt_count_dec_and_test(void) +static __always_inline bool ____preempt_count_dec_and_test(void) { GEN_UNARY_RMWcc("decl", __preempt_count, __percpu_arg(0), e); } +static __always_inline bool __preempt_count_dec_and_test(void) +{ + if (____preempt_count_dec_and_test()) + return true; +#ifdef CONFIG_PREEMPT_LAZY + if (current_thread_info()->preempt_lazy_count) + return false; + return test_thread_flag(TIF_NEED_RESCHED_LAZY); +#else + return false; +#endif +} + /* * Returns true when we need to resched and can (barring IRQ state). */ static __always_inline bool should_resched(int preempt_offset) { +#ifdef CONFIG_PREEMPT_LAZY + u32 tmp; + + tmp = raw_cpu_read_4(__preempt_count); + if (tmp == preempt_offset) + return true; + + /* preempt count == 0 ? */ + tmp &= ~PREEMPT_NEED_RESCHED; + if (tmp) + return false; + if (current_thread_info()->preempt_lazy_count) + return false; + return test_thread_flag(TIF_NEED_RESCHED_LAZY); +#else return unlikely(raw_cpu_read_4(__preempt_count) == preempt_offset); +#endif } #ifdef CONFIG_PREEMPT @ arch/x86/include/asm/signal.h:31 @ typedef struct { #define SA_IA32_ABI 0x02000000u #define SA_X32_ABI 0x01000000u +/* + * Because some traps use the IST stack, we must keep preemption + * disabled while calling do_trap(), but do_trap() may call + * force_sig_info() which will grab the signal spin_locks for the + * task, which in PREEMPT_RT_FULL are mutexes. By defining + * ARCH_RT_DELAYS_SIGNAL_SEND the force_sig_info() will set + * TIF_NOTIFY_RESUME and set up the signal to be sent on exit of the + * trap. + */ +#if defined(CONFIG_PREEMPT_RT_FULL) +#define ARCH_RT_DELAYS_SIGNAL_SEND +#endif + #ifndef CONFIG_COMPAT typedef sigset_t compat_sigset_t; #endif @ arch/x86/include/asm/stackprotector.h:63 @ */ static __always_inline void boot_init_stack_canary(void) { - u64 canary; + u64 uninitialized_var(canary); u64 tsc; #ifdef CONFIG_X86_64 @ arch/x86/include/asm/stackprotector.h:74 @ static __always_inline void boot_init_stack_canary(void) * of randomness. The TSC only matters for very early init, * there it already has some randomness on most systems. Later * on during the bootup the random pool has true entropy too. + * For preempt-rt we need to weaken the randomness a bit, as + * we can't call into the random generator from atomic context + * due to locking constraints. We just leave canary + * uninitialized and use the TSC based randomness on top of it. */ +#ifndef CONFIG_PREEMPT_RT_FULL get_random_bytes(&canary, sizeof(canary)); +#endif tsc = rdtsc(); canary += tsc + (tsc << 32UL); canary &= CANARY_MASK; @ arch/x86/include/asm/thread_info.h:59 @ struct task_struct; struct thread_info { unsigned long flags; /* low level flags */ u32 status; /* thread synchronous flags */ + int preempt_lazy_count; /* 0 => lazy preemptable + <0 => BUG */ }; #define INIT_THREAD_INFO(tsk) \ { \ .flags = 0, \ + .preempt_lazy_count = 0, \ } #else /* !__ASSEMBLY__ */ #include <asm/asm-offsets.h> +#define GET_THREAD_INFO(reg) \ + _ASM_MOV PER_CPU_VAR(cpu_current_top_of_stack),reg ; \ + _ASM_SUB $(THREAD_SIZE),reg ; + #endif /* @ arch/x86/include/asm/thread_info.h:93 @ struct thread_info { #define TIF_SYSCALL_EMU 6 /* syscall emulation active */ #define TIF_SYSCALL_AUDIT 7 /* syscall auditing active */ #define TIF_SECCOMP 8 /* secure computing */ +#define TIF_NEED_RESCHED_LAZY 9 /* lazy rescheduling necessary */ #define TIF_USER_RETURN_NOTIFY 11 /* notify kernel of userspace return */ #define TIF_UPROBE 12 /* breakpointed or singlestepping */ #define TIF_PATCH_PENDING 13 /* pending live patching update */ @ arch/x86/include/asm/thread_info.h:121 @ struct thread_info { #define _TIF_SYSCALL_EMU (1 << TIF_SYSCALL_EMU) #define _TIF_SYSCALL_AUDIT (1 << TIF_SYSCALL_AUDIT) #define _TIF_SECCOMP (1 << TIF_SECCOMP) +#define _TIF_NEED_RESCHED_LAZY (1 << TIF_NEED_RESCHED_LAZY) #define _TIF_USER_RETURN_NOTIFY (1 << TIF_USER_RETURN_NOTIFY) #define _TIF_UPROBE (1 << TIF_UPROBE) #define _TIF_PATCH_PENDING (1 << TIF_PATCH_PENDING) @ arch/x86/include/asm/thread_info.h:163 @ struct thread_info { #define _TIF_WORK_CTXSW_PREV (_TIF_WORK_CTXSW|_TIF_USER_RETURN_NOTIFY) #define _TIF_WORK_CTXSW_NEXT (_TIF_WORK_CTXSW) +#define _TIF_NEED_RESCHED_MASK (_TIF_NEED_RESCHED | _TIF_NEED_RESCHED_LAZY) + #define STACK_WARN (THREAD_SIZE/8) /* @ arch/x86/kernel/apic/io_apic.c:1735 @ static bool io_apic_level_ack_pending(struct mp_chip_data *data) static inline bool ioapic_irqd_mask(struct irq_data *data) { /* If we are moving the irq we need to mask it */ - if (unlikely(irqd_is_setaffinity_pending(data))) { + if (unlikely(irqd_is_setaffinity_pending(data) && + !irqd_irq_inprogress(data))) { mask_ioapic_irq(data); return true; } @ arch/x86/kernel/asm-offsets.c:41 @ void common(void) { BLANK(); OFFSET(TASK_TI_flags, task_struct, thread_info.flags); + OFFSET(TASK_TI_preempt_lazy_count, task_struct, thread_info.preempt_lazy_count); OFFSET(TASK_addr_limit, task_struct, thread.addr_limit); BLANK(); @ arch/x86/kernel/asm-offsets.c:98 @ void common(void) { BLANK(); DEFINE(PTREGS_SIZE, sizeof(struct pt_regs)); + DEFINE(_PREEMPT_ENABLED, PREEMPT_ENABLED); /* TLB state for the entry code */ OFFSET(TLB_STATE_user_pcid_flush_mask, tlb_state, user_pcid_flush_mask); @ arch/x86/kernel/fpu/core.c:140 @ void kernel_fpu_end(void) } EXPORT_SYMBOL_GPL(kernel_fpu_end); +void kernel_fpu_resched(void) +{ + WARN_ON_FPU(!this_cpu_read(in_kernel_fpu)); + + if (should_resched(PREEMPT_OFFSET)) { + kernel_fpu_end(); + cond_resched(); + kernel_fpu_begin(); + } +} +EXPORT_SYMBOL_GPL(kernel_fpu_resched); + /* * Save the FPU state (mark it for reload if necessary): * @ arch/x86/kernel/irq_32.c:132 @ void irq_ctx_init(int cpu) cpu, per_cpu(hardirq_stack, cpu), per_cpu(softirq_stack, cpu)); } +#ifndef CONFIG_PREEMPT_RT_FULL void do_softirq_own_stack(void) { struct irq_stack *irqstk; @ arch/x86/kernel/irq_32.c:149 @ void do_softirq_own_stack(void) call_on_stack(__do_softirq, isp); } +#endif bool handle_irq(struct irq_desc *desc, struct pt_regs *regs) { @ arch/x86/kernel/process_32.c:41 @ #include <linux/io.h> #include <linux/kdebug.h> #include <linux/syscalls.h> +#include <linux/highmem.h> #include <asm/pgtable.h> #include <asm/ldt.h> @ arch/x86/kernel/process_32.c:202 @ start_thread(struct pt_regs *regs, unsigned long new_ip, unsigned long new_sp) } EXPORT_SYMBOL_GPL(start_thread); +#ifdef CONFIG_PREEMPT_RT_FULL +static void switch_kmaps(struct task_struct *prev_p, struct task_struct *next_p) +{ + int i; + + /* + * Clear @prev's kmap_atomic mappings + */ + for (i = 0; i < prev_p->kmap_idx; i++) { + int idx = i + KM_TYPE_NR * smp_processor_id(); + pte_t *ptep = kmap_pte - idx; + + kpte_clear_flush(ptep, __fix_to_virt(FIX_KMAP_BEGIN + idx)); + } + /* + * Restore @next_p's kmap_atomic mappings + */ + for (i = 0; i < next_p->kmap_idx; i++) { + int idx = i + KM_TYPE_NR * smp_processor_id(); + + if (!pte_none(next_p->kmap_pte[i])) + set_pte(kmap_pte - idx, next_p->kmap_pte[i]); + } +} +#else +static inline void +switch_kmaps(struct task_struct *prev_p, struct task_struct *next_p) { } +#endif + /* * switch_to(x,y) should switch tasks from x to y. @ arch/x86/kernel/process_32.c:306 @ __switch_to(struct task_struct *prev_p, struct task_struct *next_p) task_thread_info(next_p)->flags & _TIF_WORK_CTXSW_NEXT)) __switch_to_xtra(prev_p, next_p, tss); + switch_kmaps(prev_p, next_p); + /* * Leave lazy mode, flushing any hypercalls made here. * This must be done before restoring TLS segments so @ arch/x86/kvm/lapic.c:2181 @ int kvm_create_lapic(struct kvm_vcpu *vcpu) apic->vcpu = vcpu; hrtimer_init(&apic->lapic_timer.timer, CLOCK_MONOTONIC, - HRTIMER_MODE_ABS_PINNED); + HRTIMER_MODE_ABS_PINNED_HARD); apic->lapic_timer.timer.function = apic_timer_fn; /* @ arch/x86/kvm/x86.c:6389 @ int kvm_arch_init(void *opaque) goto out; } +#ifdef CONFIG_PREEMPT_RT_FULL + if (!boot_cpu_has(X86_FEATURE_CONSTANT_TSC)) { + printk(KERN_ERR "RT requires X86_FEATURE_CONSTANT_TSC\n"); + return -EOPNOTSUPP; + } +#endif + r = kvm_mmu_module_init(); if (r) goto out_free_percpu; @ arch/x86/mm/highmem_32.c:35 @ EXPORT_SYMBOL(kunmap); */ void *kmap_atomic_prot(struct page *page, pgprot_t prot) { + pte_t pte = mk_pte(page, prot); unsigned long vaddr; int idx, type; - preempt_disable(); + preempt_disable_nort(); pagefault_disable(); if (!PageHighMem(page)) @ arch/x86/mm/highmem_32.c:49 @ void *kmap_atomic_prot(struct page *page, pgprot_t prot) idx = type + KM_TYPE_NR*smp_processor_id(); vaddr = __fix_to_virt(FIX_KMAP_BEGIN + idx); BUG_ON(!pte_none(*(kmap_pte-idx))); - set_pte(kmap_pte-idx, mk_pte(page, prot)); +#ifdef CONFIG_PREEMPT_RT_FULL + current->kmap_pte[type] = pte; +#endif + set_pte(kmap_pte-idx, pte); arch_flush_lazy_mmu_mode(); return (void *)vaddr; @ arch/x86/mm/highmem_32.c:95 @ void __kunmap_atomic(void *kvaddr) * is a bad idea also, in case the page changes cacheability * attributes or becomes a protected page in a hypervisor. */ +#ifdef CONFIG_PREEMPT_RT_FULL + current->kmap_pte[type] = __pte(0); +#endif kpte_clear_flush(kmap_pte-idx, vaddr); kmap_atomic_idx_pop(); arch_flush_lazy_mmu_mode(); @ arch/x86/mm/highmem_32.c:110 @ void __kunmap_atomic(void *kvaddr) #endif pagefault_enable(); - preempt_enable(); + preempt_enable_nort(); } EXPORT_SYMBOL(__kunmap_atomic); @ arch/x86/mm/iomap_32.c:59 @ EXPORT_SYMBOL_GPL(iomap_free); void *kmap_atomic_prot_pfn(unsigned long pfn, pgprot_t prot) { + pte_t pte = pfn_pte(pfn, prot); unsigned long vaddr; int idx, type; @ arch/x86/mm/iomap_32.c:69 @ void *kmap_atomic_prot_pfn(unsigned long pfn, pgprot_t prot) type = kmap_atomic_idx_push(); idx = type + KM_TYPE_NR * smp_processor_id(); vaddr = __fix_to_virt(FIX_KMAP_BEGIN + idx); - set_pte(kmap_pte - idx, pfn_pte(pfn, prot)); + WARN_ON(!pte_none(*(kmap_pte - idx))); + +#ifdef CONFIG_PREEMPT_RT_FULL + current->kmap_pte[type] = pte; +#endif + set_pte(kmap_pte - idx, pte); arch_flush_lazy_mmu_mode(); return (void *)vaddr; @ arch/x86/mm/iomap_32.c:122 @ iounmap_atomic(void __iomem *kvaddr) * is a bad idea also, in case the page changes cacheability * attributes or becomes a protected page in a hypervisor. */ +#ifdef CONFIG_PREEMPT_RT_FULL + current->kmap_pte[type] = __pte(0); +#endif kpte_clear_flush(kmap_pte-idx, vaddr); kmap_atomic_idx_pop(); } @ arch/xtensa/include/asm/spinlock_types.h:5 @ #ifndef __ASM_SPINLOCK_TYPES_H #define __ASM_SPINLOCK_TYPES_H -#ifndef __LINUX_SPINLOCK_TYPES_H -# error "please don't include this file directly" -#endif - typedef struct { volatile unsigned int slock; } arch_spinlock_t; @ block/blk-core.c:120 @ void blk_rq_init(struct request_queue *q, struct request *rq) INIT_LIST_HEAD(&rq->queuelist); INIT_LIST_HEAD(&rq->timeout_list); +#ifdef CONFIG_PREEMPT_RT_FULL + INIT_WORK(&rq->work, __blk_mq_complete_request_remote_work); +#endif rq->cpu = -1; rq->q = q; rq->__sector = (sector_t) -1; @ block/blk-core.c:294 @ EXPORT_SYMBOL(blk_start_queue_async); void blk_start_queue(struct request_queue *q) { lockdep_assert_held(q->queue_lock); - WARN_ON(!in_interrupt() && !irqs_disabled()); WARN_ON_ONCE(q->mq_ops); queue_flag_clear(QUEUE_FLAG_STOPPED, q); @ block/blk-core.c:879 @ void blk_queue_exit(struct request_queue *q) percpu_ref_put(&q->q_usage_counter); } +static void blk_queue_usage_counter_release_swork(struct swork_event *sev) +{ + struct request_queue *q = + container_of(sev, struct request_queue, mq_pcpu_wake); + + wake_up_all(&q->mq_freeze_wq); +} + static void blk_queue_usage_counter_release(struct percpu_ref *ref) { struct request_queue *q = container_of(ref, struct request_queue, q_usage_counter); - wake_up_all(&q->mq_freeze_wq); + if (wq_has_sleeper(&q->mq_freeze_wq)) + swork_queue(&q->mq_pcpu_wake); } static void blk_rq_timed_out_timer(struct timer_list *t) @ block/blk-core.c:970 @ struct request_queue *blk_alloc_queue_node(gfp_t gfp_mask, int node_id) __set_bit(QUEUE_FLAG_BYPASS, &q->queue_flags); init_waitqueue_head(&q->mq_freeze_wq); + INIT_SWORK(&q->mq_pcpu_wake, blk_queue_usage_counter_release_swork); /* * Init percpu_ref in atomic mode so that it's faster to shutdown. @ block/blk-core.c:3536 @ static void queue_unplugged(struct request_queue *q, unsigned int depth, blk_run_queue_async(q); else __blk_run_queue(q); - spin_unlock(q->queue_lock); + spin_unlock_irq(q->queue_lock); } static void flush_plug_callbacks(struct blk_plug *plug, bool from_schedule) @ block/blk-core.c:3584 @ EXPORT_SYMBOL(blk_check_plugged); void blk_flush_plug_list(struct blk_plug *plug, bool from_schedule) { struct request_queue *q; - unsigned long flags; struct request *rq; LIST_HEAD(list); unsigned int depth; @ block/blk-core.c:3603 @ void blk_flush_plug_list(struct blk_plug *plug, bool from_schedule) q = NULL; depth = 0; - /* - * Save and disable interrupts here, to avoid doing it for every - * queue lock we have to take. - */ - local_irq_save(flags); while (!list_empty(&list)) { rq = list_entry_rq(list.next); list_del_init(&rq->queuelist); @ block/blk-core.c:3615 @ void blk_flush_plug_list(struct blk_plug *plug, bool from_schedule) queue_unplugged(q, depth, from_schedule); q = rq->q; depth = 0; - spin_lock(q->queue_lock); + spin_lock_irq(q->queue_lock); } /* @ block/blk-core.c:3642 @ void blk_flush_plug_list(struct blk_plug *plug, bool from_schedule) */ if (q) queue_unplugged(q, depth, from_schedule); - - local_irq_restore(flags); } void blk_finish_plug(struct blk_plug *plug) @ block/blk-core.c:3851 @ int __init blk_dev_init(void) if (!kblockd_workqueue) panic("Failed to create kblockd\n"); + BUG_ON(swork_get()); + request_cachep = kmem_cache_create("blkdev_requests", sizeof(struct request), 0, SLAB_PANIC, NULL); @ block/blk-ioc.c:12 @ #include <linux/blkdev.h> #include <linux/slab.h> #include <linux/sched/task.h> +#include <linux/delay.h> #include "blk.h" @ block/blk-ioc.c:122 @ static void ioc_release_fn(struct work_struct *work) spin_unlock(q->queue_lock); } else { spin_unlock_irqrestore(&ioc->lock, flags); - cpu_relax(); + cpu_chill(); spin_lock_irqsave_nested(&ioc->lock, flags, 1); } } @ block/blk-ioc.c:206 @ void put_io_context_active(struct io_context *ioc) spin_unlock(icq->q->queue_lock); } else { spin_unlock_irqrestore(&ioc->lock, flags); - cpu_relax(); + cpu_chill(); goto retry; } } @ block/blk-mq.c:314 @ static struct request *blk_mq_rq_ctx_init(struct blk_mq_alloc_data *data, rq->extra_len = 0; rq->__deadline = 0; +#ifdef CONFIG_PREEMPT_RT_FULL + INIT_WORK(&rq->work, __blk_mq_complete_request_remote_work); +#endif INIT_LIST_HEAD(&rq->timeout_list); rq->timeout = 0; @ block/blk-mq.c:524 @ void blk_mq_end_request(struct request *rq, blk_status_t error) } EXPORT_SYMBOL(blk_mq_end_request); +#ifdef CONFIG_PREEMPT_RT_FULL + +void __blk_mq_complete_request_remote_work(struct work_struct *work) +{ + struct request *rq = container_of(work, struct request, work); + + rq->q->softirq_done_fn(rq); +} + +#else + static void __blk_mq_complete_request_remote(void *data) { struct request *rq = data; rq->q->softirq_done_fn(rq); } +#endif static void __blk_mq_complete_request(struct request *rq) { @ block/blk-mq.c:564 @ static void __blk_mq_complete_request(struct request *rq) return; } - cpu = get_cpu(); + cpu = get_cpu_light(); if (!test_bit(QUEUE_FLAG_SAME_FORCE, &rq->q->queue_flags)) shared = cpus_share_cache(cpu, ctx->cpu); if (cpu != ctx->cpu && !shared && cpu_online(ctx->cpu)) { +#ifdef CONFIG_PREEMPT_RT_FULL + /* + * We could force QUEUE_FLAG_SAME_FORCE then we would not get in + * here. But we could try to invoke it one the CPU like this. + */ + schedule_work_on(ctx->cpu, &rq->work); +#else rq->csd.func = __blk_mq_complete_request_remote; rq->csd.info = rq; rq->csd.flags = 0; smp_call_function_single_async(ctx->cpu, &rq->csd); +#endif } else { rq->q->softirq_done_fn(rq); } - put_cpu(); + put_cpu_light(); } static void hctx_unlock(struct blk_mq_hw_ctx *hctx, int srcu_idx) @ block/blk-mq.c:1431 @ static void __blk_mq_delay_run_hw_queue(struct blk_mq_hw_ctx *hctx, bool async, return; if (!async && !(hctx->flags & BLK_MQ_F_BLOCKING)) { - int cpu = get_cpu(); + int cpu = get_cpu_light(); if (cpumask_test_cpu(cpu, hctx->cpumask)) { __blk_mq_run_hw_queue(hctx); - put_cpu(); + put_cpu_light(); return; } - put_cpu(); + put_cpu_light(); } kblockd_mod_delayed_work_on(blk_mq_hctx_next_cpu(hctx), &hctx->run_work, @ block/blk-mq.c:3140 @ static bool blk_mq_poll_hybrid_sleep(struct request_queue *q, kt = nsecs; mode = HRTIMER_MODE_REL; - hrtimer_init_on_stack(&hs.timer, CLOCK_MONOTONIC, mode); + hrtimer_init_sleeper_on_stack(&hs, CLOCK_MONOTONIC, mode, current); hrtimer_set_expires(&hs.timer, kt); - hrtimer_init_sleeper(&hs, current); do { if (blk_mq_rq_state(rq) == MQ_RQ_COMPLETE) break; @ block/blk-mq.h:150 @ static inline struct blk_mq_ctx *__blk_mq_get_ctx(struct request_queue *q, */ static inline struct blk_mq_ctx *blk_mq_get_ctx(struct request_queue *q) { - return __blk_mq_get_ctx(q, get_cpu()); + return __blk_mq_get_ctx(q, get_cpu_light()); } static inline void blk_mq_put_ctx(struct blk_mq_ctx *ctx) { - put_cpu(); + put_cpu_light(); } struct blk_mq_alloc_data { @ block/blk-softirq.c:56 @ static void trigger_softirq(void *data) raise_softirq_irqoff(BLOCK_SOFTIRQ); local_irq_restore(flags); + preempt_check_resched_rt(); } /* @ block/blk-softirq.c:95 @ static int blk_softirq_cpu_dead(unsigned int cpu) this_cpu_ptr(&blk_cpu_done)); raise_softirq_irqoff(BLOCK_SOFTIRQ); local_irq_enable(); + preempt_check_resched_rt(); return 0; } @ block/blk-softirq.c:148 @ void __blk_complete_request(struct request *req) goto do_local; local_irq_restore(flags); + preempt_check_resched_rt(); } /** @ block/bounce.c:66 @ __initcall(init_emergency_pool); */ static void bounce_copy_vec(struct bio_vec *to, unsigned char *vfrom) { - unsigned long flags; unsigned char *vto; - local_irq_save(flags); vto = kmap_atomic(to->bv_page); memcpy(vto + to->bv_offset, vfrom, to->bv_len); kunmap_atomic(vto); - local_irq_restore(flags); } #else /* CONFIG_HIGHMEM */ @ crypto/algapi.c:729 @ EXPORT_SYMBOL_GPL(crypto_spawn_tfm2); int crypto_register_notifier(struct notifier_block *nb) { - return blocking_notifier_chain_register(&crypto_chain, nb); + return srcu_notifier_chain_register(&crypto_chain, nb); } EXPORT_SYMBOL_GPL(crypto_register_notifier); int crypto_unregister_notifier(struct notifier_block *nb) { - return blocking_notifier_chain_unregister(&crypto_chain, nb); + return srcu_notifier_chain_unregister(&crypto_chain, nb); } EXPORT_SYMBOL_GPL(crypto_unregister_notifier); @ crypto/api.c:35 @ EXPORT_SYMBOL_GPL(crypto_alg_list); DECLARE_RWSEM(crypto_alg_sem); EXPORT_SYMBOL_GPL(crypto_alg_sem); -BLOCKING_NOTIFIER_HEAD(crypto_chain); +SRCU_NOTIFIER_HEAD(crypto_chain); EXPORT_SYMBOL_GPL(crypto_chain); static struct crypto_alg *crypto_larval_wait(struct crypto_alg *alg); @ crypto/api.c:240 @ int crypto_probing_notify(unsigned long val, void *v) { int ok; - ok = blocking_notifier_call_chain(&crypto_chain, val, v); + ok = srcu_notifier_call_chain(&crypto_chain, val, v); if (ok == NOTIFY_DONE) { request_module("cryptomgr"); - ok = blocking_notifier_call_chain(&crypto_chain, val, v); + ok = srcu_notifier_call_chain(&crypto_chain, val, v); } return ok; @ crypto/internal.h:47 @ struct crypto_larval { extern struct list_head crypto_alg_list; extern struct rw_semaphore crypto_alg_sem; -extern struct blocking_notifier_head crypto_chain; +extern struct srcu_notifier_head crypto_chain; #ifdef CONFIG_PROC_FS void __init crypto_init_proc(void); @ crypto/internal.h:142 @ static inline int crypto_is_moribund(struct crypto_alg *alg) static inline void crypto_notify(unsigned long val, void *v) { - blocking_notifier_call_chain(&crypto_chain, val, v); + srcu_notifier_call_chain(&crypto_chain, val, v); } #endif /* _CRYPTO_INTERNAL_H */ @ drivers/acpi/acpica/acglobal.h:119 @ ACPI_GLOBAL(u8, acpi_gbl_global_lock_pending); * interrupt level */ ACPI_GLOBAL(acpi_spinlock, acpi_gbl_gpe_lock); /* For GPE data structs and registers */ -ACPI_GLOBAL(acpi_spinlock, acpi_gbl_hardware_lock); /* For ACPI H/W except GPE registers */ +ACPI_GLOBAL(acpi_raw_spinlock, acpi_gbl_hardware_lock); /* For ACPI H/W except GPE registers */ ACPI_GLOBAL(acpi_spinlock, acpi_gbl_reference_count_lock); /* Mutex for _OSI support */ @ drivers/acpi/acpica/hwregs.c:429 @ acpi_status acpi_hw_clear_acpi_status(void) ACPI_BITMASK_ALL_FIXED_STATUS, ACPI_FORMAT_UINT64(acpi_gbl_xpm1a_status.address))); - lock_flags = acpi_os_acquire_lock(acpi_gbl_hardware_lock); + lock_flags = acpi_os_acquire_raw_lock(acpi_gbl_hardware_lock); /* Clear the fixed events in PM1 A/B */ status = acpi_hw_register_write(ACPI_REGISTER_PM1_STATUS, ACPI_BITMASK_ALL_FIXED_STATUS); - acpi_os_release_lock(acpi_gbl_hardware_lock, lock_flags); + acpi_os_release_raw_lock(acpi_gbl_hardware_lock, lock_flags); if (ACPI_FAILURE(status)) { goto exit; @ drivers/acpi/acpica/hwxface.c:264 @ acpi_status acpi_write_bit_register(u32 register_id, u32 value) return_ACPI_STATUS(AE_BAD_PARAMETER); } - lock_flags = acpi_os_acquire_lock(acpi_gbl_hardware_lock); + lock_flags = acpi_os_acquire_raw_lock(acpi_gbl_hardware_lock); /* * At this point, we know that the parent register is one of the @ drivers/acpi/acpica/hwxface.c:325 @ acpi_status acpi_write_bit_register(u32 register_id, u32 value) unlock_and_exit: - acpi_os_release_lock(acpi_gbl_hardware_lock, lock_flags); + acpi_os_release_raw_lock(acpi_gbl_hardware_lock, lock_flags); return_ACPI_STATUS(status); } @ drivers/acpi/acpica/utmutex.c:91 @ acpi_status acpi_ut_mutex_initialize(void) return_ACPI_STATUS (status); } - status = acpi_os_create_lock (&acpi_gbl_hardware_lock); + status = acpi_os_create_raw_lock(&acpi_gbl_hardware_lock); if (ACPI_FAILURE (status)) { return_ACPI_STATUS (status); } @ drivers/acpi/acpica/utmutex.c:148 @ void acpi_ut_mutex_terminate(void) /* Delete the spinlocks */ acpi_os_delete_lock(acpi_gbl_gpe_lock); - acpi_os_delete_lock(acpi_gbl_hardware_lock); + acpi_os_delete_raw_lock(acpi_gbl_hardware_lock); acpi_os_delete_lock(acpi_gbl_reference_count_lock); /* Delete the reader/writer lock */ @ drivers/ata/libata-sff.c:660 @ unsigned int ata_sff_data_xfer32(struct ata_queued_cmd *qc, unsigned char *buf, } EXPORT_SYMBOL_GPL(ata_sff_data_xfer32); -/** - * ata_sff_data_xfer_noirq - Transfer data by PIO - * @qc: queued command - * @buf: data buffer - * @buflen: buffer length - * @rw: read/write - * - * Transfer data from/to the device data register by PIO. Do the - * transfer with interrupts disabled. - * - * LOCKING: - * Inherited from caller. - * - * RETURNS: - * Bytes consumed. - */ -unsigned int ata_sff_data_xfer_noirq(struct ata_queued_cmd *qc, unsigned char *buf, - unsigned int buflen, int rw) -{ - unsigned long flags; - unsigned int consumed; - - local_irq_save(flags); - consumed = ata_sff_data_xfer32(qc, buf, buflen, rw); - local_irq_restore(flags); - - return consumed; -} -EXPORT_SYMBOL_GPL(ata_sff_data_xfer_noirq); - /** * ata_pio_sector - Transfer a sector of data. * @qc: Command on going @ drivers/ata/pata_cmd640.c:181 @ static struct scsi_host_template cmd640_sht = { static struct ata_port_operations cmd640_port_ops = { .inherits = &ata_sff_port_ops, /* In theory xfer_noirq is not needed once we kill the prefetcher */ - .sff_data_xfer = ata_sff_data_xfer_noirq, + .sff_data_xfer = ata_sff_data_xfer32, .sff_irq_check = cmd640_sff_irq_check, .qc_issue = cmd640_qc_issue, .cable_detect = ata_cable_40wire, @ drivers/ata/pata_icside.c:327 @ static struct ata_port_operations pata_icside_port_ops = { .inherits = &ata_bmdma_port_ops, /* no need to build any PRD tables for DMA */ .qc_prep = ata_noop_qc_prep, - .sff_data_xfer = ata_sff_data_xfer_noirq, + .sff_data_xfer = ata_sff_data_xfer32, .bmdma_setup = pata_icside_bmdma_setup, .bmdma_start = pata_icside_bmdma_start, .bmdma_stop = pata_icside_bmdma_stop, @ drivers/ata/pata_imx.c:105 @ static struct scsi_host_template pata_imx_sht = { static struct ata_port_operations pata_imx_port_ops = { .inherits = &ata_sff_port_ops, - .sff_data_xfer = ata_sff_data_xfer_noirq, + .sff_data_xfer = ata_sff_data_xfer32, .cable_detect = ata_cable_unknown, .set_piomode = pata_imx_set_piomode, }; @ drivers/ata/pata_legacy.c:249 @ static const struct ata_port_operations legacy_base_port_ops = { static struct ata_port_operations simple_port_ops = { .inherits = &legacy_base_port_ops, - .sff_data_xfer = ata_sff_data_xfer_noirq, + .sff_data_xfer = ata_sff_data_xfer32, }; static struct ata_port_operations legacy_port_ops = { .inherits = &legacy_base_port_ops, - .sff_data_xfer = ata_sff_data_xfer_noirq, + .sff_data_xfer = ata_sff_data_xfer32, .set_mode = legacy_set_mode, }; @ drivers/ata/pata_legacy.c:344 @ static unsigned int pdc_data_xfer_vlb(struct ata_queued_cmd *qc, } local_irq_restore(flags); } else - buflen = ata_sff_data_xfer_noirq(qc, buf, buflen, rw); + buflen = ata_sff_data_xfer32(qc, buf, buflen, rw); return buflen; } @ drivers/ata/pata_palmld.c:47 @ static struct scsi_host_template palmld_sht = { static struct ata_port_operations palmld_port_ops = { .inherits = &ata_sff_port_ops, - .sff_data_xfer = ata_sff_data_xfer_noirq, + .sff_data_xfer = ata_sff_data_xfer32, .cable_detect = ata_cable_40wire, }; @ drivers/ata/pata_pcmcia.c:154 @ static struct scsi_host_template pcmcia_sht = { static struct ata_port_operations pcmcia_port_ops = { .inherits = &ata_sff_port_ops, - .sff_data_xfer = ata_sff_data_xfer_noirq, + .sff_data_xfer = ata_sff_data_xfer32, .cable_detect = ata_cable_40wire, .set_mode = pcmcia_set_mode, }; @ drivers/ata/pata_platform.c:52 @ static struct scsi_host_template pata_platform_sht = { static struct ata_port_operations pata_platform_port_ops = { .inherits = &ata_sff_port_ops, - .sff_data_xfer = ata_sff_data_xfer_noirq, + .sff_data_xfer = ata_sff_data_xfer32, .cable_detect = ata_cable_unknown, .set_mode = pata_platform_set_mode, }; @ drivers/ata/pata_via.c:474 @ static struct ata_port_operations via_port_ops = { static struct ata_port_operations via_port_ops_noirq = { .inherits = &via_port_ops, - .sff_data_xfer = ata_sff_data_xfer_noirq, + .sff_data_xfer = ata_sff_data_xfer32, }; /** @ drivers/base/power/wakeup.c:60 @ static void split_counters(unsigned int *cnt, unsigned int *inpr) /* A preserved old value of the events counter. */ static unsigned int saved_count; -static DEFINE_SPINLOCK(events_lock); +static DEFINE_RAW_SPINLOCK(events_lock); static void pm_wakeup_timer_fn(struct timer_list *t); @ drivers/base/power/wakeup.c:188 @ void wakeup_source_add(struct wakeup_source *ws) ws->active = false; ws->last_time = ktime_get(); - spin_lock_irqsave(&events_lock, flags); + raw_spin_lock_irqsave(&events_lock, flags); list_add_rcu(&ws->entry, &wakeup_sources); - spin_unlock_irqrestore(&events_lock, flags); + raw_spin_unlock_irqrestore(&events_lock, flags); } EXPORT_SYMBOL_GPL(wakeup_source_add); @ drivers/base/power/wakeup.c:205 @ void wakeup_source_remove(struct wakeup_source *ws) if (WARN_ON(!ws)) return; - spin_lock_irqsave(&events_lock, flags); + raw_spin_lock_irqsave(&events_lock, flags); list_del_rcu(&ws->entry); - spin_unlock_irqrestore(&events_lock, flags); + raw_spin_unlock_irqrestore(&events_lock, flags); synchronize_srcu(&wakeup_srcu); } EXPORT_SYMBOL_GPL(wakeup_source_remove); @ drivers/base/power/wakeup.c:846 @ bool pm_wakeup_pending(void) unsigned long flags; bool ret = false; - spin_lock_irqsave(&events_lock, flags); + raw_spin_lock_irqsave(&events_lock, flags); if (events_check_enabled) { unsigned int cnt, inpr; @ drivers/base/power/wakeup.c:854 @ bool pm_wakeup_pending(void) ret = (cnt != saved_count || inpr > 0); events_check_enabled = !ret; } - spin_unlock_irqrestore(&events_lock, flags); + raw_spin_unlock_irqrestore(&events_lock, flags); if (ret) { pr_info("PM: Wakeup pending, aborting suspend\n"); @ drivers/base/power/wakeup.c:943 @ bool pm_save_wakeup_count(unsigned int count) unsigned long flags; events_check_enabled = false; - spin_lock_irqsave(&events_lock, flags); + raw_spin_lock_irqsave(&events_lock, flags); split_counters(&cnt, &inpr); if (cnt == count && inpr == 0) { saved_count = count; events_check_enabled = true; } - spin_unlock_irqrestore(&events_lock, flags); + raw_spin_unlock_irqrestore(&events_lock, flags); return events_check_enabled; } @ drivers/block/zram/zcomp.c:119 @ ssize_t zcomp_available_show(const char *comp, char *buf) struct zcomp_strm *zcomp_stream_get(struct zcomp *comp) { - return *get_cpu_ptr(comp->stream); + struct zcomp_strm *zstrm; + + zstrm = *get_local_ptr(comp->stream); + spin_lock(&zstrm->zcomp_lock); + return zstrm; } void zcomp_stream_put(struct zcomp *comp) { - put_cpu_ptr(comp->stream); + struct zcomp_strm *zstrm; + + zstrm = *this_cpu_ptr(comp->stream); + spin_unlock(&zstrm->zcomp_lock); + put_local_ptr(zstrm); } int zcomp_compress(struct zcomp_strm *zstrm, @ drivers/block/zram/zcomp.c:182 @ int zcomp_cpu_up_prepare(unsigned int cpu, struct hlist_node *node) pr_err("Can't allocate a compression stream\n"); return -ENOMEM; } + spin_lock_init(&zstrm->zcomp_lock); *per_cpu_ptr(comp->stream, cpu) = zstrm; return 0; } @ drivers/block/zram/zcomp.h:17 @ struct zcomp_strm { /* compression/decompression buffer */ void *buffer; struct crypto_comp *tfm; + spinlock_t zcomp_lock; }; /* dynamic per-device compression frontend */ @ drivers/block/zram/zram_drv.c:751 @ static DEVICE_ATTR_RO(io_stat); static DEVICE_ATTR_RO(mm_stat); static DEVICE_ATTR_RO(debug_stat); +#ifdef CONFIG_PREEMPT_RT_BASE +static void zram_meta_init_table_locks(struct zram *zram, size_t num_pages) +{ + size_t index; + + for (index = 0; index < num_pages; index++) + spin_lock_init(&zram->table[index].lock); +} + +static void zram_slot_lock(struct zram *zram, u32 index) +{ + spin_lock(&zram->table[index].lock); + __set_bit(ZRAM_ACCESS, &zram->table[index].value); +} + +static void zram_slot_unlock(struct zram *zram, u32 index) +{ + __clear_bit(ZRAM_ACCESS, &zram->table[index].value); + spin_unlock(&zram->table[index].lock); +} + +#else +static void zram_meta_init_table_locks(struct zram *zram, size_t num_pages) { } + static void zram_slot_lock(struct zram *zram, u32 index) { bit_spin_lock(ZRAM_ACCESS, &zram->table[index].value); @ drivers/block/zram/zram_drv.c:784 @ static void zram_slot_unlock(struct zram *zram, u32 index) { bit_spin_unlock(ZRAM_ACCESS, &zram->table[index].value); } +#endif static void zram_meta_free(struct zram *zram, u64 disksize) { @ drivers/block/zram/zram_drv.c:814 @ static bool zram_meta_alloc(struct zram *zram, u64 disksize) return false; } + zram_meta_init_table_locks(zram, num_pages); return true; } @ drivers/block/zram/zram_drv.c:866 @ static int __zram_bvec_read(struct zram *zram, struct page *page, u32 index, unsigned long handle; unsigned int size; void *src, *dst; + struct zcomp_strm *zstrm; if (zram_wb_enabled(zram)) { zram_slot_lock(zram, index); @ drivers/block/zram/zram_drv.c:901 @ static int __zram_bvec_read(struct zram *zram, struct page *page, u32 index, size = zram_get_obj_size(zram, index); + zstrm = zcomp_stream_get(zram->comp); src = zs_map_object(zram->mem_pool, handle, ZS_MM_RO); if (size == PAGE_SIZE) { dst = kmap_atomic(page); @ drivers/block/zram/zram_drv.c:909 @ static int __zram_bvec_read(struct zram *zram, struct page *page, u32 index, kunmap_atomic(dst); ret = 0; } else { - struct zcomp_strm *zstrm = zcomp_stream_get(zram->comp); dst = kmap_atomic(page); ret = zcomp_decompress(zstrm, src, size, dst); kunmap_atomic(dst); - zcomp_stream_put(zram->comp); } zs_unmap_object(zram->mem_pool, handle); + zcomp_stream_put(zram->comp); zram_slot_unlock(zram, index); /* Should NEVER happen. Return bio error if it does. */ @ drivers/block/zram/zram_drv.h:80 @ struct zram_table_entry { unsigned long element; }; unsigned long value; +#ifdef CONFIG_PREEMPT_RT_BASE + spinlock_t lock; +#endif }; struct zram_stats { @ drivers/char/random.c:268 @ #include <linux/syscalls.h> #include <linux/completion.h> #include <linux/uuid.h> +#include <linux/locallock.h> #include <crypto/chacha20.h> #include <asm/processor.h> @ drivers/char/random.c:1126 @ static void add_timer_randomness(struct timer_rand_state *state, unsigned num) } sample; long delta, delta2, delta3; - preempt_disable(); - sample.jiffies = jiffies; sample.cycles = random_get_entropy(); sample.num = num; @ drivers/char/random.c:1166 @ static void add_timer_randomness(struct timer_rand_state *state, unsigned num) */ credit_entropy_bits(r, min_t(int, fls(delta>>1), 11)); } - preempt_enable(); } void add_input_randomness(unsigned int type, unsigned int code, @ drivers/char/random.c:1222 @ static __u32 get_reg(struct fast_pool *f, struct pt_regs *regs) return *ptr; } -void add_interrupt_randomness(int irq, int irq_flags) +void add_interrupt_randomness(int irq, int irq_flags, __u64 ip) { struct entropy_store *r; struct fast_pool *fast_pool = this_cpu_ptr(&irq_randomness); - struct pt_regs *regs = get_irq_regs(); unsigned long now = jiffies; cycles_t cycles = random_get_entropy(); __u32 c_high, j_high; - __u64 ip; unsigned long seed; int credit = 0; if (cycles == 0) - cycles = get_reg(fast_pool, regs); + cycles = get_reg(fast_pool, NULL); c_high = (sizeof(cycles) > 4) ? cycles >> 32 : 0; j_high = (sizeof(now) > 4) ? now >> 32 : 0; fast_pool->pool[0] ^= cycles ^ j_high ^ irq; fast_pool->pool[1] ^= now ^ c_high; - ip = regs ? instruction_pointer(regs) : _RET_IP_; + if (!ip) + ip = _RET_IP_; fast_pool->pool[2] ^= ip; fast_pool->pool[3] ^= (sizeof(ip) > 4) ? ip >> 32 : - get_reg(fast_pool, regs); + get_reg(fast_pool, NULL); fast_mix(fast_pool); add_interrupt_bench(cycles); @ drivers/char/random.c:2192 @ static rwlock_t batched_entropy_reset_lock = __RW_LOCK_UNLOCKED(batched_entropy_ * at any point prior. */ static DEFINE_PER_CPU(struct batched_entropy, batched_entropy_u64); +static DEFINE_LOCAL_IRQ_LOCK(batched_entropy_u64_lock); u64 get_random_u64(void) { u64 ret; @ drivers/char/random.c:2213 @ u64 get_random_u64(void) warn_unseeded_randomness(&previous); use_lock = READ_ONCE(crng_init) < 2; - batch = &get_cpu_var(batched_entropy_u64); + batch = &get_locked_var(batched_entropy_u64_lock, batched_entropy_u64); if (use_lock) read_lock_irqsave(&batched_entropy_reset_lock, flags); if (batch->position % ARRAY_SIZE(batch->entropy_u64) == 0) { @ drivers/char/random.c:2223 @ u64 get_random_u64(void) ret = batch->entropy_u64[batch->position++]; if (use_lock) read_unlock_irqrestore(&batched_entropy_reset_lock, flags); - put_cpu_var(batched_entropy_u64); + put_locked_var(batched_entropy_u64_lock, batched_entropy_u64); return ret; } EXPORT_SYMBOL(get_random_u64); static DEFINE_PER_CPU(struct batched_entropy, batched_entropy_u32); +static DEFINE_LOCAL_IRQ_LOCK(batched_entropy_u32_lock); u32 get_random_u32(void) { u32 ret; @ drivers/char/random.c:2244 @ u32 get_random_u32(void) warn_unseeded_randomness(&previous); use_lock = READ_ONCE(crng_init) < 2; - batch = &get_cpu_var(batched_entropy_u32); + batch = &get_locked_var(batched_entropy_u32_lock, batched_entropy_u32); if (use_lock) read_lock_irqsave(&batched_entropy_reset_lock, flags); if (batch->position % ARRAY_SIZE(batch->entropy_u32) == 0) { @ drivers/char/random.c:2254 @ u32 get_random_u32(void) ret = batch->entropy_u32[batch->position++]; if (use_lock) read_unlock_irqrestore(&batched_entropy_reset_lock, flags); - put_cpu_var(batched_entropy_u32); + put_locked_var(batched_entropy_u32_lock, batched_entropy_u32); return ret; } EXPORT_SYMBOL(get_random_u32); @ drivers/char/tpm/tpm_tis.c:56 @ static inline struct tpm_tis_tcg_phy *to_tpm_tis_tcg_phy(struct tpm_tis_data *da return container_of(data, struct tpm_tis_tcg_phy, priv); } +#ifdef CONFIG_PREEMPT_RT_FULL +/* + * Flushes previous write operations to chip so that a subsequent + * ioread*()s won't stall a cpu. + */ +static inline void tpm_tis_flush(void __iomem *iobase) +{ + ioread8(iobase + TPM_ACCESS(0)); +} +#else +#define tpm_tis_flush(iobase) do { } while (0) +#endif + +static inline void tpm_tis_iowrite8(u8 b, void __iomem *iobase, u32 addr) +{ + iowrite8(b, iobase + addr); + tpm_tis_flush(iobase); +} + +static inline void tpm_tis_iowrite32(u32 b, void __iomem *iobase, u32 addr) +{ + iowrite32(b, iobase + addr); + tpm_tis_flush(iobase); +} + static bool interrupts = true; module_param(interrupts, bool, 0444); MODULE_PARM_DESC(interrupts, "Enable interrupts"); @ drivers/char/tpm/tpm_tis.c:178 @ static int tpm_tcg_write_bytes(struct tpm_tis_data *data, u32 addr, u16 len, struct tpm_tis_tcg_phy *phy = to_tpm_tis_tcg_phy(data); while (len--) - iowrite8(*value++, phy->iobase + addr); + tpm_tis_iowrite8(*value++, phy->iobase, addr); return 0; } @ drivers/char/tpm/tpm_tis.c:205 @ static int tpm_tcg_write32(struct tpm_tis_data *data, u32 addr, u32 value) { struct tpm_tis_tcg_phy *phy = to_tpm_tis_tcg_phy(data); - iowrite32(value, phy->iobase + addr); + tpm_tis_iowrite32(value, phy->iobase, addr); return 0; } @ drivers/clocksource/Kconfig:384 @ config ARMV7M_SYSTICK This options enables support for the ARMv7M system timer unit config ATMEL_PIT + bool "Microchip ARM Periodic Interval Timer (PIT)" if COMPILE_TEST select TIMER_OF if OF - def_bool SOC_AT91SAM9 || SOC_SAMA5 + help + This enables build of clocksource and clockevent driver for + the integrated PIT in Microchip ARM SoCs. config ATMEL_ST bool "Atmel ST timer support" if COMPILE_TEST @ drivers/clocksource/Kconfig:398 @ config ATMEL_ST help Support for the Atmel ST timer. +config ATMEL_ARM_TCB_CLKSRC + bool "Microchip ARM TC Block" if COMPILE_TEST + select REGMAP_MMIO + depends on GENERIC_CLOCKEVENTS + help + This enables build of clocksource and clockevent driver for + the integrated Timer Counter Blocks in Microchip ARM SoCs. + config CLKSRC_METAG_GENERIC def_bool y if METAG help @ drivers/clocksource/Makefile:6 @ obj-$(CONFIG_TIMER_OF) += timer-of.o obj-$(CONFIG_TIMER_PROBE) += timer-probe.o obj-$(CONFIG_ATMEL_PIT) += timer-atmel-pit.o obj-$(CONFIG_ATMEL_ST) += timer-atmel-st.o -obj-$(CONFIG_ATMEL_TCB_CLKSRC) += tcb_clksrc.o +obj-$(CONFIG_ATMEL_TCB_CLKSRC) += tcb_clksrc.o +obj-$(CONFIG_ATMEL_ARM_TCB_CLKSRC) += timer-atmel-tcb.o obj-$(CONFIG_X86_PM_TIMER) += acpi_pm.o obj-$(CONFIG_SCx200HR_TIMER) += scx200_hrt.o obj-$(CONFIG_CS5535_CLOCK_EVENT_SRC) += cs5535-clockevt.o @ drivers/clocksource/tcb_clksrc.c:28 @ * this 32 bit free-running counter. the second channel is not used. * * - The third channel may be used to provide a 16-bit clockevent - * source, used in either periodic or oneshot mode. This runs - * at 32 KiHZ, and can handle delays of up to two seconds. + * source, used in either periodic or oneshot mode. * * A boot clocksource and clockevent source are also currently needed, * unless the relevant platforms (ARM/AT91, AVR32/AT32) are changed so @ drivers/clocksource/tcb_clksrc.c:128 @ static struct clocksource clksrc = { struct tc_clkevt_device { struct clock_event_device clkevt; struct clk *clk; + bool clk_enabled; + u32 freq; void __iomem *regs; }; @ drivers/clocksource/tcb_clksrc.c:138 @ static struct tc_clkevt_device *to_tc_clkevt(struct clock_event_device *clkevt) return container_of(clkevt, struct tc_clkevt_device, clkevt); } -/* For now, we always use the 32K clock ... this optimizes for NO_HZ, - * because using one of the divided clocks would usually mean the - * tick rate can never be less than several dozen Hz (vs 0.5 Hz). - * - * A divided clock could be good for high resolution timers, since - * 30.5 usec resolution can seem "low". - */ static u32 timer_clock; +static void tc_clk_disable(struct clock_event_device *d) +{ + struct tc_clkevt_device *tcd = to_tc_clkevt(d); + + clk_disable(tcd->clk); + tcd->clk_enabled = false; +} + +static void tc_clk_enable(struct clock_event_device *d) +{ + struct tc_clkevt_device *tcd = to_tc_clkevt(d); + + if (tcd->clk_enabled) + return; + clk_enable(tcd->clk); + tcd->clk_enabled = true; +} + static int tc_shutdown(struct clock_event_device *d) { struct tc_clkevt_device *tcd = to_tc_clkevt(d); @ drivers/clocksource/tcb_clksrc.c:165 @ static int tc_shutdown(struct clock_event_device *d) writel(0xff, regs + ATMEL_TC_REG(2, IDR)); writel(ATMEL_TC_CLKDIS, regs + ATMEL_TC_REG(2, CCR)); + return 0; +} + +static int tc_shutdown_clk_off(struct clock_event_device *d) +{ + tc_shutdown(d); if (!clockevent_state_detached(d)) - clk_disable(tcd->clk); + tc_clk_disable(d); return 0; } @ drivers/clocksource/tcb_clksrc.c:185 @ static int tc_set_oneshot(struct clock_event_device *d) if (clockevent_state_oneshot(d) || clockevent_state_periodic(d)) tc_shutdown(d); - clk_enable(tcd->clk); + tc_clk_enable(d); - /* slow clock, count up to RC, then irq and stop */ + /* count up to RC, then irq and stop */ writel(timer_clock | ATMEL_TC_CPCSTOP | ATMEL_TC_WAVE | ATMEL_TC_WAVESEL_UP_AUTO, regs + ATMEL_TC_REG(2, CMR)); writel(ATMEL_TC_CPCS, regs + ATMEL_TC_REG(2, IER)); @ drivers/clocksource/tcb_clksrc.c:207 @ static int tc_set_periodic(struct clock_event_device *d) /* By not making the gentime core emulate periodic mode on top * of oneshot, we get lower overhead and improved accuracy. */ - clk_enable(tcd->clk); + tc_clk_enable(d); - /* slow clock, count up to RC, then irq and restart */ + /* count up to RC, then irq and restart */ writel(timer_clock | ATMEL_TC_WAVE | ATMEL_TC_WAVESEL_UP_AUTO, regs + ATMEL_TC_REG(2, CMR)); - writel((32768 + HZ / 2) / HZ, tcaddr + ATMEL_TC_REG(2, RC)); + writel((tcd->freq + HZ / 2) / HZ, tcaddr + ATMEL_TC_REG(2, RC)); /* Enable clock and interrupts on RC compare */ writel(ATMEL_TC_CPCS, regs + ATMEL_TC_REG(2, IER)); @ drivers/clocksource/tcb_clksrc.c:239 @ static struct tc_clkevt_device clkevt = { .features = CLOCK_EVT_FEAT_PERIODIC | CLOCK_EVT_FEAT_ONESHOT, /* Should be lower than at91rm9200's system timer */ +#ifdef CONFIG_ATMEL_TCB_CLKSRC_USE_SLOW_CLOCK .rating = 125, +#else + .rating = 200, +#endif .set_next_event = tc_next_event, - .set_state_shutdown = tc_shutdown, + .set_state_shutdown = tc_shutdown_clk_off, .set_state_periodic = tc_set_periodic, .set_state_oneshot = tc_set_oneshot, }, @ drivers/clocksource/tcb_clksrc.c:265 @ static irqreturn_t ch2_irq(int irq, void *handle) return IRQ_NONE; } -static int __init setup_clkevents(struct atmel_tc *tc, int clk32k_divisor_idx) +static int __init setup_clkevents(struct atmel_tc *tc, int divisor_idx) { + unsigned divisor = atmel_tc_divisors[divisor_idx]; int ret; struct clk *t2_clk = tc->clk[2]; int irq = tc->irq[2]; @ drivers/clocksource/tcb_clksrc.c:288 @ static int __init setup_clkevents(struct atmel_tc *tc, int clk32k_divisor_idx) clkevt.regs = tc->regs; clkevt.clk = t2_clk; - timer_clock = clk32k_divisor_idx; + timer_clock = divisor_idx; + if (!divisor) + clkevt.freq = 32768; + else + clkevt.freq = clk_get_rate(t2_clk) / divisor; clkevt.clkevt.cpumask = cpumask_of(0); @ drivers/clocksource/tcb_clksrc.c:303 @ static int __init setup_clkevents(struct atmel_tc *tc, int clk32k_divisor_idx) return ret; } - clockevents_config_and_register(&clkevt.clkevt, 32768, 1, 0xffff); + clockevents_config_and_register(&clkevt.clkevt, clkevt.freq, 1, 0xffff); return ret; } @ drivers/clocksource/tcb_clksrc.c:440 @ static int __init tcb_clksrc_init(void) goto err_disable_t1; /* channel 2: periodic and oneshot timer support */ +#ifdef CONFIG_ATMEL_TCB_CLKSRC_USE_SLOW_CLOCK ret = setup_clkevents(tc, clk32k_divisor_idx); +#else + ret = setup_clkevents(tc, best_divisor_idx); +#endif if (ret) goto err_unregister_clksrc; @ drivers/clocksource/timer-atmel-tcb.c:4 @ +// SPDX-License-Identifier: GPL-2.0 +#include <linux/clk.h> +#include <linux/clockchips.h> +#include <linux/clocksource.h> +#include <linux/interrupt.h> +#include <linux/kernel.h> +#include <linux/mfd/syscon.h> +#include <linux/of_address.h> +#include <linux/of_irq.h> +#include <linux/regmap.h> +#include <linux/sched_clock.h> +#include <soc/at91/atmel_tcb.h> + +static struct atmel_tcb_clksrc { + struct clocksource clksrc; + struct clock_event_device clkevt; + struct regmap *regmap; + void __iomem *base; + struct clk *clk[2]; + char name[20]; + int channels[2]; + int bits; + int irq; + struct { + u32 cmr; + u32 imr; + u32 rc; + bool clken; + } cache[2]; + u32 bmr_cache; + bool registered; +} tc = { + .clksrc = { + .rating = 200, + .mask = CLOCKSOURCE_MASK(32), + .flags = CLOCK_SOURCE_IS_CONTINUOUS, + }, + .clkevt = { + .features = CLOCK_EVT_FEAT_ONESHOT, + /* Should be lower than at91rm9200's system timer */ + .rating = 125, + }, +}; + +static struct tc_clkevt_device { + struct clock_event_device clkevt; + struct regmap *regmap; + void __iomem *base; + struct clk *slow_clk; + struct clk *clk; + char name[20]; + int channel; + int irq; + struct { + u32 cmr; + u32 imr; + u32 rc; + bool clken; + } cache; + bool registered; +} tce = { + .clkevt = { + .features = CLOCK_EVT_FEAT_PERIODIC | + CLOCK_EVT_FEAT_ONESHOT, + /* + * Should be lower than at91rm9200's system timer + * but higher than tc.clkevt.rating + */ + .rating = 140, + }, +}; + +/* + * Clockevent device using its own channel + */ +static int tc_clkevt2_shutdown(struct clock_event_device *d) +{ + writel(0xff, tce.base + ATMEL_TC_IDR(tce.channel)); + writel(ATMEL_TC_CCR_CLKDIS, tce.base + ATMEL_TC_CCR(tce.channel)); + if (!clockevent_state_detached(d)) + clk_disable(tce.clk); + + return 0; +} + +/* For now, we always use the 32K clock ... this optimizes for NO_HZ, + * because using one of the divided clocks would usually mean the + * tick rate can never be less than several dozen Hz (vs 0.5 Hz). + * + * A divided clock could be good for high resolution timers, since + * 30.5 usec resolution can seem "low". + */ +static int tc_clkevt2_set_oneshot(struct clock_event_device *d) +{ + if (clockevent_state_oneshot(d) || clockevent_state_periodic(d)) + tc_clkevt2_shutdown(d); + + clk_enable(tce.clk); + + /* slow clock, count up to RC, then irq and stop */ + writel(ATMEL_TC_CMR_TCLK(4) | ATMEL_TC_CMR_CPCSTOP | + ATMEL_TC_CMR_WAVE | ATMEL_TC_CMR_WAVESEL_UPRC, + tce.base + ATMEL_TC_CMR(tce.channel)); + writel(ATMEL_TC_CPCS, tce.base + ATMEL_TC_IER(tce.channel)); + + return 0; +} + +static int tc_clkevt2_set_periodic(struct clock_event_device *d) +{ + if (clockevent_state_oneshot(d) || clockevent_state_periodic(d)) + tc_clkevt2_shutdown(d); + + /* By not making the gentime core emulate periodic mode on top + * of oneshot, we get lower overhead and improved accuracy. + */ + clk_enable(tce.clk); + + /* slow clock, count up to RC, then irq and restart */ + writel(ATMEL_TC_CMR_TCLK(4) | ATMEL_TC_CMR_WAVE | + ATMEL_TC_CMR_WAVESEL_UPRC, + tce.base + ATMEL_TC_CMR(tce.channel)); + writel((32768 + HZ / 2) / HZ, tce.base + ATMEL_TC_RC(tce.channel)); + + /* Enable clock and interrupts on RC compare */ + writel(ATMEL_TC_CPCS, tce.base + ATMEL_TC_IER(tce.channel)); + writel(ATMEL_TC_CCR_CLKEN | ATMEL_TC_CCR_SWTRG, + tce.base + ATMEL_TC_CCR(tce.channel)); + + return 0; +} + +static int tc_clkevt2_next_event(unsigned long delta, + struct clock_event_device *d) +{ + writel(delta, tce.base + ATMEL_TC_RC(tce.channel)); + writel(ATMEL_TC_CCR_CLKEN | ATMEL_TC_CCR_SWTRG, + tce.base + ATMEL_TC_CCR(tce.channel)); + + return 0; +} + +static irqreturn_t tc_clkevt2_irq(int irq, void *handle) +{ + unsigned int sr; + + sr = readl(tce.base + ATMEL_TC_SR(tce.channel)); + if (sr & ATMEL_TC_CPCS) { + tce.clkevt.event_handler(&tce.clkevt); + return IRQ_HANDLED; + } + + return IRQ_NONE; +} + +static void tc_clkevt2_suspend(struct clock_event_device *d) +{ + tce.cache.cmr = readl(tce.base + ATMEL_TC_CMR(tce.channel)); + tce.cache.imr = readl(tce.base + ATMEL_TC_IMR(tce.channel)); + tce.cache.rc = readl(tce.base + ATMEL_TC_RC(tce.channel)); + tce.cache.clken = !!(readl(tce.base + ATMEL_TC_SR(tce.channel)) & + ATMEL_TC_CLKSTA); +} + +static void tc_clkevt2_resume(struct clock_event_device *d) +{ + /* Restore registers for the channel, RA and RB are not used */ + writel(tce.cache.cmr, tc.base + ATMEL_TC_CMR(tce.channel)); + writel(tce.cache.rc, tc.base + ATMEL_TC_RC(tce.channel)); + writel(0, tc.base + ATMEL_TC_RA(tce.channel)); + writel(0, tc.base + ATMEL_TC_RB(tce.channel)); + /* Disable all the interrupts */ + writel(0xff, tc.base + ATMEL_TC_IDR(tce.channel)); + /* Reenable interrupts that were enabled before suspending */ + writel(tce.cache.imr, tc.base + ATMEL_TC_IER(tce.channel)); + + /* Start the clock if it was used */ + if (tce.cache.clken) + writel(ATMEL_TC_CCR_CLKEN | ATMEL_TC_CCR_SWTRG, + tc.base + ATMEL_TC_CCR(tce.channel)); +} + +static int __init tc_clkevt_register(struct device_node *node, + struct regmap *regmap, void __iomem *base, + int channel, int irq, int bits) +{ + int ret; + + tce.regmap = regmap; + tce.base = base; + tce.channel = channel; + tce.irq = irq; + + tce.slow_clk = of_clk_get_by_name(node->parent, "slow_clk"); + if (IS_ERR(tce.slow_clk)) + return PTR_ERR(tce.slow_clk); + + ret = clk_prepare_enable(tce.slow_clk); + if (ret) + return ret; + + tce.clk = tcb_clk_get(node, tce.channel); + if (IS_ERR(tce.clk)) { + ret = PTR_ERR(tce.clk); + goto err_slow; + } + + snprintf(tce.name, sizeof(tce.name), "%s:%d", + kbasename(node->parent->full_name), channel); + tce.clkevt.cpumask = cpumask_of(0); + tce.clkevt.name = tce.name; + tce.clkevt.set_next_event = tc_clkevt2_next_event, + tce.clkevt.set_state_shutdown = tc_clkevt2_shutdown, + tce.clkevt.set_state_periodic = tc_clkevt2_set_periodic, + tce.clkevt.set_state_oneshot = tc_clkevt2_set_oneshot, + tce.clkevt.suspend = tc_clkevt2_suspend, + tce.clkevt.resume = tc_clkevt2_resume, + + /* try to enable clk to avoid future errors in mode change */ + ret = clk_prepare_enable(tce.clk); + if (ret) + goto err_slow; + clk_disable(tce.clk); + + clockevents_config_and_register(&tce.clkevt, 32768, 1, BIT(bits) - 1); + + ret = request_irq(tce.irq, tc_clkevt2_irq, IRQF_TIMER | IRQF_SHARED, + tce.clkevt.name, &tce); + if (ret) + goto err_clk; + + tce.registered = true; + + return 0; + +err_clk: + clk_unprepare(tce.clk); +err_slow: + clk_disable_unprepare(tce.slow_clk); + + return ret; +} + +/* + * Clocksource and clockevent using the same channel(s) + */ +static u64 tc_get_cycles(struct clocksource *cs) +{ + u32 lower, upper; + + do { + upper = readl_relaxed(tc.base + ATMEL_TC_CV(tc.channels[1])); + lower = readl_relaxed(tc.base + ATMEL_TC_CV(tc.channels[0])); + } while (upper != readl_relaxed(tc.base + ATMEL_TC_CV(tc.channels[1]))); + + return (upper << 16) | lower; +} + +static u64 tc_get_cycles32(struct clocksource *cs) +{ + return readl_relaxed(tc.base + ATMEL_TC_CV(tc.channels[0])); +} + +static u64 notrace tc_sched_clock_read(void) +{ + return tc_get_cycles(&tc.clksrc); +} + +static u64 notrace tc_sched_clock_read32(void) +{ + return tc_get_cycles32(&tc.clksrc); +} + +static int tcb_clkevt_next_event(unsigned long delta, + struct clock_event_device *d) +{ + u32 old, next, cur; + + + old = readl(tc.base + ATMEL_TC_CV(tc.channels[0])); + next = old + delta; + writel(next, tc.base + ATMEL_TC_RC(tc.channels[0])); + cur = readl(tc.base + ATMEL_TC_CV(tc.channels[0])); + + /* check whether the delta elapsed while setting the register */ + if ((next < old && cur < old && cur > next) || + (next > old && (cur < old || cur > next))) { + /* + * Clear the CPCS bit in the status register to avoid + * generating a spurious interrupt next time a valid + * timer event is configured. + */ + old = readl(tc.base + ATMEL_TC_SR(tc.channels[0])); + return -ETIME; + } + + writel(ATMEL_TC_CPCS, tc.base + ATMEL_TC_IER(tc.channels[0])); + + return 0; +} + +static irqreturn_t tc_clkevt_irq(int irq, void *handle) +{ + unsigned int sr; + + sr = readl(tc.base + ATMEL_TC_SR(tc.channels[0])); + if (sr & ATMEL_TC_CPCS) { + tc.clkevt.event_handler(&tc.clkevt); + return IRQ_HANDLED; + } + + return IRQ_NONE; +} + +static int tcb_clkevt_oneshot(struct clock_event_device *dev) +{ + if (clockevent_state_oneshot(dev)) + return 0; + + /* + * Because both clockevent devices may share the same IRQ, we don't want + * the less likely one to stay requested + */ + return request_irq(tc.irq, tc_clkevt_irq, IRQF_TIMER | IRQF_SHARED, + tc.name, &tc); +} + +static int tcb_clkevt_shutdown(struct clock_event_device *dev) +{ + writel(0xff, tc.base + ATMEL_TC_IDR(tc.channels[0])); + if (tc.bits == 16) + writel(0xff, tc.base + ATMEL_TC_IDR(tc.channels[1])); + + if (!clockevent_state_detached(dev)) + free_irq(tc.irq, &tc); + + return 0; +} + +static void __init tcb_setup_dual_chan(struct atmel_tcb_clksrc *tc, + int mck_divisor_idx) +{ + /* first channel: waveform mode, input mclk/8, clock TIOA on overflow */ + writel(mck_divisor_idx /* likely divide-by-8 */ + | ATMEL_TC_CMR_WAVE + | ATMEL_TC_CMR_WAVESEL_UP /* free-run */ + | ATMEL_TC_CMR_ACPA(SET) /* TIOA rises at 0 */ + | ATMEL_TC_CMR_ACPC(CLEAR), /* (duty cycle 50%) */ + tc->base + ATMEL_TC_CMR(tc->channels[0])); + writel(0x0000, tc->base + ATMEL_TC_RA(tc->channels[0])); + writel(0x8000, tc->base + ATMEL_TC_RC(tc->channels[0])); + writel(0xff, tc->base + ATMEL_TC_IDR(tc->channels[0])); /* no irqs */ + writel(ATMEL_TC_CCR_CLKEN, tc->base + ATMEL_TC_CCR(tc->channels[0])); + + /* second channel: waveform mode, input TIOA */ + writel(ATMEL_TC_CMR_XC(tc->channels[1]) /* input: TIOA */ + | ATMEL_TC_CMR_WAVE + | ATMEL_TC_CMR_WAVESEL_UP, /* free-run */ + tc->base + ATMEL_TC_CMR(tc->channels[1])); + writel(0xff, tc->base + ATMEL_TC_IDR(tc->channels[1])); /* no irqs */ + writel(ATMEL_TC_CCR_CLKEN, tc->base + ATMEL_TC_CCR(tc->channels[1])); + + /* chain both channel, we assume the previous channel */ + regmap_write(tc->regmap, ATMEL_TC_BMR, + ATMEL_TC_BMR_TCXC(1 + tc->channels[1], tc->channels[1])); + /* then reset all the timers */ + regmap_write(tc->regmap, ATMEL_TC_BCR, ATMEL_TC_BCR_SYNC); +} + +static void __init tcb_setup_single_chan(struct atmel_tcb_clksrc *tc, + int mck_divisor_idx) +{ + /* channel 0: waveform mode, input mclk/8 */ + writel(mck_divisor_idx /* likely divide-by-8 */ + | ATMEL_TC_CMR_WAVE + | ATMEL_TC_CMR_WAVESEL_UP, /* free-run */ + tc->base + ATMEL_TC_CMR(tc->channels[0])); + writel(0xff, tc->base + ATMEL_TC_IDR(tc->channels[0])); /* no irqs */ + writel(ATMEL_TC_CCR_CLKEN, tc->base + ATMEL_TC_CCR(tc->channels[0])); + + /* then reset all the timers */ + regmap_write(tc->regmap, ATMEL_TC_BCR, ATMEL_TC_BCR_SYNC); +} + +static void tc_clksrc_suspend(struct clocksource *cs) +{ + int i; + + for (i = 0; i < 1 + (tc.bits == 16); i++) { + tc.cache[i].cmr = readl(tc.base + ATMEL_TC_CMR(tc.channels[i])); + tc.cache[i].imr = readl(tc.base + ATMEL_TC_IMR(tc.channels[i])); + tc.cache[i].rc = readl(tc.base + ATMEL_TC_RC(tc.channels[i])); + tc.cache[i].clken = !!(readl(tc.base + + ATMEL_TC_SR(tc.channels[i])) & + ATMEL_TC_CLKSTA); + } + + if (tc.bits == 16) + regmap_read(tc.regmap, ATMEL_TC_BMR, &tc.bmr_cache); +} + +static void tc_clksrc_resume(struct clocksource *cs) +{ + int i; + + for (i = 0; i < 1 + (tc.bits == 16); i++) { + /* Restore registers for the channel, RA and RB are not used */ + writel(tc.cache[i].cmr, tc.base + ATMEL_TC_CMR(tc.channels[i])); + writel(tc.cache[i].rc, tc.base + ATMEL_TC_RC(tc.channels[i])); + writel(0, tc.base + ATMEL_TC_RA(tc.channels[i])); + writel(0, tc.base + ATMEL_TC_RB(tc.channels[i])); + /* Disable all the interrupts */ + writel(0xff, tc.base + ATMEL_TC_IDR(tc.channels[i])); + /* Reenable interrupts that were enabled before suspending */ + writel(tc.cache[i].imr, tc.base + ATMEL_TC_IER(tc.channels[i])); + + /* Start the clock if it was used */ + if (tc.cache[i].clken) + writel(ATMEL_TC_CCR_CLKEN, tc.base + + ATMEL_TC_CCR(tc.channels[i])); + } + + /* in case of dual channel, chain channels */ + if (tc.bits == 16) + regmap_write(tc.regmap, ATMEL_TC_BMR, tc.bmr_cache); + /* Finally, trigger all the channels*/ + regmap_write(tc.regmap, ATMEL_TC_BCR, ATMEL_TC_BCR_SYNC); +} + +static int __init tcb_clksrc_register(struct device_node *node, + struct regmap *regmap, void __iomem *base, + int channel, int channel1, int irq, + int bits) +{ + u32 rate, divided_rate = 0; + int best_divisor_idx = -1; + int i, err = -1; + u64 (*tc_sched_clock)(void); + + tc.regmap = regmap; + tc.base = base; + tc.channels[0] = channel; + tc.channels[1] = channel1; + tc.irq = irq; + tc.bits = bits; + + tc.clk[0] = tcb_clk_get(node, tc.channels[0]); + if (IS_ERR(tc.clk[0])) + return PTR_ERR(tc.clk[0]); + err = clk_prepare_enable(tc.clk[0]); + if (err) { + pr_debug("can't enable T0 clk\n"); + goto err_clk; + } + + /* How fast will we be counting? Pick something over 5 MHz. */ + rate = (u32)clk_get_rate(tc.clk[0]); + for (i = 0; i < 5; i++) { + unsigned int divisor = atmel_tc_divisors[i]; + unsigned int tmp; + + if (!divisor) + continue; + + tmp = rate / divisor; + pr_debug("TC: %u / %-3u [%d] --> %u\n", rate, divisor, i, tmp); + if (best_divisor_idx > 0) { + if (tmp < 5 * 1000 * 1000) + continue; + } + divided_rate = tmp; + best_divisor_idx = i; + } + + if (tc.bits == 32) { + tc.clksrc.read = tc_get_cycles32; + tcb_setup_single_chan(&tc, best_divisor_idx); + tc_sched_clock = tc_sched_clock_read32; + snprintf(tc.name, sizeof(tc.name), "%s:%d", + kbasename(node->parent->full_name), tc.channels[0]); + } else { + tc.clk[1] = tcb_clk_get(node, tc.channels[1]); + if (IS_ERR(tc.clk[1])) + goto err_disable_t0; + + err = clk_prepare_enable(tc.clk[1]); + if (err) { + pr_debug("can't enable T1 clk\n"); + goto err_clk1; + } + tc.clksrc.read = tc_get_cycles, + tcb_setup_dual_chan(&tc, best_divisor_idx); + tc_sched_clock = tc_sched_clock_read; + snprintf(tc.name, sizeof(tc.name), "%s:%d,%d", + kbasename(node->parent->full_name), tc.channels[0], + tc.channels[1]); + } + + pr_debug("%s at %d.%03d MHz\n", tc.name, + divided_rate / 1000000, + ((divided_rate + 500000) % 1000000) / 1000); + + tc.clksrc.name = tc.name; + tc.clksrc.suspend = tc_clksrc_suspend; + tc.clksrc.resume = tc_clksrc_resume; + + err = clocksource_register_hz(&tc.clksrc, divided_rate); + if (err) + goto err_disable_t1; + + sched_clock_register(tc_sched_clock, 32, divided_rate); + + tc.registered = true; + + /* Set up and register clockevents */ + tc.clkevt.name = tc.name; + tc.clkevt.cpumask = cpumask_of(0); + tc.clkevt.set_next_event = tcb_clkevt_next_event; + tc.clkevt.set_state_oneshot = tcb_clkevt_oneshot; + tc.clkevt.set_state_shutdown = tcb_clkevt_shutdown; + clockevents_config_and_register(&tc.clkevt, divided_rate, 1, + BIT(tc.bits) - 1); + + return 0; + +err_disable_t1: + if (tc.bits == 16) + clk_disable_unprepare(tc.clk[1]); + +err_clk1: + if (tc.bits == 16) + clk_put(tc.clk[1]); + +err_disable_t0: + clk_disable_unprepare(tc.clk[0]); + +err_clk: + clk_put(tc.clk[0]); + + pr_err("%s: unable to register clocksource/clockevent\n", + tc.clksrc.name); + + return err; +} + +static int __init tcb_clksrc_init(struct device_node *node) +{ + const struct of_device_id *match; + const struct atmel_tcb_info *tcb_info; + struct regmap *regmap; + void __iomem *tcb_base; + u32 channel; + int bits, irq, err, chan1 = -1; + + if (tc.registered && tce.registered) + return -ENODEV; + + /* + * The regmap has to be used to access registers that are shared + * between channels on the same TCB but we keep direct IO access for + * the counters to avoid the impact on performance + */ + regmap = syscon_node_to_regmap(node->parent); + if (IS_ERR(regmap)) + return PTR_ERR(regmap); + + tcb_base = of_iomap(node->parent, 0); + if (!tcb_base) { + pr_err("%s +%d %s\n", __FILE__, __LINE__, __func__); + return -ENXIO; + } + + match = of_match_node(atmel_tcb_dt_ids, node->parent); + tcb_info = match->data; + bits = tcb_info->bits; + + err = of_property_read_u32_index(node, "reg", 0, &channel); + if (err) + return err; + + irq = tcb_irq_get(node, channel); + if (irq < 0) + return irq; + + if (tc.registered) + return tc_clkevt_register(node, regmap, tcb_base, channel, irq, + bits); + + if (bits == 16) { + of_property_read_u32_index(node, "reg", 1, &chan1); + if (chan1 == -1) { + if (tce.registered) { + pr_err("%s: clocksource needs two channels\n", + node->parent->full_name); + return -EINVAL; + } else { + return tc_clkevt_register(node, regmap, + tcb_base, channel, + irq, bits); + } + } + } + + return tcb_clksrc_register(node, regmap, tcb_base, channel, chan1, irq, + bits); +} +CLOCKSOURCE_OF_DECLARE(atmel_tcb_clksrc, "atmel,tcb-timer", + tcb_clksrc_init); @ drivers/connector/cn_proc.c:35 @ #include <linux/pid_namespace.h> #include <linux/cn_proc.h> +#include <linux/locallock.h> /* * Size of a cn_msg followed by a proc_event structure. Since the @ drivers/connector/cn_proc.c:58 @ static struct cb_id cn_proc_event_id = { CN_IDX_PROC, CN_VAL_PROC }; /* proc_event_counts is used as the sequence number of the netlink message */ static DEFINE_PER_CPU(__u32, proc_event_counts) = { 0 }; +static DEFINE_LOCAL_IRQ_LOCK(send_msg_lock); static inline void send_msg(struct cn_msg *msg) { - preempt_disable(); + local_lock(send_msg_lock); msg->seq = __this_cpu_inc_return(proc_event_counts) - 1; ((struct proc_event *)msg->data)->cpu = smp_processor_id(); @ drivers/connector/cn_proc.c:75 @ static inline void send_msg(struct cn_msg *msg) */ cn_netlink_send(msg, 0, CN_IDX_PROC, GFP_NOWAIT); - preempt_enable(); + local_unlock(send_msg_lock); } void proc_fork_connector(struct task_struct *task) @ drivers/cpufreq/Kconfig.x86:128 @ config X86_POWERNOW_K7_ACPI config X86_POWERNOW_K8 tristate "AMD Opteron/Athlon64 PowerNow!" - depends on ACPI && ACPI_PROCESSOR && X86_ACPI_CPUFREQ + depends on ACPI && ACPI_PROCESSOR && X86_ACPI_CPUFREQ && !PREEMPT_RT_BASE help This adds the CPUFreq driver for K8/early Opteron/Athlon64 processors. Support for K10 and newer processors is now in acpi-cpufreq. @ drivers/gpu/drm/i915/i915_irq.c:939 @ static bool i915_get_crtc_scanoutpos(struct drm_device *dev, unsigned int pipe, spin_lock_irqsave(&dev_priv->uncore.lock, irqflags); /* preempt_disable_rt() should go right here in PREEMPT_RT patchset. */ + preempt_disable_rt(); /* Get optional system timestamp before query. */ if (stime) @ drivers/gpu/drm/i915/i915_irq.c:991 @ static bool i915_get_crtc_scanoutpos(struct drm_device *dev, unsigned int pipe, *etime = ktime_get(); /* preempt_enable_rt() should go right here in PREEMPT_RT patchset. */ + preempt_enable_rt(); spin_unlock_irqrestore(&dev_priv->uncore.lock, irqflags); @ drivers/gpu/drm/i915/intel_sprite.c:39 @ #include <drm/drm_rect.h> #include <drm/drm_atomic.h> #include <drm/drm_plane_helper.h> +#include <linux/locallock.h> #include "intel_drv.h" #include "intel_frontbuffer.h" #include <drm/i915_drm.h> @ drivers/gpu/drm/i915/intel_sprite.c:78 @ int intel_usecs_to_scanlines(const struct drm_display_mode *adjusted_mode, #define VBLANK_EVASION_TIME_US 100 #endif +static DEFINE_LOCAL_IRQ_LOCK(pipe_update_lock); + /** * intel_pipe_update_start() - start update of a set of display registers * @new_crtc_state: the new crtc state @ drivers/gpu/drm/i915/intel_sprite.c:113 @ void intel_pipe_update_start(const struct intel_crtc_state *new_crtc_state) VBLANK_EVASION_TIME_US); max = vblank_start - 1; - local_irq_disable(); + local_lock_irq(pipe_update_lock); if (min <= 0 || max <= 0) return; @ drivers/gpu/drm/i915/intel_sprite.c:143 @ void intel_pipe_update_start(const struct intel_crtc_state *new_crtc_state) break; } - local_irq_enable(); + local_unlock_irq(pipe_update_lock); timeout = schedule_timeout(timeout); - local_irq_disable(); + local_lock_irq(pipe_update_lock); } finish_wait(wq, &wait); @ drivers/gpu/drm/i915/intel_sprite.c:212 @ void intel_pipe_update_end(struct intel_crtc_state *new_crtc_state) new_crtc_state->base.event = NULL; } - local_irq_enable(); + local_unlock_irq(pipe_update_lock); if (intel_vgpu_active(dev_priv)) return; @ drivers/gpu/drm/radeon/radeon_display.c:1837 @ int radeon_get_crtc_scanoutpos(struct drm_device *dev, unsigned int pipe, struct radeon_device *rdev = dev->dev_private; /* preempt_disable_rt() should go right here in PREEMPT_RT patchset. */ + preempt_disable_rt(); /* Get optional system timestamp before query. */ if (stime) @ drivers/gpu/drm/radeon/radeon_display.c:1930 @ int radeon_get_crtc_scanoutpos(struct drm_device *dev, unsigned int pipe, *etime = ktime_get(); /* preempt_enable_rt() should go right here in PREEMPT_RT patchset. */ + preempt_enable_rt(); /* Decode into vertical and horizontal scanout position. */ *vpos = position & 0x1fff; @ drivers/hv/vmbus_drv.c:976 @ static void vmbus_isr(void) void *page_addr = hv_cpu->synic_event_page; struct hv_message *msg; union hv_synic_event_flags *event; + struct pt_regs *regs = get_irq_regs(); + u64 ip = regs ? instruction_pointer(regs) : 0; bool handled = false; if (unlikely(page_addr == NULL)) @ drivers/hv/vmbus_drv.c:1021 @ static void vmbus_isr(void) tasklet_schedule(&hv_cpu->msg_dpc); } - add_interrupt_randomness(HYPERVISOR_CALLBACK_VECTOR, 0); + add_interrupt_randomness(HYPERVISOR_CALLBACK_VECTOR, 0, ip); } @ drivers/ide/alim15x3.c:326 @ static int init_chipset_ali15x3(struct pci_dev *dev) pci_write_config_byte(dev, 0x53, tmpbyte); } + local_irq_restore(flags); pci_dev_put(north); pci_dev_put(isa_dev); - local_irq_restore(flags); return 0; } @ drivers/ide/ide-io.c:662 @ void ide_timer_expiry (struct timer_list *t) spin_unlock(&hwif->lock); /* disable_irq_nosync ?? */ disable_irq(hwif->irq); - /* local CPU only, as if we were handling an interrupt */ - local_irq_disable(); + if (hwif->polling) { startstop = handler(drive); } else if (drive_is_ready(drive)) { @ drivers/ide/ide-io.c:681 @ void ide_timer_expiry (struct timer_list *t) startstop = ide_error(drive, "irq timeout", hwif->tp_ops->read_status(hwif)); } + /* Disable interrupts again, `handler' might have enabled it */ spin_lock_irq(&hwif->lock); enable_irq(hwif->irq); if (startstop == ide_stopped && hwif->polling == 0) { @ drivers/ide/ide-iops.c:111 @ int __ide_wait_stat(ide_drive_t *drive, u8 good, u8 bad, ide_hwif_t *hwif = drive->hwif; const struct ide_tp_ops *tp_ops = hwif->tp_ops; unsigned long flags; + bool irqs_threaded = force_irqthreads; int i; u8 stat; @ drivers/ide/ide-iops.c:119 @ int __ide_wait_stat(ide_drive_t *drive, u8 good, u8 bad, stat = tp_ops->read_status(hwif); if (stat & ATA_BUSY) { - local_save_flags(flags); - local_irq_enable_in_hardirq(); + if (!irqs_threaded) { + local_save_flags(flags); + local_irq_enable_in_hardirq(); + } timeout += jiffies; while ((stat = tp_ops->read_status(hwif)) & ATA_BUSY) { if (time_after(jiffies, timeout)) { @ drivers/ide/ide-iops.c:135 @ int __ide_wait_stat(ide_drive_t *drive, u8 good, u8 bad, if ((stat & ATA_BUSY) == 0) break; - local_irq_restore(flags); + if (!irqs_threaded) + local_irq_restore(flags); *rstat = stat; return -EBUSY; } } - local_irq_restore(flags); + if (!irqs_threaded) + local_irq_restore(flags); } /* * Allow status to settle, then read it again. @ drivers/ide/ide-taskfile.c:240 @ void ide_pio_bytes(ide_drive_t *drive, struct ide_cmd *cmd, while (len) { unsigned nr_bytes = min(len, cursg->length - cmd->cursg_ofs); - int page_is_high; page = sg_page(cursg); offset = cursg->offset + cmd->cursg_ofs; @ drivers/ide/ide-taskfile.c:250 @ void ide_pio_bytes(ide_drive_t *drive, struct ide_cmd *cmd, nr_bytes = min_t(unsigned, nr_bytes, (PAGE_SIZE - offset)); - page_is_high = PageHighMem(page); - if (page_is_high) - local_irq_save(flags); - buf = kmap_atomic(page) + offset; cmd->nleft -= nr_bytes; @ drivers/ide/ide-taskfile.c:268 @ void ide_pio_bytes(ide_drive_t *drive, struct ide_cmd *cmd, kunmap_atomic(buf); - if (page_is_high) - local_irq_restore(flags); - len -= nr_bytes; } } @ drivers/ide/ide-taskfile.c:408 @ static ide_startstop_t pre_task_out_intr(ide_drive_t *drive, return startstop; } - if ((drive->dev_flags & IDE_DFLAG_UNMASK) == 0) + if (!force_irqthreads && (drive->dev_flags & IDE_DFLAG_UNMASK) == 0) local_irq_disable(); ide_set_handler(drive, &task_pio_intr, WAIT_WORSTCASE); @ drivers/infiniband/hw/hfi1/affinity.c:579 @ int hfi1_get_proc_affinity(int node) struct hfi1_affinity_node *entry; cpumask_var_t diff, hw_thread_mask, available_mask, intrs_mask; const struct cpumask *node_mask, - *proc_mask = ¤t->cpus_allowed; + *proc_mask = current->cpus_ptr; struct hfi1_affinity_node_list *affinity = &node_affinity; struct cpu_mask_set *set = &affinity->proc; @ drivers/infiniband/hw/hfi1/affinity.c:587 @ int hfi1_get_proc_affinity(int node) * check whether process/context affinity has already * been set */ - if (cpumask_weight(proc_mask) == 1) { + if (current->nr_cpus_allowed == 1) { hfi1_cdbg(PROC, "PID %u %s affinity set to CPU %*pbl", current->pid, current->comm, cpumask_pr_args(proc_mask)); @ drivers/infiniband/hw/hfi1/affinity.c:598 @ int hfi1_get_proc_affinity(int node) cpu = cpumask_first(proc_mask); cpumask_set_cpu(cpu, &set->used); goto done; - } else if (cpumask_weight(proc_mask) < cpumask_weight(&set->mask)) { + } else if (current->nr_cpus_allowed < cpumask_weight(&set->mask)) { hfi1_cdbg(PROC, "PID %u %s affinity set to CPU set(s) %*pbl", current->pid, current->comm, cpumask_pr_args(proc_mask)); @ drivers/infiniband/hw/hfi1/sdma.c:858 @ struct sdma_engine *sdma_select_user_engine(struct hfi1_devdata *dd, { struct sdma_rht_node *rht_node; struct sdma_engine *sde = NULL; - const struct cpumask *current_mask = ¤t->cpus_allowed; unsigned long cpu_id; /* * To ensure that always the same sdma engine(s) will be * selected make sure the process is pinned to this CPU only. */ - if (cpumask_weight(current_mask) != 1) + if (current->nr_cpus_allowed != 1) goto out; cpu_id = smp_processor_id(); @ drivers/infiniband/hw/qib/qib_file_ops.c:1141 @ static __poll_t qib_poll(struct file *fp, struct poll_table_struct *pt) static void assign_ctxt_affinity(struct file *fp, struct qib_devdata *dd) { struct qib_filedata *fd = fp->private_data; - const unsigned int weight = cpumask_weight(¤t->cpus_allowed); + const unsigned int weight = current->nr_cpus_allowed; const struct cpumask *local_mask = cpumask_of_pcibus(dd->pcidev->bus); int local_cpu; @ drivers/infiniband/hw/qib/qib_file_ops.c:1622 @ static int qib_assign_ctxt(struct file *fp, const struct qib_user_info *uinfo) ret = find_free_ctxt(i_minor - 1, fp, uinfo); else { int unit; - const unsigned int cpu = cpumask_first(¤t->cpus_allowed); - const unsigned int weight = - cpumask_weight(¤t->cpus_allowed); + const unsigned int cpu = cpumask_first(current->cpus_ptr); + const unsigned int weight = current->nr_cpus_allowed; if (weight == 1 && !test_bit(cpu, qib_cpulist)) if (!find_hca(cpu, &unit) && unit >= 0) @ drivers/infiniband/ulp/ipoib/ipoib_multicast.c:889 @ void ipoib_mcast_restart_task(struct work_struct *work) struct netdev_hw_addr *ha; struct ipoib_mcast *mcast, *tmcast; LIST_HEAD(remove_list); - unsigned long flags; struct ib_sa_mcmember_rec rec; if (!test_bit(IPOIB_FLAG_OPER_UP, &priv->flags)) @ drivers/infiniband/ulp/ipoib/ipoib_multicast.c:900 @ void ipoib_mcast_restart_task(struct work_struct *work) ipoib_dbg_mcast(priv, "restarting multicast