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Message-ID: <4D0CD3F5.1020401@kernel.org>
Date: Sat, 18 Dec 2010 16:32:05 +0100
From: Tejun Heo <tj@kernel.org>
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To: Christoph Lameter <cl@linux.com>
CC: akpm@linux-foundation.org, Peter Zijlstra <a.p.zijlstra@chello.nl>,
        Pekka Enberg <penberg@cs.helsinki.fi>, linux-kernel@vger.kernel.org,
        Eric Dumazet <eric.dumazet@gmail.com>,
        "H. Peter Anvin" <hpa@zytor.com>,
        Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Subject: Re: [cpuops cmpxchg V2 3/5] irq_work: Use per cpu atomics instead
 of regular atomics
References: <20101214162842.542421046@linux.com> <20101214162854.218751478@linux.com>
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On 12/14/2010 05:28 PM, Christoph Lameter wrote:
> The irq work queue is a per cpu object and it is sufficient for
> synchronization if per cpu atomics are used. Doing so simplifies
> the code and reduces the overhead of the code.
> 
> Before:
> 
> christoph@linux-2.6$ size kernel/irq_work.o
>    text	   data	    bss	    dec	    hex	filename
>     451	      8	      1	    460	    1cc	kernel/irq_work.o
> 
> After:
> 
> christoph@linux-2.6$ size kernel/irq_work.o 
>    text	   data	    bss	    dec	    hex	filename
>     438	      8	      1	    447	    1bf	kernel/irq_work.o
> 
> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
> Signed-off-by: Christoph Lameter <cl@linux.com>

Applied 3 and 4 to percpu#for-2.6.38.

Thank you.

-- 
tejun