Date: Mon, 9 Jun 2008 15:20:31 +0200
From: Ingo Molnar <mingo@elte.hu>
To: Matthew Wilcox <matthew@wil.cx>
Cc: Oleg Nesterov <oleg@tv-sign.ru>, Andrew Morton <akpm@linux-foundation.org>,
       Dmitry Adamushko <dmitry.adamushko@gmail.com>,
       Peter Zijlstra <a.p.zijlstra@chello.nl>,
       Roland McGrath <roland@redhat.com>, linux-kernel@vger.kernel.org
Subject: Re: [PATCH 2/2] __down_common: use signal_pending_state()
Message-ID: <20080609132031.GA1737@elte.hu>
References: <20080604170906.GA10276@tv-sign.ru> <20080604173633.GI3549@parisc-linux.org>
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* Matthew Wilcox <matthew@wil.cx> wrote:

> On Wed, Jun 04, 2008 at 09:09:06PM +0400, Oleg Nesterov wrote:
> > Cleanup. __down_common() can use the new signal_pending_state() helper.
> 
> This is a bad optimisation.  __down_common gets inlined and the 
> constant 'state' versions are optimised away for the versions which 
> don't apply.
> 
> NAK this patch.

well but we had a schedule() bug around this whole topic of 
TASK_KILLABLE, so i'd say robustness trumps micro-optimizations. Is this 
really a big issue? The dual-ness of TASK_KILLABLE checks is a bit ugly, 
and it led to a bug as well.

	Ingo
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