task\n"); - local_irq_save(flags); - netif_addr_lock(dev); - spin_lock(&priv->lock); + netif_addr_lock_bh(dev); + spin_lock_irq(&priv->lock); /* * Unfortunately, the networking core only gives us a list of all of @ drivers/infiniband/ulp/ipoib/ipoib_multicast.c:979 @ void ipoib_mcast_restart_task(struct work_struct *work) } } - spin_unlock(&priv->lock); - netif_addr_unlock(dev); - local_irq_restore(flags); + spin_unlock_irq(&priv->lock); + netif_addr_unlock_bh(dev); ipoib_mcast_remove_list(&remove_list); @ drivers/infiniband/ulp/ipoib/ipoib_multicast.c:988 @ void ipoib_mcast_restart_task(struct work_struct *work) * Double check that we are still up */ if (test_bit(IPOIB_FLAG_OPER_UP, &priv->flags)) { - spin_lock_irqsave(&priv->lock, flags); + spin_lock_irq(&priv->lock); __ipoib_mcast_schedule_join_thread(priv, NULL, 0); - spin_unlock_irqrestore(&priv->lock, flags); + spin_unlock_irq(&priv->lock); } } @ drivers/iommu/amd_iommu.c:83 @ */ #define AMD_IOMMU_PGSIZES ((~0xFFFUL) & ~(2ULL << 38)) -static DEFINE_RWLOCK(amd_iommu_devtable_lock); +static DEFINE_SPINLOCK(pd_bitmap_lock); /* List of all available dev_data structures */ -static LIST_HEAD(dev_data_list); -static DEFINE_SPINLOCK(dev_data_list_lock); +static LLIST_HEAD(dev_data_list); LIST_HEAD(ioapic_map); LIST_HEAD(hpet_map); @ drivers/iommu/amd_iommu.c:205 @ static struct dma_ops_domain* to_dma_ops_domain(struct protection_domain *domain static struct iommu_dev_data *alloc_dev_data(u16 devid) { struct iommu_dev_data *dev_data; - unsigned long flags; dev_data = kzalloc(sizeof(*dev_data), GFP_KERNEL); if (!dev_data) return NULL; dev_data->devid = devid; - - spin_lock_irqsave(&dev_data_list_lock, flags); - list_add_tail(&dev_data->dev_data_list, &dev_data_list); - spin_unlock_irqrestore(&dev_data_list_lock, flags); - ratelimit_default_init(&dev_data->rs); + llist_add(&dev_data->dev_data_list, &dev_data_list); return dev_data; } static struct iommu_dev_data *search_dev_data(u16 devid) { struct iommu_dev_data *dev_data; - unsigned long flags; + struct llist_node *node; - spin_lock_irqsave(&dev_data_list_lock, flags); - list_for_each_entry(dev_data, &dev_data_list, dev_data_list) { + if (llist_empty(&dev_data_list)) + return NULL; + + node = dev_data_list.first; + llist_for_each_entry(dev_data, node, dev_data_list) { if (dev_data->devid == devid) - goto out_unlock; + return dev_data; } - dev_data = NULL; - -out_unlock: - spin_unlock_irqrestore(&dev_data_list_lock, flags); - - return dev_data; + return NULL; } static int __last_alias(struct pci_dev *pdev, u16 alias, void *data) @ drivers/iommu/amd_iommu.c:1053 @ static int iommu_queue_command_sync(struct amd_iommu *iommu, unsigned long flags; int ret; - spin_lock_irqsave(&iommu->lock, flags); + raw_spin_lock_irqsave(&iommu->lock, flags); ret = __iommu_queue_command_sync(iommu, cmd, sync); - spin_unlock_irqrestore(&iommu->lock, flags); + raw_spin_unlock_irqrestore(&iommu->lock, flags); return ret; } @ drivers/iommu/amd_iommu.c:1081 @ static int iommu_completion_wait(struct amd_iommu *iommu) build_completion_wait(&cmd, (u64)&iommu->cmd_sem); - spin_lock_irqsave(&iommu->lock, flags); + raw_spin_lock_irqsave(&iommu->lock, flags); iommu->cmd_sem = 0; @ drivers/iommu/amd_iommu.c:1092 @ static int iommu_completion_wait(struct amd_iommu *iommu) ret = wait_on_sem(&iommu->cmd_sem); out_unlock: - spin_unlock_irqrestore(&iommu->lock, flags); + raw_spin_unlock_irqrestore(&iommu->lock, flags); return ret; } @ drivers/iommu/amd_iommu.c:1602 @ static void del_domain_from_list(struct protection_domain *domain) static u16 domain_id_alloc(void) { - unsigned long flags; int id; - write_lock_irqsave(&amd_iommu_devtable_lock, flags); + spin_lock(&pd_bitmap_lock); id = find_first_zero_bit(amd_iommu_pd_alloc_bitmap, MAX_DOMAIN_ID); BUG_ON(id == 0); if (id > 0 && id < MAX_DOMAIN_ID) __set_bit(id, amd_iommu_pd_alloc_bitmap); else id = 0; - write_unlock_irqrestore(&amd_iommu_devtable_lock, flags); + spin_unlock(&pd_bitmap_lock); return id; } static void domain_id_free(int id) { - unsigned long flags; - - write_lock_irqsave(&amd_iommu_devtable_lock, flags); + spin_lock(&pd_bitmap_lock); if (id > 0 && id < MAX_DOMAIN_ID) __clear_bit(id, amd_iommu_pd_alloc_bitmap); - write_unlock_irqrestore(&amd_iommu_devtable_lock, flags); + spin_unlock(&pd_bitmap_lock); } #define DEFINE_FREE_PT_FN(LVL, FN) \ @ drivers/iommu/amd_iommu.c:1879 @ static void clear_dte_entry(u16 devid) amd_iommu_apply_erratum_63(devid); } -static void do_attach(struct iommu_dev_data *dev_data, - struct protection_domain *domain) +/* + * This function does assigns the device visible for the hardware + */ +static void __attach_device(struct iommu_dev_data *dev_data, + struct protection_domain *domain) { struct amd_iommu *iommu; u16 alias; bool ats; + lockdep_assert_held(&domain->lock); + iommu = amd_iommu_rlookup_table[dev_data->devid]; alias = dev_data->alias; ats = dev_data->ats.enabled; @ drivers/iommu/amd_iommu.c:1911 @ static void do_attach(struct iommu_dev_data *dev_data, device_flush_dte(dev_data); } -static void do_detach(struct iommu_dev_data *dev_data) +static void __detach_device(struct iommu_dev_data *dev_data) { struct amd_iommu *iommu; u16 alias; - /* - * First check if the device is still attached. It might already - * be detached from its domain because the generic - * iommu_detach_group code detached it and we try again here in - * our alias handling. - */ - if (!dev_data->domain) - return; + lockdep_assert_held(&dev_data->domain->lock); iommu = amd_iommu_rlookup_table[dev_data->devid]; alias = dev_data->alias; @ drivers/iommu/amd_iommu.c:1936 @ static void do_detach(struct iommu_dev_data *dev_data) device_flush_dte(dev_data); } -/* - * If a device is not yet associated with a domain, this function does - * assigns it visible for the hardware - */ -static int __attach_device(struct iommu_dev_data *dev_data, - struct protection_domain *domain) -{ - int ret; - - /* - * Must be called with IRQs disabled. Warn here to detect early - * when its not. - */ - WARN_ON(!irqs_disabled()); - - /* lock domain */ - spin_lock(&domain->lock); - - ret = -EBUSY; - if (dev_data->domain != NULL) - goto out_unlock; - - /* Attach alias group root */ - do_attach(dev_data, domain); - - ret = 0; - -out_unlock: - - /* ready */ - spin_unlock(&domain->lock); - - return ret; -} - - static void pdev_iommuv2_disable(struct pci_dev *pdev) { pci_disable_ats(pdev); @ drivers/iommu/amd_iommu.c:2032 @ static int attach_device(struct device *dev, struct pci_dev *pdev; struct iommu_dev_data *dev_data; unsigned long flags; - int ret; dev_data = get_dev_data(dev); @ drivers/iommu/amd_iommu.c:2058 @ static int attach_device(struct device *dev, } skip_ats_check: - write_lock_irqsave(&amd_iommu_devtable_lock, flags); - ret = __attach_device(dev_data, domain); - write_unlock_irqrestore(&amd_iommu_devtable_lock, flags); + + if (dev_data->domain != NULL) + return -EBUSY; + + spin_lock_irqsave(&domain->lock, flags); + __attach_device(dev_data, domain); + spin_unlock_irqrestore(&domain->lock, flags); /* * We might boot into a crash-kernel here. The crashed kernel @ drivers/iommu/amd_iommu.c:2073 @ static int attach_device(struct device *dev, */ domain_flush_tlb_pde(domain); - return ret; + return 0; } /* - * Removes a device from a protection domain (unlocked) - */ -static void __detach_device(struct iommu_dev_data *dev_data) -{ - struct protection_domain *domain; - - /* - * Must be called with IRQs disabled. Warn here to detect early - * when its not. - */ - WARN_ON(!irqs_disabled()); - - if (WARN_ON(!dev_data->domain)) - return; - - domain = dev_data->domain; - - spin_lock(&domain->lock); - - do_detach(dev_data); - - spin_unlock(&domain->lock); -} - -/* - * Removes a device from a protection domain (with devtable_lock held) + * Removes a device from a protection domain */ static void detach_device(struct device *dev) { @ drivers/iommu/amd_iommu.c:2088 @ static void detach_device(struct device *dev) dev_data = get_dev_data(dev); domain = dev_data->domain; - /* lock device table */ - write_lock_irqsave(&amd_iommu_devtable_lock, flags); + /* + * First check if the device is still attached. It might already + * be detached from its domain because the generic + * iommu_detach_group code detached it and we try again here in + * our alias handling. + */ + if (WARN_ON(!dev_data->domain)) + return; + + spin_lock_irqsave(&domain->lock, flags); __detach_device(dev_data); - write_unlock_irqrestore(&amd_iommu_devtable_lock, flags); + spin_unlock_irqrestore(&domain->lock, flags); if (!dev_is_pci(dev)) return; @ drivers/iommu/amd_iommu.c:2762 @ static void cleanup_domain(struct protection_domain *domain) struct iommu_dev_data *entry; unsigned long flags; - write_lock_irqsave(&amd_iommu_devtable_lock, flags); - + spin_lock_irqsave(&domain->lock, flags); while (!list_empty(&domain->dev_list)) { entry = list_first_entry(&domain->dev_list, struct iommu_dev_data, list); + BUG_ON(!entry->domain); __detach_device(entry); } - - write_unlock_irqrestore(&amd_iommu_devtable_lock, flags); + spin_unlock_irqrestore(&domain->lock, flags); } static void protection_domain_free(struct protection_domain *domain) @ drivers/iommu/amd_iommu.c:3521 @ EXPORT_SYMBOL(amd_iommu_device_info); *****************************************************************************/ static struct irq_chip amd_ir_chip; +static DEFINE_SPINLOCK(iommu_table_lock); static void set_dte_irq_entry(u16 devid, struct irq_remap_table *table) { @ drivers/iommu/amd_iommu.c:3537 @ static void set_dte_irq_entry(u16 devid, struct irq_remap_table *table) amd_iommu_dev_table[devid].data[2] = dte; } -static struct irq_remap_table *get_irq_table(u16 devid, bool ioapic) +static struct irq_remap_table *get_irq_table(u16 devid) +{ + struct irq_remap_table *table; + + if (WARN_ONCE(!amd_iommu_rlookup_table[devid], + "%s: no iommu for devid %x\n", __func__, devid)) + return NULL; + + table = irq_lookup_table[devid]; + if (WARN_ONCE(!table, "%s: no table for devid %x\n", __func__, devid)) + return NULL; + + return table; +} + +static struct irq_remap_table *__alloc_irq_table(void) +{ + struct irq_remap_table *table; + + table = kzalloc(sizeof(*table), GFP_KERNEL); + if (!table) + return NULL; + + table->table = kmem_cache_alloc(amd_iommu_irq_cache, GFP_KERNEL); + if (!table->table) { + kfree(table); + return NULL; + } + raw_spin_lock_init(&table->lock); + + if (!AMD_IOMMU_GUEST_IR_GA(amd_iommu_guest_ir)) + memset(table->table, 0, + MAX_IRQS_PER_TABLE * sizeof(u32)); + else + memset(table->table, 0, + (MAX_IRQS_PER_TABLE * (sizeof(u64) * 2))); + return table; +} + +static void set_remap_table_entry(struct amd_iommu *iommu, u16 devid, + struct irq_remap_table *table) +{ + irq_lookup_table[devid] = table; + set_dte_irq_entry(devid, table); + iommu_flush_dte(iommu, devid); +} + +static struct irq_remap_table *alloc_irq_table(u16 devid) { struct irq_remap_table *table = NULL; + struct irq_remap_table *new_table = NULL; struct amd_iommu *iommu; unsigned long flags; u16 alias; - write_lock_irqsave(&amd_iommu_devtable_lock, flags); + spin_lock_irqsave(&iommu_table_lock, flags); iommu = amd_iommu_rlookup_table[devid]; if (!iommu) @ drivers/iommu/amd_iommu.c:3605 @ static struct irq_remap_table *get_irq_table(u16 devid, bool ioapic) alias = amd_iommu_alias_table[devid]; table = irq_lookup_table[alias]; if (table) { - irq_lookup_table[devid] = table; - set_dte_irq_entry(devid, table); - iommu_flush_dte(iommu, devid); - goto out; + set_remap_table_entry(iommu, devid, table); + goto out_wait; } + spin_unlock_irqrestore(&iommu_table_lock, flags); /* Nothing there yet, allocate new irq remapping table */ - table = kzalloc(sizeof(*table), GFP_ATOMIC); - if (!table) + new_table = __alloc_irq_table(); + if (!new_table) + return NULL; + + spin_lock_irqsave(&iommu_table_lock, flags); + + table = irq_lookup_table[devid]; + if (table) goto out_unlock; - /* Initialize table spin-lock */ - spin_lock_init(&table->lock); - - if (ioapic) - /* Keep the first 32 indexes free for IOAPIC interrupts */ - table->min_index = 32; - - table->table = kmem_cache_alloc(amd_iommu_irq_cache, GFP_ATOMIC); - if (!table->table) { - kfree(table); - table = NULL; - goto out_unlock; + table = irq_lookup_table[alias]; + if (table) { + set_remap_table_entry(iommu, devid, table); + goto out_wait; } - if (!AMD_IOMMU_GUEST_IR_GA(amd_iommu_guest_ir)) - memset(table->table, 0, - MAX_IRQS_PER_TABLE * sizeof(u32)); - else - memset(table->table, 0, - (MAX_IRQS_PER_TABLE * (sizeof(u64) * 2))); + table = new_table; + new_table = NULL; - if (ioapic) { - int i; + set_remap_table_entry(iommu, devid, table); + if (devid != alias) + set_remap_table_entry(iommu, alias, table); - for (i = 0; i < 32; ++i) - iommu->irte_ops->set_allocated(table, i); - } - - irq_lookup_table[devid] = table; - set_dte_irq_entry(devid, table); - iommu_flush_dte(iommu, devid); - if (devid != alias) { - irq_lookup_table[alias] = table; - set_dte_irq_entry(alias, table); - iommu_flush_dte(iommu, alias); - } - -out: +out_wait: iommu_completion_wait(iommu); out_unlock: - write_unlock_irqrestore(&amd_iommu_devtable_lock, flags); + spin_unlock_irqrestore(&iommu_table_lock, flags); + if (new_table) { + kmem_cache_free(amd_iommu_irq_cache, new_table->table); + kfree(new_table); + } return table; } @ drivers/iommu/amd_iommu.c:3657 @ static int alloc_irq_index(u16 devid, int count, bool align) if (!iommu) return -ENODEV; - table = get_irq_table(devid, false); + table = alloc_irq_table(devid); if (!table) return -ENODEV; if (align) alignment = roundup_pow_of_two(count); - spin_lock_irqsave(&table->lock, flags); + raw_spin_lock_irqsave(&table->lock, flags); /* Scan table for free entries */ for (index = ALIGN(table->min_index, alignment), c = 0; @ drivers/iommu/amd_iommu.c:3691 @ static int alloc_irq_index(u16 devid, int count, bool align) index = -ENOSPC; out: - spin_unlock_irqrestore(&table->lock, flags); + raw_spin_unlock_irqrestore(&table->lock, flags); return index; } @ drivers/iommu/amd_iommu.c:3708 @ static int modify_irte_ga(u16 devid, int index, struct irte_ga *irte, if (iommu == NULL) return -EINVAL; - table = get_irq_table(devid, false); + table = get_irq_table(devid); if (!table) return -ENOMEM; - spin_lock_irqsave(&table->lock, flags); + raw_spin_lock_irqsave(&table->lock, flags); entry = (struct irte_ga *)table->table; entry = &entry[index]; @ drivers/iommu/amd_iommu.c:3723 @ static int modify_irte_ga(u16 devid, int index, struct irte_ga *irte, if (data) data->ref = entry; - spin_unlock_irqrestore(&table->lock, flags); + raw_spin_unlock_irqrestore(&table->lock, flags); iommu_flush_irt(iommu, devid); iommu_completion_wait(iommu); @ drivers/iommu/amd_iommu.c:3741 @ static int modify_irte(u16 devid, int index, union irte *irte) if (iommu == NULL) return -EINVAL; - table = get_irq_table(devid, false); + table = get_irq_table(devid); if (!table) return -ENOMEM; - spin_lock_irqsave(&table->lock, flags); + raw_spin_lock_irqsave(&table->lock, flags); table->table[index] = irte->val; - spin_unlock_irqrestore(&table->lock, flags); + raw_spin_unlock_irqrestore(&table->lock, flags); iommu_flush_irt(iommu, devid); iommu_completion_wait(iommu); @ drivers/iommu/amd_iommu.c:3765 @ static void free_irte(u16 devid, int index) if (iommu == NULL) return; - table = get_irq_table(devid, false); + table = get_irq_table(devid); if (!table) return; - spin_lock_irqsave(&table->lock, flags); + raw_spin_lock_irqsave(&table->lock, flags); iommu->irte_ops->clear_allocated(table, index); - spin_unlock_irqrestore(&table->lock, flags); + raw_spin_unlock_irqrestore(&table->lock, flags); iommu_flush_irt(iommu, devid); iommu_completion_wait(iommu); @ drivers/iommu/amd_iommu.c:3852 @ static void irte_ga_set_affinity(void *entry, u16 devid, u16 index, u8 vector, u32 dest_apicid) { struct irte_ga *irte = (struct irte_ga *) entry; - struct iommu_dev_data *dev_data = search_dev_data(devid); - if (!dev_data || !dev_data->use_vapic || - !irte->lo.fields_remap.guest_mode) { + if (!irte->lo.fields_remap.guest_mode) { irte->hi.fields.vector = vector; irte->lo.fields_remap.destination = dest_apicid; modify_irte_ga(devid, index, irte, NULL); @ drivers/iommu/amd_iommu.c:4059 @ static int irq_remapping_alloc(struct irq_domain *domain, unsigned int virq, struct amd_ir_data *data = NULL; struct irq_cfg *cfg; int i, ret, devid; - int index = -1; + int index; if (!info) return -EINVAL; @ drivers/iommu/amd_iommu.c:4083 @ static int irq_remapping_alloc(struct irq_domain *domain, unsigned int virq, return ret; if (info->type == X86_IRQ_ALLOC_TYPE_IOAPIC) { - if (get_irq_table(devid, true)) + struct irq_remap_table *table; + struct amd_iommu *iommu; + + table = alloc_irq_table(devid); + if (table) { + if (!table->min_index) { + /* + * Keep the first 32 indexes free for IOAPIC + * interrupts. + */ + table->min_index = 32; + iommu = amd_iommu_rlookup_table[devid]; + for (i = 0; i < 32; ++i) + iommu->irte_ops->set_allocated(table, i); + } + WARN_ON(table->min_index != 32); index = info->ioapic_pin; - else - ret = -ENOMEM; + } else { + index = -ENOMEM; + } } else { bool align = (info->type == X86_IRQ_ALLOC_TYPE_MSI); @ drivers/iommu/amd_iommu.c:4368 @ int amd_iommu_update_ga(int cpu, bool is_run, void *data) { unsigned long flags; struct amd_iommu *iommu; - struct irq_remap_table *irt; + struct irq_remap_table *table; struct amd_ir_data *ir_data = (struct amd_ir_data *)data; int devid = ir_data->irq_2_irte.devid; struct irte_ga *entry = (struct irte_ga *) ir_data->entry; @ drivers/iommu/amd_iommu.c:4382 @ int amd_iommu_update_ga(int cpu, bool is_run, void *data) if (!iommu) return -ENODEV; - irt = get_irq_table(devid, false); - if (!irt) + table = get_irq_table(devid); + if (!table) return -ENODEV; - spin_lock_irqsave(&irt->lock, flags); + raw_spin_lock_irqsave(&table->lock, flags); if (ref->lo.fields_vapic.guest_mode) { if (cpu >= 0) @ drivers/iommu/amd_iommu.c:4395 @ int amd_iommu_update_ga(int cpu, bool is_run, void *data) barrier(); } - spin_unlock_irqrestore(&irt->lock, flags); + raw_spin_unlock_irqrestore(&table->lock, flags); iommu_flush_irt(iommu, devid); iommu_completion_wait(iommu); @ drivers/iommu/amd_iommu_init.c:1477 @ static int __init init_iommu_one(struct amd_iommu *iommu, struct ivhd_header *h) { int ret; - spin_lock_init(&iommu->lock); + raw_spin_lock_init(&iommu->lock); /* Add IOMMU to internal data structures */ list_add_tail(&iommu->list, &amd_iommu_list); @ drivers/iommu/amd_iommu_types.h:411 @ extern bool amd_iommu_iotlb_sup; #define IRQ_TABLE_ALIGNMENT 128 struct irq_remap_table { - spinlock_t lock; + raw_spinlock_t lock; unsigned min_index; u32 *table; }; @ drivers/iommu/amd_iommu_types.h:493 @ struct amd_iommu { int index; /* locks the accesses to the hardware */ - spinlock_t lock; + raw_spinlock_t lock; /* Pointer to PCI device of this IOMMU */ struct pci_dev *dev; @ drivers/iommu/amd_iommu_types.h:630 @ struct devid_map { */ struct iommu_dev_data { struct list_head list; /* For domain->dev_list */ - struct list_head dev_data_list; /* For global dev_data_list */ + struct llist_node dev_data_list; /* For global dev_data_list */ struct protection_domain *domain; /* Domain the device is bound to */ u16 devid; /* PCI Device ID */ u16 alias; /* Alias Device ID */ @ drivers/leds/trigger/Kconfig:72 @ config LEDS_TRIGGER_BACKLIGHT config LEDS_TRIGGER_CPU bool "LED CPU Trigger" - depends on LEDS_TRIGGERS + depends on LEDS_TRIGGERS && !PREEMPT_RT_BASE help This allows LEDs to be controlled by active CPUs. This shows the active CPUs across an array of LEDs so you can see which @ drivers/md/bcache/Kconfig:4 @ config BCACHE tristate "Block device as cache" + depends on !PREEMPT_RT_FULL ---help--- Allows a block device to be used as cache for other devices; uses a btree for indexing and the layout is optimized for SSDs. @ drivers/md/dm-rq.c:691 @ static void dm_old_request_fn(struct request_queue *q) /* Establish tio->ti before queuing work (map_tio_request) */ tio->ti = ti; kthread_queue_work(&md->kworker, &tio->work); - BUG_ON(!irqs_disabled()); } } @ drivers/md/raid5.c:412 @ void raid5_release_stripe(struct stripe_head *sh) md_wakeup_thread(conf->mddev->thread); return; slow_path: - local_irq_save(flags); /* we are ok here if STRIPE_ON_RELEASE_LIST is set or not */ - if (atomic_dec_and_lock(&sh->count, &conf->device_lock)) { + if (atomic_dec_and_lock_irqsave(&sh->count, &conf->device_lock, flags)) { INIT_LIST_HEAD(&list); hash = sh->hash_lock_index; do_release_stripe(conf, sh, &list); - spin_unlock(&conf->device_lock); + spin_unlock_irqrestore(&conf->device_lock, flags); release_inactive_stripe_list(conf, &list, hash); } - local_irq_restore(flags); } static inline void remove_hash(struct stripe_head *sh) @ drivers/md/raid5.c:2067 @ static void raid_run_ops(struct stripe_head *sh, unsigned long ops_request) struct raid5_percpu *percpu; unsigned long cpu; - cpu = get_cpu(); + cpu = get_cpu_light(); percpu = per_cpu_ptr(conf->percpu, cpu); + spin_lock(&percpu->lock); if (test_bit(STRIPE_OP_BIOFILL, &ops_request)) { ops_run_biofill(sh); overlap_clear++; @ drivers/md/raid5.c:2128 @ static void raid_run_ops(struct stripe_head *sh, unsigned long ops_request) if (test_and_clear_bit(R5_Overlap, &dev->flags)) wake_up(&sh->raid_conf->wait_for_overlap); } - put_cpu(); + spin_unlock(&percpu->lock); + put_cpu_light(); } static void free_stripe(struct kmem_cache *sc, struct stripe_head *sh) @ drivers/md/raid5.c:6793 @ static int raid456_cpu_up_prepare(unsigned int cpu, struct hlist_node *node) __func__, cpu); return -ENOMEM; } + spin_lock_init(&per_cpu_ptr(conf->percpu, cpu)->lock); return 0; } @ drivers/md/raid5.c:6804 @ static int raid5_alloc_percpu(struct r5conf *conf) conf->percpu = alloc_percpu(struct raid5_percpu); if (!conf->percpu) return -ENOMEM; - err = cpuhp_state_add_instance(CPUHP_MD_RAID5_PREPARE, &conf->node); if (!err) { conf->scribble_disks = max(conf->raid_disks, @ drivers/md/raid5.h:639 @ struct r5conf { int recovery_disabled; /* per cpu variables */ struct raid5_percpu { + spinlock_t lock; /* Protection for -RT */ struct page *spare_page; /* Used when checking P/Q in raid6 */ struct flex_array *scribble; /* space for constructing buffer * lists and performing address @ drivers/mfd/atmel-smc.c:15 @ */ #include <linux/mfd/syscon/atmel-smc.h> +#include <linux/string.h> /** * atmel_smc_cs_conf_init - initialize a SMC CS conf @ drivers/misc/Kconfig:72 @ config ATMEL_TCB_CLKSRC are combined to make a single 32-bit timer. When GENERIC_CLOCKEVENTS is defined, the third timer channel - may be used as a clock event device supporting oneshot mode - (delays of up to two seconds) based on the 32 KiHz clock. + may be used as a clock event device supporting oneshot mode. config ATMEL_TCB_CLKSRC_BLOCK int @ drivers/misc/Kconfig:86 @ config ATMEL_TCB_CLKSRC_BLOCK TC can be used for other purposes, such as PWM generation and interval timing. +config ATMEL_TCB_CLKSRC_USE_SLOW_CLOCK + bool "TC Block use 32 KiHz clock" + depends on ATMEL_TCB_CLKSRC + default y + help + Select this to use 32 KiHz base clock rate as TC block clock + source for clock events. + + config DUMMY_IRQ tristate "Dummy IRQ handler" default n @ drivers/mmc/host/mmci.c:1256 @ static irqreturn_t mmci_pio_irq(int irq, void *dev_id) struct sg_mapping_iter *sg_miter = &host->sg_miter; struct variant_data *variant = host->variant; void __iomem *base = host->base; - unsigned long flags; u32 status; status = readl(base + MMCISTATUS); dev_dbg(mmc_dev(host->mmc), "irq1 (pio) %08x\n", status); - local_irq_save(flags); - do { unsigned int remain, len; char *buffer; @ drivers/mmc/host/mmci.c:1301 @ static irqreturn_t mmci_pio_irq(int irq, void *dev_id) sg_miter_stop(sg_miter); - local_irq_restore(flags); - /* * If we have less than the fifo 'half-full' threshold to transfer, * trigger a PIO interrupt as soon as any data is available. @ drivers/net/ethernet/3com/3c59x.c:768 @ static netdev_tx_t boomerang_start_xmit(struct sk_buff *skb, struct net_device *dev); static int vortex_rx(struct net_device *dev); static int boomerang_rx(struct net_device *dev); -static irqreturn_t vortex_interrupt(int irq, void *dev_id); -static irqreturn_t boomerang_interrupt(int irq, void *dev_id); +static irqreturn_t vortex_boomerang_interrupt(int irq, void *dev_id); +static irqreturn_t _vortex_interrupt(int irq, struct net_device *dev); +static irqreturn_t _boomerang_interrupt(int irq, struct net_device *dev); static int vortex_close(struct net_device *dev); static void dump_tx_ring(struct net_device *dev); static void update_stats(void __iomem *ioaddr, struct net_device *dev); @ drivers/net/ethernet/3com/3c59x.c:842 @ MODULE_PARM_DESC(use_mmio, "3c59x: use memory-mapped PCI I/O resource (0-1)"); #ifdef CONFIG_NET_POLL_CONTROLLER static void poll_vortex(struct net_device *dev) { - struct vortex_private *vp = netdev_priv(dev); - unsigned long flags; - local_irq_save(flags); - (vp->full_bus_master_rx ? boomerang_interrupt:vortex_interrupt)(dev->irq,dev); - local_irq_restore(flags); + vortex_boomerang_interrupt(dev->irq, dev); } #endif @ drivers/net/ethernet/3com/3c59x.c:1728 @ vortex_open(struct net_device *dev) dma_addr_t dma; /* Use the now-standard shared IRQ implementation. */ - if ((retval = request_irq(dev->irq, vp->full_bus_master_rx ? - boomerang_interrupt : vortex_interrupt, IRQF_SHARED, dev->name, dev))) { + if ((retval = request_irq(dev->irq, vortex_boomerang_interrupt, IRQF_SHARED, dev->name, dev))) { pr_err("%s: Could not reserve IRQ %d\n", dev->name, dev->irq); goto err; } @ drivers/net/ethernet/3com/3c59x.c:1903 @ static void vortex_tx_timeout(struct net_device *dev) pr_err("%s: Interrupt posted but not delivered --" " IRQ blocked by another device?\n", dev->name); /* Bad idea here.. but we might as well handle a few events. */ - { - /* - * Block interrupts because vortex_interrupt does a bare spin_lock() - */ - unsigned long flags; - local_irq_save(flags); - if (vp->full_bus_master_tx) - boomerang_interrupt(dev->irq, dev); - else - vortex_interrupt(dev->irq, dev); - local_irq_restore(flags); - } + vortex_boomerang_interrupt(dev->irq, dev); } if (vortex_debug > 0) @ drivers/net/ethernet/3com/3c59x.c:2254 @ boomerang_start_xmit(struct sk_buff *skb, struct net_device *dev) */ static irqreturn_t -vortex_interrupt(int irq, void *dev_id) +_vortex_interrupt(int irq, struct net_device *dev) { - struct net_device *dev = dev_id; struct vortex_private *vp = netdev_priv(dev); void __iomem *ioaddr; int status; @ drivers/net/ethernet/3com/3c59x.c:2264 @ vortex_interrupt(int irq, void *dev_id) unsigned int bytes_compl = 0, pkts_compl = 0; ioaddr = vp->ioaddr; - spin_lock(&vp->lock); status = ioread16(ioaddr + EL3_STATUS); @ drivers/net/ethernet/3com/3c59x.c:2361 @ vortex_interrupt(int irq, void *dev_id) pr_debug("%s: exiting interrupt, status %4.4x.\n", dev->name, status); handler_exit: - spin_unlock(&vp->lock); return IRQ_RETVAL(handled); } @ drivers/net/ethernet/3com/3c59x.c:2370 @ vortex_interrupt(int irq, void *dev_id) */ static irqreturn_t -boomerang_interrupt(int irq, void *dev_id) +_boomerang_interrupt(int irq, struct net_device *dev) { - struct net_device *dev = dev_id; struct vortex_private *vp = netdev_priv(dev); void __iomem *ioaddr; int status; @ drivers/net/ethernet/3com/3c59x.c:2381 @ boomerang_interrupt(int irq, void *dev_id) ioaddr = vp->ioaddr; - - /* - * It seems dopey to put the spinlock this early, but we could race against vortex_tx_timeout - * and boomerang_start_xmit - */ - spin_lock(&vp->lock); vp->handling_irq = 1; status = ioread16(ioaddr + EL3_STATUS); @ drivers/net/ethernet/3com/3c59x.c:2499 @ boomerang_interrupt(int irq, void *dev_id) dev->name, status); handler_exit: vp->handling_irq = 0; - spin_unlock(&vp->lock); return IRQ_RETVAL(handled); } +static irqreturn_t +vortex_boomerang_interrupt(int irq, void *dev_id) +{ + struct net_device *dev = dev_id; + struct vortex_private *vp = netdev_priv(dev); + unsigned long flags; + irqreturn_t ret; + + spin_lock_irqsave(&vp->lock, flags); + + if (vp->full_bus_master_rx) + ret = _boomerang_interrupt(dev->irq, dev); + else + ret = _vortex_interrupt(dev->irq, dev); + + spin_unlock_irqrestore(&vp->lock, flags); + + return ret; +} + static int vortex_rx(struct net_device *dev) { struct vortex_private *vp = netdev_priv(dev); @ drivers/net/wireless/intersil/orinoco/orinoco_usb.c:700 @ static void ezusb_req_ctx_wait(struct ezusb_priv *upriv, while (!ctx->done.done && msecs--) udelay(1000); } else { - wait_event_interruptible(ctx->done.wait, + swait_event_interruptible(ctx->done.wait, ctx->done.done); } break; @ drivers/oprofile/oprofilefs.c:141 @ static int __oprofilefs_create_file(struct dentry *root, char const *name, struct dentry *dentry; struct inode *inode; + if (!root) + return -ENOMEM; + inode_lock(d_inode(root)); dentry = d_alloc_name(root, name); if (!dentry) { @ drivers/pci/switch/switchtec.c:44 @ struct switchtec_user { enum mrpc_state state; - struct completion comp; + wait_queue_head_t cmd_comp; struct kref kref; struct list_head list; + bool cmd_done; u32 cmd; u32 status; u32 return_code; @ drivers/pci/switch/switchtec.c:70 @ static struct switchtec_user *stuser_create(struct switchtec_dev *stdev) stuser->stdev = stdev; kref_init(&stuser->kref); INIT_LIST_HEAD(&stuser->list); - init_completion(&stuser->comp); + init_waitqueue_head(&stuser->cmd_comp); stuser->event_cnt = atomic_read(&stdev->event_cnt); dev_dbg(&stdev->dev, "%s: %p\n", __func__, stuser); @ drivers/pci/switch/switchtec.c:153 @ static int mrpc_queue_cmd(struct switchtec_user *stuser) kref_get(&stuser->kref); stuser->read_len = sizeof(stuser->data); stuser_set_state(stuser, MRPC_QUEUED); - init_completion(&stuser->comp); + stuser->cmd_done = false; list_add_tail(&stuser->list, &stdev->mrpc_queue); mrpc_cmd_submit(stdev); @ drivers/pci/switch/switchtec.c:190 @ static void mrpc_complete_cmd(struct switchtec_dev *stdev) stuser->read_len); out: - complete_all(&stuser->comp); + stuser->cmd_done = true; + wake_up_interruptible(&stuser->cmd_comp); list_del_init(&stuser->list); stuser_put(stuser); stdev->mrpc_busy = 0; @ drivers/pci/switch/switchtec.c:461 @ static ssize_t switchtec_dev_read(struct file *filp, char __user *data, mutex_unlock(&stdev->mrpc_mutex); if (filp->f_flags & O_NONBLOCK) { - if (!try_wait_for_completion(&stuser->comp)) + if (!READ_ONCE(stuser->cmd_done)) return -EAGAIN; } else { - rc = wait_for_completion_interruptible(&stuser->comp); + rc = wait_event_interruptible(stuser->cmd_comp, + stuser->cmd_done); if (rc < 0) return rc; } @ drivers/pci/switch/switchtec.c:513 @ static __poll_t switchtec_dev_poll(struct file *filp, poll_table *wait) struct switchtec_dev *stdev = stuser->stdev; __poll_t ret = 0; - poll_wait(filp, &stuser->comp.wait, wait); + poll_wait(filp, &stuser->cmd_comp, wait); poll_wait(filp, &stdev->event_wq, wait); if (lock_mutex_and_test_alive(stdev)) @ drivers/pci/switch/switchtec.c:521 @ static __poll_t switchtec_dev_poll(struct file *filp, poll_table *wait) mutex_unlock(&stdev->mrpc_mutex); - if (try_wait_for_completion(&stuser->comp)) + if (READ_ONCE(stuser->cmd_done)) ret |= EPOLLIN | EPOLLRDNORM; if (stuser->event_cnt != atomic_read(&stdev->event_cnt)) @ drivers/pci/switch/switchtec.c:1040 @ static void stdev_kill(struct switchtec_dev *stdev) /* Wake up and kill any users waiting on an MRPC request */ list_for_each_entry_safe(stuser, tmpuser, &stdev->mrpc_queue, list) { - complete_all(&stuser->comp); + stuser->cmd_done = true; + wake_up_interruptible(&stuser->cmd_comp); list_del_init(&stuser->list); stuser_put(stuser); } @ drivers/scsi/fcoe/fcoe.c:1462 @ static int fcoe_rcv(struct sk_buff *skb, struct net_device *netdev, static int fcoe_alloc_paged_crc_eof(struct sk_buff *skb, int tlen) { struct fcoe_percpu_s *fps; - int rc; + int rc, cpu = get_cpu_light(); - fps = &get_cpu_var(fcoe_percpu); + fps = &per_cpu(fcoe_percpu, cpu); rc = fcoe_get_paged_crc_eof(skb, tlen, fps); - put_cpu_var(fcoe_percpu); + put_cpu_light(); return rc; } @ drivers/scsi/fcoe/fcoe.c:1653 @ static inline int fcoe_filter_frames(struct fc_lport *lport, return 0; } - stats = per_cpu_ptr(lport->stats, get_cpu()); + stats = per_cpu_ptr(lport->stats, get_cpu_light()); stats->InvalidCRCCount++; if (stats->InvalidCRCCount < 5) printk(KERN_WARNING "fcoe: dropping frame with CRC error\n"); - put_cpu(); + put_cpu_light(); return -EINVAL; } @ drivers/scsi/fcoe/fcoe.c:1700 @ static void fcoe_recv_frame(struct sk_buff *skb) */ hp = (struct fcoe_hdr *) skb_network_header(skb); - stats = per_cpu_ptr(lport->stats, get_cpu()); + stats = per_cpu_ptr(lport->stats, get_cpu_light()); if (unlikely(FC_FCOE_DECAPS_VER(hp) != FC_FCOE_VER)) { if (stats->ErrorFrames < 5) printk(KERN_WARNING "fcoe: FCoE version " @ drivers/scsi/fcoe/fcoe.c:1732 @ static void fcoe_recv_frame(struct sk_buff *skb) goto drop; if (!fcoe_filter_frames(lport, fp)) { - put_cpu(); + put_cpu_light(); fc_exch_recv(lport, fp); return; } drop: stats->ErrorFrames++; - put_cpu(); + put_cpu_light(); kfree_skb(skb); } @ drivers/scsi/fcoe/fcoe_ctlr.c:838 @ static unsigned long fcoe_ctlr_age_fcfs(struct fcoe_ctlr *fip) INIT_LIST_HEAD(&del_list); - stats = per_cpu_ptr(fip->lp->stats, get_cpu()); + stats = per_cpu_ptr(fip->lp->stats, get_cpu_light()); list_for_each_entry_safe(fcf, next, &fip->fcfs, list) { deadline = fcf->time + fcf->fka_period + fcf->fka_period / 2; @ drivers/scsi/fcoe/fcoe_ctlr.c:874 @ static unsigned long fcoe_ctlr_age_fcfs(struct fcoe_ctlr *fip) sel_time = fcf->time; } } - put_cpu(); + put_cpu_light(); list_for_each_entry_safe(fcf, next, &del_list, list) { /* Removes fcf from current list */ @ drivers/scsi/libfc/fc_exch.c:836 @ static struct fc_exch *fc_exch_em_alloc(struct fc_lport *lport, } memset(ep, 0, sizeof(*ep)); - cpu = get_cpu(); + cpu = get_cpu_light(); pool = per_cpu_ptr(mp->pool, cpu); spin_lock_bh(&pool->lock); - put_cpu(); + put_cpu_light(); /* peek cache of free slot */ if (pool->left != FC_XID_UNKNOWN) { @ drivers/scsi/libsas/sas_ata.c:179 @ static void sas_ata_task_done(struct sas_task *task) static unsigned int sas_ata_qc_issue(struct ata_queued_cmd *qc) { - unsigned long flags; struct sas_task *task; struct scatterlist *sg; int ret = AC_ERR_SYSTEM; @ drivers/scsi/libsas/sas_ata.c:192 @ static unsigned int sas_ata_qc_issue(struct ata_queued_cmd *qc) /* TODO: audit callers to ensure they are ready for qc_issue to * unconditionally re-enable interrupts */ - local_irq_save(flags); spin_unlock(ap->lock); /* If the device fell off, no sense in issuing commands */ @ drivers/scsi/libsas/sas_ata.c:253 @ static unsigned int sas_ata_qc_issue(struct ata_queued_cmd *qc) out: spin_lock(ap->lock); - local_irq_restore(flags); return ret; } @ drivers/scsi/qla2xxx/qla_inline.h:60 @ qla2x00_debounce_register(volatile uint16_t __iomem *addr) static inline void qla2x00_poll(struct rsp_que *rsp) { - unsigned long flags; struct qla_hw_data *ha = rsp->hw; - local_irq_save(flags); + if (IS_P3P_TYPE(ha)) qla82xx_poll(0, rsp); else ha->isp_ops->intr_handler(0, rsp); - local_irq_restore(flags); } static inline uint8_t * @ drivers/staging/lustre/lustre/llite/dcache.c:93 @ static int ll_dcompare(const struct dentry *dentry, d_count(dentry)); /* mountpoint is always valid */ - if (d_mountpoint((struct dentry *)dentry)) + if (d_mountpoint(dentry)) return 