Re: [PATCH 1/2] hrtimer: update '->active_bases' before calling hrtimer_force_reprogram()

From: Viresh Kumar
Date: Thu Apr 02 2015 - 10:24:08 EST

On 2 April 2015 at 19:46, Peter Zijlstra <peterz@xxxxxxxxxxxxx> wrote:
> So then I'm not seeing how its a bug. Sure __hrtimer_get_next_event()
> will iterate all the bases again, and it will not skip the just empty
> one. But I don't see how that is anything but an inefficiency. By virtue
> of the base being empty it cannot find an event there, so its a
> pointless check.
> What am I missing?

Hmm. It was a bug for me because I was doing this unconditionally:
timer = container_of(timerqueue_getnext(&base->active),
+ struct hrtimer, node);

And this will give a container-of over NULL, as timerqueue_getnext() can
return NULL..

And so it will crash in my case.

But I understand your point, its inefficiency only :(
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