From f34e62b8d317bfff425ad77c7b27a42eb6c68652 Mon Sep 17 00:00:00 2001 From: Sebastian Andrzej Siewior Date: Thu, 12 Aug 2021 14:40:05 +0200 Subject: [PATCH 079/158] sched: Trigger warning if ->migration_disabled counter underflows. If migrate_enable() is used more often than its counter part then it remains undetected and rq::nr_pinned will underflow, too. Add a warning if migrate_enable() is attempted if without a matching a migrate_disable(). Signed-off-by: Sebastian Andrzej Siewior --- kernel/sched/core.c | 2 ++ 1 file changed, 2 insertions(+) Index: linux-5.15.19-rt29/kernel/sched/core.c =================================================================== --- linux-5.15.19-rt29.orig/kernel/sched/core.c +++ linux-5.15.19-rt29/kernel/sched/core.c @@ -2152,6 +2152,8 @@ void migrate_enable(void) if (p->migration_disabled > 1) { p->migration_disabled--; return; + } else if (WARN_ON_ONCE(p->migration_disabled == 0)) { + return; } /*