[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 <mingo@elte.hu>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
This commit is contained in:
Ingo Molnar 2005-07-07 17:57:04 -07:00 committed by Linus Torvalds
parent a4014d8f61
commit 5bbcfd9000

View File

@ -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();