From aeb306d28bd3dbbb663ee9d3e5e63ea072cf6e7e Mon Sep 17 00:00:00 2001 From: Sebastian Andrzej Siewior Date: Fri, 16 Jun 2017 19:03:16 +0200 Subject: [PATCH 105/158] net/core: use local_bh_disable() in netif_rx_ni() In 2004 netif_rx_ni() gained a preempt_disable() section around netif_rx() and its do_softirq() + testing for it. The do_softirq() part is required because netif_rx() raises the softirq but does not invoke it. The preempt_disable() is required to remain on the same CPU which added the skb to the per-CPU list. All this can be avoided be putting this into a local_bh_disable()ed section. The local_bh_enable() part will invoke do_softirq() if required. Signed-off-by: Sebastian Andrzej Siewior Signed-off-by: Thomas Gleixner --- net/core/dev.c | 6 ++---- 1 file changed, 2 insertions(+), 4 deletions(-) Index: linux-5.15.19-rt29/net/core/dev.c =================================================================== --- linux-5.15.19-rt29.orig/net/core/dev.c +++ linux-5.15.19-rt29/net/core/dev.c @@ -4955,11 +4955,9 @@ int netif_rx_ni(struct sk_buff *skb) trace_netif_rx_ni_entry(skb); - preempt_disable(); + local_bh_disable(); err = netif_rx_internal(skb); - if (local_softirq_pending()) - do_softirq(); - preempt_enable(); + local_bh_enable(); trace_netif_rx_ni_exit(err); return err;