Searched hist:"19 d9f4225dd6a47fca430f15eeae345ceb95c301" (Results 1 – 1 of 1) sorted by relevance
| /openbmc/linux/kernel/time/ |
| H A D | hrtimer.c | diff 19d9f4225dd6a47fca430f15eeae345ceb95c301 Tue Apr 14 16:09:25 CDT 2015 Thomas Gleixner <tglx@linutronix.de> hrtimer: Avoid locking in hrtimer_cancel() if timer not active
We can do a lockless check for hrtimer_active before actually taking
the lock in hrtimer[_try_to]_cancel. This is useful for hotpath users
like nanosleep as they avoid the lock dance when the timer has
expired.
This is safe because active is true when the timer is enqueued or the
callback is running. Taking the hrtimer base lock does not protect
against concurrent hrtimer_start calls, the callsite has to do the
proper serialization itself.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Peter Zijlstra <peterz@infradead.org>
Cc: Preeti U Murthy <preeti@linux.vnet.ibm.com>
Cc: Viresh Kumar <viresh.kumar@linaro.org>
Cc: Marcelo Tosatti <mtosatti@redhat.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Link: http://lkml.kernel.org/r/20150414203503.580273114@linutronix.de
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
|