sched: only update rq->clock while holding rq->lock
authorPeter Zijlstra <peterz@infradead.org>
Wed, 15 Oct 2008 18:37:23 +0000 (20:37 +0200)
committerIngo Molnar <mingo@elte.hu>
Wed, 15 Oct 2008 18:43:27 +0000 (20:43 +0200)
commit8cd162ce230b154e564a1285bb5f89fcf73f0dce
treeaaace0250b44a77d71cd650edaa395d9b3f891e7
parent5b16a2212f1840b63d6cc476b26ff9349dab185e
sched: only update rq->clock while holding rq->lock

Vatsa noticed rq->clock going funny and tracked it down to an update_rq_clock()
outside a rq->lock section.

This is a problem because things like double_rq_lock() update the rq->clock
value for both rqs. Therefore disabling interrupts isn't strong enough.

Reported-by: Srivatsa Vaddagiri <vatsa@linux.vnet.ibm.com>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
kernel/sched.c