Messages in this thread | | | Subject | Re: [PATCH 2/3 v2] futex: avoid double wake up in futex_wake() on -RT | From | Davidlohr Bueso <> | Date | Sun, 12 Apr 2015 20:02:35 -0700 |
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On Fri, 2015-04-10 at 18:11 +0200, Sebastian Andrzej Siewior wrote: > This patch delays the wakeup of the process untill ^^^ until
> the hb->lock is > dropped to avoid boosting + context switch to obtain the lock.
Doing the wakeups while holding the lock is also a general performance issue for futex_wake. The problem being dealing with spurious wakeups (wacky drivers), which makes no difference wrt nr_wake.
Thanks, Davidlohr
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