From c1e16aa2792a129d8920e22210ef21eb62a0f80a Mon Sep 17 00:00:00 2001 From: Thomas Gleixner Date: Wed, 28 Feb 2007 20:12:19 -0800 Subject: [PATCH] [PATCH] Fix posix-cpu-timer breakage caused by stale p->last_ran value Problem description at: http://bugzilla.kernel.org/show_bug.cgi?id=8048 Commit b18ec80396834497933d77b81ec0918519f4e2a7 [PATCH] sched: improve migration accuracy optimized the scheduler time calculations, but broke posix-cpu-timers. The problem is that the p->last_ran value is not updated after a context switch. So a subsequent call to current_sched_time() calculates with a stale p->last_ran value, i.e. accounts the full time, which the task was scheduled away. Signed-off-by: Thomas Gleixner Acked-by: Ingo Molnar Cc: Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- kernel/sched.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/kernel/sched.c b/kernel/sched.c index 0dc757246d..0c5ebf59b8 100644 --- a/kernel/sched.c +++ b/kernel/sched.c @@ -3566,7 +3566,7 @@ switch_tasks: sched_info_switch(prev, next); if (likely(prev != next)) { - next->timestamp = now; + next->timestamp = next->last_ran = now; rq->nr_switches++; rq->curr = next; ++*switch_count; -- 2.39.5