From 97e224dc8fceb3d87ce2ddf6e2a3a96b469dc7a7 Mon Sep 17 00:00:00 2001 From: Sebastian Andrzej Siewior Date: Thu, 12 Aug 2021 14:40:05 +0200 Subject: [PATCH 078/166] 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-5.15.32-rt39/kernel/sched/core.c =================================================================== --- linux-5.15.32-rt39.orig/kernel/sched/core.c +++ linux-5.15.32-rt39/kernel/sched/core.c @@ -2153,6 +2153,8 @@ void migrate_enable(void) if (p->migration_disabled > 1) { p->migration_disabled--; return; + } else if (WARN_ON_ONCE(p->migration_disabled == 0)) { + return; } /*