From 2cd4d0ea19713304963dbb2de5073700bfe253f5 Mon Sep 17 00:00:00 2001 From: Ingo Molnar Date: Thu, 26 Jul 2007 13:40:43 +0200 Subject: [PATCH] [PATCH] sched: make cpu_clock() not use the rq clock it is enough to disable interrupts to get the precise rq-clock of the local CPU. this also solves an NMI watchdog regression: the NMI watchdog calls touch_softlockup_watchdog(), which might deadlock on rq->lock if the NMI hits an rq-locked critical section. Signed-off-by: Ingo Molnar --- kernel/sched.c | 7 +++---- 1 file changed, 3 insertions(+), 4 deletions(-) diff --git a/kernel/sched.c b/kernel/sched.c index cc6c1192c4..3eed860cf2 100644 --- a/kernel/sched.c +++ b/kernel/sched.c @@ -383,13 +383,12 @@ static inline unsigned long long rq_clock(struct rq *rq) */ unsigned long long cpu_clock(int cpu) { - struct rq *rq = cpu_rq(cpu); unsigned long long now; unsigned long flags; - spin_lock_irqsave(&rq->lock, flags); - now = rq_clock(rq); - spin_unlock_irqrestore(&rq->lock, flags); + local_irq_save(flags); + now = rq_clock(cpu_rq(cpu)); + local_irq_restore(flags); return now; } -- 2.39.5