0; if (d_lustre_invalid(dentry)) @ drivers/staging/lustre/lustre/llite/dcache.c:114 @ static int ll_ddelete(const struct dentry *de) LASSERT(de); CDEBUG(D_DENTRY, "%s dentry %pd (%p, parent %p, inode %p) %s%s\n", - d_lustre_invalid((struct dentry *)de) ? "deleting" : "keeping", + d_lustre_invalid(de) ? "deleting" : "keeping", de, de, de->d_parent, d_inode(de), d_unhashed(de) ? "" : "hashed,", list_empty(&de->d_subdirs) ? "" : "subdirs"); @ drivers/staging/lustre/lustre/llite/dcache.c:122 @ static int ll_ddelete(const struct dentry *de) /* kernel >= 2.6.38 last refcount is decreased after this function. */ LASSERT(d_count(de) == 1); - if (d_lustre_invalid((struct dentry *)de)) + if (d_lustre_invalid(de)) return 1; return 0; } @ drivers/thermal/x86_pkg_temp_thermal.c:32 @ #include <linux/pm.h> #include <linux/thermal.h> #include <linux/debugfs.h> +#include <linux/swork.h> #include <asm/cpu_device_id.h> #include <asm/mce.h> @ drivers/thermal/x86_pkg_temp_thermal.c:333 @ static void pkg_thermal_schedule_work(int cpu, struct delayed_work *work) schedule_delayed_work_on(cpu, work, ms); } -static int pkg_thermal_notify(u64 msr_val) +static void pkg_thermal_notify_work(struct swork_event *event) { int cpu = smp_processor_id(); struct pkg_device *pkgdev; @ drivers/thermal/x86_pkg_temp_thermal.c:352 @ static int pkg_thermal_notify(u64 msr_val) } spin_unlock_irqrestore(&pkg_temp_lock, flags); +} + +#ifdef CONFIG_PREEMPT_RT_FULL +static struct swork_event notify_work; + +static int pkg_thermal_notify_work_init(void) +{ + int err; + + err = swork_get(); + if (err) + return err; + + INIT_SWORK(¬ify_work, pkg_thermal_notify_work); return 0; } +static void pkg_thermal_notify_work_cleanup(void) +{ + swork_put(); +} + +static int pkg_thermal_notify(u64 msr_val) +{ + swork_queue(¬ify_work); + return 0; +} + +#else /* !CONFIG_PREEMPT_RT_FULL */ + +static int pkg_thermal_notify_work_init(void) { return 0; } + +static void pkg_thermal_notify_work_cleanup(void) { } + +static int pkg_thermal_notify(u64 msr_val) +{ + pkg_thermal_notify_work(NULL); + return 0; +} +#endif /* CONFIG_PREEMPT_RT_FULL */ + static int pkg_temp_thermal_device_add(unsigned int cpu) { int pkgid = topology_logical_package_id(cpu); @ drivers/thermal/x86_pkg_temp_thermal.c:557 @ static int __init pkg_temp_thermal_init(void) if (!x86_match_cpu(pkg_temp_thermal_ids)) return -ENODEV; + if (!pkg_thermal_notify_work_init()) + return -ENODEV; + max_packages = topology_max_packages(); packages = kzalloc(max_packages * sizeof(struct pkg_device *), GFP_KERNEL); - if (!packages) - return -ENOMEM; + if (!packages) { + ret = -ENOMEM; + goto err; + } ret = cpuhp_setup_state(CPUHP_AP_ONLINE_DYN, "thermal/x86_pkg:online", pkg_thermal_cpu_online, pkg_thermal_cpu_offline); @ drivers/thermal/x86_pkg_temp_thermal.c:583 @ static int __init pkg_temp_thermal_init(void) return 0; err: + pkg_thermal_notify_work_cleanup(); kfree(packages); return ret; } @ drivers/thermal/x86_pkg_temp_thermal.c:597 @ static void __exit pkg_temp_thermal_exit(void) cpuhp_remove_state(pkg_thermal_hp_state); debugfs_remove_recursive(debugfs); kfree(packages); + pkg_thermal_notify_work_cleanup(); } module_exit(pkg_temp_thermal_exit) @ drivers/tty/serial/8250/8250_core.c:57 @ static struct uart_driver serial8250_reg; static unsigned int skip_txen_test; /* force skip of txen test at init time */ -#define PASS_LIMIT 512 +/* + * On -rt we can have a more delays, and legitimately + * so - so don't drop work spuriously and spam the + * syslog: + */ +#ifdef CONFIG_PREEMPT_RT_FULL +# define PASS_LIMIT 1000000 +#else +# define PASS_LIMIT 512 +#endif #include <asm/serial.h> /* @ drivers/tty/serial/8250/8250_port.c:34 @ #include <linux/nmi.h> #include <linux/mutex.h> #include <linux/slab.h> +#include <linux/kdb.h> #include <linux/uaccess.h> #include <linux/pm_runtime.h> #include <linux/ktime.h> @ drivers/tty/serial/8250/8250_port.c:3222 @ void serial8250_console_write(struct uart_8250_port *up, const char *s, serial8250_rpm_get(up); - if (port->sysrq) + if (port->sysrq || oops_in_progress) locked = 0; - else if (oops_in_progress) + else if (in_kdb_printk()) locked = spin_trylock_irqsave(&port->lock, flags); else spin_lock_irqsave(&port->lock, flags); @ drivers/tty/serial/amba-pl011.c:2203 @ pl011_console_write(struct console *co, const char *s, unsigned int count) clk_enable(uap->clk); - local_irq_save(flags); + /* + * local_irq_save(flags); + * + * This local_irq_save() is nonsense. If we come in via sysrq + * handling then interrupts are already disabled. Aside of + * that the port.sysrq check is racy on SMP regardless. + */ if (uap->port.sysrq) locked = 0; else if (oops_in_progress) - locked = spin_trylock(&uap->port.lock); + locked = spin_trylock_irqsave(&uap->port.lock, flags); else - spin_lock(&uap->port.lock); + spin_lock_irqsave(&uap->port.lock, flags); /* * First save the CR then disable the interrupts @ drivers/tty/serial/amba-pl011.c:2241 @ pl011_console_write(struct console *co, const char *s, unsigned int count) pl011_write(old_cr, uap, REG_CR); if (locked) - spin_unlock(&uap->port.lock); - local_irq_restore(flags); + spin_unlock_irqrestore(&uap->port.lock, flags); clk_disable(uap->clk); } @ drivers/tty/serial/atmel_serial.c:1760 @ static int atmel_startup(struct uart_port *port) { struct platform_device *pdev = to_platform_device(port->dev); struct atmel_uart_port *atmel_port = to_atmel_uart_port(port); - struct tty_struct *tty = port->state->port.tty; int retval; /* @ drivers/tty/serial/atmel_serial.c:1774 @ static int atmel_startup(struct uart_port *port) * Allocate the IRQ */ retval = request_irq(port->irq, atmel_interrupt, - IRQF_SHARED | IRQF_COND_SUSPEND, - tty ? tty->name : "atmel_serial", port); + IRQF_SHARED | IRQF_COND_SUSPEND, port->name, port); if (retval) { dev_err(port->dev, "atmel_startup - Can't get irq\n"); return retval; @ drivers/tty/serial/omap-serial.c:1310 @ serial_omap_console_write(struct console *co, const char *s, pm_runtime_get_sync(up->dev); - local_irq_save(flags); - if (up->port.sysrq) - locked = 0; - else if (oops_in_progress) - locked = spin_trylock(&up->port.lock); + if (up->port.sysrq || oops_in_progress) + locked = spin_trylock_irqsave(&up->port.lock, flags); else - spin_lock(&up->port.lock); + spin_lock_irqsave(&up->port.lock, flags); /* * First save the IER then disable the interrupts @ drivers/tty/serial/omap-serial.c:1342 @ serial_omap_console_write(struct console *co, const char *s, pm_runtime_mark_last_busy(up->dev); pm_runtime_put_autosuspend(up->dev); if (locked) - spin_unlock(&up->port.lock); - local_irq_restore(flags); + spin_unlock_irqrestore(&up->port.lock, flags); } static int __init @ drivers/usb/core/hcd.c:1739 @ static void __usb_hcd_giveback_urb(struct urb *urb) struct usb_hcd *hcd = bus_to_hcd(urb->dev->bus); struct usb_anchor *anchor = urb->anchor; int status = urb->unlinked; - unsigned long flags; urb->hcpriv = NULL; if (unlikely((urb->transfer_flags & URB_SHORT_NOT_OK) && @ drivers/usb/core/hcd.c:1766 @ static void __usb_hcd_giveback_urb(struct urb *urb) * and no one may trigger the above deadlock situation when * running complete() in tasklet. */ - local_irq_save(flags); urb->complete(urb); - local_irq_restore(flags); usb_anchor_resume_wakeups(anchor); atomic_dec(&urb->use_count); @ drivers/usb/gadget/function/f_fs.c:1615 @ static void ffs_data_put(struct ffs_data *ffs) pr_info("%s(): freeing\n", __func__); ffs_data_clear(ffs); BUG_ON(waitqueue_active(&ffs->ev.waitq) || - waitqueue_active(&ffs->ep0req_completion.wait) || + swait_active(&ffs->ep0req_completion.wait) || waitqueue_active(&ffs->wait)); destroy_workqueue(ffs->io_completion_wq); kfree(ffs->dev_name); @ drivers/usb/gadget/legacy/inode.c:346 @ ep_io (struct ep_data *epdata, void *buf, unsigned len) spin_unlock_irq (&epdata->dev->lock); if (likely (value == 0)) { - value = wait_event_interruptible (done.wait, done.done); + value = swait_event_interruptible (done.wait, done.done); if (value != 0) { spin_lock_irq (&epdata->dev->lock); if (likely (epdata->ep != NULL)) { @ drivers/usb/gadget/legacy/inode.c:355 @ ep_io (struct ep_data *epdata, void *buf, unsigned len) usb_ep_dequeue (epdata->ep, epdata->req); spin_unlock_irq (&epdata->dev->lock); - wait_event (done.wait, done.done); + swait_event (done.wait, done.done); if (epdata->status == -ECONNRESET) epdata->status = -EINTR; } else { @ fs/Makefile:14 @ obj-y := open.o read_write.o file_table.o super.o \ ioctl.o readdir.o select.o dcache.o inode.o \ attr.o bad_inode.o file.o filesystems.o namespace.o \ seq_file.o xattr.o libfs.o fs-writeback.o \ - pnode.o splice.o sync.o utimes.o \ + pnode.o splice.o sync.o utimes.o d_path.o \ stack.o fs_struct.o statfs.o fs_pin.o nsfs.o ifeq ($(CONFIG_BLOCK),y) @ fs/aio.c:43 @ #include <linux/ramfs.h> #include <linux/percpu-refcount.h> #include <linux/mount.h> +#include <linux/swork.h> #include <asm/kmap_types.h> #include <linux/uaccess.h> @ fs/aio.c:121 @ struct kioctx { struct rcu_head free_rcu; struct work_struct free_work; /* see free_ioctx() */ + struct swork_event free_swork; /* see free_ioctx() */ /* * signals when all in-flight requests are done @ fs/aio.c:264 @ static int __init aio_setup(void) .mount = aio_mount, .kill_sb = kill_anon_super, }; + BUG_ON(swork_get()); aio_mnt = kern_mount(&aio_fs); if (IS_ERR(aio_mnt)) panic("Failed to create aio fs mount."); @ fs/aio.c:639 @ static void free_ioctx_reqs(struct percpu_ref *ref) * and ctx->users has dropped to 0, so we know no more kiocbs can be submitted - * now it's safe to cancel any that need to be. */ -static void free_ioctx_users(struct percpu_ref *ref) +static void free_ioctx_users_work(struct swork_event *sev) { - struct kioctx *ctx = container_of(ref, struct kioctx, users); + struct kioctx *ctx = container_of(sev, struct kioctx, free_swork); struct aio_kiocb *req; spin_lock_irq(&ctx->ctx_lock); @ fs/aio.c:659 @ static void free_ioctx_users(struct percpu_ref *ref) percpu_ref_put(&ctx->reqs); } +static void free_ioctx_users(struct percpu_ref *ref) +{ + struct kioctx *ctx = container_of(ref, struct kioctx, users); + + INIT_SWORK(&ctx->free_swork, free_ioctx_users_work); + swork_queue(&ctx->free_swork); +} + static int ioctx_add_table(struct kioctx *ctx, struct mm_struct *mm) { unsigned i, new_nr; @ fs/autofs4/autofs_i.h:23 @ #include <linux/sched.h> #include <linux/mount.h> #include <linux/namei.h> +#include <linux/delay.h> #include <linux/uaccess.h> #include <linux/mutex.h> #include <linux/spinlock.h> @ fs/autofs4/expire.c:151 @ static struct dentry *get_next_positive_dentry(struct dentry *prev, parent = p->d_parent; if (!spin_trylock(&parent->d_lock)) { spin_unlock(&p->d_lock); - cpu_relax(); + cpu_chill(); goto relock; } spin_unlock(&p->d_lock); @ fs/buffer.c:277 @ static void end_buffer_async_read(struct buffer_head *bh, int uptodate) * decide that the page is now completely done. */ first = page_buffers(page); - local_irq_save(flags); - bit_spin_lock(BH_Uptodate_Lock, &first->b_state); + flags = bh_uptodate_lock_irqsave(first); clear_buffer_async_read(bh); unlock_buffer(bh); tmp = bh; @ fs/buffer.c:290 @ static void end_buffer_async_read(struct buffer_head *bh, int uptodate) } tmp = tmp->b_this_page; } while (tmp != bh); - bit_spin_unlock(BH_Uptodate_Lock, &first->b_state); - local_irq_restore(flags); + bh_uptodate_unlock_irqrestore(first, flags); /* * If none of the buffers had errors and they are all @ fs/buffer.c:302 @ static void end_buffer_async_read(struct buffer_head *bh, int uptodate) return; still_busy: - bit_spin_unlock(BH_Uptodate_Lock, &first->b_state); - local_irq_restore(flags); - return; + bh_uptodate_unlock_irqrestore(first, flags); } /* @ fs/buffer.c:329 @ void end_buffer_async_write(struct buffer_head *bh, int uptodate) } first = page_buffers(page); - local_irq_save(flags); - bit_spin_lock(BH_Uptodate_Lock, &first->b_state); + flags = bh_uptodate_lock_irqsave(first); clear_buffer_async_write(bh); unlock_buffer(bh); @ fs/buffer.c:341 @ void end_buffer_async_write(struct buffer_head *bh, int uptodate) } tmp = tmp->b_this_page; } - bit_spin_unlock(BH_Uptodate_Lock, &first->b_state); - local_irq_restore(flags); + bh_uptodate_unlock_irqrestore(first, flags); end_page_writeback(page); return; still_busy: - bit_spin_unlock(BH_Uptodate_Lock, &first->b_state); - local_irq_restore(flags); - return; + bh_uptodate_unlock_irqrestore(first, flags); } EXPORT_SYMBOL(end_buffer_async_write); @ fs/buffer.c:3367 @ struct buffer_head *alloc_buffer_head(gfp_t gfp_flags) struct buffer_head *ret = kmem_cache_zalloc(bh_cachep, gfp_flags); if (ret) { INIT_LIST_HEAD(&ret->b_assoc_buffers); + buffer_head_init_locks(ret); preempt_disable(); __this_cpu_inc(bh_accounting.nr); recalc_bh_state(); @ fs/cifs/readdir.c:83 @ cifs_prime_dcache(struct dentry *parent, struct qstr *name, struct inode *inode; struct super_block *sb = parent->d_sb; struct cifs_sb_info *cifs_sb = CIFS_SB(sb); - DECLARE_WAIT_QUEUE_HEAD_ONSTACK(wq); + DECLARE_SWAIT_QUEUE_HEAD_ONSTACK(wq); cifs_dbg(FYI, "%s: for %s\n", __func__, name->name); @ fs/d_path.c:4 @ +/* SPDX-License-Identifier: GPL-2.0 */ +#include <linux/syscalls.h> +#include <linux/export.h> +#include <linux/uaccess.h> +#include <linux/fs_struct.h> +#include <linux/fs.h> +#include <linux/slab.h> +#include <linux/prefetch.h> +#include "mount.h" + +static int prepend(char **buffer, int *buflen, const char *str, int namelen) +{ + *buflen -= namelen; + if (*buflen < 0) + return -ENAMETOOLONG; + *buffer -= namelen; + memcpy(*buffer, str, namelen); + return 0; +} + +/** + * prepend_name - prepend a pathname in front of current buffer pointer + * @buffer: buffer pointer + * @buflen: allocated length of the buffer + * @name: name string and length qstr structure + * + * With RCU path tracing, it may race with d_move(). Use READ_ONCE() to + * make sure that either the old or the new name pointer and length are + * fetched. However, there may be mismatch between length and pointer. + * The length cannot be trusted, we need to copy it byte-by-byte until + * the length is reached or a null byte is found. It also prepends "/" at + * the beginning of the name. The sequence number check at the caller will + * retry it again when a d_move() does happen. So any garbage in the buffer + * due to mismatched pointer and length will be discarded. + * + * Load acquire is needed to make sure that we see that terminating NUL. + */ +static int prepend_name(char **buffer, int *buflen, const struct qstr *name) +{ + const char *dname = smp_load_acquire(&name->name); /* ^^^ */ + u32 dlen = READ_ONCE(name->len); + char *p; + + *buflen -= dlen + 1; + if (*buflen < 0) + return -ENAMETOOLONG; + p = *buffer -= dlen + 1; + *p++ = '/'; + while (dlen--) { + char c = *dname++; + if (!c) + break; + *p++ = c; + } + return 0; +} + +/** + * prepend_path - Prepend path string to a buffer + * @path: the dentry/vfsmount to report + * @root: root vfsmnt/dentry + * @buffer: pointer to the end of the buffer + * @buflen: pointer to buffer length + * + * The function will first try to write out the pathname without taking any + * lock other than the RCU read lock to make sure that dentries won't go away. + * It only checks the sequence number of the global rename_lock as any change + * in the dentry's d_seq will be preceded by changes in the rename_lock + * sequence number. If the sequence number had been changed, it will restart + * the whole pathname back-tracing sequence again by taking the rename_lock. + * In this case, there is no need to take the RCU read lock as the recursive + * parent pointer references will keep the dentry chain alive as long as no + * rename operation is performed. + */ +static int prepend_path(const struct path *path, + const struct path *root, + char **buffer, int *buflen) +{ + struct dentry *dentry; + struct vfsmount *vfsmnt; + struct mount *mnt; + int error = 0; + unsigned seq, m_seq = 0; + char *bptr; + int blen; + + rcu_read_lock(); +restart_mnt: + read_seqbegin_or_lock(&mount_lock, &m_seq); + seq = 0; + rcu_read_lock(); +restart: + bptr = *buffer; + blen = *buflen; + error = 0; + dentry = path->dentry; + vfsmnt = path->mnt; + mnt = real_mount(vfsmnt); + read_seqbegin_or_lock(&rename_lock, &seq); + while (dentry != root->dentry || vfsmnt != root->mnt) { + struct dentry * parent; + + if (dentry == vfsmnt->mnt_root || IS_ROOT(dentry)) { + struct mount *parent = READ_ONCE(mnt->mnt_parent); + /* Escaped? */ + if (dentry != vfsmnt->mnt_root) { + bptr = *buffer; + blen = *buflen; + error = 3; + break; + } + /* Global root? */ + if (mnt != parent) { + dentry = READ_ONCE(mnt->mnt_mountpoint); + mnt = parent; + vfsmnt = &mnt->mnt; + continue; + } + if (!error) + error = is_mounted(vfsmnt) ? 1 : 2; + break; + } + parent = dentry->d_parent; + prefetch(parent); + error = prepend_name(&bptr, &blen, &dentry->d_name); + if (error) + break; + + dentry = parent; + } + if (!(seq & 1)) + rcu_read_unlock(); + if (need_seqretry(&rename_lock, seq)) { + seq = 1; + goto restart; + } + done_seqretry(&rename_lock, seq); + + if (!(m_seq & 1)) + rcu_read_unlock(); + if (need_seqretry(&mount_lock, m_seq)) { + m_seq = 1; + goto restart_mnt; + } + done_seqretry(&mount_lock, m_seq); + + if (error >= 0 && bptr == *buffer) { + if (--blen < 0) + error = -ENAMETOOLONG; + else + *--bptr = '/'; + } + *buffer = bptr; + *buflen = blen; + return error; +} + +/** + * __d_path - return the path of a dentry + * @path: the dentry/vfsmount to report + * @root: root vfsmnt/dentry + * @buf: buffer to return value in + * @buflen: buffer length + * + * Convert a dentry into an ASCII path name. + * + * Returns a pointer into the buffer or an error code if the + * path was too long. + * + * "buflen" should be positive. + * + * If the path is not reachable from the supplied root, return %NULL. + */ +char *__d_path(const struct path *path, + const struct path *root, + char *buf, int buflen) +{ + char *res = buf + buflen; + int error; + + prepend(&res, &buflen, "\0", 1); + error = prepend_path(path, root, &res, &buflen); + + if (error < 0) + return ERR_PTR(error); + if (error > 0) + return NULL; + return res; +} + +char *d_absolute_path(const struct path *path, + char *buf, int buflen) +{ + struct path root = {}; + char *res = buf + buflen; + int error; + + prepend(&res, &buflen, "\0", 1); + error = prepend_path(path, &root, &res, &buflen); + + if (error > 1) + error = -EINVAL; + if (error < 0) + return ERR_PTR(error); + return res; +} + +/* + * same as __d_path but appends "(deleted)" for unlinked files. + */ +static int path_with_deleted(const struct path *path, + const struct path *root, + char **buf, int *buflen) +{ + prepend(buf, buflen, "\0", 1); + if (d_unlinked(path->dentry)) { + int error = prepend(buf, buflen, " (deleted)", 10); + if (error) + return error; + } + + return prepend_path(path, root, buf, buflen); +} + +static int prepend_unreachable(char **buffer, int *buflen) +{ + return prepend(buffer, buflen, "(unreachable)", 13); +} + +static void get_fs_root_rcu(struct fs_struct *fs, struct path *root) +{ + unsigned seq; + + do { + seq = read_seqcount_begin(&fs->seq); + *root = fs->root; + } while (read_seqcount_retry(&fs->seq, seq)); +} + +/** + * d_path - return the path of a dentry + * @path: path to report + * @buf: buffer to return value in + * @buflen: buffer length + * + * Convert a dentry into an ASCII path name. If the entry has been deleted + * the string " (deleted)" is appended. Note that this is ambiguous. + * + * Returns a pointer into the buffer or an error code if the path was + * too long. Note: Callers should use the returned pointer, not the passed + * in buffer, to use the name! The implementation often starts at an offset + * into the buffer, and may leave 0 bytes at the start. + * + * "buflen" should be positive. + */ +char *d_path(const struct path *path, char *buf, int buflen) +{ + char *res = buf + buflen; + struct path root; + int error; + + /* + * We have various synthetic filesystems that never get mounted. On + * these filesystems dentries are never used for lookup purposes, and + * thus don't need to be hashed. They also don't need a name until a + * user wants to identify the object in /proc/pid/fd/. The little hack + * below allows us to generate a name for these objects on demand: + * + * Some pseudo inodes are mountable. When they are mounted + * path->dentry == path->mnt->mnt_root. In that case don't call d_dname + * and instead have d_path return the mounted path. + */ + if (path->dentry->d_op && path->dentry->d_op->d_dname && + (!IS_ROOT(path->dentry) || path->dentry != path->mnt->mnt_root)) + return path->dentry->d_op->d_dname(path->dentry, buf, buflen); + + rcu_read_lock(); + get_fs_root_rcu(current->fs, &root); + error = path_with_deleted(path, &root, &res, &buflen); + rcu_read_unlock(); + + if (error < 0) + res = ERR_PTR(error); + return res; +} +EXPORT_SYMBOL(d_path); + +/* + * Helper function for dentry_operations.d_dname() members + */ +char *dynamic_dname(struct dentry *dentry, char *buffer, int buflen, + const char *fmt, ...) +{ + va_list args; + char temp[64]; + int sz; + + va_start(args, fmt); + sz = vsnprintf(temp, sizeof(temp), fmt, args) + 1; + va_end(args); + + if (sz > sizeof(temp) || sz > buflen) + return ERR_PTR(-ENAMETOOLONG); + + buffer += buflen - sz; + return memcpy(buffer, temp, sz); +} + +char *simple_dname(struct dentry *dentry, char *buffer, int buflen) +{ + char *end = buffer + buflen; + /* these dentries are never renamed, so d_lock is not needed */ + if (prepend(&end, &buflen, " (deleted)", 11) || + prepend(&end, &buflen, dentry->d_name.name, dentry->d_name.len) || + prepend(&end, &buflen, "/", 1)) + end = ERR_PTR(-ENAMETOOLONG); + return end; +} +EXPORT_SYMBOL(simple_dname); + +/* + * Write full pathname from the root of the filesystem into the buffer. + */ +static char *__dentry_path(struct dentry *d, char *buf, int buflen) +{ + struct dentry *dentry; + char *end, *retval; + int len, seq = 0; + int error = 0; + + if (buflen < 2) + goto Elong; + + rcu_read_lock(); +restart: + dentry = d; + end = buf + buflen; + len = buflen; + prepend(&end, &len, "\0", 1); + /* Get '/' right */ + retval = end-1; + *retval = '/'; + read_seqbegin_or_lock(&rename_lock, &seq); + while (!IS_ROOT(dentry)) { + struct dentry *parent = dentry->d_parent; + + prefetch(parent); + error = prepend_name(&end, &len, &dentry->d_name); + if (error) + break; + + retval = end; + dentry = parent; + } + if (!(seq & 1)) + rcu_read_unlock(); + if (need_seqretry(&rename_lock, seq)) { + seq = 1; + goto restart; + } + done_seqretry(&rename_lock, seq); + if (error) + goto Elong; + return retval; +Elong: + return ERR_PTR(-ENAMETOOLONG); +} + +char *dentry_path_raw(struct dentry *dentry, char *buf, int buflen) +{ + return __dentry_path(dentry, buf, buflen); +} +EXPORT_SYMBOL(dentry_path_raw); + +char *dentry_path(struct dentry *dentry, char *buf, int buflen) +{ + char *p = NULL; + char *retval; + + if (d_unlinked(dentry)) { + p = buf + buflen; + if (prepend(&p, &buflen, "//deleted", 10) != 0) + goto Elong; + buflen++; + } + retval = __dentry_path(dentry, buf, buflen); + if (!IS_ERR(retval) && p) + *p = '/'; /* restore '/' overriden with '\0' */ + return retval; +Elong: + return ERR_PTR(-ENAMETOOLONG); +} + +static void get_fs_root_and_pwd_rcu(struct fs_struct *fs, struct path *root, + struct path *pwd) +{ + unsigned seq; + + do { + seq = read_seqcount_begin(&fs->seq); + *root = fs->root; + *pwd = fs->pwd; + } while (read_seqcount_retry(&fs->seq, seq)); +} + +/* + * NOTE! The user-level library version returns a + * character pointer. The kernel system call just + * returns the length of the buffer filled (which + * includes the ending '\0' character), or a negative + * error value. So libc would do something like + * + * char *getcwd(char * buf, size_t size) + * { + * int retval; + * + * retval = sys_getcwd(buf, size); + * if (retval >= 0) + * return buf; + * errno = -retval; + * return NULL; + * } + */ +SYSCALL_DEFINE2(getcwd, char __user *, buf, unsigned long, size) +{ + int error; + struct path pwd, root; + char *page = __getname(); + + if (!page) + return -ENOMEM; + + rcu_read_lock(); + get_fs_root_and_pwd_rcu(current->fs, &root, &pwd); + + error = -ENOENT; + if (!d_unlinked(pwd.dentry)) { + unsigned long len; + char *cwd = page + PATH_MAX; + int buflen = PATH_MAX; + + prepend(&cwd, &buflen, "\0", 1); + error = prepend_path(&pwd, &root, &cwd, &buflen); + rcu_read_unlock(); + + if (error < 0) + goto out; + + /* Unreachable from current root */ + if (error > 0) { + error = prepend_unreachable(&cwd, &buflen); + if (error) + goto out; + } + + error = -ERANGE; + len = PATH_MAX + page - cwd; + if (len <= size) { + error = len; + if (copy_to_user(buf, cwd, len)) + error = -EFAULT; + } + } else { + rcu_read_unlock(); + } + +out: + __putname(page); + return error; +} @ fs/dcache.c:17 @ * the dcache entry is deleted or garbage collected. */ -#include <linux/syscalls.h> +#include <linux/ratelimit.h> #include <linux/string.h> #include <linux/mm.h> #include <linux/fs.h> @ fs/dcache.c:27 @ #include <linux/hash.h> #include <linux/cache.h> #include <linux/export.h> -#include <linux/mount.h> -#include <linux/file.h> -#include <linux/uaccess.h> #include <linux/security.h> #include <linux/seqlock.h> -#include <linux/swap.h> #include <linux/bootmem.h> -#include <linux/fs_struct.h> #include <linux/bit_spinlock.h> #include <linux/rculist_bl.h> -#include <linux/prefetch.h> -#include <linux/ratelimit.h> #include <linux/list_lru.h> #include "internal.h" #include "mount.h" @ fs/dcache.c:70 @ * dentry->d_lock * * If no ancestor relationship: - * if (dentry1 < dentry2) - * dentry1->d_lock - * dentry2->d_lock + * arbitrary, since it's serialized on rename_lock */ int sysctl_vfs_cache_pressure __read_mostly = 100; EXPORT_SYMBOL_GPL(sysctl_vfs_cache_pressure); @ fs/dcache.c:434 @ static void d_lru_shrink_move(struct list_lru_one *lru, struct dentry *dentry, list_lru_isolate_move(lru, &dentry->d_lru, list); } -/* - * dentry_lru_(add|del)_list) must be called with d_lock held. - */ -static void dentry_lru_add(struct dentry *dentry) -{ - if (unlikely(!(dentry->d_flags & DCACHE_LRU_LIST))) - d_lru_add(dentry); - else if (unlikely(!(dentry->d_flags & DCACHE_REFERENCED))) - dentry->d_flags |= DCACHE_REFERENCED; -} - /** * d_drop - drop a dentry * @dentry: dentry to drop @ fs/dcache.c:453 @ static void dentry_lru_add(struct dentry *dentry) */ static void ___d_drop(struct dentry *dentry) { - if (!d_unhashed(dentry)) { - struct hlist_bl_head *b; - /* - * Hashed dentries are normally on the dentry hashtable, - * with the exception of those newly allocated by - * d_obtain_root, which are always IS_ROOT: - */ - if (unlikely(IS_ROOT(dentry))) - b = &dentry->d_sb->s_roots; - else - b = d_hash(dentry->d_name.hash); + struct hlist_bl_head *b; + /* + * Hashed dentries are normally on the dentry hashtable, + * with the exception of those newly allocated by + * d_obtain_root, which are always IS_ROOT: + */ + if (unlikely(IS_ROOT(dentry))) + b = &dentry->d_sb->s_roots; + else + b = d_hash(dentry->d_name.hash); - hlist_bl_lock(b); - __hlist_bl_del(&dentry->d_hash); - hlist_bl_unlock(b); - /* After this call, in-progress rcu-walk path lookup will fail. */ - write_seqcount_invalidate(&dentry->d_seq); - } + hlist_bl_lock(b); + __hlist_bl_del(&dentry->d_hash); + hlist_bl_unlock(b); } void __d_drop(struct dentry *dentry) { - ___d_drop(dentry); - dentry->d_hash.pprev = NULL; + if (!d_unhashed(dentry)) { + ___d_drop(dentry); + dentry->d_hash.pprev = NULL; + write_seqcount_invalidate(&dentry->d_seq); + } } EXPORT_SYMBOL(__d_drop); @ fs/dcache.c:571 @ static void __dentry_kill(struct dentry *dentry) dentry_free(dentry); } -/* - * Finish off a dentry we've decided to kill. - * dentry->d_lock must be held, returns with it unlocked. - * If ref is non-zero, then decrement the refcount too. - * Returns dentry requiring refcount drop, or NULL if we're done. - */ -static struct dentry *dentry_kill(struct dentry *dentry) - __releases(dentry->d_lock) +static struct dentry *__lock_parent(struct dentry *dentry) { - struct inode *inode = dentry->d_inode; - struct dentry *parent = NULL; - - if (inode && unlikely(!spin_trylock(&inode->i_lock))) - goto failed; - - if (!IS_ROOT(dentry)) { - parent = dentry->d_parent; - if (unlikely(!spin_trylock(&parent->d_lock))) { - if (inode) - spin_unlock(&inode->i_lock); - goto failed; - } - } - - __dentry_kill(dentry); - return parent; - -failed: - spin_unlock(&dentry->d_lock); - return dentry; /* try again with same dentry */ -} - -static inline struct dentry *lock_parent(struct dentry *dentry) -{ - struct dentry *parent = dentry->d_parent; - if (IS_ROOT(dentry)) - return NULL; - if (unlikely(dentry->d_lockref.count < 0)) - return NULL; - if (likely(spin_trylock(&parent->d_lock))) - return parent; + struct dentry *parent; rcu_read_lock(); spin_unlock(&dentry->d_lock); again: @ fs/dcache.c:591 @ static inline struct dentry *lock_parent(struct dentry *dentry) spin_unlock(&parent->d_lock); goto again; } - if (parent != dentry) { - spin_lock_nested(&dentry->d_lock, DENTRY_D_LOCK_NESTED); - if (unlikely(dentry->d_lockref.count < 0)) { - spin_unlock(&parent->d_lock); - parent = NULL; - } - } else { - parent = NULL; - } rcu_read_unlock(); + if (parent != dentry) + spin_lock_nested(&dentry->d_lock, DENTRY_D_LOCK_NESTED); + else + parent = NULL; return parent; } +static inline struct dentry *lock_parent(struct dentry *dentry) +{ + struct dentry *parent = dentry->d_parent; + if (IS_ROOT(dentry)) + return NULL; + if (likely(spin_trylock(&parent->d_lock))) + return parent; + return __lock_parent(dentry); +} + +static inline bool retain_dentry(struct dentry *dentry) +{ + WARN_ON(d_in_lookup(dentry)); + + /* Unreachable? Get rid of it */ + if (unlikely(d_unhashed(dentry))) + return false; + + if (unlikely(dentry->d_flags & DCACHE_DISCONNECTED)) + return false; + + if (unlikely(dentry->d_flags & DCACHE_OP_DELETE)) { + if (dentry->d_op->d_delete(dentry)) + return false; + } + /* retain; LRU fodder */ + dentry->d_lockref.count--; + if (unlikely(!(dentry->d_flags & DCACHE_LRU_LIST))) + d_lru_add(dentry); + else if (unlikely(!(dentry->d_flags & DCACHE_REFERENCED))) + dentry->d_flags |= DCACHE_REFERENCED; + return true; +} + +/* + * Finish off a dentry we've decided to kill. + * dentry->d_lock must be held, returns with it unlocked. + * Returns dentry requiring refcount drop, or NULL if we're done. + */ +static struct dentry *dentry_kill(struct dentry *dentry) + __releases(dentry->d_lock) +{ + struct inode *inode = dentry->d_inode; + struct dentry *parent = NULL; + + if (inode && unlikely(!spin_trylock(&inode->i_lock))) + goto slow_positive; + + if (!IS_ROOT(dentry)) { + parent = dentry->d_parent; + if (unlikely(!spin_trylock(&parent->d_lock))) { + parent = __lock_parent(dentry); + if (likely(inode || !dentry->d_inode)) + goto got_locks; + /* negative that became positive */ + if (parent) + spin_unlock(&parent->d_lock); + inode = dentry->d_inode; + goto slow_positive; + } + } + __dentry_kill(dentry); + return parent; + +slow_positive: + spin_unlock(&dentry->d_lock); + spin_lock(&inode->i_lock); + spin_lock(&dentry->d_lock); + parent = lock_parent(dentry); +got_locks: + if (unlikely(dentry->d_lockref.count != 1)) { + dentry->d_lockref.count--; + } else if (likely(!retain_dentry(dentry))) { + __dentry_kill(dentry); + return parent; + } + /* we are keeping it, after all */ + if (inode) + spin_unlock(&inode->i_lock); + if (parent) + spin_unlock(&parent->d_lock); + spin_unlock(&dentry->d_lock); + return NULL; +} + /* * Try to do a lockless dput(), and return whether that was successful. * @ fs/dcache.c:831 @ void dput(struct dentry *dentry) /* Slow case: now with the dentry lock held */ rcu_read_unlock(); - WARN_ON(d_in_lookup(dentry)); - - /* Unreachable? Get rid of it */ - if (unlikely(d_unhashed(dentry))) - goto kill_it; - - if (unlikely(dentry->d_flags & DCACHE_DISCONNECTED)) - goto kill_it; - - if (unlikely(dentry->d_flags & DCACHE_OP_DELETE)) { - if (dentry->d_op->d_delete(dentry)) - goto kill_it; + if (likely(retain_dentry(dentry))) { + spin_unlock(&dentry->d_lock); + return; } - dentry_lru_add(dentry); - - dentry->d_lockref.count--; - spin_unlock(&dentry->d_lock); - return; - -kill_it: dentry = dentry_kill(dentry); if (dentry) { cond_resched(); @ fs/dcache.c:984 @ void d_prune_aliases(struct inode *inode) } EXPORT_SYMBOL(d_prune_aliases); +/* + * Lock a dentry from shrink list. + * Called under rcu_read_lock() and dentry->d_lock; the former + * guarantees that nothing we access will be freed under us. + * Note that dentry is *not* protected from concurrent dentry_kill(), + * d_delete(), etc. + * + * Return false if dentry has been disrupted or grabbed, leaving + * the caller to kick it off-list. Otherwise, return true and have + * that dentry's inode and parent both locked. + */ +static bool shrink_lock_dentry(struct dentry *dentry) +{ + struct inode *inode; + struct dentry *parent; + + if (dentry->d_lockref.count) + return false; + + inode = dentry->d_inode; + if (inode && unlikely(!spin_trylock(&inode->i_lock))) { + spin_unlock(&dentry->d_lock); + spin_lock(&inode->i_lock); + spin_lock(&dentry->d_lock); + if (unlikely(dentry->d_lockref.count)) + goto out; + /* changed inode means that somebody had grabbed it */ + if (unlikely(inode != dentry->d_inode)) + goto out; + } + + parent = dentry->d_parent; + if (IS_ROOT(dentry) || likely(spin_trylock(&parent->d_lock))) + return true; + + spin_unlock(&dentry->d_lock); + spin_lock(&parent->d_lock); + if (unlikely(parent != dentry->d_parent)) { + spin_unlock(&parent->d_lock); + spin_lock(&dentry->d_lock); + goto out; + } + spin_lock_nested(&dentry->d_lock, DENTRY_D_LOCK_NESTED); + if (likely(!dentry->d_lockref.count)) + return true; + spin_unlock(&parent->d_lock); +out: + if (inode) + spin_unlock(&inode->i_lock); + return false; +} + static void shrink_dentry_list(struct list_head *list) { - struct dentry *dentry, *parent; - while (!list_empty(list)) { - struct inode *inode; + struct dentry *dentry, *parent; + dentry = list_entry(list->prev, struct dentry, d_lru); spin_lock(&dentry->d_lock); - parent = lock_parent(dentry); - - /* - * The dispose list is isolated and dentries are not accounted - * to the LRU here, so we can simply remove it from the list - * here regardless of whether it is referenced or not. - */ - d_shrink_del(dentry); - - /* - * We found an inuse dentry which was not removed from - * the LRU because of laziness during lookup. Do not free it. - */ - if (dentry->d_lockref.count > 0) { + rcu_read_lock(); + if (!shrink_lock_dentry(dentry)) { + bool can_free = false; + rcu_read_unlock(); + d_shrink_del(dentry); + if (dentry->d_lockref.count < 0) + can_free = dentry->d_flags & DCACHE_MAY_FREE; spin_unlock(&dentry->d_lock); - if (parent) - spin_unlock(&parent->d_lock); - continue; - } - - - if (unlikely(dentry->d_flags & DCACHE_DENTRY_KILLED)) { - bool can_free = dentry->d_flags & DCACHE_MAY_FREE; - spin_unlock(&dentry->d_lock); - if (parent) - spin_unlock(&parent->d_lock); if (can_free) dentry_free(dentry); continue; } - - inode = dentry->d_inode; - if (inode && unlikely(!spin_trylock(&inode->i_lock))) { - d_shrink_add(dentry, list); - spin_unlock(&dentry->d_lock); - if (parent) - spin_unlock(&parent->d_lock); - continue; - } - + rcu_read_unlock(); + d_shrink_del(dentry); + parent = dentry->d_parent; __dentry_kill(dentry); - + if (parent == dentry) + continue; /* * We need to prune ancestors too. This is necessary to prevent * quadratic behavior of shrink_dcache_parent(), but is also @ fs/dcache.c:1068 @ static void shrink_dentry_list(struct list_head *list) * fragmentation. */ dentry = parent; - while (dentry && !lockref_put_or_lock(&dentry->d_lockref)) { - parent = lock_parent(dentry); - if (dentry->d_lockref.count != 1) { - dentry->d_lockref.count--; - spin_unlock(&dentry->d_lock); - if (parent) - spin_unlock(&parent->d_lock); - break; - } - inode = dentry->d_inode; /* can't be NULL */ - if (unlikely(!spin_trylock(&inode->i_lock))) { - spin_unlock(&dentry->d_lock); - if (parent) - spin_unlock(&parent->d_lock); - cpu_relax(); - continue; - } - __dentry_kill(dentry); - dentry = parent; - } + while (dentry && !lockref_put_or_lock(&dentry->d_lockref)) + dentry = dentry_kill(dentry); } } @ fs/dcache.c:2418 @ EXPORT_SYMBOL(d_hash_and_lookup); void d_delete(struct dentry * dentry) { - struct inode *inode; - int isdir = 0; + struct inode *inode = dentry->d_inode; + int isdir = d_is_dir(dentry); + + spin_lock(&inode->i_lock); + spin_lock(&dentry->d_lock); /* * Are we the only user? */ -again: - spin_lock(&dentry->d_lock); - inode = dentry->d_inode; - isdir = S_ISDIR(inode->i_mode); if (dentry->d_lockref.count == 1) { - if (!spin_trylock(&inode->i_lock)) { - spin_unlock(&dentry->d_lock); - cpu_relax(); - goto again; - } dentry->d_flags &= ~DCACHE_CANT_MOUNT; dentry_unlink_inode(dentry); - fsnotify_nameremove(dentry, isdir); - return; - } - - if (!d_unhashed(dentry)) + } else { __d_drop(dentry); - - spin_unlock(&dentry->d_lock); - + spin_unlock(&dentry->d_lock); + spin_unlock(&inode->i_lock); + } fsnotify_nameremove(dentry, isdir); } EXPORT_SYMBOL(d_delete); @ fs/dcache.c:2465 @ EXPORT_SYMBOL(d_rehash); static inline unsigned start_dir_add(struct inode *dir) { + preempt_disable_rt(); for (;;) { - unsigned n = dir->i_dir_seq; - if (!