sched: Cleanup/optimize clock updates

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Now that we no longer depend on the clock being updated prior to enqueueing
on migratory wakeup, we can clean up a bit, placing calls to update_rq_clock()
exactly where they are needed, ie on enqueue, dequeue and schedule events.

In the case of a freshly enqueued task immediately preempting, we can skip the
update during preemption, as the clock was just updated by the enqueue event.
We also save an unneeded call during a migratory wakeup by not updating the
previous runqueue, where update_curr() won't be invoked.

Signed-off-by: Mike Galbraith <efault@gmx.de>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
LKML-Reference: <1268301199.6785.32.camel@marge.simson.net>
Signed-off-by: Ingo Molnar <mingo@elte.hu>

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Mike Galbraith 2010-03-11 17:16:20 +01:00 • committed by Ingo Molnar

parent e12f31d3e5

commit a64692a3af

2 changed files with 16 additions and 18 deletions

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32

kernel/sched.c

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2

kernel/sched_fair.c

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