Subject: Re: utime/stime decreasing on thread exit
From: Peter Zijlstra <peterz@infradead.org>
To: Oleg Nesterov <oleg@redhat.com>
Cc: Hidetoshi Seto <seto.hidetoshi@jp.fujitsu.com>,
       Spencer Candland <spencer@bluehost.com>, linux-kernel@vger.kernel.org,
       Ingo Molnar <mingo@elte.hu>, Stanislaw Gruszka <sgruszka@redhat.com>
In-Reply-To: <20091109192355.GA13724@redhat.com>
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	 <20091109192355.GA13724@redhat.com>
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Date: Mon, 09 Nov 2009 20:32:23 +0100
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On Mon, 2009-11-09 at 20:23 +0100, Oleg Nesterov wrote:
> On 11/09, Peter Zijlstra wrote:
> >
> > On Mon, 2009-11-09 at 18:20 +0100, Oleg Nesterov wrote:
> >
> > > Stanislaw has already sent the patch, but I don't know what happened
> > > with this patch:
> > >
> > > 	[PATCH 1/2] posix-cpu-timers: avoid do_sys_times() races with __exit_signal()
> > > 	http://marc.info/?l=linux-kernel&m=124505545131145
> >
> > That patch has the siglock in the function calling
> > thread_group_cputime(), the 22 code had it near the loop proper, which
> > to me seems a more sensible thing, since there could be more callers,
> > no?
> 
> Well, we can't take ->siglock in thread_group_cputime(), sometimes it
> is called under ->siglock. do_task_stat(), get_cpu_itimer() at least.
> 
> IIRC, Stanislaw verified other callers have no problems with this helper.

Would have made fine changelog material :-)

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