Re: 2.6.13-rc6-rt9

From: Ingo Molnar
Date: Mon Aug 22 2005 - 17:31:00 EST



* Steven Rostedt <rostedt@xxxxxxxxxxx> wrote:

> On Fri, 2005-08-19 at 09:00 -0400, Steven Rostedt wrote:
> > On Fri, 2005-08-19 at 02:39 -0400, Steven Rostedt wrote:
>
> > I haven't thought of a good way yet to solve the race condition with
> > dependent sleeper. (Except by turning off CONFIG_WAKEUP_TIMING :-)
> >
>
> OK, I found one simple solution. The problem stems from max_mutex
> being grabbed. Since this uses the RT locks, and since tracing
> shouldn't really care about PI and all that, I switched this to a
> compat_semaphore, but only if CONFIG_WAKEUP_TIMING is set. This seems
> to get rid of this race condition that I have.

ok, i have applied your patch and have done a small tweak: i made it a
compat semaphore unconditionally. There's no point in #ifdefing it on
WAKEUP_TIMING.

> I found more bugs, but for now this message is about this specific
> race.

ok.

Ingo
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