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Merge branch 'timers-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

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Pull timer fixes from Ingo Molnar:
 "Two clocksource driver fixes, and an idle loop RCU warning fix"

* 'timers-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  clocksource/drivers/sun5i: Fix cpufreq interaction with sched_clock()
  clocksource/drivers: Fix various !CONFIG_HAS_IOMEM build errors
  timers/tick/broadcast-hrtimer: Fix suspicious RCU usage in idle loop
This commit is contained in:
Linus Torvalds 2015-03-28 11:21:23 -07:00
commit 4a89452e70
3 changed files with 12 additions and 9 deletions
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11
kernel/time/tick-broadcast-hrtimer.c
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@ -49,6 +49,7 @@ static void bc_set_mode(enum clock_event_mode mode,
*/
static int bc_set_next(ktime_t expires, struct clock_event_device *bc)
{
int bc_moved;
/*
* We try to cancel the timer first. If the callback is on
* flight on some other cpu then we let it handle it. If we
@ -60,9 +61,15 @@ static int bc_set_next(ktime_t expires, struct clock_event_device *bc)
* restart the timer because we are in the callback, but we
* can set the expiry time and let the callback return
* HRTIMER_RESTART.
*
* Since we are in the idle loop at this point and because
* hrtimer_{start/cancel} functions call into tracing,
* calls to these functions must be bound within RCU_NONIDLE.
*/
if (hrtimer_try_to_cancel(&bctimer) >= 0) {
hrtimer_start(&bctimer, expires, HRTIMER_MODE_ABS_PINNED);
RCU_NONIDLE(bc_moved = (hrtimer_try_to_cancel(&bctimer) >= 0) ?
!hrtimer_start(&bctimer, expires, HRTIMER_MODE_ABS_PINNED) :
0);
if (bc_moved) {
/* Bind the "device" to the cpu */
bc->bound_on = smp_processor_id();
} else if (bc->bound_on == smp_processor_id()) {