(n & 1) && cmpxchg(&dir->i_dir_seq, n, n + 1) == n) + unsigned n = dir->__i_dir_seq; + if (!(n & 1) && cmpxchg(&dir->__i_dir_seq, n, n + 1) == n) return n; cpu_relax(); } @ fs/dcache.c:2476 @ static inline unsigned start_dir_add(struct inode *dir) static inline void end_dir_add(struct inode *dir, unsigned n) { - smp_store_release(&dir->i_dir_seq, n + 2); + smp_store_release(&dir->__i_dir_seq, n + 2); + preempt_enable_rt(); } static void d_wait_lookup(struct dentry *dentry) { - if (d_in_lookup(dentry)) { - DECLARE_WAITQUEUE(wait, current); - add_wait_queue(dentry->d_wait, &wait); - do { - set_current_state(TASK_UNINTERRUPTIBLE); - spin_unlock(&dentry->d_lock); - schedule(); - spin_lock(&dentry->d_lock); - } while (d_in_lookup(dentry)); - } + struct swait_queue __wait; + + if (!d_in_lookup(dentry)) + return; + + INIT_LIST_HEAD(&__wait.task_list); + do { + prepare_to_swait(dentry->d_wait, &__wait, TASK_UNINTERRUPTIBLE); + spin_unlock(&dentry->d_lock); + schedule(); + spin_lock(&dentry->d_lock); + } while (d_in_lookup(dentry)); + finish_swait(dentry->d_wait, &__wait); } struct dentry *d_alloc_parallel(struct dentry *parent, const struct qstr *name, - wait_queue_head_t *wq) + struct swait_queue_head *wq) { unsigned int hash = name->hash; struct hlist_bl_head *b = in_lookup_hash(parent, hash); @ fs/dcache.c:2513 @ struct dentry *d_alloc_parallel(struct dentry *parent, retry: rcu_read_lock(); - seq = smp_load_acquire(&parent->d_inode->i_dir_seq); + seq = smp_load_acquire(&parent->d_inode->__i_dir_seq); r_seq = read_seqbegin(&rename_lock); dentry = __d_lookup_rcu(parent, name, &d_seq); if (unlikely(dentry)) { @ fs/dcache.c:2541 @ struct dentry *d_alloc_parallel(struct dentry *parent, } hlist_bl_lock(b); - if (unlikely(READ_ONCE(parent->d_inode->i_dir_seq) != seq)) { + if (unlikely(READ_ONCE(parent->d_inode->__i_dir_seq) != seq)) { hlist_bl_unlock(b); rcu_read_unlock(); goto retry; @ fs/dcache.c:2614 @ void __d_lookup_done(struct dentry *dentry) hlist_bl_lock(b); dentry->d_flags &= ~DCACHE_PAR_LOOKUP; __hlist_bl_del(&dentry->d_u.d_in_lookup_hash); - wake_up_all(dentry->d_wait); + swake_up_all(dentry->d_wait); dentry->d_wait = NULL; hlist_bl_unlock(b); INIT_HLIST_NODE(&dentry->d_u.d_alias); @ fs/dcache.c:2803 @ static void copy_name(struct dentry *dentry, struct dentry *target) kfree_rcu(old_name, u.head); } -static void dentry_lock_for_move(struct dentry *dentry, struct dentry *target) -{ - /* - * XXXX: do we really need to take target->d_lock? - */ - if (IS_ROOT(dentry) || dentry->d_parent == target->d_parent) - spin_lock(&target->d_parent->d_lock); - else { - if (d_ancestor(dentry->d_parent, target->d_parent)) { - spin_lock(&dentry->d_parent->d_lock); - spin_lock_nested(&target->d_parent->d_lock, - DENTRY_D_LOCK_NESTED); - } else { - spin_lock(&target->d_parent->d_lock); - spin_lock_nested(&dentry->d_parent->d_lock, - DENTRY_D_LOCK_NESTED); - } - } - if (target < dentry) { - spin_lock_nested(&target->d_lock, 2); - spin_lock_nested(&dentry->d_lock, 3); - } else { - spin_lock_nested(&dentry->d_lock, 2); - spin_lock_nested(&target->d_lock, 3); - } -} - -static void dentry_unlock_for_move(struct dentry *dentry, struct dentry *target) -{ - if (target->d_parent != dentry->d_parent) - spin_unlock(&dentry->d_parent->d_lock); - if (target->d_parent != target) - spin_unlock(&target->d_parent->d_lock); - spin_unlock(&target->d_lock); - spin_unlock(&dentry->d_lock); -} - -/* - * When switching names, the actual string doesn't strictly have to - * be preserved in the target - because we're dropping the target - * anyway. As such, we can just do a simple memcpy() to copy over - * the new name before we switch, unless we are going to rehash - * it. Note that if we *do* unhash the target, we are not allowed - * to rehash it without giving it a new name/hash key - whether - * we swap or overwrite the names here, resulting name won't match - * the reality in filesystem; it's only there for d_path() purposes. - * Note that all of this is happening under rename_lock, so the - * any hash lookup seeing it in the middle of manipulations will - * be discarded anyway. So we do not care what happens to the hash - * key in that case. - */ /* * __d_move - move a dentry * @dentry: entry to move @ fs/dcache.c:2817 @ static void dentry_unlock_for_move(struct dentry *dentry, struct dentry *target) static void __d_move(struct dentry *dentry, struct dentry *target, bool exchange) { + struct dentry *old_parent, *p; struct inode *dir = NULL; unsigned n; - if (!dentry->d_inode) - printk(KERN_WARNING "VFS: moving negative dcache entry\n"); - BUG_ON(d_ancestor(dentry, target)); + WARN_ON(!dentry->d_inode); + if (WARN_ON(dentry == target)) + return; + BUG_ON(d_ancestor(target, dentry)); + old_parent = dentry->d_parent; + p = d_ancestor(old_parent, target); + if (IS_ROOT(dentry)) { + BUG_ON(p); + spin_lock(&target->d_parent->d_lock); + } else if (!p) { + /* target is not a descendent of dentry->d_parent */ + spin_lock(&target->d_parent->d_lock); + spin_lock_nested(&old_parent->d_lock, DENTRY_D_LOCK_NESTED); + } else { + BUG_ON(p == dentry); + spin_lock(&old_parent->d_lock); + if (p != target) + spin_lock_nested(&target->d_parent->d_lock, + DENTRY_D_LOCK_NESTED); + } + spin_lock_nested(&dentry->d_lock, 2); + spin_lock_nested(&target->d_lock, 3); - dentry_lock_for_move(dentry, target); if (unlikely(d_in_lookup(target))) { dir = target->d_parent->d_inode; n = start_dir_add(dir); @ fs/dcache.c:2855 @ static void __d_move(struct dentry *dentry, struct dentry *target, write_seqcount_begin_nested(&target->d_seq, DENTRY_D_LOCK_NESTED); /* unhash both */ - /* ___d_drop does write_seqcount_barrier, but they're OK to nest. */ - ___d_drop(dentry); - ___d_drop(target); - - /* Switch the names.. */ - if (exchange) - swap_names(dentry, target); - else - copy_name(dentry, target); - - /* rehash in new place(s) */ - __d_rehash(dentry); - if (exchange) - __d_rehash(target); - else - target->d_hash.pprev = NULL; + if (!d_unhashed(dentry)) + ___d_drop(dentry); + if (!d_unhashed(target)) + ___d_drop(target); /* ... and switch them in the tree */ - if (IS_ROOT(dentry)) { - /* splicing a tree */ - dentry->d_flags |= DCACHE_RCUACCESS; - dentry->d_parent = target->d_parent; - target->d_parent = target; - list_del_init(&target->d_child); - list_move(&dentry->d_child, &dentry->d_parent->d_subdirs); + dentry->d_parent = target->d_parent; + if (!exchange) { + copy_name(dentry, target); + target->d_hash.pprev = NULL; + dentry->d_parent->d_lockref.count++; + if (dentry == old_parent) + dentry->d_flags |= DCACHE_RCUACCESS; + else + WARN_ON(!--old_parent->d_lockref.count); } else { - /* swapping two dentries */ - swap(dentry->d_parent, target->d_parent); + target->d_parent = old_parent; + swap_names(dentry, target); list_move(&target->d_child, &target->d_parent->d_subdirs); - list_move(&dentry->d_child, &dentry->d_parent->d_subdirs); - if (exchange) - fsnotify_update_flags(target); - fsnotify_update_flags(dentry); + __d_rehash(target); + fsnotify_update_flags(target); } + list_move(&dentry->d_child, &dentry->d_parent->d_subdirs); + __d_rehash(dentry); + fsnotify_update_flags(dentry); write_seqcount_end(&target->d_seq); write_seqcount_end(&dentry->d_seq); if (dir) end_dir_add(dir, n); - dentry_unlock_for_move(dentry, target); + + if (dentry->d_parent != old_parent) + spin_unlock(&dentry->d_parent->d_lock); + if (dentry != old_parent) + spin_unlock(&old_parent->d_lock); + spin_unlock(&target->d_lock); + spin_unlock(&dentry->d_lock); } /* @ fs/dcache.c:3040 @ struct dentry *d_splice_alias(struct inode *inode, struct dentry *dentry) inode->i_sb->s_type->name, inode->i_sb->s_id); } else if (!IS_ROOT(new)) { + struct dentry *old_parent = dget(new->d_parent); int err = __d_unalias(inode, dentry, new); write_sequnlock(&rename_lock); if (err) { dput(new); new = ERR_PTR(err); } + dput(old_parent); } else { __d_move(new, dentry, false); write_sequnlock(&rename_lock); @ fs/dcache.c:3062 @ struct dentry *d_splice_alias(struct inode *inode, struct dentry *dentry) } EXPORT_SYMBOL(d_splice_alias); -static int prepend(char **buffer, int *buflen, const char *str, int namelen) -{ - *buflen -= namelen; - if (*buflen < 0) - return -ENAMETOOLONG; - *buffer -= namelen; - memcpy(*buffer, str, namelen); - return 0; -} - -/** - * prepend_name - prepend a pathname in front of current buffer pointer - * @buffer: buffer pointer - * @buflen: allocated length of the buffer - * @name: name string and length qstr structure - * - * With RCU path tracing, it may race with d_move(). Use READ_ONCE() to - * make sure that either the old or the new name pointer and length are - * fetched. However, there may be mismatch between length and pointer. - * The length cannot be trusted, we need to copy it byte-by-byte until - * the length is reached or a null byte is found. It also prepends "/" at - * the beginning of the name. The sequence number check at the caller will - * retry it again when a d_move() does happen. So any garbage in the buffer - * due to mismatched pointer and length will be discarded. - * - * Load acquire is needed to make sure that we see that terminating NUL. - */ -static int prepend_name(char **buffer, int *buflen, const struct qstr *name) -{ - const char *dname = smp_load_acquire(&name->name); /* ^^^ */ - u32 dlen = READ_ONCE(name->len); - char *p; - - *buflen -= dlen + 1; - if (*buflen < 0) - return -ENAMETOOLONG; - p = *buffer -= dlen + 1; - *p++ = '/'; - while (dlen--) { - char c = *dname++; - if (!c) - break; - *p++ = c; - } - return 0; -} - -/** - * prepend_path - Prepend path string to a buffer - * @path: the dentry/vfsmount to report - * @root: root vfsmnt/dentry - * @buffer: pointer to the end of the buffer - * @buflen: pointer to buffer length - * - * The function will first try to write out the pathname without taking any - * lock other than the RCU read lock to make sure that dentries won't go away. - * It only checks the sequence number of the global rename_lock as any change - * in the dentry's d_seq will be preceded by changes in the rename_lock - * sequence number. If the sequence number had been changed, it will restart - * the whole pathname back-tracing sequence again by taking the rename_lock. - * In this case, there is no need to take the RCU read lock as the recursive - * parent pointer references will keep the dentry chain alive as long as no - * rename operation is performed. - */ -static int prepend_path(const struct path *path, - const struct path *root, - char **buffer, int *buflen) -{ - struct dentry *dentry; - struct vfsmount *vfsmnt; - struct mount *mnt; - int error = 0; - unsigned seq, m_seq = 0; - char *bptr; - int blen; - - rcu_read_lock(); -restart_mnt: - read_seqbegin_or_lock(&mount_lock, &m_seq); - seq = 0; - rcu_read_lock(); -restart: - bptr = *buffer; - blen = *buflen; - error = 0; - dentry = path->dentry; - vfsmnt = path->mnt; - mnt = real_mount(vfsmnt); - read_seqbegin_or_lock(&rename_lock, &seq); - while (dentry != root->dentry || vfsmnt != root->mnt) { - struct dentry * parent; - - if (dentry == vfsmnt->mnt_root || IS_ROOT(dentry)) { - struct mount *parent = READ_ONCE(mnt->mnt_parent); - /* Escaped? */ - if (dentry != vfsmnt->mnt_root) { - bptr = *buffer; - blen = *buflen; - error = 3; - break; - } - /* Global root? */ - if (mnt != parent) { - dentry = READ_ONCE(mnt->mnt_mountpoint); - mnt = parent; - vfsmnt = &mnt->mnt; - continue; - } - if (!error) - error = is_mounted(vfsmnt) ? 1 : 2; - break; - } - parent = dentry->d_parent; - prefetch(parent); - error = prepend_name(&bptr, &blen, &dentry->d_name); - if (error) - break; - - dentry = parent; - } - if (!(seq & 1)) - rcu_read_unlock(); - if (need_seqretry(&rename_lock, seq)) { - seq = 1; - goto restart; - } - done_seqretry(&rename_lock, seq); - - if (!(m_seq & 1)) - rcu_read_unlock(); - if (need_seqretry(&mount_lock, m_seq)) { - m_seq = 1; - goto restart_mnt; - } - done_seqretry(&mount_lock, m_seq); - - if (error >= 0 && bptr == *buffer) { - if (--blen < 0) - error = -ENAMETOOLONG; - else - *--bptr = '/'; - } - *buffer = bptr; - *buflen = blen; - return error; -} - -/** - * __d_path - return the path of a dentry - * @path: the dentry/vfsmount to report - * @root: root vfsmnt/dentry - * @buf: buffer to return value in - * @buflen: buffer length - * - * Convert a dentry into an ASCII path name. - * - * Returns a pointer into the buffer or an error code if the - * path was too long. - * - * "buflen" should be positive. - * - * If the path is not reachable from the supplied root, return %NULL. - */ -char *__d_path(const struct path *path, - const struct path *root, - char *buf, int buflen) -{ - char *res = buf + buflen; - int error; - - prepend(&res, &buflen, "\0", 1); - error = prepend_path(path, root, &res, &buflen); - - if (error < 0) - return ERR_PTR(error); - if (error > 0) - return NULL; - return res; -} - -char *d_absolute_path(const struct path *path, - char *buf, int buflen) -{ - struct path root = {}; - char *res = buf + buflen; - int error; - - prepend(&res, &buflen, "\0", 1); - error = prepend_path(path, &root, &res, &buflen); - - if (error > 1) - error = -EINVAL; - if (error < 0) - return ERR_PTR(error); - return res; -} - -/* - * same as __d_path but appends "(deleted)" for unlinked files. - */ -static int path_with_deleted(const struct path *path, - const struct path *root, - char **buf, int *buflen) -{ - prepend(buf, buflen, "\0", 1); - if (d_unlinked(path->dentry)) { - int error = prepend(buf, buflen, " (deleted)", 10); - if (error) - return error; - } - - return prepend_path(path, root, buf, buflen); -} - -static int prepend_unreachable(char **buffer, int *buflen) -{ - return prepend(buffer, buflen, "(unreachable)", 13); -} - -static void get_fs_root_rcu(struct fs_struct *fs, struct path *root) -{ - unsigned seq; - - do { - seq = read_seqcount_begin(&fs->seq); - *root = fs->root; - } while (read_seqcount_retry(&fs->seq, seq)); -} - -/** - * d_path - return the path of a dentry - * @path: path to report - * @buf: buffer to return value in - * @buflen: buffer length - * - * Convert a dentry into an ASCII path name. If the entry has been deleted - * the string " (deleted)" is appended. Note that this is ambiguous. - * - * Returns a pointer into the buffer or an error code if the path was - * too long. Note: Callers should use the returned pointer, not the passed - * in buffer, to use the name! The implementation often starts at an offset - * into the buffer, and may leave 0 bytes at the start. - * - * "buflen" should be positive. - */ -char *d_path(const struct path *path, char *buf, int buflen) -{ - char *res = buf + buflen; - struct path root; - int error; - - /* - * We have various synthetic filesystems that never get mounted. On - * these filesystems dentries are never used for lookup purposes, and - * thus don't need to be hashed. They also don't need a name until a - * user wants to identify the object in /proc/pid/fd/. The little hack - * below allows us to generate a name for these objects on demand: - * - * Some pseudo inodes are mountable. When they are mounted - * path->dentry == path->mnt->mnt_root. In that case don't call d_dname - * and instead have d_path return the mounted path. - */ - if (path->dentry->d_op && path->dentry->d_op->d_dname && - (!IS_ROOT(path->dentry) || path->dentry != path->mnt->mnt_root)) - return path->dentry->d_op->d_dname(path->dentry, buf, buflen); - - rcu_read_lock(); - get_fs_root_rcu(current->fs, &root); - error = path_with_deleted(path, &root, &res, &buflen); - rcu_read_unlock(); - - if (error < 0) - res = ERR_PTR(error); - return res; -} -EXPORT_SYMBOL(d_path); - -/* - * Helper function for dentry_operations.d_dname() members - */ -char *dynamic_dname(struct dentry *dentry, char *buffer, int buflen, - const char *fmt, ...) -{ - va_list args; - char temp[64]; - int sz; - - va_start(args, fmt); - sz = vsnprintf(temp, sizeof(temp), fmt, args) + 1; - va_end(args); - - if (sz > sizeof(temp) || sz > buflen) - return ERR_PTR(-ENAMETOOLONG); - - buffer += buflen - sz; - return memcpy(buffer, temp, sz); -} - -char *simple_dname(struct dentry *dentry, char *buffer, int buflen) -{ - char *end = buffer + buflen; - /* these dentries are never renamed, so d_lock is not needed */ - if (prepend(&end, &buflen, " (deleted)", 11) || - prepend(&end, &buflen, dentry->d_name.name, dentry->d_name.len) || - prepend(&end, &buflen, "/", 1)) - end = ERR_PTR(-ENAMETOOLONG); - return end; -} -EXPORT_SYMBOL(simple_dname); - -/* - * Write full pathname from the root of the filesystem into the buffer. - */ -static char *__dentry_path(struct dentry *d, char *buf, int buflen) -{ - struct dentry *dentry; - char *end, *retval; - int len, seq = 0; - int error = 0; - - if (buflen < 2) - goto Elong; - - rcu_read_lock(); -restart: - dentry = d; - end = buf + buflen; - len = buflen; - prepend(&end, &len, "\0", 1); - /* Get '/' right */ - retval = end-1; - *retval = '/'; - read_seqbegin_or_lock(&rename_lock, &seq); - while (!IS_ROOT(dentry)) { - struct dentry *parent = dentry->d_parent; - - prefetch(parent); - error = prepend_name(&end, &len, &dentry->d_name); - if (error) - break; - - retval = end; - dentry = parent; - } - if (!(seq & 1)) - rcu_read_unlock(); - if (need_seqretry(&rename_lock, seq)) { - seq = 1; - goto restart; - } - done_seqretry(&rename_lock, seq); - if (error) - goto Elong; - return retval; -Elong: - return ERR_PTR(-ENAMETOOLONG); -} - -char *dentry_path_raw(struct dentry *dentry, char *buf, int buflen) -{ - return __dentry_path(dentry, buf, buflen); -} -EXPORT_SYMBOL(dentry_path_raw); - -char *dentry_path(struct dentry *dentry, char *buf, int buflen) -{ - char *p = NULL; - char *retval; - - if (d_unlinked(dentry)) { - p = buf + buflen; - if (prepend(&p, &buflen, "//deleted", 10) != 0) - goto Elong; - buflen++; - } - retval = __dentry_path(dentry, buf, buflen); - if (!IS_ERR(retval) && p) - *p = '/'; /* restore '/' overriden with '\0' */ - return retval; -Elong: - return ERR_PTR(-ENAMETOOLONG); -} - -static void get_fs_root_and_pwd_rcu(struct fs_struct *fs, struct path *root, - struct path *pwd) -{ - unsigned seq; - - do { - seq = read_seqcount_begin(&fs->seq); - *root = fs->root; - *pwd = fs->pwd; - } while (read_seqcount_retry(&fs->seq, seq)); -} - -/* - * NOTE! The user-level library version returns a - * character pointer. The kernel system call just - * returns the length of the buffer filled (which - * includes the ending '\0' character), or a negative - * error value. So libc would do something like - * - * char *getcwd(char * buf, size_t size) - * { - * int retval; - * - * retval = sys_getcwd(buf, size); - * if (retval >= 0) - * return buf; - * errno = -retval; - * return NULL; - * } - */ -SYSCALL_DEFINE2(getcwd, char __user *, buf, unsigned long, size) -{ - int error; - struct path pwd, root; - char *page = __getname(); - - if (!page) - return -ENOMEM; - - rcu_read_lock(); - get_fs_root_and_pwd_rcu(current->fs, &root, &pwd); - - error = -ENOENT; - if (!d_unlinked(pwd.dentry)) { - unsigned long len; - char *cwd = page + PATH_MAX; - int buflen = PATH_MAX; - - prepend(&cwd, &buflen, "\0", 1); - error = prepend_path(&pwd, &root, &cwd, &buflen); - rcu_read_unlock(); - - if (error < 0) - goto out; - - /* Unreachable from current root */ - if (error > 0) { - error = prepend_unreachable(&cwd, &buflen); - if (error) - goto out; - } - - error = -ERANGE; - len = PATH_MAX + page - cwd; - if (len <= size) { - error = len; - if (copy_to_user(buf, cwd, len)) - error = -EFAULT; - } - } else { - rcu_read_unlock(); - } - -out: - __putname(page); - return error; -} - /* * Test whether new_dentry is a subdirectory of old_dentry. * @ fs/dcache.c:3125 @ void d_genocide(struct dentry *parent) d_walk(parent, parent, d_genocide_kill, NULL); } +EXPORT_SYMBOL(d_genocide); + void d_tmpfile(struct dentry *dentry, struct inode *inode) { inode_dec_link_count(inode); @ fs/dcache.c:3155 @ __setup("dhash_entries=", set_dhash_entries); static void __init dcache_init_early(void) { + unsigned int loop; + /* If hashes are distributed across NUMA nodes, defer * hash allocation until vmalloc space is available. */ @ fs/dcache.c:3173 @ static void __init dcache_init_early(void) NULL, 0, 0); + + for (loop = 0; loop < (1U << d_hash_shift); loop++) + INIT_HLIST_BL_HEAD(dentry_hashtable + loop); + d_hash_shift = 32 - d_hash_shift; } static void __init dcache_init(void) { + unsigned int loop; /* * A constructor could be added for stable state like the lists, * but it is probably not worth it because of the cache nature @ fs/dcache.c:3206 @ static void __init dcache_init(void) NULL, 0, 0); + + for (loop = 0; loop < (1U << d_hash_shift); loop++) + INIT_HLIST_BL_HEAD(dentry_hashtable + loop); + d_hash_shift = 32 - d_hash_shift; } @ fs/dcache.c:3217 @ static void __init dcache_init(void) struct kmem_cache *names_cachep __read_mostly; EXPORT_SYMBOL(names_cachep); -EXPORT_SYMBOL(d_genocide); - void __init vfs_caches_init_early(void) { int i; @ fs/debugfs/inode.c:273 @ struct dentry *debugfs_lookup(const char *name, struct dentry *parent) if (!parent) parent = debugfs_mount->mnt_root; - inode_lock(d_inode(parent)); - dentry = lookup_one_len(name, parent, strlen(name)); - inode_unlock(d_inode(parent)); - + dentry = lookup_one_len_unlocked(name, parent, strlen(name)); if (IS_ERR(dentry)) return NULL; if (!d_really_is_positive(dentry)) { @ fs/eventpoll.c:566 @ static int ep_poll_wakeup_proc(void *priv, void *cookie, int call_nests) static void ep_poll_safewake(wait_queue_head_t *wq) { - int this_cpu = get_cpu(); + int this_cpu = get_cpu_light(); ep_call_nested(&poll_safewake_ncalls, EP_MAX_NESTS, ep_poll_wakeup_proc, NULL, wq, (void *) (long) this_cpu); - put_cpu(); + put_cpu_light(); } #else @ fs/exec.c:1027 @ static int exec_mmap(struct mm_struct *mm) } } task_lock(tsk); + preempt_disable_rt(); active_mm = tsk->active_mm; tsk->mm = mm; tsk->active_mm = mm; activate_mm(active_mm, mm); tsk->mm->vmacache_seqnum = 0; vmacache_flush(tsk); + preempt_enable_rt(); task_unlock(tsk); if (old_mm) { up_read(&old_mm->mmap_sem); @ fs/ext4/page-io.c:98 @ static void ext4_finish_bio(struct bio *bio) * We check all buffers in the page under BH_Uptodate_Lock * to avoid races with other end io clearing async_write flags */ - local_irq_save(flags); - bit_spin_lock(BH_Uptodate_Lock, &head->b_state); + flags = bh_uptodate_lock_irqsave(head); do { if (bh_offset(bh) < bio_start || bh_offset(bh) + bh->b_size > bio_end) { @ fs/ext4/page-io.c:110 @ static void ext4_finish_bio(struct bio *bio) if (bio->bi_status) buffer_io_error(bh); } while ((bh = bh->b_this_page) != head); - bit_spin_unlock(BH_Uptodate_Lock, &head->b_state); - local_irq_restore(flags); + bh_uptodate_unlock_irqrestore(head, flags); if (!under_io) { #ifdef CONFIG_EXT4_FS_ENCRYPTION if (data_page) @ fs/fuse/dir.c:1190 @ static int fuse_direntplus_link(struct file *file, struct inode *dir = d_inode(parent); struct fuse_conn *fc; struct inode *inode; - DECLARE_WAIT_QUEUE_HEAD_ONSTACK(wq); + DECLARE_SWAIT_QUEUE_HEAD_ONSTACK(wq); if (!o->nodeid) { /* @ fs/inode.c:158 @ int inode_init_always(struct super_block *sb, struct inode *inode) inode->i_bdev = NULL; inode->i_cdev = NULL; inode->i_link = NULL; - inode->i_dir_seq = 0; + inode->__i_dir_seq = 0; inode->i_rdev = 0; inode->dirtied_when = 0; @ fs/libfs.c:93 @ static struct dentry *next_positive(struct dentry *parent, struct list_head *from, int count) { - unsigned *seq = &parent->d_inode->i_dir_seq, n; + unsigned *seq = &parent->d_inode->__i_dir_seq, n; struct dentry *res; struct list_head *p; bool skipped; @ fs/libfs.c:126 @ static struct dentry *next_positive(struct dentry *parent, static void move_cursor(struct dentry *cursor, struct list_head *after) { struct dentry *parent = cursor->d_parent; - unsigned n, *seq = &parent->d_inode->i_dir_seq; + unsigned n, *seq = &parent->d_inode->__i_dir_seq; spin_lock(&parent->d_lock); + preempt_disable_rt(); for (;;) { n = *seq; if (!(n & 1) && cmpxchg(seq, n, n + 1) == n) @ fs/libfs.c:141 @ static void move_cursor(struct dentry *cursor, struct list_head *after) else list_add_tail(&cursor->d_child, &parent->d_subdirs); smp_store_release(seq, n + 2); + preempt_enable_rt(); spin_unlock(&parent->d_lock); } @ fs/locks.c:948 @ static int flock_lock_inode(struct inode *inode, struct file_lock *request) return -ENOMEM; } - percpu_down_read_preempt_disable(&file_rwsem); + percpu_down_read(&file_rwsem); spin_lock(&ctx->flc_lock); if (request->fl_flags & FL_ACCESS) goto find_conflict; @ fs/locks.c:989 @ static int flock_lock_inode(struct inode *inode, struct file_lock *request) out: spin_unlock(&ctx->flc_lock); - percpu_up_read_preempt_enable(&file_rwsem); + percpu_up_read(&file_rwsem); if (new_fl) locks_free_lock(new_fl); locks_dispose_list(&dispose); @ fs/locks.c:1026 @ static int posix_lock_inode(struct inode *inode, struct file_lock *request, new_fl2 = locks_alloc_lock(); } - percpu_down_read_preempt_disable(&file_rwsem); + percpu_down_read(&file_rwsem); spin_lock(&ctx->flc_lock); /* * New lock request. Walk all POSIX locks and look for conflicts. If @ fs/locks.c:1198 @ static int posix_lock_inode(struct inode *inode, struct file_lock *request, } out: spin_unlock(&ctx->flc_lock); - percpu_up_read_preempt_enable(&file_rwsem); + percpu_up_read(&file_rwsem); /* * Free any unused locks. */ @ fs/locks.c:1473 @ int __break_lease(struct inode *inode, unsigned int mode, unsigned int type) return error; } - percpu_down_read_preempt_disable(&file_rwsem); + percpu_down_read(&file_rwsem); spin_lock(&ctx->flc_lock); time_out_leases(inode, &dispose); @ fs/locks.c:1525 @ int __break_lease(struct inode *inode, unsigned int mode, unsigned int type) locks_insert_block(fl, new_fl); trace_break_lease_block(inode, new_fl); spin_unlock(&ctx->flc_lock); - percpu_up_read_preempt_enable(&file_rwsem); + percpu_up_read(&file_rwsem); locks_dispose_list(&dispose); error = wait_event_interruptible_timeout(new_fl->fl_wait, !new_fl->fl_next, break_time); - percpu_down_read_preempt_disable(&file_rwsem); + percpu_down_read(&file_rwsem); spin_lock(&ctx->flc_lock); trace_break_lease_unblock(inode, new_fl); locks_delete_block(new_fl); @ fs/locks.c:1548 @ int __break_lease(struct inode *inode, unsigned int mode, unsigned int type) } out: spin_unlock(&ctx->flc_lock); - percpu_up_read_preempt_enable(&file_rwsem); + percpu_up_read(&file_rwsem); locks_dispose_list(&dispose); locks_free_lock(new_fl); return error; @ fs/locks.c:1620 @ int fcntl_getlease(struct file *filp) ctx = smp_load_acquire(&inode->i_flctx); if (ctx && !list_empty_careful(&ctx->flc_lease)) { - percpu_down_read_preempt_disable(&file_rwsem); + percpu_down_read(&file_rwsem); spin_lock(&ctx->flc_lock); time_out_leases(inode, &dispose); list_for_each_entry(fl, &ctx->flc_lease, fl_list) { @ fs/locks.c:1630 @ int fcntl_getlease(struct file *filp) break; } spin_unlock(&ctx->flc_lock); - percpu_up_read_preempt_enable(&file_rwsem); + percpu_up_read(&file_rwsem); locks_dispose_list(&dispose); } @ fs/locks.c:1705 @ generic_add_lease(struct file *filp, long arg, struct file_lock **flp, void **pr return -EINVAL; } - percpu_down_read_preempt_disable(&file_rwsem); + percpu_down_read(&file_rwsem); spin_lock(&ctx->flc_lock); time_out_leases(inode, &dispose); error = check_conflicting_open(dentry, arg, lease->fl_flags); @ fs/locks.c:1776 @ generic_add_lease(struct file *filp, long arg, struct file_lock **flp, void **pr lease->fl_lmops->lm_setup(lease, priv); out: spin_unlock(&ctx->flc_lock); - percpu_up_read_preempt_enable(&file_rwsem); + percpu_up_read(&file_rwsem); locks_dispose_list(&dispose); if (is_deleg) inode_unlock(inode); @ fs/locks.c:1799 @ static int generic_delete_lease(struct file *filp, void *owner) return error; } - percpu_down_read_preempt_disable(&file_rwsem); + percpu_down_read(&file_rwsem); spin_lock(&ctx->flc_lock); list_for_each_entry(fl, &ctx->flc_lease, fl_list) { if (fl->fl_file == filp && @ fs/locks.c:1812 @ static int generic_delete_lease(struct file *filp, void *owner) if (victim) error = fl->fl_lmops->lm_change(victim, F_UNLCK, &dispose); spin_unlock(&ctx->flc_lock); - percpu_up_read_preempt_enable(&file_rwsem); + percpu_up_read(&file_rwsem); locks_dispose_list(&dispose); return error; } @ fs/locks.c:2536 @ locks_remove_lease(struct file *filp, struct file_lock_context *ctx) if (list_empty(&ctx->flc_lease)) return; - percpu_down_read_preempt_disable(&file_rwsem); + percpu_down_read(&file_rwsem); spin_lock(&ctx->flc_lock); list_for_each_entry_safe(fl, tmp, &ctx->flc_lease, fl_list) if (filp == fl->fl_file) lease_modify(fl, F_UNLCK, &dispose); spin_unlock(&ctx->flc_lock); - percpu_up_read_preempt_enable(&file_rwsem); + percpu_up_read(&file_rwsem); locks_dispose_list(&dispose); } @ fs/namei.c:1478 @ static struct dentry *lookup_dcache(const struct qstr *name, } /* - * Call i_op->lookup on the dentry. The dentry must be negative and - * unhashed. - * - * dir->d_inode->i_mutex must be held + * Parent directory has inode locked exclusive. This is one + * and only case when ->lookup() gets called on non in-lookup + * dentries - as the matter of fact, this only gets called + * when directory is guaranteed to have no in-lookup children + * at all. */ -static struct dentry *lookup_real(struct inode *dir, struct dentry *dentry, - unsigned int flags) +static struct dentry *__lookup_hash(const struct qstr *name, + struct dentry *base, unsigned int flags) { + struct dentry *dentry = lookup_dcache(name, base, flags); struct dentry *old; + struct inode *dir = base->d_inode; + + if (dentry) + return dentry; /* Don't create child dentry for a dead directory. */ - if (unlikely(IS_DEADDIR(dir))) { - dput(dentry); + if (unlikely(IS_DEADDIR(dir))) return ERR_PTR(-ENOENT); - } + + dentry = d_alloc(base, name); + if (unlikely(!dentry)) + return ERR_PTR(-ENOMEM); old = dir->i_op->lookup(dir, dentry, flags); if (unlikely(old)) { @ fs/namei.c:1510 @ static struct dentry *lookup_real(struct inode *dir, struct dentry *dentry, return dentry; } -static struct dentry *__lookup_hash(const struct qstr *name, - struct dentry *base, unsigned int flags) -{ - struct dentry *dentry = lookup_dcache(name, base, flags); - - if (dentry) - return dentry; - - dentry = d_alloc(base, name); - if (unlikely(!dentry)) - return ERR_PTR(-ENOMEM); - - return lookup_real(base->d_inode, dentry, flags); -} - static int lookup_fast(struct nameidata *nd, struct path *path, struct inode **inode, unsigned *seqp) @ fs/namei.c:1604 @ static struct dentry *lookup_slow(const struct qstr *name, { struct dentry *dentry = ERR_PTR(-ENOENT), *old; struct inode *inode = dir->d_inode; - DECLARE_WAIT_QUEUE_HEAD_ONSTACK(wq); + DECLARE_SWAIT_QUEUE_HEAD_ONSTACK(wq); inode_lock_shared(inode); /* Don't go there if it's already dead */ @ fs/namei.c:3098 @ static int lookup_open(struct nameidata *nd, struct path *path, struct dentry *dentry; int error, create_error = 0; umode_t mode = op->mode; - DECLARE_WAIT_QUEUE_HEAD_ONSTACK(wq); + DECLARE_SWAIT_QUEUE_HEAD_ONSTACK(wq); if (unlikely(IS_DEADDIR(dir_inode))) return -ENOENT; @ fs/namespace.c:17 @ #include <linux/mnt_namespace.h> #include <linux/user_namespace.h> #include <linux/namei.h> +#include <linux/delay.h> #include <linux/security.h> #include <linux/cred.h> #include <linux/idr.h> @ fs/namespace.c:357 @ int __mnt_want_write(struct vfsmount *m) * incremented count after it has set MNT_WRITE_HOLD. */ smp_mb(); - while (READ_ONCE(mnt->mnt.mnt_flags) & MNT_WRITE_HOLD) - cpu_relax(); + while (READ_ONCE(mnt->mnt.mnt_flags) & MNT_WRITE_HOLD) { + preempt_enable(); + cpu_chill(); + preempt_disable(); + } /* * After the slowpath clears MNT_WRITE_HOLD, mnt_is_readonly will * be set to match its requirements. So we must not load that until @ fs/nfs/delegation.c:154 @ static int nfs_delegation_claim_opens(struct inode *inode, sp = state->owner; /* Block nfs4_proc_unlck */ mutex_lock(&sp->so_delegreturn_mutex); - seq = raw_seqcount_begin(&sp->so_reclaim_seqcount); + seq = read_seqbegin(&sp->so_reclaim_seqlock); err = nfs4_open_delegation_recall(ctx, state, stateid, type); if (!err) err = nfs_delegation_claim_locks(ctx, state, stateid); - if (!err && read_seqcount_retry(&sp->so_reclaim_seqcount, seq)) + if (!err && read_seqretry(&sp->so_reclaim_seqlock, seq)) err = -EAGAIN; mutex_unlock(&sp->so_delegreturn_mutex); put_nfs_open_context(ctx); @ fs/nfs/dir.c:448 @ static void nfs_prime_dcache(struct dentry *parent, struct nfs_entry *entry) { struct qstr filename = QSTR_INIT(entry->name, entry->len); - DECLARE_WAIT_QUEUE_HEAD_ONSTACK(wq); + DECLARE_SWAIT_QUEUE_HEAD_ONSTACK(wq); struct dentry *dentry; struct dentry *alias; struct inode *dir = d_inode(parent); @ fs/nfs/dir.c:1439 @ int nfs_atomic_open(struct inode *dir, struct dentry *dentry, struct file *file, unsigned open_flags, umode_t mode, int *opened) { - DECLARE_WAIT_QUEUE_HEAD_ONSTACK(wq); + DECLARE_SWAIT_QUEUE_HEAD_ONSTACK(wq); struct nfs_open_context *ctx; struct dentry *res; struct iattr attr = { .ia_valid = ATTR_OPEN }; @ fs/nfs/dir.c:1759 @ int nfs_rmdir(struct inode *dir, struct dentry *dentry) trace_nfs_rmdir_enter(dir, dentry); if (d_really_is_positive(dentry)) { +#ifdef CONFIG_PREEMPT_RT_BASE + down(&NFS_I(d_inode(dentry))->rmdir_sem); +#else down_write(&NFS_I(d_inode(dentry))->rmdir_sem); +#endif error = NFS_PROTO(dir)->rmdir(dir, &dentry->d_name); /* Ensure the VFS deletes this inode */ switch (error) { @ fs/nfs/dir.c:1773 @ int nfs_rmdir(struct inode *dir, struct dentry *dentry) case -ENOENT: nfs_dentry_handle_enoent(dentry); } +#ifdef CONFIG_PREEMPT_RT_BASE + up(&NFS_I(d_inode(dentry))->rmdir_sem); +#else up_write(&NFS_I(d_inode(dentry))->rmdir_sem); +#endif } else error = NFS_PROTO(dir)->rmdir(dir, &dentry->d_name); trace_nfs_rmdir_exit(dir, dentry, error); @ fs/nfs/inode.c:2042 @ static void init_once(void *foo) atomic_long_set(&nfsi->nrequests, 0); atomic_long_set(&nfsi->commit_info.ncommit, 0); atomic_set(&nfsi->commit_info.rpcs_out, 0); +#ifdef CONFIG_PREEMPT_RT_BASE + sema_init(&nfsi->rmdir_sem, 1); +#else init_rwsem(&nfsi->rmdir_sem); +#endif mutex_init(&nfsi->commit_mutex); nfs4_init_once(nfsi); } @ fs/nfs/nfs4_fs.h:115 @ struct nfs4_state_owner { unsigned long so_flags; struct list_head so_states; struct nfs_seqid_counter so_seqid; - seqcount_t so_reclaim_seqcount; + seqlock_t so_reclaim_seqlock; struct mutex so_delegreturn_mutex; }; @ fs/nfs/nfs4proc.c:2781 @ static int _nfs4_open_and_get_state(struct nfs4_opendata *opendata, unsigned int seq; int ret; - seq = raw_seqcount_begin(&sp->so_reclaim_seqcount); + seq = raw_seqcount_begin(&sp->so_reclaim_seqlock.seqcount); ret = _nfs4_proc_open(opendata); if (ret != 0) @ fs/nfs/nfs4proc.c:2819 @ static int _nfs4_open_and_get_state(struct nfs4_opendata *opendata, if (d_inode(dentry) == state->inode) { nfs_inode_attach_open_context(ctx); - if (read_seqcount_retry(&sp->so_reclaim_seqcount, seq)) + if (read_seqretry(&sp->so_reclaim_seqlock, seq)) nfs4_schedule_stateid_recovery(server, state); } out: @ fs/nfs/nfs4state.c:505 @ nfs4_alloc_state_owner(struct nfs_server *server, nfs4_init_seqid_counter(&sp->so_seqid); atomic_set(&sp->so_count, 1); INIT_LIST_HEAD(&sp->so_lru); - seqcount_init(&sp->so_reclaim_seqcount); + seqlock_init(&sp->so_reclaim_seqlock); mutex_init(&sp->so_delegreturn_mutex); return sp; } @ fs/nfs/nfs4state.c:1557 @ static int nfs4_reclaim_open_state(struct nfs4_state_owner *sp, const struct nfs * recovering after a network partition or a reboot from a * server that doesn't support a grace period. */ +#ifdef CONFIG_PREEMPT_RT_FULL + write_seqlock(&sp->so_reclaim_seqlock); +#else + write_seqcount_begin(&sp->so_reclaim_seqlock.seqcount); +#endif spin_lock(&sp->so_lock); - raw_write_seqcount_begin(&sp->so_reclaim_seqcount); restart: list_for_each_entry(state, &sp->so_states, open_states) { if (!test_and_clear_bit(ops->state_flag_bit, &state->flags)) @ fs/nfs/nfs4state.c:1631 @ static int nfs4_reclaim_open_state(struct nfs4_state_owner *sp, const struct nfs spin_lock(&sp->so_lock); goto restart; } - raw_write_seqcount_end(&sp->so_reclaim_seqcount); spin_unlock(&sp->so_lock); +#ifdef CONFIG_PREEMPT_RT_FULL + write_sequnlock(&sp->so_reclaim_seqlock); +#else + write_seqcount_end(&sp->so_reclaim_seqlock.seqcount); +#endif return 0; out_err: nfs4_put_open_state(state); - spin_lock(&sp->so_lock); - raw_write_seqcount_end(&sp->so_reclaim_seqcount); - spin_unlock(&sp->so_lock); +#ifdef CONFIG_PREEMPT_RT_FULL + write_sequnlock(&sp->so_reclaim_seqlock); +#else + write_seqcount_end(&sp->so_reclaim_seqlock.seqcount); +#endif return status; } @ fs/nfs/unlink.c:16 @ #include <linux/sunrpc/clnt.h> #include <linux/nfs_fs.h> #include <linux/sched.h> -#include <linux/wait.h> +#include <linux/swait.h> #include <linux/namei.h> #include <linux/fsnotify.h> @ fs/nfs/unlink.c:55 @ static void nfs_async_unlink_done(struct rpc_task *task, void *calldata) rpc_restart_call_prepare(task); } +#ifdef CONFIG_PREEMPT_RT_BASE +static void nfs_down_anon(struct semaphore *sema) +{ + down(sema); +} + +static void nfs_up_anon(struct semaphore *sema) +{ + up(sema); +} + +#else +static void nfs_down_anon(struct rw_semaphore *rwsem) +{ + down_read_non_owner(rwsem); +} + +static void nfs_up_anon(struct rw_semaphore *rwsem) +{ + up_read_non_owner(rwsem); +} +#endif + /** * nfs_async_unlink_release - Release the sillydelete data. * @task: rpc_task of the sillydelete @ fs/nfs/unlink.c:91 @ static void nfs_async_unlink_release(void *calldata) struct dentry *dentry = data->dentry; struct super_block *sb = dentry->d_sb; - up_read_non_owner(&NFS_I(d_inode(dentry->d_parent))->rmdir_sem); + nfs_up_anon(&NFS_I(d_inode(dentry->d_parent))->rmdir_sem); d_lookup_done(dentry); nfs_free_unlinkdata(data); dput(dentry); @ fs/nfs/unlink.c:144 @ static int nfs_call_unlink(struct dentry *dentry, struct nfs_unlinkdata *data) struct inode *dir = d_inode(dentry->d_parent); struct dentry *alias; - down_read_non_owner(&NFS_I(dir)->rmdir_sem); + nfs_down_anon(&NFS_I(dir)->rmdir_sem); alias = d_alloc_parallel(dentry->d_parent, &data->args.name, &data->wq); if (IS_ERR(alias)) { - up_read_non_owner(&NFS_I(dir)->rmdir_sem); + nfs_up_anon(&NFS_I(dir)->rmdir_sem); return 0; } if (!d_in_lookup(alias)) { @ fs/nfs/unlink.c:169 @ static int nfs_call_unlink(struct dentry *dentry, struct nfs_unlinkdata *data) ret = 0; spin_unlock(&alias->d_lock); dput(alias); - up_read_non_owner(&NFS_I(dir)->rmdir_sem); + nfs_up_anon(&NFS_I(dir)->rmdir_sem); /* * If we'd displaced old cached devname, free it. At that * point dentry is definitely not a root, so we won't need @ fs/nfs/unlink.c:209 @ nfs_async_unlink(struct dentry *dentry, const struct qstr *name) goto out_free_name; } data->res.dir_attr = &data->dir_attr; - init_waitqueue_head(&data->wq); + init_swait_queue_head(&data->wq); status = -EBUSY; spin_lock(&dentry->d_lock); @ fs/ntfs/aops.c:96 @ static void ntfs_end_buffer_async_read(struct buffer_head *bh, int uptodate) ofs = 0; if (file_ofs < init_size) ofs = init_size - file_ofs; - local_irq_save(flags); kaddr = kmap_atomic(page); memset(kaddr + bh_offset(bh) + ofs, 0, bh->b_size - ofs); flush_dcache_page(page); kunmap_atomic(kaddr); - local_irq_restore(flags); } } else { clear_buffer_uptodate(bh); @ fs/ntfs/aops.c:109 @ static void ntfs_end_buffer_async_read(struct buffer_head *bh, int uptodate) "0x%llx.", (unsigned long long)bh->b_blocknr); } first = page_buffers(page); - local_irq_save(flags); - bit_spin_lock(BH_Uptodate_Lock, &first->b_state); + flags = bh_uptodate_lock_irqsave(first); clear_buffer_async_read(bh); unlock_buffer(bh); tmp = bh; @ fs/ntfs/aops.c:124 @ static void ntfs_end_buffer_async_read(struct buffer_head *bh, int uptodate) } tmp = tmp->b_this_page; } while (tmp != bh); - bit_spin_unlock(BH_Uptodate_Lock, &first->b_state); - local_irq_restore(flags); + bh_uptodate_unlock_irqrestore(first, flags); /* * If none of the buffers had errors then we can set the page uptodate, * but we first have to perform the post read mst fixups, if the @ fs/ntfs/aops.c:145 @ static void ntfs_end_buffer_async_read(struct buffer_head *bh, int uptodate) recs = PAGE_SIZE / rec_size; /* Should have been verified before we got here... */ BUG_ON(!recs); - local_irq_save(flags); kaddr = kmap_atomic(page); for (i = 0; i < recs; i++) post_read_mst_fixup((NTFS_RECORD*)(kaddr + i * rec_size), rec_size); kunmap_atomic(kaddr); - local_irq_restore(flags); flush_dcache_page(page); if (likely(page_uptodate && !PageError(page))) SetPageUptodate(page); @ fs/ntfs/aops.c:157 @ static void ntfs_end_buffer_async_read(struct buffer_head *bh, int uptodate) unlock_page(page); return; still_busy: - bit_spin_unlock(BH_Uptodate_Lock, &first->b_state); - local_irq_restore(flags); - return; + bh_uptodate_unlock_irqrestore(first, flags); } /** @ fs/proc/array.c:389 @ static inline void task_context_switch_counts(struct seq_file *m, static void task_cpus_allowed(struct seq_file *m, struct task_struct *task) { seq_printf(m, "Cpus_allowed:\t%*pb\n", - cpumask_pr_args(&task->cpus_allowed)); + cpumask_pr_args(task->cpus_ptr)); seq_printf(m, "Cpus_allowed_list:\t%*pbl\n", - cpumask_pr_args(&task->cpus_allowed)); + cpumask_pr_args(task->cpus_ptr)); } static inline void task_core_dumping(struct seq_file *m, struct mm_struct *mm) @ fs/proc/base.c:1882 @ bool proc_fill_cache(struct file *file, struct dir_context *ctx, child = d_hash_and_lookup(dir, &qname); if (!child) { - DECLARE_WAIT_QUEUE_HEAD_ONSTACK(wq); + DECLARE_SWAIT_QUEUE_HEAD_ONSTACK(wq); child = d_alloc_parallel(dir, &qname, &wq); if (IS_ERR(child)) goto end_instantiate; @ fs/proc/proc_sysctl.c:682 @ static bool proc_sys_fill_cache(struct file *file, child = d_lookup(dir, &qname); if (!child) { - DECLARE_WAIT_QUEUE_HEAD_ONSTACK(wq); + DECLARE_SWAIT_QUEUE_HEAD_ONSTACK(wq); child = d_alloc_parallel(dir, &qname, &wq); if (IS_ERR(child)) return false; @ fs/squashfs/decompressor_multi_percpu.c:13 @ #include <linux/slab.h> #include <linux/percpu.h> #include <linux/buffer_head.h> +#include <linux/locallock.h> #include "squashfs_fs.h" #include "squashfs_fs_sb.h" @ fs/squashfs/decompressor_multi_percpu.c:29 @ struct squashfs_stream { void *stream; }; +static DEFINE_LOCAL_IRQ_LOCK(stream_lock); + void *squashfs_decompressor_create(struct squashfs_sb_info *msblk, void *comp_opts) { @ fs/squashfs/decompressor_multi_percpu.c:85 @ int squashfs_decompress(struct squashfs_sb_info *msblk, struct buffer_head **bh, { struct squashfs_stream __percpu *percpu = (struct squashfs_stream __percpu *) msblk->stream; - struct squashfs_stream *stream = get_cpu_ptr(percpu); - int res = msblk->decompressor->decompress(msblk, stream->stream, bh, b, - offset, length, output); - put_cpu_ptr(stream); + struct squashfs_stream *stream; + int res; + + stream = get_locked_ptr(stream_lock, percpu); + + res = msblk->decompressor->decompress(msblk, stream->stream, bh, b, + offset, length, output); + + put_locked_ptr(stream_lock, stream); if (res < 0) ERROR("%s decompression failed, data probably corrupt\n", @ fs/timerfd.c:474 @ static int do_timerfd_settime(int ufd, int flags, break; } spin_unlock_irq(&ctx->wqh.lock); - cpu_relax(); + if (isalarm(ctx)) + hrtimer_wait_for_timer(&ctx->t.alarm.timer); + else + hrtimer_wait_for_timer(&ctx->t.tmr); } /* @ fs/xfs/xfs_aops.c:123 @ xfs_finish_page_writeback( ASSERT(bvec->bv_offset + bvec->bv_len <= PAGE_SIZE); ASSERT((bvec->bv_len & (i_blocksize(inode) - 1)) == 0); - local_irq_save(flags); - bit_spin_lock(BH_Uptodate_Lock, &head->b_state); + flags = bh_uptodate_lock_irqsave(head); do { if (off >= bvec->bv_offset && off < bvec->bv_offset + bvec->bv_len) { @ fs/xfs/xfs_aops.c:145 @ xfs_finish_page_writeback( } off += bh->b_size; } while ((bh = bh->b_this_page) != head); - bit_spin_unlock(BH_Uptodate_Lock, &head->b_state); - local_irq_restore(flags); + bh_uptodate_unlock_irqrestore(head, flags); if (!busy) end_page_writeback(bvec->bv_page); @ include/acpi/acpiosxf.h:134 @ acpi_cpu_flags acpi_os_acquire_lock(acpi_spinlock handle); void acpi_os_release_lock(acpi_spinlock handle, acpi_cpu_flags flags); #endif +/* + * RAW spinlock primitives. If the OS does not provide them, fallback to + * spinlock primitives + */ +#ifndef ACPI_USE_ALTERNATE_PROTOTYPE_acpi_os_create_raw_lock +# define acpi_os_create_raw_lock(out_handle) acpi_os_create_lock(out_handle) +#endif + +#ifndef ACPI_USE_ALTERNATE_PROTOTYPE_acpi_os_delete_raw_lock +# define acpi_os_delete_raw_lock(handle) acpi_os_delete_lock(handle) +#endif + +#ifndef ACPI_USE_ALTERNATE_PROTOTYPE_acpi_os_acquire_raw_lock +# define acpi_os_acquire_raw_lock(handle) acpi_os_acquire_lock(handle) +#endif + +#ifndef ACPI_USE_ALTERNATE_PROTOTYPE_acpi_os_release_raw_lock +# define acpi_os_release_raw_lock(handle, flags) \ + acpi_os_release_lock(handle, flags) +#endif + /* * Semaphore primitives */ @ include/acpi/actypes.h:282 @ typedef u64 acpi_physical_address; #define acpi_spinlock void * #endif +#ifndef acpi_raw_spinlock +#define acpi_raw_spinlock acpi_spinlock +#endif + #ifndef acpi_semaphore #define acpi_semaphore void * #endif @ include/acpi/platform/aclinux.h:137 @ #define acpi_cache_t struct kmem_cache #define acpi_spinlock spinlock_t * +#define acpi_raw_spinlock raw_spinlock_t * #define acpi_cpu_flags unsigned long /* Use native linux version of acpi_os_allocate_zeroed */ @ include/acpi/platform/aclinux.h:155 @ #define ACPI_USE_ALTERNATE_PROTOTYPE_acpi_os_acquire_object #define ACPI_USE_ALTERNATE_PROTOTYPE_acpi_os_get_thread_id #define ACPI_USE_ALTERNATE_PROTOTYPE_acpi_os_create_lock +#define ACPI_USE_ALTERNATE_PROTOTYPE_acpi_os_create_raw_lock +#define ACPI_USE_ALTERNATE_PROTOTYPE_acpi_os_delete_raw_lock +#define ACPI_USE_ALTERNATE_PROTOTYPE_acpi_os_acquire_raw_lock +#define ACPI_USE_ALTERNATE_PROTOTYPE_acpi_os_release_raw_lock /* * OSL interfaces used by debugger/disassembler @ include/acpi/platform/aclinuxex.h:127 @ static inline acpi_thread_id acpi_os_get_thread_id(void) lock ? AE_OK : AE_NO_MEMORY; \ }) + +#define acpi_os_create_raw_lock(__handle) \ + ({ \ + raw_spinlock_t *lock = ACPI_ALLOCATE(sizeof(*lock)); \ + if (lock) { \ + *(__handle) = lock; \ + raw_spin_lock_init(*(__handle)); \ + } \ + lock ? AE_OK : AE_NO_MEMORY; \ + }) + +static inline acpi_cpu_flags acpi_os_acquire_raw_lock(acpi_raw_spinlock lockp) +{ + acpi_cpu_flags flags; + + raw_spin_lock_irqsave(lockp, flags); + return flags; +} + +static inline void acpi_os_release_raw_lock(acpi_raw_spinlock lockp, + acpi_cpu_flags flags) +{ + raw_spin_unlock_irqrestore(lockp, flags); +} + +static inline void acpi_os_delete_raw_lock(acpi_raw_spinlock handle) +{ + ACPI_FREE(handle); +} + static inline u8 acpi_os_readable(void *pointer, acpi_size length) { return TRUE; @ include/linux/backing-dev-defs.h:15 @ #include <linux/timer.h> #include <linux/workqueue.h> #include <linux/kref.h> +#include <linux/refcount.h> struct page; struct device; @ include/linux/backing-dev-defs.h:80 @ enum wb_reason { */ struct bdi_writeback_congested { unsigned long state; /* WB_[a]sync_congested flags */ - atomic_t refcnt; /* nr of attached wb's and blkg */ + refcount_t refcnt; /* nr of attached wb's and blkg */ #ifdef CONFIG_CGROUP_WRITEBACK struct backing_dev_info *__bdi; /* the associated bdi, set to NULL @ include/linux/backing-dev.h:406 @ static inline bool inode_cgwb_enabled(struct inode *inode) static inline struct bdi_writeback_congested * wb_congested_get_create(struct backing_dev_info *bdi, int blkcg_id, gfp_t gfp) { - atomic_inc(&bdi->wb_congested->refcnt); + refcount_inc(&bdi->wb_congested->refcnt); return bdi->wb_congested; } static inline void wb_congested_put(struct bdi_writeback_congested *congested) { - if (atomic_dec_and_test(&congested->refcnt)) + if (refcount_dec_and_test(&congested->refcnt)) kfree(congested); } @ include/linux/blk-mq.h:248 @ static inline u16 blk_mq_unique_tag_to_tag(u32 unique_tag) return unique_tag & BLK_MQ_UNIQUE_TAG_MASK; } - +void __blk_mq_complete_request_remote_work(struct work_struct *work); int blk_mq_request_started(struct request *rq); void blk_mq_start_request(struct request *rq); void blk_mq_end_request(struct request *rq, blk_status_t error); @ include/linux/blkdev.h:30 @ #include <linux/percpu-refcount.h> #include <linux/scatterlist.h> #include <linux/blkzoned.h> +#include <linux/swork.h> #include <linux/seqlock.h> #include <linux/u64_stats_sync.h> @ include/linux/blkdev.h:146 @ typedef __u32 __bitwise req_flags_t; */ struct request { struct request_queue *q; +#ifdef CONFIG_PREEMPT_RT_FULL + struct work_struct work; +#endif struct blk_mq_ctx *mq_ctx; int cpu; @ include/linux/blkdev.h:657 @ struct request_queue { #endif struct rcu_head rcu_head; wait_queue_head_t mq_freeze_wq; + struct swork_event mq_pcpu_wake; struct percpu_ref q_usage_counter; struct list_head all_q_node; @ include/linux/bottom_half.h:7 @ #include <linux/preempt.h> +#ifdef CONFIG_PREEMPT_RT_FULL + +extern void __local_bh_disable(void); +extern void _local_bh_enable(void); +extern void __local_bh_enable(void); + +static inline void local_bh_disable(void) +{ + __local_bh_disable(); +} + +static inline void __local_bh_disable_ip(unsigned long ip, unsigned int cnt) +{ + __local_bh_disable(); +} + +static inline void local_bh_enable(void) +{ + __local_bh_enable(); +} + +static inline void __local_bh_enable_ip(unsigned long ip, unsigned int cnt) +{ + __local_bh_enable(); +} + +static inline void local_bh_enable_ip(unsigned long ip) +{ + __local_bh_enable(); +} + +#else + #ifdef CONFIG_TRACE_IRQFLAGS extern void __local_bh_disable_ip(unsigned long ip, unsigned int cnt); #else @ include/linux/bottom_half.h:67 @ static inline void local_bh_enable(void) { __local_bh_enable_ip(_THIS_IP_, SOFTIRQ_DISABLE_OFFSET); } +#endif #endif /* _LINUX_BH_H */ @ include/linux/buffer_head.h:79 @ struct buffer_head { struct address_space *b_assoc_map; /* mapping this buffer is associated with */ atomic_t b_count; /* users using this buffer_head */ +#ifdef CONFIG_PREEMPT_RT_BASE + spinlock_t b_uptodate_lock; +#if IS_ENABLED(CONFIG_JBD2) + spinlock_t b_state_lock; + spinlock_t b_journal_head_lock; +#endif +#endif }; +static inline unsigned long bh_uptodate_lock_irqsave(struct buffer_head *bh) +{ + unsigned long flags; + +#ifndef CONFIG_PREEMPT_RT_BASE + local_irq_save(flags); + bit_spin_lock(BH_Uptodate_Lock, &bh->b_state); +#else + spin_lock_irqsave(&bh->b_uptodate_lock, flags); +#endif + return flags; +} + +static inline void +bh_uptodate_unlock_irqrestore(struct buffer_head *bh, unsigned long flags) +{ +#ifndef CONFIG_PREEMPT_RT_BASE + bit_spin_unlock(BH_Uptodate_Lock, &bh->b_state); + local_irq_restore(flags); +#else + spin_unlock_irqrestore(&bh->b_uptodate_lock, flags); +#endif +} + +static inline void buffer_head_init_locks(struct buffer_head *bh) +{ +#ifdef CONFIG_PREEMPT_RT_BASE + spin_lock_init(&bh->b_uptodate_lock); +#if IS_ENABLED(CONFIG_JBD2) + spin_lock_init(&bh->b_state_lock); + spin_lock_init(&bh->b_journal_head_lock); +#endif +#endif +} + /* * macro tricks to expand the set_buffer_foo(), clear_buffer_foo() * and buffer_foo() functions. @ include/linux/cgroup-defs.h:23 @ #include <linux/u64_stats_sync.h> #include <linux/workqueue.h> #include <linux/bpf-cgroup.h> +#include <linux/swork.h> #ifdef CONFIG_CGROUPS @ include/linux/cgroup-defs.h:157 @ struct cgroup_subsys_state { /* percpu_ref killing and RCU release */ struct rcu_head rcu_head; struct work_struct destroy_work; + struct swork_event destroy_swork; /* * PI: the parent css. Placed here for cache proximity to following @ include/linux/completion.h:12 @ * See kernel/sched/completion.c for details. */ -#include <linux/wait.h> +#include <linux/swait.h> /* * struct completion - structure used to maintain state for a "completion" @ include/linux/completion.h:28 @ */ struct completion { unsigned int done; - wait_queue_head_t wait; + struct swait_queue_head wait; }; #define init_completion_map(x, m) __init_completion(x) @ include/linux/completion.h:37 @ static inline void complete_acquire(struct completion *x) {} static inline void complete_release(struct completion *x) {} #define COMPLETION_INITIALIZER(work) \ - { 0, __WAIT_QUEUE_HEAD_INITIALIZER((work).wait) } + { 0, __SWAIT_QUEUE_HEAD_INITIALIZER((work).wait) } #define COMPLETION_INITIALIZER_ONSTACK_MAP(work, map) \ (*({ init_completion_map(&(work), &(map)); &(work); })) @ include/linux/completion.h:88 @ static inline void complete_release(struct completion *x) {} static inline void __init_completion(struct completion *x) { x->done = 0; - init_waitqueue_head(&x->wait); + init_swait_queue_head(&x->wait); } /** @ include/linux/cpu.h:111 @ extern void cpu_hotplug_disable(void); extern void cpu_hotplug_enable(void); void clear_tasks_mm_cpumask(int cpu); int cpu_down(unsigned int cpu); +extern void pin_current_cpu(void); +extern void unpin_current_cpu(void); #else /* CONFIG_HOTPLUG_CPU */ @ include/linux/cpu.h:123 @ static inline void cpus_read_unlock(void) { } static inline void lockdep_assert_cpus_held(void) { } static inline void cpu_hotplug_disable(void) { } static inline void cpu_hotplug_enable(void) { } +static inline void pin_current_cpu(void) { } +static inline void unpin_current_cpu(void) { } + #endif /* !CONFIG_HOTPLUG_CPU */ /* Wrappers which go away once all code is converted */ @ include/linux/dcache.h:59 @ struct qstr { #define QSTR_INIT(n,l) { { { .len = l } }, .name = n } -extern const char empty_string[]; extern const struct qstr empty_name; -extern const char slash_string[]; extern const struct qstr slash_name; struct dentry_stat_t { @ include/linux/dcache.h:108 @ struct dentry { union { struct list_head d_lru; /* LRU list */ - wait_queue_head_t *d_wait; /* in-lookup ones only */ + struct swait_queue_head *d_wait; /* in-lookup ones only */ }; struct list_head d_child; /* child of parent list */ struct list_head d_subdirs; /* our children */ @ include/linux/dcache.h:241 @ extern struct dentry * d_alloc(struct dentry *, const struct qstr *); extern struct dentry * d_alloc_anon(struct super_block *); extern struct dentry * d_alloc_pseudo(struct super_block *, const struct qstr *); extern struct dentry * d_alloc_parallel(struct dentry *, const struct qstr *, - wait_queue_head_t *); + struct swait_queue_head *); extern struct dentry * d_splice_alias(struct inode *, struct dentry *); extern struct dentry * d_add_ci(struct dentry *, struct inode *, struct qstr *); extern struct dentry * d_exact_alias(struct dentry *, struct inode *); @ include/linux/delay.h:67 @ static inline void ssleep(unsigned int seconds) msleep(seconds * 1000); } +#ifdef CONFIG_PREEMPT_RT_FULL +extern void cpu_chill(void); +#else +# define cpu_chill() cpu_relax() +#endif + #endif /* defined(_LINUX_DELAY_H) */ @ include/linux/delayacct.h:32 @ #ifdef CONFIG_TASK_DELAY_ACCT struct task_delay_info { - spinlock_t lock; + raw_spinlock_t lock; unsigned int flags; /* Private per-task flags */ /* For each stat XXX, add following, aligned appropriately @ include/linux/fs.h:658 @ struct inode { struct block_device *i_bdev; struct cdev *i_cdev; char *i_link; - unsigned i_dir_seq; + unsigned __i_dir_seq; }; __u32 i_generation; @ include/linux/highmem.h:11 @ #include <linux/mm.h> #include <linux/uaccess.h> #include <linux/hardirq.h> +#include <linux/sched.h> #include <asm/cacheflush.h> @ include/linux/highmem.h:70 @ static inline void kunmap(struct page *page) static inline void *kmap_atomic(struct page *page) { - preempt_disable(); + preempt_disable_nort(); pagefault_disable(); return page_address(page); } @ include/linux/highmem.h:79 @ static inline void *kmap_atomic(struct page *page) static inline void __kunmap_atomic(void *addr) { pagefault_enable(); - preempt_enable(); + preempt_enable_nort(); } #define kmap_atomic_pfn(pfn) kmap_atomic(pfn_to_page(pfn)) @ include/linux/highmem.h:91 @ static inline void __kunmap_atomic(void *addr) #if defined(CONFIG_HIGHMEM) || defined(CONFIG_X86_32) +#ifndef CONFIG_PREEMPT_RT_FULL DECLARE_PER_CPU(int, __kmap_atomic_idx); +#endif static inline int kmap_atomic_idx_push(void) { +#ifndef CONFIG_PREEMPT_RT_FULL int idx = __this_cpu_inc_return(__kmap_atomic_idx) - 1; -#ifdef CONFIG_DEBUG_HIGHMEM +# ifdef CONFIG_DEBUG_HIGHMEM WARN_ON_ONCE(in_irq() && !irqs_disabled()); BUG_ON(idx >= KM_TYPE_NR); -#endif +# endif return idx; +#else + current->kmap_idx++; + BUG_ON(current->kmap_idx > KM_TYPE_NR); + return current->kmap_idx - 1; +#endif } static inline int kmap_atomic_idx(void) { +#ifndef CONFIG_PREEMPT_RT_FULL return __this_cpu_read(__kmap_atomic_idx) - 1; +#else + return current->kmap_idx - 1; +#endif } static inline void kmap_atomic_idx_pop(void) { -#ifdef CONFIG_DEBUG_HIGHMEM +#ifndef CONFIG_PREEMPT_RT_FULL +# ifdef CONFIG_DEBUG_HIGHMEM int idx = __this_cpu_dec_return(__kmap_atomic_idx); BUG_ON(idx < 0); -#else +# else __this_cpu_dec(__kmap_atomic_idx); +# endif +#else + current->kmap_idx--; +# ifdef CONFIG_DEBUG_HIGHMEM + BUG_ON(current->kmap_idx < 0); +# endif #endif } @ include/linux/hrtimer.h:25 @ #include <linux/percpu.h> #include <linux/timer.h> #include <linux/timerqueue.h> +#include <linux/wait.h> struct hrtimer_clock_base; struct hrtimer_cpu_base; @ include/linux/hrtimer.h:45 @ enum hrtimer_mode { HRTIMER_MODE_REL = 0x01, HRTIMER_MODE_PINNED = 0x02, HRTIMER_MODE_SOFT = 0x04, + HRTIMER_MODE_HARD = 0x08, HRTIMER_MODE_ABS_PINNED = HRTIMER_MODE_ABS | HRTIMER_MODE_PINNED, HRTIMER_MODE_REL_PINNED = HRTIMER_MODE_REL | HRTIMER_MODE_PINNED, @ include/linux/hrtimer.h:56 @ enum hrtimer_mode { HRTIMER_MODE_ABS_PINNED_SOFT = HRTIMER_MODE_ABS_PINNED | HRTIMER_MODE_SOFT, HRTIMER_MODE_REL_PINNED_SOFT = HRTIMER_MODE_REL_PINNED | HRTIMER_MODE_SOFT, + HRTIMER_MODE_ABS_HARD = HRTIMER_MODE_ABS | HRTIMER_MODE_HARD, + HRTIMER_MODE_REL_HARD = HRTIMER_MODE_REL | HRTIMER_MODE_HARD, + + HRTIMER_MODE_ABS_PINNED_HARD = HRTIMER_MODE_ABS_PINNED | HRTIMER_MODE_HARD, + HRTIMER_MODE_REL_PINNED_HARD = HRTIMER_MODE_REL_PINNED | HRTIMER_MODE_HARD, }; /* @ include/linux/hrtimer.h:226 @ struct hrtimer_cpu_base { ktime_t expires_next; struct hrtimer *next_timer; ktime_t softirq_expires_next; +#ifdef CONFIG_PREEMPT_RT_BASE + wait_queue_head_t wait; +#endif struct hrtimer *softirq_next_timer; struct hrtimer_clock_base clock_base[HRTIMER_MAX_CLOCK_BASES]; } ____cacheline_aligned; @ include/linux/hrtimer.h:377 @ DECLARE_PER_CPU(struct tick_device, tick_cpu_device); /* Initialize timers: */ extern void hrtimer_init(struct hrtimer *timer, clockid_t which_clock, enum hrtimer_mode mode); +extern void hrtimer_init_sleeper(struct hrtimer_sleeper *sl, clockid_t clock_id, + enum hrtimer_mode mode, + struct task_struct *task); #ifdef CONFIG_DEBUG_OBJECTS_TIMERS extern void hrtimer_init_on_stack(struct hrtimer *timer, clockid_t which_clock, enum hrtimer_mode mode); +extern void hrtimer_init_sleeper_on_stack(struct hrtimer_sleeper *sl, + clockid_t clock_id, + enum hrtimer_mode mode, + struct task_struct *task); extern void destroy_hrtimer_on_stack(struct hrtimer *timer); #else @ include/linux/hrtimer.h:397 @ static inline void hrtimer_init_on_stack(struct hrtimer *timer, { hrtimer_init(timer, which_clock, mode); } + +static inline void hrtimer_init_sleeper_on_stack(struct hrtimer_sleeper *sl, + clockid_t clock_id, + enum hrtimer_mode mode, + struct task_struct *task) +{ + hrtimer_init_sleeper(sl, clock_id, mode, task); +} + static inline void destroy_hrtimer_on_stack(struct hrtimer *timer) { } #endif @ include/linux/hrtimer.h:446 @ static inline void hrtimer_restart(struct hrtimer *timer) hrtimer_start_expires(timer, HRTIMER_MODE_ABS); } +/* Softirq preemption could deadlock timer removal */ +#ifdef CONFIG_PREEMPT_RT_BASE + extern void hrtimer_wait_for_timer(const struct hrtimer *timer); +#else +# define hrtimer_wait_for_timer(timer) do { cpu_relax(); } while (0) +#endif + /* Query timers: */ extern ktime_t __hrtimer_get_remaining(const struct hrtimer *timer, bool adjust); @ include/linux/hrtimer.h:477 @ static inline int hrtimer_is_queued(struct hrtimer *timer) * Helper function to check, whether the timer is running the callback * function */ -static inline int hrtimer_callback_running(struct hrtimer *timer) +static inline int hrtimer_callback_running(const struct hrtimer *timer) { return timer->base->running == timer; } @ include/linux/hrtimer.h:515 @ extern long hrtimer_nanosleep(const struct timespec64 *rqtp, const enum hrtimer_mode mode, const clockid_t clockid); -extern void hrtimer_init_sleeper(struct hrtimer_sleeper *sl, - struct task_struct *tsk); - extern int schedule_hrtimeout_range(ktime_t *expires, u64 delta, const enum hrtimer_mode mode); extern int schedule_hrtimeout_range_clock(ktime_t *expires, @ include/linux/idr.h:159 @ static inline bool idr_is_empty(const struct idr *idr) * Each idr_preload() should be matched with an invocation of this * function. See idr_preload() for details. */ -static inline void idr_preload_end(void) -{ - preempt_enable(); -} +void idr_preload_end(void); /** * idr_for_each_entry() - Iterate over an IDR's elements of a given type. @ include/linux/interrupt.h:18 @ #include <linux/hrtimer.h> #include <linux/kref.h> #include <linux/workqueue.h> +#include <linux/swork.h> #include <linux/atomic.h> #include <asm/ptrace.h> @ include/linux/interrupt.h:67 @ * interrupt handler after suspending interrupts. For system * wakeup devices users need to implement wakeup detection in * their interrupt handlers. + * IRQF_NO_SOFTIRQ_CALL - Do not process softirqs in the irq thread context (RT) */ #define IRQF_SHARED 0x00000080 #define IRQF_PROBE_SHARED 0x00000100 @ include/linux/interrupt.h:81 @ #define IRQF_NO_THREAD 0x00010000 #define IRQF_EARLY_RESUME 0x00020000 #define IRQF_COND_SUSPEND 0x00040000 +#define IRQF_NO_SOFTIRQ_CALL 0x00080000 #define IRQF_TIMER (__IRQF_TIMER | IRQF_NO_SUSPEND | IRQF_NO_THREAD) @ include/linux/interrupt.h:233 @ extern void resume_device_irqs(void); * struct irq_affinity_notify - context for notification of IRQ affinity changes * @irq: Interrupt to which notification applies * @kref: Reference count, for internal use + * @swork: Swork item, for internal use * @work: Work item, for internal use * @notify: Function to be called on change. This will be * called in process context. @ include/linux/interrupt.h:245 @ extern void resume_device_irqs(void); struct irq_affinity_notify { unsigned int irq; struct kref kref; +#ifdef CONFIG_PREEMPT_RT_BASE + struct swork_event swork; +#else struct work_struct work; +#endif void (*notify)(struct irq_affinity_notify *, const cpumask_t *mask); void (*release)(struct kref *ref); }; @ include/linux/interrupt.h:440 @ extern int irq_set_irqchip_state(unsigned int irq, enum irqchip_irq_state which, bool state); #ifdef CONFIG_IRQ_FORCED_THREADING +# ifndef CONFIG_PREEMPT_RT_BASE extern bool force_irqthreads; +# else +# define force_irqthreads (true) +# endif #else -#define force_irqthreads (0) +#define force_irqthreads (false) #endif #ifndef __ARCH_SET_SOFTIRQ_PENDING @ include/linux/interrupt.h:503 @ struct softirq_action void (*action)(struct softirq_action *); }; +#ifndef CONFIG_PREEMPT_RT_FULL asmlinkage void do_softirq(void); asmlinkage void __do_softirq(void); - +static inline void thread_do_softirq(void) { do_softirq(); } #ifdef __ARCH_HAS_DO_SOFTIRQ void do_softirq_own_stack(void); #else @ include/linux/interrupt.h:515 @ static inline void do_softirq_own_stack(void) __do_softirq(); } #endif +#else +extern void thread_do_softirq(void); +#endif extern void open_softirq(int nr, void (*action)(struct softirq_action *)); extern void softirq_init(void); extern void __raise_softirq_irqoff(unsigned int nr); +#ifdef CONFIG_PREEMPT_RT_FULL +extern void __raise_softirq_irqoff_ksoft(unsigned int nr); +#else +static inline void __raise_softirq_irqoff_ksoft(unsigned int nr) +{ + __raise_softirq_irqoff(nr); +} +#endif extern void raise_softirq_irqoff(unsigned int nr); extern void raise_softirq(unsigned int nr); +extern void softirq_check_pending_idle(void); DECLARE_PER_CPU(struct task_struct *, ksoftirqd); @ include/linux/interrupt.h:555 @ static inline struct task_struct *this_cpu_ksoftirqd(void) to be executed on some cpu at least once after this. * If the tasklet is already scheduled, but its execution is still not started, it will be executed only once. - * If this tasklet is already running on another CPU (or schedule is called - from tasklet itself), it is rescheduled for later. + * If this tasklet is already running on another CPU, it is rescheduled + for later. + * Schedule must not be called from the tasklet itself (a lockup occurs) * Tasklet is strictly serialized wrt itself, but not wrt another tasklets. If client needs some intertask synchronization, he makes it with spinlocks. @ include/linux/interrupt.h:582 @ struct tasklet_struct name = { NULL, 0, ATOMIC_INIT(1), func, data } enum { TASKLET_STATE_SCHED, /* Tasklet is scheduled for execution */ - TASKLET_STATE_RUN /* Tasklet is running (SMP only) */ + TASKLET_STATE_RUN, /* Tasklet is running (SMP only) */ + TASKLET_STATE_PENDING /* Tasklet is pending */ }; -#ifdef CONFIG_SMP +#define TASKLET_STATEF_SCHED (1 << TASKLET_STATE_SCHED) +#define TASKLET_STATEF_RUN (1 << TASKLET_STATE_RUN) +#define TASKLET_STATEF_PENDING (1 << TASKLET_STATE_PENDING) + +#if defined(CONFIG_SMP) || defined(CONFIG_PREEMPT_RT_FULL) static inline int tasklet_trylock(struct tasklet_struct *t) { return !test_and_set_bit(TASKLET_STATE_RUN, &(t)->state); } +static inline int tasklet_tryunlock(struct tasklet_struct *t) +{ + return cmpxchg(&t->state, TASKLET_STATEF_RUN, 0) == TASKLET_STATEF_RUN; +} + static inline void tasklet_unlock(struct tasklet_struct *t) { smp_mb__before_atomic(); clear_bit(TASKLET_STATE_RUN, &(t)->state); } -static inline void tasklet_unlock_wait(struct tasklet_struct *t) -{ - while (test_bit(TASKLET_STATE_RUN, &(t)->state)) { barrier(); } -} +extern void tasklet_unlock_wait(struct tasklet_struct *t); + #else #define tasklet_trylock(t) 1 +#define tasklet_tryunlock(t) 1 #define tasklet_unlock_wait(t) do { } while (0) #define tasklet_unlock(t) do { } while (0) #endif @ include/linux/interrupt.h:645 @ static inline void tasklet_disable(struct tasklet_struct *t) smp_mb(); } -static inline void tasklet_enable(struct tasklet_struct *t) -{ - smp_mb__before_atomic(); - atomic_dec(&t->count); -} - +extern void tasklet_enable(struct tasklet_struct *t); extern void tasklet_kill(struct tasklet_struct *t); extern void tasklet_kill_immediate(struct tasklet_struct *t, unsigned int cpu); extern void tasklet_init(struct tasklet_struct *t, void (*func)(unsigned long), unsigned long data); +#ifdef CONFIG_PREEMPT_RT_FULL +extern void softirq_early_init(void); +#else +static inline void softirq_early_init(void) { } +#endif + struct tasklet_hrtimer { struct hrtimer timer; struct tasklet_struct tasklet; @ include/linux/irq.h:77 @ enum irqchip_irq_state; * IRQ_IS_POLLED - Always polled by another interrupt. Exclude * it from the spurious interrupt detection * mechanism and from core side polling. + * IRQ_NO_SOFTIRQ_CALL - No softirq processing in the irq thread context (RT) * IRQ_DISABLE_UNLAZY - Disable lazy irq disable */ enum { @ include/linux/irq.h:105 @ enum { IRQ_PER_CPU_DEVID = (1 << 17), IRQ_IS_POLLED = (1 << 18), IRQ_DISABLE_UNLAZY = (1 << 19), + IRQ_NO_SOFTIRQ_CALL = (1 << 20), }; #define IRQF_MODIFY_MASK \ (IRQ_TYPE_SENSE_MASK | IRQ_NOPROBE | IRQ_NOREQUEST | \ IRQ_NOAUTOEN | IRQ_MOVE_PCNTXT | IRQ_LEVEL | IRQ_NO_BALANCING | \ IRQ_PER_CPU | IRQ_NESTED_THREAD | IRQ_NOTHREAD | IRQ_PER_CPU_DEVID | \ - IRQ_IS_POLLED | IRQ_DISABLE_UNLAZY) + IRQ_IS_POLLED | IRQ_DISABLE_UNLAZY | IRQ_NO_SOFTIRQ_CALL) #define IRQ_NO_BALANCING_MASK (IRQ_PER_CPU | IRQ_NO_BALANCING) @ include/linux/irq_work.h:21 @ /* Doesn't want IPI, wait for tick: */ #define IRQ_WORK_LAZY BIT(2) +/* Run hard IRQ context, even on RT */ +#define IRQ_WORK_HARD_IRQ BIT(3) #define IRQ_WORK_CLAIMED (IRQ_WORK_PENDING | IRQ_WORK_BUSY) @ include/linux/irq_work.h:57 @ static inline bool irq_work_needs_cpu(void) { return false; } static inline void irq_work_run(void) { } #endif +#if defined(CONFIG_IRQ_WORK) && defined(CONFIG_PREEMPT_RT_FULL) +void irq_work_tick_soft(void); +#else +static inline void irq_work_tick_soft(void) { } +#endif + #endif /* _LINUX_IRQ_WORK_H */ @ include/linux/irqdesc.h:73 @ struct irq_desc { unsigned int irqs_unhandled; atomic_t threads_handled; int threads_handled_last; + u64 random_ip; raw_spinlock_t lock; struct cpumask *percpu_enabled; const struct cpumask *percpu_affinity; @ include/linux/irqflags.h:35 @ do { \ do { \ current->hardirq_context--; \ } while (0) -# define lockdep_softirq_enter() \ -do { \ - current->softirq_context++; \ -} while (0) -# define lockdep_softirq_exit() \ -do { \ - current->softirq_context--; \ -} while (0) #else # define trace_hardirqs_on() do { } while (0) # define trace_hardirqs_off() do { } while (0) @ include/linux/irqflags.h:50 @ do { \ # define lockdep_softirq_exit() do { } while (0) #endif +#if defined(CONFIG_TRACE_IRQFLAGS) && !defined(CONFIG_PREEMPT_RT_FULL) +# define lockdep_softirq_enter() \ +do { \ + current->softirq_context++; \ +} while (0) +# define lockdep_softirq_exit() \ +do { \ + current->softirq_context--; \ +} while (0) + +#else +# define lockdep_softirq_enter() do { } while (0) +# define lockdep_softirq_exit() do { } while (0) +#endif + #if defined(CONFIG_IRQSOFF_TRACER) || \ defined(CONFIG_PREEMPT_TRACER) extern void stop_critical_timings(void); @ include/linux/jbd2.h:350 @ static inline struct journal_head *bh2jh(struct buffer_head *bh) static inline void jbd_lock_bh_state(struct buffer_head *bh) { +#ifndef CONFIG_PREEMPT_RT_BASE bit_spin_lock(BH_State, &bh->b_state); +#else + spin_lock(&bh->b_state_lock); +#endif } static inline int jbd_trylock_bh_state(struct buffer_head *bh) { +#ifndef CONFIG_PREEMPT_RT_BASE return bit_spin_trylock(BH_State, &bh->b_state); +#else + return spin_trylock(&bh->b_state_lock); +#endif } static inline int jbd_is_locked_bh_state(struct buffer_head *bh) { +#ifndef CONFIG_PREEMPT_RT_BASE return bit_spin_is_locked(BH_State, &bh->b_state); +#else + return spin_is_locked(&bh->b_state_lock); +#endif } static inline void jbd_unlock_bh_state(struct buffer_head *bh) { +#ifndef CONFIG_PREEMPT_RT_BASE bit_spin_unlock(BH_State, &bh->b_state); +#else + spin_unlock(&bh->b_state_lock); +#endif } static inline void jbd_lock_bh_journal_head(struct buffer_head *bh) { +#ifndef CONFIG_PREEMPT_RT_BASE bit_spin_lock(BH_JournalHead, &bh->b_state); +#else + spin_lock(&bh->b_journal_head_lock); +#endif } static inline void jbd_unlock_bh_journal_head(struct buffer_head *bh) { +#ifndef CONFIG_PREEMPT_RT_BASE bit_spin_unlock(BH_JournalHead, &bh->b_state); +#else + spin_unlock(&bh->b_journal_head_lock); +#endif } #define J_ASSERT(assert) BUG_ON(!