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Date: Thu, 3 Dec 2009 11:49:06 +0100
From: Ingo Molnar <mingo@elte.hu>
To: Jan Beulich <JBeulich@novell.com>
Cc: tglx@linutronix.de, hpa@zytor.com, Peter Zijlstra <a.p.zijlstra@chello.nl>,
       Linus Torvalds <torvalds@linux-foundation.org>,
       Nick Piggin <npiggin@suse.de>, linux-kernel@vger.kernel.org
Subject: Re: [PATCH] x86: slightly shorten __ticket_spin_trylock() (v2)
Message-ID: <20091203104906.GC7628@elte.hu>
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* Jan Beulich <JBeulich@novell.com> wrote:

> Since the callers generally expect a boolean value, there's no need to
> zero-extend the outcome of the comparison. It just requires that all
> of x86' trylock implementations have their return type changed
> accordingly.
> 
> Don't use bool for the return type though - this is being frowned on
> and presently doesn't work with the pv-ops patching macros.
> 
> Signed-off-by: Jan Beulich <jbeulich@novell.com>
> Cc: Nick Piggin <npiggin@suse.de>
> Cc: Linus Torvalds <torvalds@linux-foundation.org>
> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
> 
> ---
>  arch/x86/include/asm/paravirt.h       |    4 ++--
>  arch/x86/include/asm/paravirt_types.h |    2 +-
>  arch/x86/include/asm/spinlock.h       |   12 +++++-------
>  arch/x86/xen/spinlock.c               |    2 +-
>  4 files changed, 9 insertions(+), 11 deletions(-)

Looks much cleaner - and should give us pretty much the same savings as 
the previous patch, right? (if not, do you have a size comparison?)

	Ingo