From 5bbcfd9000887c0da7d57cc7b3ac869fc0dd5aa9 Mon Sep 17 00:00:00 2001 From: Ingo Molnar Date: Thu, 7 Jul 2005 17:57:04 -0700 Subject: [PATCH] [PATCH] cond_resched(): fix bogus might_sleep() warning The BKS might be reacquired before we have dropped PREEMPT_ACTIVE, which could trigger a second could trigger a second cond_resched() call. Bug found by Hirofumi Ogawa. Signed-off-by: Ingo Molnar Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- kernel/sched.c | 7 +++++++ 1 file changed, 7 insertions(+) diff --git a/kernel/sched.c b/kernel/sched.c index 5f2182d..4107db0 100644 --- a/kernel/sched.c +++ b/kernel/sched.c @@ -3877,6 +3877,13 @@ asmlinkage long sys_sched_yield(void) static inline void __cond_resched(void) { + /* + * The BKS might be reacquired before we have dropped + * PREEMPT_ACTIVE, which could trigger a second + * cond_resched() call. + */ + if (unlikely(preempt_count())) + return; do { add_preempt_count(PREEMPT_ACTIVE); schedule(); -- 2.7.4