(assert)) @ include/linux/kdb.h:170 @ extern __printf(2, 0) int vkdb_printf(enum kdb_msgsrc src, const char *fmt, extern __printf(1, 2) int kdb_printf(const char *, ...); typedef __printf(1, 2) int (*kdb_printf_t)(const char *, ...); +#define in_kdb_printk() (kdb_trap_printk) extern void kdb_init(int level); /* Access to kdb specific polling devices */ @ include/linux/kdb.h:205 @ extern int kdb_register_flags(char *, kdb_func_t, char *, char *, extern int kdb_unregister(char *); #else /* ! CONFIG_KGDB_KDB */ static inline __printf(1, 2) int kdb_printf(const char *fmt, ...) { return 0; } +#define in_kdb_printk() (0) static inline void kdb_init(int level) {} static inline int kdb_register(char *cmd, kdb_func_t func, char *usage, char *help, short minlen) { return 0; } @ include/linux/kernel.h:228 @ extern int _cond_resched(void); */ # define might_sleep() \ do { __might_sleep(__FILE__, __LINE__, 0); might_resched(); } while (0) + +# define might_sleep_no_state_check() \ + do { ___might_sleep(__FILE__, __LINE__, 0); might_resched(); } while (0) # define sched_annotate_sleep() (current->task_state_change = 0) #else static inline void ___might_sleep(const char *file, int line, @ include/linux/kernel.h:238 @ extern int _cond_resched(void); static inline void __might_sleep(const char *file, int line, int preempt_offset) { } # define might_sleep() do { might_resched(); } while (0) +# define might_sleep_no_state_check() do { might_resched(); } while (0) # define sched_annotate_sleep() do { } while (0) #endif @ include/linux/kernel.h:539 @ extern enum system_states { SYSTEM_HALT, SYSTEM_POWER_OFF, SYSTEM_RESTART, + SYSTEM_SUSPEND, } system_state; #define TAINT_PROPRIETARY_MODULE 0 @ include/linux/libata.h:1834 @ extern unsigned int ata_sff_data_xfer(struct ata_queued_cmd *qc, unsigned char *buf, unsigned int buflen, int rw); extern unsigned int ata_sff_data_xfer32(struct ata_queued_cmd *qc, unsigned char *buf, unsigned int buflen, int rw); -extern unsigned int ata_sff_data_xfer_noirq(struct ata_queued_cmd *qc, - unsigned char *buf, unsigned int buflen, int rw); extern void ata_sff_irq_on(struct ata_port *ap); extern void ata_sff_irq_clear(struct ata_port *ap); extern int ata_sff_hsm_move(struct ata_port *ap, struct ata_queued_cmd *qc, @ include/linux/list_bl.h:6 @ #define _LINUX_LIST_BL_H #include <linux/list.h> +#include <linux/spinlock.h> #include <linux/bit_spinlock.h> /* @ include/linux/list_bl.h:37 @ struct hlist_bl_head { struct hlist_bl_node *first; +#ifdef CONFIG_PREEMPT_RT_BASE + raw_spinlock_t lock; +#endif }; struct hlist_bl_node { struct hlist_bl_node *next, **pprev; }; -#define INIT_HLIST_BL_HEAD(ptr) \ - ((ptr)->first = NULL) + +#ifdef CONFIG_PREEMPT_RT_BASE +#define INIT_HLIST_BL_HEAD(h) \ +do { \ + (h)->first = NULL; \ + raw_spin_lock_init(&(h)->lock); \ +} while (0) +#else +#define INIT_HLIST_BL_HEAD(h) (h)->first = NULL +#endif static inline void INIT_HLIST_BL_NODE(struct hlist_bl_node *h) { @ include/linux/list_bl.h:134 @ static inline void hlist_bl_del_init(struct hlist_bl_node *n) static inline void hlist_bl_lock(struct hlist_bl_head *b) { +#ifndef CONFIG_PREEMPT_RT_BASE bit_spin_lock(0, (unsigned long *)b); +#else + raw_spin_lock(&b->lock); +#if defined(CONFIG_SMP) || defined(CONFIG_DEBUG_SPINLOCK) + __set_bit(0, (unsigned long *)b); +#endif +#endif } static inline void hlist_bl_unlock(struct hlist_bl_head *b) { +#ifndef CONFIG_PREEMPT_RT_BASE __bit_spin_unlock(0, (unsigned long *)b); +#else +#if defined(CONFIG_SMP) || defined(CONFIG_DEBUG_SPINLOCK) + __clear_bit(0, (unsigned long *)b); +#endif + raw_spin_unlock(&b->lock); +#endif } static inline bool hlist_bl_is_locked(struct hlist_bl_head *b) @ include/linux/locallock.h:4 @ +#ifndef _LINUX_LOCALLOCK_H +#define _LINUX_LOCALLOCK_H + +#include <linux/percpu.h> +#include <linux/spinlock.h> + +#ifdef CONFIG_PREEMPT_RT_BASE + +#ifdef CONFIG_DEBUG_SPINLOCK +# define LL_WARN(cond) WARN_ON(cond) +#else +# define LL_WARN(cond) do { } while (0) +#endif + +/* + * per cpu lock based substitute for local_irq_*() + */ +struct local_irq_lock { + spinlock_t lock; + struct task_struct *owner; + int nestcnt; + unsigned long flags; +}; + +#define DEFINE_LOCAL_IRQ_LOCK(lvar) \ + DEFINE_PER_CPU(struct local_irq_lock, lvar) = { \ + .lock = __SPIN_LOCK_UNLOCKED((lvar).lock) } + +#define DECLARE_LOCAL_IRQ_LOCK(lvar) \ + DECLARE_PER_CPU(struct local_irq_lock, lvar) + +#define local_irq_lock_init(lvar) \ + do { \ + int __cpu; \ + for_each_possible_cpu(__cpu) \ + spin_lock_init(&per_cpu(lvar, __cpu).lock); \ + } while (0) + +static inline void __local_lock(struct local_irq_lock *lv) +{ + if (lv->owner != current) { + spin_lock(&lv->lock); + LL_WARN(lv->owner); + LL_WARN(lv->nestcnt); + lv->owner = current; + } + lv->nestcnt++; +} + +#define local_lock(lvar) \ + do { __local_lock(&get_local_var(lvar)); } while (0) + +#define local_lock_on(lvar, cpu) \ + do { __local_lock(&per_cpu(lvar, cpu)); } while (0) + +static inline int __local_trylock(struct local_irq_lock *lv) +{ + if (lv->owner != current && spin_trylock(&lv->lock)) { + LL_WARN(lv->owner); + LL_WARN(lv->nestcnt); + lv->owner = current; + lv->nestcnt = 1; + return 1; + } else if (lv->owner == current) { + lv->nestcnt++; + return 1; + } + return 0; +} + +#define local_trylock(lvar) \ + ({ \ + int __locked; \ + __locked = __local_trylock(&get_local_var(lvar)); \ + if (!__locked) \ + put_local_var(lvar); \ + __locked; \ + }) + +static inline void __local_unlock(struct local_irq_lock *lv) +{ + LL_WARN(lv->nestcnt == 0); + LL_WARN(lv->owner != current); + if (--lv->nestcnt) + return; + + lv->owner = NULL; + spin_unlock(&lv->lock); +} + +#define local_unlock(lvar) \ + do { \ + __local_unlock(this_cpu_ptr(&lvar)); \ + put_local_var(lvar); \ + } while (0) + +#define local_unlock_on(lvar, cpu) \ + do { __local_unlock(&per_cpu(lvar, cpu)); } while (0) + +static inline void __local_lock_irq(struct local_irq_lock *lv) +{ + spin_lock_irqsave(&lv->lock, lv->flags); + LL_WARN(lv->owner); + LL_WARN(lv->nestcnt); + lv->owner = current; + lv->nestcnt = 1; +} + +#define local_lock_irq(lvar) \ + do { __local_lock_irq(&get_local_var(lvar)); } while (0) + +#define local_lock_irq_on(lvar, cpu) \ + do { __local_lock_irq(&per_cpu(lvar, cpu)); } while (0) + +static inline void __local_unlock_irq(struct local_irq_lock *lv) +{ + LL_WARN(!lv->nestcnt); + LL_WARN(lv->owner != current); + lv->owner = NULL; + lv->nestcnt = 0; + spin_unlock_irq(&lv->lock); +} + +#define local_unlock_irq(lvar) \ + do { \ + __local_unlock_irq(this_cpu_ptr(&lvar)); \ + put_local_var(lvar); \ + } while (0) + +#define local_unlock_irq_on(lvar, cpu) \ + do { \ + __local_unlock_irq(&per_cpu(lvar, cpu)); \ + } while (0) + +static inline int __local_lock_irqsave(struct local_irq_lock *lv) +{ + if (lv->owner != current) { + __local_lock_irq(lv); + return 0; + } else { + lv->nestcnt++; + return 1; + } +} + +#define local_lock_irqsave(lvar, _flags) \ + do { \ + if (__local_lock_irqsave(&get_local_var(lvar))) \ + put_local_var(lvar); \ + _flags = __this_cpu_read(lvar.flags); \ + } while (0) + +#define local_lock_irqsave_on(lvar, _flags, cpu) \ + do { \ + __local_lock_irqsave(&per_cpu(lvar, cpu)); \ + _flags = per_cpu(lvar, cpu).flags; \ + } while (0) + +static inline int __local_unlock_irqrestore(struct local_irq_lock *lv, + unsigned long flags) +{ + LL_WARN(!lv->nestcnt); + LL_WARN(lv->owner != current); + if (--lv->nestcnt) + return 0; + + lv->owner = NULL; + spin_unlock_irqrestore(&lv->lock, lv->flags); + return 1; +} + +#define local_unlock_irqrestore(lvar, flags) \ + do { \ + if (__local_unlock_irqrestore(this_cpu_ptr(&lvar), flags)) \ + put_local_var(lvar); \ + } while (0) + +#define local_unlock_irqrestore_on(lvar, flags, cpu) \ + do { \ + __local_unlock_irqrestore(&per_cpu(lvar, cpu), flags); \ + } while (0) + +#define local_spin_trylock_irq(lvar, lock) \ + ({ \ + int __locked; \ + local_lock_irq(lvar); \ + __locked = spin_trylock(lock); \ + if (!__locked) \ + local_unlock_irq(lvar); \ + __locked; \ + }) + +#define local_spin_lock_irq(lvar, lock) \ + do { \ + local_lock_irq(lvar); \ + spin_lock(lock); \ + } while (0) + +#define local_spin_unlock_irq(lvar, lock) \ + do { \ + spin_unlock(lock); \ + local_unlock_irq(lvar); \ + } while (0) + +#define local_spin_lock_irqsave(lvar, lock, flags) \ + do { \ + local_lock_irqsave(lvar, flags); \ + spin_lock(lock); \ + } while (0) + +#define local_spin_unlock_irqrestore(lvar, lock, flags) \ + do { \ + spin_unlock(lock); \ + local_unlock_irqrestore(lvar, flags); \ + } while (0) + +#define get_locked_var(lvar, var) \ + (*({ \ + local_lock(lvar); \ + this_cpu_ptr(&var); \ + })) + +#define put_locked_var(lvar, var) local_unlock(lvar); + +#define get_locked_ptr(lvar, var) \ + ({ \ + local_lock(lvar); \ + this_cpu_ptr(var); \ + }) + +#define put_locked_ptr(lvar, var) local_unlock(lvar); + +#define local_lock_cpu(lvar) \ + ({ \ + local_lock(lvar); \ + smp_processor_id(); \ + }) + +#define local_unlock_cpu(lvar) local_unlock(lvar) + +#else /* PREEMPT_RT_BASE */ + +#define DEFINE_LOCAL_IRQ_LOCK(lvar) __typeof__(const int) lvar +#define DECLARE_LOCAL_IRQ_LOCK(lvar) extern __typeof__(const int) lvar + +static inline void local_irq_lock_init(int lvar) { } + +#define local_trylock(lvar) \ + ({ \ + preempt_disable(); \ + 1; \ + }) + +#define local_lock(lvar) preempt_disable() +#define local_unlock(lvar) preempt_enable() +#define local_lock_irq(lvar) local_irq_disable() +#define local_lock_irq_on(lvar, cpu) local_irq_disable() +#define local_unlock_irq(lvar) local_irq_enable() +#define local_unlock_irq_on(lvar, cpu) local_irq_enable() +#define local_lock_irqsave(lvar, flags) local_irq_save(flags) +#define local_unlock_irqrestore(lvar, flags) local_irq_restore(flags) + +#define local_spin_trylock_irq(lvar, lock) spin_trylock_irq(lock) +#define local_spin_lock_irq(lvar, lock) spin_lock_irq(lock) +#define local_spin_unlock_irq(lvar, lock) spin_unlock_irq(lock) +#define local_spin_lock_irqsave(lvar, lock, flags) \ + spin_lock_irqsave(lock, flags) +#define local_spin_unlock_irqrestore(lvar, lock, flags) \ + spin_unlock_irqrestore(lock, flags) + +#define get_locked_var(lvar, var) get_cpu_var(var) +#define put_locked_var(lvar, var) put_cpu_var(var) +#define get_locked_ptr(lvar, var) get_cpu_ptr(var) +#define put_locked_ptr(lvar, var) put_cpu_ptr(var) + +#define local_lock_cpu(lvar) get_cpu() +#define local_unlock_cpu(lvar) put_cpu() + +#endif + +#endif @ include/linux/mm_types.h:15 @ #include <linux/completion.h> #include <linux/cpumask.h> #include <linux/uprobes.h> +#include <linux/rcupdate.h> #include <linux/page-flags-layout.h> #include <linux/workqueue.h> @ include/linux/mm_types.h:495 @ struct mm_struct { bool tlb_flush_batched; #endif struct uprobes_state uprobes_state; +#ifdef CONFIG_PREEMPT_RT_BASE + struct rcu_head delayed_drop; +#endif #ifdef CONFIG_HUGETLB_PAGE atomic_long_t hugetlb_usage; #endif @ include/linux/mutex.h:26 @ struct ww_acquire_ctx; +#ifdef CONFIG_DEBUG_LOCK_ALLOC +# define __DEP_MAP_MUTEX_INITIALIZER(lockname) \ + , .dep_map = { .name = #lockname } +#else +# define __DEP_MAP_MUTEX_INITIALIZER(lockname) +#endif + +#ifdef CONFIG_PREEMPT_RT_FULL +# include <linux/mutex_rt.h> +#else + /* * Simple, straightforward mutexes with strict semantics: * @ include/linux/mutex.h:133 @ do { \ __mutex_init((mutex), #mutex, &__key); \ } while (0) -#ifdef CONFIG_DEBUG_LOCK_ALLOC -# define __DEP_MAP_MUTEX_INITIALIZER(lockname) \ - , .dep_map = { .name = #lockname } -#else -# define __DEP_MAP_MUTEX_INITIALIZER(lockname) -#endif - #define __MUTEX_INITIALIZER(lockname) \ { .owner = ATOMIC_LONG_INIT(0) \ , .wait_lock = __SPIN_LOCK_UNLOCKED(lockname.wait_lock) \ @ include/linux/mutex.h:240 @ mutex_trylock_recursive(struct mutex *lock) return mutex_trylock(lock); } +#endif /* !PREEMPT_RT_FULL */ + #endif /* __LINUX_MUTEX_H */ @ include/linux/mutex_rt.h:4 @ +#ifndef __LINUX_MUTEX_RT_H +#define __LINUX_MUTEX_RT_H + +#ifndef __LINUX_MUTEX_H +#error "Please include mutex.h" +#endif + +#include <linux/rtmutex.h> + +/* FIXME: Just for __lockfunc */ +#include <linux/spinlock.h> + +struct mutex { + struct rt_mutex lock; +#ifdef CONFIG_DEBUG_LOCK_ALLOC + struct lockdep_map dep_map; +#endif +}; + +#define __MUTEX_INITIALIZER(mutexname) \ + { \ + .lock = __RT_MUTEX_INITIALIZER(mutexname.lock) \ + __DEP_MAP_MUTEX_INITIALIZER(mutexname) \ + } + +#define DEFINE_MUTEX(mutexname) \ + struct mutex mutexname = __MUTEX_INITIALIZER(mutexname) + +extern void __mutex_do_init(struct mutex *lock, const char *name, struct lock_class_key *key); +extern void __lockfunc _mutex_lock(struct mutex *lock); +extern void __lockfunc _mutex_lock_io(struct mutex *lock); +extern void __lockfunc _mutex_lock_io_nested(struct mutex *lock, int subclass); +extern int __lockfunc _mutex_lock_interruptible(struct mutex *lock); +extern int __lockfunc _mutex_lock_killable(struct mutex *lock); +extern void __lockfunc _mutex_lock_nested(struct mutex *lock, int subclass); +extern void __lockfunc _mutex_lock_nest_lock(struct mutex *lock, struct lockdep_map *nest_lock); +extern int __lockfunc _mutex_lock_interruptible_nested(struct mutex *lock, int subclass); +extern int __lockfunc _mutex_lock_killable_nested(struct mutex *lock, int subclass); +extern int __lockfunc _mutex_trylock(struct mutex *lock); +extern void __lockfunc _mutex_unlock(struct mutex *lock); + +#define mutex_is_locked(l) rt_mutex_is_locked(&(l)->lock) +#define mutex_lock(l) _mutex_lock(l) +#define mutex_lock_interruptible(l) _mutex_lock_interruptible(l) +#define mutex_lock_killable(l) _mutex_lock_killable(l) +#define mutex_trylock(l) _mutex_trylock(l) +#define mutex_unlock(l) _mutex_unlock(l) +#define mutex_lock_io(l) _mutex_lock_io(l); + +#define __mutex_owner(l) ((l)->lock.owner) + +#ifdef CONFIG_DEBUG_MUTEXES +#define mutex_destroy(l) rt_mutex_destroy(&(l)->lock) +#else +static inline void mutex_destroy(struct mutex *lock) {} +#endif + +#ifdef CONFIG_DEBUG_LOCK_ALLOC +# define mutex_lock_nested(l, s) _mutex_lock_nested(l, s) +# define mutex_lock_interruptible_nested(l, s) \ + _mutex_lock_interruptible_nested(l, s) +# define mutex_lock_killable_nested(l, s) \ + _mutex_lock_killable_nested(l, s) +# define mutex_lock_io_nested(l, s) _mutex_lock_io_nested(l, s) + +# define mutex_lock_nest_lock(lock, nest_lock) \ +do { \ + typecheck(struct lockdep_map *, &(nest_lock)->dep_map); \ + _mutex_lock_nest_lock(lock, &(nest_lock)->dep_map); \ +} while (0) + +#else +# define mutex_lock_nested(l, s) _mutex_lock(l) +# define mutex_lock_interruptible_nested(l, s) \ + _mutex_lock_interruptible(l) +# define mutex_lock_killable_nested(l, s) \ + _mutex_lock_killable(l) +# define mutex_lock_nest_lock(lock, nest_lock) mutex_lock(lock) +# define mutex_lock_io_nested(l, s) _mutex_lock_io(l) +#endif + +# define mutex_init(mutex) \ +do { \ + static struct lock_class_key __key; \ + \ + rt_mutex_init(&(mutex)->lock); \ + __mutex_do_init((mutex), #mutex, &__key); \ +} while (0) + +# define __mutex_init(mutex, name, key) \ +do { \ + rt_mutex_init(&(mutex)->lock); \ + __mutex_do_init((mutex), name, key); \ +} while (0) + +/** + * These values are chosen such that FAIL and SUCCESS match the + * values of the regular mutex_trylock(). + */ +enum mutex_trylock_recursive_enum { + MUTEX_TRYLOCK_FAILED = 0, + MUTEX_TRYLOCK_SUCCESS = 1, + MUTEX_TRYLOCK_RECURSIVE, +}; +/** + * mutex_trylock_recursive - trylock variant that allows recursive locking + * @lock: mutex to be locked + * + * This function should not be used, _ever_. It is purely for hysterical GEM + * raisins, and once those are gone this will be removed. + * + * Returns: + * MUTEX_TRYLOCK_FAILED - trylock failed, + * MUTEX_TRYLOCK_SUCCESS - lock acquired, + * MUTEX_TRYLOCK_RECURSIVE - we already owned the lock. + */ +int __rt_mutex_owner_current(struct rt_mutex *lock); + +static inline /* __deprecated */ __must_check enum mutex_trylock_recursive_enum +mutex_trylock_recursive(struct mutex *lock) +{ + if (unlikely(__rt_mutex_owner_current(&lock->lock))) + return MUTEX_TRYLOCK_RECURSIVE; + + return mutex_trylock(lock); +} + +extern int atomic_dec_and_mutex_lock(atomic_t *cnt, struct mutex *lock); + +#endif @ include/linux/netdevice.h:413 @ typedef enum rx_handler_result rx_handler_result_t; typedef rx_handler_result_t rx_handler_func_t(struct sk_buff **pskb); void __napi_schedule(struct napi_struct *n); + +/* + * When PREEMPT_RT_FULL is defined, all device interrupt handlers + * run as threads, and they can also be preempted (without PREEMPT_RT + * interrupt threads can not be preempted). Which means that calling + * __napi_schedule_irqoff() from an interrupt handler can be preempted + * and can corrupt the napi->poll_list. + */ +#ifdef CONFIG_PREEMPT_RT_FULL +#define __napi_schedule_irqoff(n) __napi_schedule(n) +#else void __napi_schedule_irqoff(struct napi_struct *n); +#endif static inline bool napi_disable_pending(struct napi_struct *n) { @ include/linux/netdevice.h:587 @ struct netdev_queue { * write-mostly part */ spinlock_t _xmit_lock ____cacheline_aligned_in_smp; +#ifdef CONFIG_PREEMPT_RT_FULL + struct task_struct *xmit_lock_owner; +#else int xmit_lock_owner; +#endif /* * Time (in jiffies) of last Tx */ @ include/linux/netdevice.h:2498 @ void netdev_freemem(struct net_device *dev); void synchronize_net(void); int init_dummy_netdev(struct net_device *dev); -DECLARE_PER_CPU(int, xmit_recursion); #define XMIT_RECURSION_LIMIT 10 +#ifdef CONFIG_PREEMPT_RT_FULL +static inline int dev_recursion_level(void) +{ + return current->xmit_recursion; +} + +static inline int xmit_rec_read(void) +{ + return current->xmit_recursion; +} + +static inline void xmit_rec_inc(void) +{ + current->xmit_recursion++; +} + +static inline void xmit_rec_dec(void) +{ + current->xmit_recursion--; +} + +#else + +DECLARE_PER_CPU(int, xmit_recursion); static inline int dev_recursion_level(void) { return this_cpu_read(xmit_recursion); } +static inline int xmit_rec_read(void) +{ + return __this_cpu_read(xmit_recursion); +} + +static inline void xmit_rec_inc(void) +{ + __this_cpu_inc(xmit_recursion); +} + +static inline void xmit_rec_dec(void) +{ + __this_cpu_dec(xmit_recursion); +} +#endif + struct net_device *dev_get_by_index(struct net *net, int ifindex); struct net_device *__dev_get_by_index(struct net *net, int ifindex); struct net_device *dev_get_by_index_rcu(struct net *net, int ifindex); @ include/linux/netdevice.h:2879 @ struct softnet_data { unsigned int dropped; struct sk_buff_head input_pkt_queue; struct napi_struct backlog; + struct sk_buff_head tofree_queue; }; @ include/linux/netdevice.h:3615 @ static inline u32 netif_msg_init(int debug_value, int default_msg_enable_bits) return (1 << debug_value) - 1; } +#ifdef CONFIG_PREEMPT_RT_FULL +static inline void netdev_queue_set_owner(struct netdev_queue *txq, int cpu) +{ + txq->xmit_lock_owner = current; +} + +static inline void netdev_queue_clear_owner(struct netdev_queue *txq) +{ + txq->xmit_lock_owner = NULL; +} + +static inline bool netdev_queue_has_owner(struct netdev_queue *txq) +{ + if (txq->xmit_lock_owner != NULL) + return true; + return false; +} + +#else + +static inline void netdev_queue_set_owner(struct netdev_queue *txq, int cpu) +{ + txq->xmit_lock_owner = cpu; +} + +static inline void netdev_queue_clear_owner(struct netdev_queue *txq) +{ + txq->xmit_lock_owner = -1; +} + +static inline bool netdev_queue_has_owner(struct netdev_queue *txq) +{ + if (txq->xmit_lock_owner != -1) + return true; + return false; +} +#endif + static inline void __netif_tx_lock(struct netdev_queue *txq, int cpu) { spin_lock(&txq->_xmit_lock); - txq->xmit_lock_owner = cpu; + netdev_queue_set_owner(txq, cpu); } static inline bool __netif_tx_acquire(struct netdev_queue *txq) @ include/linux/netdevice.h:3673 @ static inline void __netif_tx_release(struct netdev_queue *txq) static inline void __netif_tx_lock_bh(struct netdev_queue *txq) { spin_lock_bh(&txq->_xmit_lock); - txq->xmit_lock_owner = smp_processor_id(); + netdev_queue_set_owner(txq, smp_processor_id()); } static inline bool __netif_tx_trylock(struct netdev_queue *txq) { bool ok = spin_trylock(&txq->_xmit_lock); if (likely(ok)) - txq->xmit_lock_owner = smp_processor_id(); + netdev_queue_set_owner(txq, smp_processor_id()); return ok; } static inline void __netif_tx_unlock(struct netdev_queue *txq) { - txq->xmit_lock_owner = -1; + netdev_queue_clear_owner(txq); spin_unlock(&txq->_xmit_lock); } static inline void __netif_tx_unlock_bh(struct netdev_queue *txq) { - txq->xmit_lock_owner = -1; + netdev_queue_clear_owner(txq); spin_unlock_bh(&txq->_xmit_lock); } static inline void txq_trans_update(struct netdev_queue *txq) { - if (txq->xmit_lock_owner != -1) + if (netdev_queue_has_owner(txq)) txq->trans_start = jiffies; } @ include/linux/netfilter/x_tables.h:9 @ #include <linux/netdevice.h> #include <linux/static_key.h> #include <linux/netfilter.h> +#include <linux/locallock.h> #include <uapi/linux/netfilter/x_tables.h> /* Test a struct->invflags and a boolean for inequality */ @ include/linux/netfilter/x_tables.h:347 @ void xt_free_table_info(struct xt_table_info *info); */ DECLARE_PER_CPU(seqcount_t, xt_recseq); +DECLARE_LOCAL_IRQ_LOCK(xt_write_lock); + /* xt_tee_enabled - true if x_tables needs to handle reentrancy * * Enabled if current ip(6)tables ruleset has at least one -j TEE rule. @ include/linux/netfilter/x_tables.h:369 @ static inline unsigned int xt_write_recseq_begin(void) { unsigned int addend; + /* RT protection */ + local_lock(xt_write_lock); + /* * Low order bit of sequence is set if we already * called xt_write_recseq_begin(). @ include/linux/netfilter/x_tables.h:402 @ static inline void xt_write_recseq_end(unsigned int addend) /* this is kind of a write_seqcount_end(), but addend is 0 or 1 */ smp_wmb(); __this_cpu_add(xt_recseq.sequence, addend); + local_unlock(xt_write_lock); } /* @ include/linux/nfs_fs.h:166 @ struct nfs_inode { /* Readers: in-flight sillydelete RPC calls */ /* Writers: rmdir */ +#ifdef CONFIG_PREEMPT_RT_BASE + struct semaphore rmdir_sem; +#else struct rw_semaphore rmdir_sem; +#endif struct mutex commit_mutex; #if IS_ENABLED(CONFIG_NFS_V4) @ include/linux/nfs_xdr.h:1533 @ struct nfs_unlinkdata { struct nfs_removeargs args; struct nfs_removeres res; struct dentry *dentry; - wait_queue_head_t wq; + struct swait_queue_head wq; struct rpc_cred *cred; struct nfs_fattr dir_attr; long timeout; @ include/linux/notifier.h:10 @ * * Alan Cox <Alan.Cox@linux.org> */ - + #ifndef _LINUX_NOTIFIER_H #define _LINUX_NOTIFIER_H #include <linux/errno.h> @ include/linux/notifier.h:46 @ * in srcu_notifier_call_chain(): no cache bounces and no memory barriers. * As compensation, srcu_notifier_chain_unregister() is rather expensive. * SRCU notifier chains should be used when the chain will be called very - * often but notifier_blocks will seldom be removed. Also, SRCU notifier - * chains are slightly more difficult to use because they require special - * runtime initialization. + * often but notifier_blocks will seldom be removed. */ struct notifier_block; @ include/linux/notifier.h:92 @ struct srcu_notifier_head { (name)->head = NULL; \ } while (0) -/* srcu_notifier_heads must be initialized and cleaned up dynamically */ +/* srcu_notifier_heads must be cleaned up dynamically */ extern void srcu_init_notifier_head(struct srcu_notifier_head *nh); #define srcu_cleanup_notifier_head(name) \ cleanup_srcu_struct(&(name)->srcu); @ include/linux/notifier.h:105 @ extern void srcu_init_notifier_head(struct srcu_notifier_head *nh); .head = NULL } #define RAW_NOTIFIER_INIT(name) { \ .head = NULL } -/* srcu_notifier_heads cannot be initialized statically */ + +#define SRCU_NOTIFIER_INIT(name, pcpu) \ + { \ + .mutex = __MUTEX_INITIALIZER(name.mutex), \ + .head = NULL, \ + .srcu = __SRCU_STRUCT_INIT(name.srcu, pcpu), \ + } #define ATOMIC_NOTIFIER_HEAD(name) \ struct atomic_notifier_head name = \ @ include/linux/notifier.h:123 @ extern void srcu_init_notifier_head(struct srcu_notifier_head *nh); struct raw_notifier_head name = \ RAW_NOTIFIER_INIT(name) +#ifdef CONFIG_TREE_SRCU +#define _SRCU_NOTIFIER_HEAD(name, mod) \ + static DEFINE_PER_CPU(struct srcu_data, \ + name##_head_srcu_data); \ + mod struct srcu_notifier_head name = \ + SRCU_NOTIFIER_INIT(name, name##_head_srcu_data) + +#else +#define _SRCU_NOTIFIER_HEAD(name, mod) \ + mod struct srcu_notifier_head name = \ + SRCU_NOTIFIER_INIT(name, name) + +#endif + +#define SRCU_NOTIFIER_HEAD(name) \ + _SRCU_NOTIFIER_HEAD(name, ) + +#define SRCU_NOTIFIER_HEAD_STATIC(name) \ + _SRCU_NOTIFIER_HEAD(name, static) + #ifdef __KERNEL__ extern int atomic_notifier_chain_register(struct atomic_notifier_head *nh, @ include/linux/notifier.h:212 @ static inline int notifier_to_errno(int ret) /* * Declared notifiers so far. I can imagine quite a few more chains - * over time (eg laptop power reset chains, reboot chain (to clean + * over time (eg laptop power reset chains, reboot chain (to clean * device units up), device [un]mount chain, module load/unload chain, - * low memory chain, screenblank chain (for plug in modular screenblankers) + * low memory chain, screenblank chain (for plug in modular screenblankers) * VC switch chains (for loadable kernel svgalib VC switch helpers) etc... */ - + /* CPU notfiers are defined in include/linux/cpu.h. */ /* netdevice notifiers are defined in include/linux/netdevice.h */ @ include/linux/percpu-rwsem.h:32 @ static struct percpu_rw_semaphore name = { \ extern int __percpu_down_read(struct percpu_rw_semaphore *, int); extern void __percpu_up_read(struct percpu_rw_semaphore *); -static inline void percpu_down_read_preempt_disable(struct percpu_rw_semaphore *sem) +static inline void percpu_down_read(struct percpu_rw_semaphore *sem) { might_sleep(); @ include/linux/percpu-rwsem.h:50 @ static inline void percpu_down_read_preempt_disable(struct percpu_rw_semaphore * __this_cpu_inc(*sem->read_count); if (unlikely(!rcu_sync_is_idle(&sem->rss))) __percpu_down_read(sem, false); /* Unconditional memory barrier */ - barrier(); /* - * The barrier() prevents the compiler from + * The preempt_enable() prevents the compiler from * bleeding the critical section out. */ -} - -static inline void percpu_down_read(struct percpu_rw_semaphore *sem) -{ - percpu_down_read_preempt_disable(sem); preempt_enable(); } @ include/linux/percpu-rwsem.h:80 @ static inline int percpu_down_read_trylock(struct percpu_rw_semaphore *sem) return ret; } -static inline void percpu_up_read_preempt_enable(struct percpu_rw_semaphore *sem) +static inline void percpu_up_read(struct percpu_rw_semaphore *sem) { - /* - * The barrier() prevents the compiler from - * bleeding the critical section out. - */ - barrier(); + preempt_disable(); /* * Same as in percpu_down_read(). */ @ include/linux/percpu-rwsem.h:95 @ static inline void percpu_up_read_preempt_enable(struct percpu_rw_semaphore *sem rwsem_release(&sem->rw_sem.dep_map, 1, _RET_IP_); } -static inline void percpu_up_read(struct percpu_rw_semaphore *sem) -{ - preempt_disable(); - percpu_up_read_preempt_enable(sem); -} - extern void percpu_down_write(struct percpu_rw_semaphore *); extern void percpu_up_write(struct percpu_rw_semaphore *); @ include/linux/percpu.h:22 @ #define PERCPU_MODULE_RESERVE 0 #endif +#ifdef CONFIG_PREEMPT_RT_FULL + +#define get_local_var(var) (*({ \ + migrate_disable(); \ + this_cpu_ptr(&var); })) + +#define put_local_var(var) do { \ + (void)&(var); \ + migrate_enable(); \ +} while (0) + +# define get_local_ptr(var) ({ \ + migrate_disable(); \ + this_cpu_ptr(var); }) + +# define put_local_ptr(var) do { \ + (void)(var); \ + migrate_enable(); \ +} while (0) + +#else + +#define get_local_var(var) get_cpu_var(var) +#define put_local_var(var) put_cpu_var(var) +#define get_local_ptr(var) get_cpu_ptr(var) +#define put_local_ptr(var) put_cpu_ptr(var) + +#endif + /* minimum unit size, also is the maximum supported allocation size */ #define PCPU_MIN_UNIT_SIZE PFN_ALIGN(32 << 10) @ include/linux/pid.h:6 @ #define _LINUX_PID_H #include <linux/rculist.h> +#include <linux/atomic.h> enum pid_type { @ include/linux/posix-timers.h:117 @ struct k_itimer { struct { struct alarm alarmtimer; } alarm; - struct rcu_head rcu; } it; + struct rcu_head rcu; }; void run_posix_cpu_timers(struct task_struct *task); @ include/linux/preempt.h:54 @ #define HARDIRQ_OFFSET (1UL << HARDIRQ_SHIFT) #define NMI_OFFSET (1UL << NMI_SHIFT) -#define SOFTIRQ_DISABLE_OFFSET (2 * SOFTIRQ_OFFSET) +#ifndef CONFIG_PREEMPT_RT_FULL +# define SOFTIRQ_DISABLE_OFFSET (2 * SOFTIRQ_OFFSET) +#else +# define SOFTIRQ_DISABLE_OFFSET (0) +#endif /* We use the MSB mostly because its available */ #define PREEMPT_NEED_RESCHED 0x80000000 @ include/linux/preempt.h:88 @ #include <asm/preempt.h> #define hardirq_count() (preempt_count() & HARDIRQ_MASK) -#define softirq_count() (preempt_count() & SOFTIRQ_MASK) #define irq_count() (preempt_count() & (HARDIRQ_MASK | SOFTIRQ_MASK \ | NMI_MASK)) +#ifndef CONFIG_PREEMPT_RT_FULL +# define softirq_count() (preempt_count() & SOFTIRQ_MASK) +# define in_serving_softirq() (softirq_count() & SOFTIRQ_OFFSET) +#else +# define softirq_count() ((unsigned long)current->softirq_nestcnt) +extern int in_serving_softirq(void); +#endif /* * Are we doing bottom half or hardware interrupt processing? @ include/linux/preempt.h:114 @ #define in_irq() (hardirq_count()) #define in_softirq() (softirq_count()) #define in_interrupt() (irq_count()) -#define in_serving_softirq() (softirq_count() & SOFTIRQ_OFFSET) #define in_nmi() (preempt_count() & NMI_MASK) #define in_task() (!