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Date: Tue, 24 Apr 2007 20:13:15 +1000
From: Nick Piggin <nickpiggin@yahoo.com.au>
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To: Hisashi Hifumi <hifumi.hisashi@oss.ntt.co.jp>
CC: Hugh Dickins <hugh@veritas.com>, akpm@linux-foundation.org,
       linux-kernel@vger.kernel.org
Subject: Re: [PATCH] mm: PageLRU can be non-atomic bit operation
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Hisashi Hifumi wrote:
> 
> At 11:47 07/04/24, Nick Piggin wrote:
> 
>  >As Hugh points out, we must have atomic ops here, so changing the generic
>  >code to use the __ version is wrong. However if there is a faster way 
> that
>  >i386 can perform the atomic variant, then doing so will speed up the 
> generic
>  >code without breaking other architectures.
>  >
> 
> Do you mean writing page-flags.h specific for i386 so improving generic 
> code
> and without breaking other architectures ?

I meant improving the i386 bitops specific code.

However if there is some variant of operation that is not captured
with the current bitop API, but could provide a useful speedup of
common page flag manipulations, then you might consider extending
the bitop API and making page-flags.h use that new operation.

-- 
SUSE Labs, Novell Inc.