(preempt_count() & \ (NMI_MASK | HARDIRQ_MASK | SOFTIRQ_OFFSET))) @ include/linux/preempt.h:130 @ /* * The preempt_count offset after spin_lock() */ +#if !defined(CONFIG_PREEMPT_RT_FULL) #define PREEMPT_LOCK_OFFSET PREEMPT_DISABLE_OFFSET +#else +#define PREEMPT_LOCK_OFFSET 0 +#endif /* * The preempt_count offset needed for things like: @ include/linux/preempt.h:183 @ extern void preempt_count_sub(int val); #define preempt_count_inc() preempt_count_add(1) #define preempt_count_dec() preempt_count_sub(1) +#ifdef CONFIG_PREEMPT_LAZY +#define add_preempt_lazy_count(val) do { preempt_lazy_count() += (val); } while (0) +#define sub_preempt_lazy_count(val) do { preempt_lazy_count() -= (val); } while (0) +#define inc_preempt_lazy_count() add_preempt_lazy_count(1) +#define dec_preempt_lazy_count() sub_preempt_lazy_count(1) +#define preempt_lazy_count() (current_thread_info()->preempt_lazy_count) +#else +#define add_preempt_lazy_count(val) do { } while (0) +#define sub_preempt_lazy_count(val) do { } while (0) +#define inc_preempt_lazy_count() do { } while (0) +#define dec_preempt_lazy_count() do { } while (0) +#define preempt_lazy_count() (0) +#endif + #ifdef CONFIG_PREEMPT_COUNT #define preempt_disable() \ @ include/linux/preempt.h:205 @ do { \ barrier(); \ } while (0) +#define preempt_lazy_disable() \ +do { \ + inc_preempt_lazy_count(); \ + barrier(); \ +} while (0) + #define sched_preempt_enable_no_resched() \ do { \ barrier(); \ preempt_count_dec(); \ } while (0) -#define preempt_enable_no_resched() sched_preempt_enable_no_resched() +#ifdef CONFIG_PREEMPT_RT_BASE +# define preempt_enable_no_resched() sched_preempt_enable_no_resched() +# define preempt_check_resched_rt() preempt_check_resched() +#else +# define preempt_enable_no_resched() preempt_enable() +# define preempt_check_resched_rt() barrier(); +#endif #define preemptible() (preempt_count() == 0 && !irqs_disabled()) +#ifdef CONFIG_SMP + +extern void migrate_disable(void); +extern void migrate_enable(void); + +int __migrate_disabled(struct task_struct *p); + +#elif !defined(CONFIG_SMP) && defined(CONFIG_PREEMPT_RT_BASE) + +extern void migrate_disable(void); +extern void migrate_enable(void); +static inline int __migrate_disabled(struct task_struct *p) +{ + return 0; +} + +#else +#define migrate_disable() barrier() +#define migrate_enable() barrier() +static inline int __migrate_disabled(struct task_struct *p) +{ + return 0; +} +#endif + #ifdef CONFIG_PREEMPT #define preempt_enable() \ do { \ @ include/linux/preempt.h:273 @ do { \ __preempt_schedule(); \ } while (0) +#define preempt_lazy_enable() \ +do { \ + dec_preempt_lazy_count(); \ + barrier(); \ + preempt_check_resched(); \ +} while (0) + #else /* !CONFIG_PREEMPT */ #define preempt_enable() \ do { \ @ include/linux/preempt.h:287 @ do { \ preempt_count_dec(); \ } while (0) +#define preempt_lazy_enable() \ +do { \ + dec_preempt_lazy_count(); \ + barrier(); \ +} while (0) + #define preempt_enable_notrace() \ do { \ barrier(); \ @ include/linux/preempt.h:331 @ do { \ #define preempt_disable_notrace() barrier() #define preempt_enable_no_resched_notrace() barrier() #define preempt_enable_notrace() barrier() +#define preempt_check_resched_rt() barrier() #define preemptible() 0 +#define migrate_disable() barrier() +#define migrate_enable() barrier() + +static inline int __migrate_disabled(struct task_struct *p) +{ + return 0; +} #endif /* CONFIG_PREEMPT_COUNT */ #ifdef MODULE @ include/linux/preempt.h:359 @ do { \ } while (0) #define preempt_fold_need_resched() \ do { \ - if (tif_need_resched()) \ + if (tif_need_resched_now()) \ set_preempt_need_resched(); \ } while (0) +#ifdef CONFIG_PREEMPT_RT_FULL +# define preempt_disable_rt() preempt_disable() +# define preempt_enable_rt() preempt_enable() +# define preempt_disable_nort() barrier() +# define preempt_enable_nort() barrier() +#else +# define preempt_disable_rt() barrier() +# define preempt_enable_rt() barrier() +# define preempt_disable_nort() preempt_disable() +# define preempt_enable_nort() preempt_enable() +#endif + #ifdef CONFIG_PREEMPT_NOTIFIERS struct preempt_notifier; @ include/linux/printk.h:143 @ struct va_format { #ifdef CONFIG_EARLY_PRINTK extern asmlinkage __printf(1, 2) void early_printk(const char *fmt, ...); +extern void printk_kill(void); #else static inline __printf(1, 2) __cold void early_printk(const char *s, ...) { } +static inline void printk_kill(void) { } #endif #ifdef CONFIG_PRINTK_NMI @ include/linux/radix-tree.h:329 @ unsigned int radix_tree_gang_lookup_slot(const struct radix_tree_root *, int radix_tree_preload(gfp_t gfp_mask); int radix_tree_maybe_preload(gfp_t gfp_mask); int radix_tree_maybe_preload_order(gfp_t gfp_mask, int order); +void radix_tree_preload_end(void); + void radix_tree_init(void); void *radix_tree_tag_set(struct radix_tree_root *, unsigned long index, unsigned int tag); @ include/linux/radix-tree.h:350 @ unsigned int radix_tree_gang_lookup_tag_slot(const struct radix_tree_root *, unsigned int max_items, unsigned int tag); int radix_tree_tagged(const struct radix_tree_root *, unsigned int tag); -static inline void radix_tree_preload_end(void) -{ - preempt_enable(); -} - int radix_tree_split_preload(unsigned old_order, unsigned new_order, gfp_t); int radix_tree_split(struct radix_tree_root *, unsigned long index, unsigned new_order); @ include/linux/random.h:35 @ static inline void add_latent_entropy(void) {} extern void add_input_randomness(unsigned int type, unsigned int code, unsigned int value) __latent_entropy; -extern void add_interrupt_randomness(int irq, int irq_flags) __latent_entropy; +extern void add_interrupt_randomness(int irq, int irq_flags, __u64 ip) __latent_entropy; extern void get_random_bytes(void *buf, int nbytes); extern int wait_for_random_bytes(void); @ include/linux/rbtree.h:34 @ #include <linux/kernel.h> #include <linux/stddef.h> -#include <linux/rcupdate.h> +#include <linux/rcu_assign_pointer.h> struct rb_node { unsigned long __rb_parent_color; @ include/linux/rbtree_augmented.h:29 @ #include <linux/compiler.h> #include <linux/rbtree.h> +#include <linux/rcupdate.h> /* * Please note - only struct rb_augment_callbacks and the prototypes for @ include/linux/rbtree_latch.h:38 @ #include <linux/rbtree.h> #include <linux/seqlock.h> +#include <linux/rcupdate.h> struct latch_tree_node { struct rb_node node[2]; @ include/linux/rcu_assign_pointer.h:4 @ +#ifndef __LINUX_RCU_ASSIGN_POINTER_H__ +#define __LINUX_RCU_ASSIGN_POINTER_H__ +#include <linux/compiler.h> +#include <asm/barrier.h> + +/** + * RCU_INITIALIZER() - statically initialize an RCU-protected global variable + * @v: The value to statically initialize with. + */ +#define RCU_INITIALIZER(v) (typeof(*(v)) __force __rcu *)(v) + +/** + * rcu_assign_pointer() - assign to RCU-protected pointer + * @p: pointer to assign to + * @v: value to assign (publish) + * + * Assigns the specified value to the specified RCU-protected + * pointer, ensuring that any concurrent RCU readers will see + * any prior initialization. + * + * Inserts memory barriers on architectures that require them + * (which is most of them), and also prevents the compiler from + * reordering the code that initializes the structure after the pointer + * assignment. More importantly, this call documents which pointers + * will be dereferenced by RCU read-side code. + * + * In some special cases, you may use RCU_INIT_POINTER() instead + * of rcu_assign_pointer(). RCU_INIT_POINTER() is a bit faster due + * to the fact that it does not constrain either the CPU or the compiler. + * That said, using RCU_INIT_POINTER() when you should have used + * rcu_assign_pointer() is a very bad thing that results in + * impossible-to-diagnose memory corruption. So please be careful. + * See the RCU_INIT_POINTER() comment header for details. + * + * Note that rcu_assign_pointer() evaluates each of its arguments only + * once, appearances notwithstanding. One of the "extra" evaluations + * is in typeof() and the other visible only to sparse (__CHECKER__), + * neither of which actually execute the argument. As with most cpp + * macros, this execute-arguments-only-once property is important, so + * please be careful when making changes to rcu_assign_pointer() and the + * other macros that it invokes. + */ +#define rcu_assign_pointer(p, v) \ +({ \ + uintptr_t _r_a_p__v = (uintptr_t)(v); \ + \ + if (__builtin_constant_p(v) && (_r_a_p__v) == (uintptr_t)NULL) \ + WRITE_ONCE((p), (typeof(p))(_r_a_p__v)); \ + else \ + smp_store_release(&p, RCU_INITIALIZER((typeof(p))_r_a_p__v)); \ + _r_a_p__v; \ +}) + +#endif @ include/linux/rcupdate.h:45 @ #include <linux/lockdep.h> #include <asm/processor.h> #include <linux/cpumask.h> +#include <linux/rcu_assign_pointer.h> #define ULONG_CMP_GE(a, b) (ULONG_MAX / 2 >= (a) - (b)) #define ULONG_CMP_LT(a, b) (ULONG_MAX / 2 < (a) - (b)) @ include/linux/rcupdate.h:59 @ void call_rcu(struct rcu_head *head, rcu_callback_t func); #define call_rcu call_rcu_sched #endif /* #else #ifdef CONFIG_PREEMPT_RCU */ +#ifdef CONFIG_PREEMPT_RT_FULL +#define call_rcu_bh call_rcu +#else void call_rcu_bh(struct rcu_head *head, rcu_callback_t func); +#endif void call_rcu_sched(struct rcu_head *head, rcu_callback_t func); void synchronize_sched(void); void rcu_barrier_tasks(void); @ include/linux/rcupdate.h:82 @ void synchronize_rcu(void); * types of kernel builds, the rcu_read_lock() nesting depth is unknowable. */ #define rcu_preempt_depth() (current->rcu_read_lock_nesting) +#ifndef CONFIG_PREEMPT_RT_FULL +#define sched_rcu_preempt_depth() rcu_preempt_depth() +#else +static inline int sched_rcu_preempt_depth(void) { return 0; } +#endif #else /* #ifdef CONFIG_PREEMPT_RCU */ @ include/linux/rcupdate.h:112 @ static inline int rcu_preempt_depth(void) return 0; } +#define sched_rcu_preempt_depth() rcu_preempt_depth() + #endif /* #else #ifdef CONFIG_PREEMPT_RCU */ /* Internal to kernel */ @ include/linux/rcupdate.h:270 @ extern struct lockdep_map rcu_sched_lock_map; extern struct lockdep_map rcu_callback_map; int debug_lockdep_rcu_enabled(void); int rcu_read_lock_held(void); +#ifdef CONFIG_PREEMPT_RT_FULL +static inline int rcu_read_lock_bh_held(void) +{ + return rcu_read_lock_held(); +} +#else int rcu_read_lock_bh_held(void); +#endif int rcu_read_lock_sched_held(void); #else /* #ifdef CONFIG_DEBUG_LOCK_ALLOC */ @ include/linux/rcupdate.h:386 @ static inline void rcu_preempt_sleep_check(void) { } ((typeof(*p) __force __kernel *)(________p1)); \ }) -/** - * RCU_INITIALIZER() - statically initialize an RCU-protected global variable - * @v: The value to statically initialize with. - */ -#define RCU_INITIALIZER(v) (typeof(*(v)) __force __rcu *)(v) - -/** - * rcu_assign_pointer() - assign to RCU-protected pointer - * @p: pointer to assign to - * @v: value to assign (publish) - * - * Assigns the specified value to the specified RCU-protected - * pointer, ensuring that any concurrent RCU readers will see - * any prior initialization. - * - * Inserts memory barriers on architectures that require them - * (which is most of them), and also prevents the compiler from - * reordering the code that initializes the structure after the pointer - * assignment. More importantly, this call documents which pointers - * will be dereferenced by RCU read-side code. - * - * In some special cases, you may use RCU_INIT_POINTER() instead - * of rcu_assign_pointer(). RCU_INIT_POINTER() is a bit faster due - * to the fact that it does not constrain either the CPU or the compiler. - * That said, using RCU_INIT_POINTER() when you should have used - * rcu_assign_pointer() is a very bad thing that results in - * impossible-to-diagnose memory corruption. So please be careful. - * See the RCU_INIT_POINTER() comment header for details. - * - * Note that rcu_assign_pointer() evaluates each of its arguments only - * once, appearances notwithstanding. One of the "extra" evaluations - * is in typeof() and the other visible only to sparse (__CHECKER__), - * neither of which actually execute the argument. As with most cpp - * macros, this execute-arguments-only-once property is important, so - * please be careful when making changes to rcu_assign_pointer() and the - * other macros that it invokes. - */ -#define rcu_assign_pointer(p, v) \ -({ \ - uintptr_t _r_a_p__v = (uintptr_t)(v); \ - \ - if (__builtin_constant_p(v) && (_r_a_p__v) == (uintptr_t)NULL) \ - WRITE_ONCE((p), (typeof(p))(_r_a_p__v)); \ - else \ - smp_store_release(&p, RCU_INITIALIZER((typeof(p))_r_a_p__v)); \ - _r_a_p__v; \ -}) - /** * rcu_swap_protected() - swap an RCU and a regular pointer * @rcu_ptr: RCU pointer @ include/linux/rcupdate.h:680 @ static inline void rcu_read_unlock(void) static inline void rcu_read_lock_bh(void) { local_bh_disable(); +#ifdef CONFIG_PREEMPT_RT_FULL + rcu_read_lock(); +#else __acquire(RCU_BH); rcu_lock_acquire(&rcu_bh_lock_map); RCU_LOCKDEP_WARN(!rcu_is_watching(), "rcu_read_lock_bh() used illegally while idle"); +#endif } /* @ include/linux/rcupdate.h:697 @ static inline void rcu_read_lock_bh(void) */ static inline void rcu_read_unlock_bh(void) { +#ifdef CONFIG_PREEMPT_RT_FULL + rcu_read_unlock(); +#else RCU_LOCKDEP_WARN(!rcu_is_watching(), "rcu_read_unlock_bh() used illegally while idle"); rcu_lock_release(&rcu_bh_lock_map); __release(RCU_BH); +#endif local_bh_enable(); } @ include/linux/rcutree.h:47 @ static inline void rcu_virt_note_context_switch(int cpu) rcu_note_context_switch(false); } +#ifdef CONFIG_PREEMPT_RT_FULL +# define synchronize_rcu_bh synchronize_rcu +#else void synchronize_rcu_bh(void); +#endif void synchronize_sched_expedited(void); void synchronize_rcu_expedited(void); @ include/linux/rcutree.h:79 @ static inline void synchronize_rcu_bh_expedited(void) } void rcu_barrier(void); +#ifdef CONFIG_PREEMPT_RT_FULL +# define rcu_barrier_bh rcu_barrier +#else void rcu_barrier_bh(void); +#endif void rcu_barrier_sched(void); unsigned long get_state_synchronize_rcu(void); void cond_synchronize_rcu(unsigned long oldstate); @ include/linux/refcount.h:101 @ extern __must_check bool refcount_dec_if_one(refcount_t *r); extern __must_check bool refcount_dec_not_one(refcount_t *r); extern __must_check bool refcount_dec_and_mutex_lock(refcount_t *r, struct mutex *lock); extern __must_check bool refcount_dec_and_lock(refcount_t *r, spinlock_t *lock); - +extern __must_check bool refcount_dec_and_lock_irqsave(refcount_t *r, + spinlock_t *lock, + unsigned long *flags); #endif /* _LINUX_REFCOUNT_H */ @ include/linux/ring_buffer.h:37 @ struct ring_buffer_event { * array[0] = time delta (28 .. 59) * size = 8 bytes * - * @RINGBUF_TYPE_TIME_STAMP: Sync time stamp with external clock - * array[0] = tv_nsec - * array[1..2] = tv_sec - * size = 16 bytes + * @RINGBUF_TYPE_TIME_STAMP: Absolute timestamp + * Same format as TIME_EXTEND except that the + * value is an absolute timestamp, not a delta + * event.time_delta contains bottom 27 bits + * array[0] = top (28 .. 59) bits + * size = 8 bytes * * <= @RINGBUF_TYPE_DATA_TYPE_LEN_MAX: * Data record @ include/linux/ring_buffer.h:59 @ enum ring_buffer_type { RINGBUF_TYPE_DATA_TYPE_LEN_MAX = 28, RINGBUF_TYPE_PADDING, RINGBUF_TYPE_TIME_EXTEND, - /* FIXME: RINGBUF_TYPE_TIME_STAMP not implemented */ RINGBUF_TYPE_TIME_STAMP, }; unsigned ring_buffer_event_length(struct ring_buffer_event *event); void *ring_buffer_event_data(struct ring_buffer_event *event); +u64 ring_buffer_event_time_stamp(struct ring_buffer_event *event); /* * ring_buffer_discard_commit will remove an event that has not @ include/linux/ring_buffer.h:120 @ int ring_buffer_unlock_commit(struct ring_buffer *buffer, int ring_buffer_write(struct ring_buffer *buffer, unsigned long length, void *data); +void ring_buffer_nest_start(struct ring_buffer *buffer); +void ring_buffer_nest_end(struct ring_buffer *buffer); + struct ring_buffer_event * ring_buffer_peek(struct ring_buffer *buffer, int cpu, u64 *ts, unsigned long *lost_events); @ include/linux/ring_buffer.h:186 @ void ring_buffer_normalize_time_stamp(struct ring_buffer *buffer, int cpu, u64 *ts); void ring_buffer_set_clock(struct ring_buffer *buffer, u64 (*clock)(void)); +void ring_buffer_set_time_stamp_abs(struct ring_buffer *buffer, bool abs); +bool ring_buffer_time_stamp_abs(struct ring_buffer *buffer); size_t ring_buffer_page_len(void *page); @ include/linux/rtmutex.h:17 @ #define __LINUX_RT_MUTEX_H #include <linux/linkage.h> +#include <linux/spinlock_types_raw.h> #include <linux/rbtree.h> -#include <linux/spinlock_types.h> extern int max_lock_depth; /* for sysctl */ +#ifdef CONFIG_DEBUG_MUTEXES +#include <linux/debug_locks.h> +#endif + /** * The rt_mutex structure * @ include/linux/rtmutex.h:38 @ struct rt_mutex { raw_spinlock_t wait_lock; struct rb_root_cached waiters; struct task_struct *owner; -#ifdef CONFIG_DEBUG_RT_MUTEXES int save_state; +#ifdef CONFIG_DEBUG_RT_MUTEXES const char *name, *file; int line; void *magic; @ include/linux/rtmutex.h:89 @ do { \ #define __DEP_MAP_RT_MUTEX_INITIALIZER(mutexname) #endif -#define __RT_MUTEX_INITIALIZER(mutexname) \ - { .wait_lock = __RAW_SPIN_LOCK_UNLOCKED(mutexname.wait_lock) \ +#define __RT_MUTEX_INITIALIZER_PLAIN(mutexname) \ + .wait_lock = __RAW_SPIN_LOCK_UNLOCKED(mutexname.wait_lock) \ , .waiters = RB_ROOT_CACHED \ , .owner = NULL \ __DEBUG_RT_MUTEX_INITIALIZER(mutexname) \ - __DEP_MAP_RT_MUTEX_INITIALIZER(mutexname)} + __DEP_MAP_RT_MUTEX_INITIALIZER(mutexname) + +#define __RT_MUTEX_INITIALIZER(mutexname) \ + { __RT_MUTEX_INITIALIZER_PLAIN(mutexname) } #define DEFINE_RT_MUTEX(mutexname) \ struct rt_mutex mutexname = __RT_MUTEX_INITIALIZER(mutexname) +#define __RT_MUTEX_INITIALIZER_SAVE_STATE(mutexname) \ + { __RT_MUTEX_INITIALIZER_PLAIN(mutexname) \ + , .save_state = 1 } + /** * rt_mutex_is_locked - is the mutex locked * @lock: the mutex to be queried @ include/linux/rtmutex.h:122 @ extern void rt_mutex_destroy(struct rt_mutex *lock); extern void rt_mutex_lock(struct rt_mutex *lock); extern int rt_mutex_lock_interruptible(struct rt_mutex *lock); +extern int rt_mutex_lock_killable(struct rt_mutex *lock); extern int rt_mutex_timed_lock(struct rt_mutex *lock, struct hrtimer_sleeper *timeout); @ include/linux/rwlock_rt.h:4 @ +#ifndef __LINUX_RWLOCK_RT_H +#define __LINUX_RWLOCK_RT_H + +#ifndef __LINUX_SPINLOCK_H +#error Do not include directly. Use spinlock.h +#endif + +extern void __lockfunc rt_write_lock(rwlock_t *rwlock); +extern void __lockfunc rt_read_lock(rwlock_t *rwlock); +extern int __lockfunc rt_write_trylock(rwlock_t *rwlock); +extern int __lockfunc rt_read_trylock(rwlock_t *rwlock); +extern void __lockfunc rt_write_unlock(rwlock_t *rwlock); +extern void __lockfunc rt_read_unlock(rwlock_t *rwlock); +extern int __lockfunc rt_read_can_lock(rwlock_t *rwlock); +extern int __lockfunc rt_write_can_lock(rwlock_t *rwlock); +extern void __rt_rwlock_init(rwlock_t *rwlock, char *name, struct lock_class_key *key); + +#define read_can_lock(rwlock) rt_read_can_lock(rwlock) +#define write_can_lock(rwlock) rt_write_can_lock(rwlock) + +#define read_trylock(lock) __cond_lock(lock, rt_read_trylock(lock)) +#define write_trylock(lock) __cond_lock(lock, rt_write_trylock(lock)) + +static inline int __write_trylock_rt_irqsave(rwlock_t *lock, unsigned long *flags) +{ + /* XXX ARCH_IRQ_ENABLED */ + *flags = 0; + return rt_write_trylock(lock); +} + +#define write_trylock_irqsave(lock, flags) \ + __cond_lock(lock, __write_trylock_rt_irqsave(lock, &(flags))) + +#define read_lock_irqsave(lock, flags) \ + do { \ + typecheck(unsigned long, flags); \ + rt_read_lock(lock); \ + flags = 0; \ + } while (0) + +#define write_lock_irqsave(lock, flags) \ + do { \ + typecheck(unsigned long, flags); \ + rt_write_lock(lock); \ + flags = 0; \ + } while (0) + +#define read_lock(lock) rt_read_lock(lock) + +#define read_lock_bh(lock) \ + do { \ + local_bh_disable(); \ + rt_read_lock(lock); \ + } while (0) + +#define read_lock_irq(lock) read_lock(lock) + +#define write_lock(lock) rt_write_lock(lock) + +#define write_lock_bh(lock) \ + do { \ + local_bh_disable(); \ + rt_write_lock(lock); \ + } while (0) + +#define write_lock_irq(lock) write_lock(lock) + +#define read_unlock(lock) rt_read_unlock(lock) + +#define read_unlock_bh(lock) \ + do { \ + rt_read_unlock(lock); \ + local_bh_enable(); \ + } while (0) + +#define read_unlock_irq(lock) read_unlock(lock) + +#define write_unlock(lock) rt_write_unlock(lock) + +#define write_unlock_bh(lock) \ + do { \ + rt_write_unlock(lock); \ + local_bh_enable(); \ + } while (0) + +#define write_unlock_irq(lock) write_unlock(lock) + +#define read_unlock_irqrestore(lock, flags) \ + do { \ + typecheck(unsigned long, flags); \ + (void) flags; \ + rt_read_unlock(lock); \ + } while (0) + +#define write_unlock_irqrestore(lock, flags) \ + do { \ + typecheck(unsigned long, flags); \ + (void) flags; \ + rt_write_unlock(lock); \ + } while (0) + +#define rwlock_init(rwl) \ +do { \ + static struct lock_class_key __key; \ + \ + __rt_rwlock_init(rwl, #rwl, &__key); \ +} while (0) + +/* + * Internal functions made global for CPU pinning + */ +void __read_rt_lock(struct rt_rw_lock *lock); +int __read_rt_trylock(struct rt_rw_lock *lock); +void __write_rt_lock(struct rt_rw_lock *lock); +int __write_rt_trylock(struct rt_rw_lock *lock); +void __read_rt_unlock(struct rt_rw_lock *lock); +void __write_rt_unlock(struct rt_rw_lock *lock); + +#endif @ include/linux/rwlock_types.h:4 @ #ifndef __LINUX_RWLOCK_TYPES_H #define __LINUX_RWLOCK_TYPES_H +#if !defined(__LINUX_SPINLOCK_TYPES_H) +# error "Do not include directly, include spinlock_types.h" +#endif + /* * include/linux/rwlock_types.h - generic rwlock type definitions * and initializers @ include/linux/rwlock_types_rt.h:4 @ +#ifndef __LINUX_RWLOCK_TYPES_RT_H +#define __LINUX_RWLOCK_TYPES_RT_H + +#ifndef __LINUX_SPINLOCK_TYPES_H +#error "Do not include directly. Include spinlock_types.h instead" +#endif + +#ifdef CONFIG_DEBUG_LOCK_ALLOC +# define RW_DEP_MAP_INIT(lockname) .dep_map = { .name = #lockname } +#else +# define RW_DEP_MAP_INIT(lockname) +#endif + +typedef struct rt_rw_lock rwlock_t; + +#define __RW_LOCK_UNLOCKED(name) __RWLOCK_RT_INITIALIZER(name) + +#define DEFINE_RWLOCK(name) \ + rwlock_t name = __RW_LOCK_UNLOCKED(name) + +/* + * A reader biased implementation primarily for CPU pinning. + * + * Can be selected as general replacement for the single reader RT rwlock + * variant + */ +struct rt_rw_lock { + struct rt_mutex rtmutex; + atomic_t readers; +#ifdef CONFIG_DEBUG_LOCK_ALLOC + struct lockdep_map dep_map; +#endif +}; + +#define READER_BIAS (1U << 31) +#define WRITER_BIAS (1U << 30) + +#define __RWLOCK_RT_INITIALIZER(name) \ +{ \ + .readers = ATOMIC_INIT(READER_BIAS), \ + .rtmutex = __RT_MUTEX_INITIALIZER_SAVE_STATE(name.rtmutex), \ + RW_DEP_MAP_INIT(name) \ +} + +void __rwlock_biased_rt_init(struct rt_rw_lock *lock, const char *name, + struct lock_class_key *key); + +#define rwlock_biased_rt_init(rwlock) \ + do { \ + static struct lock_class_key __key; \ + \ + __rwlock_biased_rt_init((rwlock), #rwlock, &__key); \ + } while (0) + +#endif @ include/linux/rwsem.h:23 @ #include <linux/osq_lock.h> #endif +#ifdef CONFIG_PREEMPT_RT_FULL +#include <linux/rwsem_rt.h> +#else /* PREEMPT_RT_FULL */ + struct rw_semaphore; #ifdef CONFIG_RWSEM_GENERIC_SPINLOCK @ include/linux/rwsem.h:115 @ static inline int rwsem_is_contended(struct rw_semaphore *sem) return !list_empty(&sem->wait_list); } +#endif /* !PREEMPT_RT_FULL */ + +/* + * The functions below are the same for all rwsem implementations including + * the RT specific variant. + */ + /* * lock for reading */ @ include/linux/rwsem_rt.h:4 @ +#ifndef _LINUX_RWSEM_RT_H +#define _LINUX_RWSEM_RT_H + +#ifndef _LINUX_RWSEM_H +#error "Include rwsem.h" +#endif + +#include <linux/rtmutex.h> +#include <linux/swait.h> + +#define READER_BIAS (1U << 31) +#define WRITER_BIAS (1U << 30) + +struct rw_semaphore { + atomic_t readers; + struct rt_mutex rtmutex; +#ifdef CONFIG_DEBUG_LOCK_ALLOC + struct lockdep_map dep_map; +#endif +}; + +#define __RWSEM_INITIALIZER(name) \ +{ \ + .readers = ATOMIC_INIT(READER_BIAS), \ + .rtmutex = __RT_MUTEX_INITIALIZER(name.rtmutex), \ + RW_DEP_MAP_INIT(name) \ +} + +#define DECLARE_RWSEM(lockname) \ + struct rw_semaphore lockname = __RWSEM_INITIALIZER(lockname) + +extern void __rwsem_init(struct rw_semaphore *rwsem, const char *name, + struct lock_class_key *key); + +#define __init_rwsem(sem, name, key) \ +do { \ + rt_mutex_init(&(sem)->rtmutex); \ + __rwsem_init((sem), (name), (key)); \ +} while (0) + +#define init_rwsem(sem) \ +do { \ + static struct lock_class_key __key; \ + \ + __init_rwsem((sem), #sem, &__key); \ +} while (0) + +static inline int rwsem_is_locked(struct rw_semaphore *sem) +{ + return atomic_read(&sem->readers) != READER_BIAS; +} + +static inline int rwsem_is_contended(struct rw_semaphore *sem) +{ + return atomic_read(&sem->readers) > 0; +} + +extern void __down_read(struct rw_semaphore *sem); +extern int __down_read_killable(struct rw_semaphore *sem); +extern int __down_read_trylock(struct rw_semaphore *sem); +extern void __down_write(struct rw_semaphore *sem); +extern int __must_check __down_write_killable(struct rw_semaphore *sem); +extern int __down_write_trylock(struct rw_semaphore *sem); +extern void __up_read(struct rw_semaphore *sem); +extern void __up_write(struct rw_semaphore *sem); +extern void __downgrade_write(struct rw_semaphore *sem); + +#endif @ include/linux/sched.h:30 @ #include <linux/signal_types.h> #include <linux/mm_types_task.h> #include <linux/task_io_accounting.h> +#include <asm/kmap_types.h> /* task_struct member predeclarations (sorted alphabetically): */ struct audit_context; @ include/linux/sched.h:97 @ struct task_group; /* Convenience macros for the sake of wake_up(): */ #define TASK_NORMAL (TASK_INTERRUPTIBLE | TASK_UNINTERRUPTIBLE) -#define TASK_ALL (TASK_NORMAL | __TASK_STOPPED | __TASK_TRACED) /* get_task_state(): */ #define TASK_REPORT (TASK_RUNNING | TASK_INTERRUPTIBLE | \ @ include/linux/sched.h:104 @ struct task_group; __TASK_TRACED | EXIT_DEAD | EXIT_ZOMBIE | \ TASK_PARKED) -#define task_is_traced(task) ((task->state & __TASK_TRACED) != 0) - #define task_is_stopped(task) ((task->state & __TASK_STOPPED) != 0) -#define task_is_stopped_or_traced(task) ((task->state & (__TASK_STOPPED | __TASK_TRACED)) != 0) - #define task_contributes_to_load(task) ((task->state & TASK_UNINTERRUPTIBLE) != 0 && \ (task->flags & PF_FROZEN) == 0 && \ (task->state & TASK_NOLOAD) == 0) @ include/linux/sched.h:123 @ struct task_group; smp_store_mb(current->state, (state_value)); \ } while (0) +#define __set_current_state_no_track(state_value) \ + current->state = (state_value); +#define set_current_state_no_track(state_value) \ + smp_store_mb(current->state, (state_value)); + #else /* * set_current_state() includes a barrier so that the write of current->state @ include/linux/sched.h:165 @ struct task_group; */ #define __set_current_state(state_value) do { current->state = (state_value); } while (0) #define set_current_state(state_value) smp_store_mb(current->state, (state_value)) + +#define __set_current_state_no_track(state_value) __set_current_state(state_value) +#define set_current_state_no_track(state_value) set_current_state(state_value) #endif /* Task command name length: */ @ include/linux/sched.h:538 @ struct task_struct { #endif /* -1 unrunnable, 0 runnable, >0 stopped: */ volatile long state; + /* saved state for "spinlock sleepers" */ + volatile long saved_state; /* * This begins the randomizable portion of task_struct. Only @ include/linux/sched.h:600 @ struct task_struct { unsigned int policy; int nr_cpus_allowed; - cpumask_t cpus_allowed; + const cpumask_t *cpus_ptr; + cpumask_t cpus_mask; +#if defined(CONFIG_PREEMPT_COUNT) && defined(CONFIG_SMP) + int migrate_disable; + int migrate_disable_update; + int pinned_on_cpu; +# ifdef CONFIG_SCHED_DEBUG + int migrate_disable_atomic; +# endif + +#elif !defined(CONFIG_SMP) && defined(CONFIG_PREEMPT_RT_BASE) + int migrate_disable; +# ifdef CONFIG_SCHED_DEBUG + int migrate_disable_atomic; +# endif +#endif +#ifdef CONFIG_PREEMPT_RT_FULL + int sleeping_lock; +#endif #ifdef CONFIG_PREEMPT_RCU int rcu_read_lock_nesting; @ include/linux/sched.h:777 @ struct task_struct { #ifdef CONFIG_POSIX_TIMERS struct task_cputime cputime_expires; struct list_head cpu_timers[3]; +#ifdef CONFIG_PREEMPT_RT_BASE + struct task_struct *posix_timer_list; +#endif #endif /* Process credentials: */ @ include/linux/sched.h:823 @ struct task_struct { /* Signal handlers: */ struct signal_struct *signal; struct sighand_struct *sighand; + struct sigqueue *sigqueue_cache; + sigset_t blocked; sigset_t real_blocked; /* Restored if set_restore_sigmask() was used: */ sigset_t saved_sigmask; struct sigpending pending; +#ifdef CONFIG_PREEMPT_RT_FULL + /* TODO: move me into ->restart_block ? */ + struct siginfo forced_info; +#endif unsigned long sas_ss_sp; size_t sas_ss_size; unsigned int sas_ss_flags; @ include/linux/sched.h:858 @ struct task_struct { raw_spinlock_t pi_lock; struct wake_q_node wake_q; + struct wake_q_node wake_q_sleeper; #ifdef CONFIG_RT_MUTEXES /* PI waiters blocked on a rt_mutex held by this task: */ @ include/linux/sched.h:1115 @ struct task_struct { unsigned int sequential_io; unsigned int sequential_io_avg; #endif +#ifdef CONFIG_PREEMPT_RT_BASE + struct rcu_head put_rcu; + int softirq_nestcnt; + unsigned int softirqs_raised; +#endif +#ifdef CONFIG_PREEMPT_RT_FULL +# if defined CONFIG_HIGHMEM || defined CONFIG_X86_32 + int kmap_idx; + pte_t kmap_pte[KM_TYPE_NR]; +# endif +#endif #ifdef CONFIG_DEBUG_ATOMIC_SLEEP unsigned long task_state_change; +#endif +#ifdef CONFIG_PREEMPT_RT_FULL + int xmit_recursion; #endif int pagefault_disabled; #ifdef CONFIG_MMU @ include/linux/sched.h:1345 @ extern struct pid *cad_pid; /* * Per process flags */ +#define PF_IN_SOFTIRQ 0x00000001 /* Task is serving softirq */ #define PF_IDLE 0x00000002 /* I am an IDLE thread */ #define PF_EXITING 0x00000004 /* Getting shut down */ #define PF_EXITPIDONE 0x00000008 /* PI exit done on shut down */ @ include/linux/sched.h:1369 @ extern struct pid *cad_pid; #define PF_KTHREAD 0x00200000 /* I am a kernel thread */ #define PF_RANDOMIZE 0x00400000 /* Randomize virtual address space */ #define PF_SWAPWRITE 0x00800000 /* Allowed to write to swap */ -#define PF_NO_SETAFFINITY 0x04000000 /* Userland is not allowed to meddle with cpus_allowed */ +#define PF_NO_SETAFFINITY 0x04000000 /* Userland is not allowed to meddle with cpus_mask */ #define PF_MCE_EARLY 0x08000000 /* Early kill for mce process policy */ #define PF_MUTEX_TESTER 0x20000000 /* Thread belongs to the rt mutex tester */ #define PF_FREEZER_SKIP 0x40000000 /* Freezer should not count it as freezable */ @ include/linux/sched.h:1564 @ extern struct task_struct *find_get_task_by_vpid(pid_t nr); extern int wake_up_state(struct task_struct *tsk, unsigned int state); extern int wake_up_process(struct task_struct *tsk); +extern int wake_up_lock_sleeper(struct task_struct *tsk); extern void wake_up_new_task(struct task_struct *tsk); #ifdef CONFIG_SMP @ include/linux/sched.h:1641 @ static inline int test_tsk_need_resched(struct task_struct *tsk) return unlikely(test_tsk_thread_flag(tsk,TIF_NEED_RESCHED)); } +#ifdef CONFIG_PREEMPT_LAZY +static inline void set_tsk_need_resched_lazy(struct task_struct *tsk) +{ + set_tsk_thread_flag(tsk,TIF_NEED_RESCHED_LAZY); +} + +static inline void clear_tsk_need_resched_lazy(struct task_struct *tsk) +{ + clear_tsk_thread_flag(tsk,TIF_NEED_RESCHED_LAZY); +} + +static inline int test_tsk_need_resched_lazy(struct task_struct *tsk) +{ + return unlikely(test_tsk_thread_flag(tsk,TIF_NEED_RESCHED_LAZY)); +} + +static inline int need_resched_lazy(void) +{ + return test_thread_flag(TIF_NEED_RESCHED_LAZY); +} + +static inline int need_resched_now(void) +{ + return test_thread_flag(TIF_NEED_RESCHED); +} + +#else +static inline void clear_tsk_need_resched_lazy(struct task_struct *tsk) { } +static inline int need_resched_lazy(void) { return 0; } + +static inline int need_resched_now(void) +{ + return test_thread_flag(TIF_NEED_RESCHED); +} + +#endif + + +static inline bool __task_is_stopped_or_traced(struct task_struct *task) +{ + if (task->state & (__TASK_STOPPED | __TASK_TRACED)) + return true; +#ifdef CONFIG_PREEMPT_RT_FULL + if (task->saved_state & (__TASK_STOPPED | __TASK_TRACED)) + return true; +#endif + return false; +} + +static inline bool task_is_stopped_or_traced(struct task_struct *task) +{ + bool traced_stopped; + +#ifdef CONFIG_PREEMPT_RT_FULL + unsigned long flags; + + raw_spin_lock_irqsave(&task->pi_lock, flags); + traced_stopped = __task_is_stopped_or_traced(task); + raw_spin_unlock_irqrestore(&task->pi_lock, flags); +#else + traced_stopped = __task_is_stopped_or_traced(task); +#endif + return traced_stopped; +} + +static inline bool task_is_traced(struct task_struct *task) +{ + bool traced = false; + + if (task->state & __TASK_TRACED) + return true; +#ifdef CONFIG_PREEMPT_RT_FULL + /* in case the task is sleeping on tasklist_lock */ + raw_spin_lock_irq(&task->pi_lock); + if (task->state & __TASK_TRACED) + traced = true; + else if (task->saved_state & __TASK_TRACED) + traced = true; + raw_spin_unlock_irq(&task->pi_lock); +#endif + return traced; +} + /* * cond_resched() and cond_resched_lock(): latency reduction via * explicit rescheduling in places that are safe. The return @ include/linux/sched.h:1749 @ extern int __cond_resched_lock(spinlock_t *lock); __cond_resched_lock(lock); \ }) +#ifndef CONFIG_PREEMPT_RT_FULL extern int __cond_resched_softirq(void); #define cond_resched_softirq() ({ \ ___might_sleep(__FILE__, __LINE__, SOFTIRQ_DISABLE_OFFSET); \ __cond_resched_softirq(); \ }) +#else +# define cond_resched_softirq() cond_resched() +#endif static inline void cond_resched_rcu(void) { @ include/linux/sched.h:1788 @ static __always_inline bool need_resched(void) return unlikely(tif_need_resched()); } +#ifdef CONFIG_PREEMPT_RT_FULL +static inline void sleeping_lock_inc(void) +{ + current->sleeping_lock++; +} + +static inline void sleeping_lock_dec(void) +{ + current->sleeping_lock--; +} + +#else + +static inline void sleeping_lock_inc(void) { } +static inline void sleeping_lock_dec(void) { } +#endif + /* * Wrappers for p->thread_info->cpu access. No-op on UP. */ @ include/linux/sched/mm.h:52 @ static inline void mmdrop(struct mm_struct *mm) __mmdrop(mm); } +#ifdef CONFIG_PREEMPT_RT_BASE +extern void __mmdrop_delayed(struct rcu_head *rhp); +static inline void mmdrop_delayed(struct mm_struct *mm) +{ + if (atomic_dec_and_test(&mm->mm_count)) + call_rcu(&mm->delayed_drop, __mmdrop_delayed); +} +#else +# define mmdrop_delayed(mm) mmdrop(mm) +#endif + /** * mmget() - Pin the address space associated with a &struct mm_struct. * @mm: The address space to pin. @ include/linux/sched/task.h:91 @ extern void sched_exec(void); #define get_task_struct(tsk) do { atomic_inc(&(tsk)->usage); } while(0) +#ifdef CONFIG_PREEMPT_RT_BASE +extern void __put_task_struct_cb(struct rcu_head *rhp); + +static inline void put_task_struct(struct task_struct *t) +{ + if (atomic_dec_and_test(&t->usage)) + call_rcu(&t->put_rcu, __put_task_struct_cb); +} +#else extern void __put_task_struct(struct task_struct *t); static inline void put_task_struct(struct task_struct *t) @ include/linux/sched/task.h:107 @ static inline void put_task_struct(struct task_struct *t) if (atomic_dec_and_test(&t->usage)) __put_task_struct(t); } - +#endif struct task_struct *task_rcu_dereference(struct task_struct **ptask); #ifdef CONFIG_ARCH_WANTS_DYNAMIC_TASK_STRUCT @ include/linux/sched/user.h:7 @ #include <linux/uidgid.h> #include <linux/atomic.h> +#include <linux/refcount.h> #include <linux/ratelimit.h> struct key; @ include/linux/sched/user.h:16 @ struct key; * Some day this will be a full-fledged user tracking system.. */ struct user_struct { - atomic_t __count; /* reference count */ + refcount_t __count; /* reference count */ atomic_t processes; /* How many processes does this user have? */ atomic_t sigpending; /* How many pending signals does this user have? */ #ifdef CONFIG_FANOTIFY @ include/linux/sched/user.h:63 @ extern struct user_struct root_user; extern struct user_struct * alloc_uid(kuid_t); static inline struct user_struct *get_uid(struct user_struct *u) { - atomic_inc(&u->__count); + refcount_inc(&u->__count); return u; } extern void free_uid(struct user_struct *); @ include/linux/sched/wake_q.h:50 @ static inline void wake_q_init(struct wake_q_head *head) head->lastp = &head->first; } -extern void wake_q_add(struct wake_q_head *head, - struct task_struct *task); -extern void wake_up_q(struct wake_q_head *head); +extern void __wake_q_add(struct wake_q_head *head, + struct task_struct *task, bool sleeper); +static inline void wake_q_add(struct wake_q_head *head, + struct task_struct *task) +{ + __wake_q_add(head, task, false); +} + +static inline void wake_q_add_sleeper(struct wake_q_head *head, + struct task_struct *task) +{ + __wake_q_add(head, task, true); +} + +extern void __wake_up_q(struct wake_q_head *head, bool sleeper); +static inline void wake_up_q(struct wake_q_head *head) +{ + __wake_up_q(head, false); +} + +static inline void wake_up_q_sleeper(struct wake_q_head *head) +{ + __wake_up_q(head, true); +} #endif /* _LINUX_SCHED_WAKE_Q_H */ @ include/linux/seqlock.h:224 @ static inline int read_seqcount_retry(const seqcount_t *s, unsigned start) return __read_seqcount_retry(s, start); } - - -static inline void raw_write_seqcount_begin(seqcount_t *s) +static inline void __raw_write_seqcount_begin(seqcount_t *s) { s->sequence++; smp_wmb(); } -static inline void raw_write_seqcount_end(seqcount_t *s) +static inline void raw_write_seqcount_begin(seqcount_t *s) +{ + preempt_disable_rt(); + __raw_write_seqcount_begin(s); +} + +static inline void __raw_write_seqcount_end(seqcount_t *s) { smp_wmb(); s->sequence++; } +static inline void raw_write_seqcount_end(seqcount_t *s) +{ + __raw_write_seqcount_end(s); + preempt_enable_rt(); +} + /** * raw_write_seqcount_barrier - do a seq write barrier * @s: pointer to seqcount_t @ include/linux/seqlock.h:441 @ typedef struct { /* * Read side functions for starting and finalizing a read side section. */ +#ifndef CONFIG_PREEMPT_RT_FULL static inline unsigned read_seqbegin(const seqlock_t *sl) { return read_seqcount_begin(&sl->seqcount); } +#else +/* + * Starvation safe read side for RT + */ +static inline unsigned read_seqbegin(seqlock_t *sl) +{ + unsigned ret; + +repeat: + ret = READ_ONCE(sl->seqcount.sequence); + if (unlikely(ret & 1)) { + /* + * Take the lock and let the writer proceed (i.e. evtl + * boost it), otherwise we could loop here forever. + */ + spin_unlock_wait(&sl->lock); + goto repeat; + } + smp_rmb(); + return ret; +} +#endif static inline unsigned read_seqretry(const seqlock_t *sl, unsigned start) { @ include/linux/seqlock.h:482 @ static inline unsigned read_seqretry(const