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Subject: Re: [patch] powerpc: hash lock use lock bitops
From: Benjamin Herrenschmidt <benh@kernel.crashing.org>
To: Nick Piggin <npiggin@suse.de>
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Date: Tue, 20 Nov 2007 17:08:24 +1100
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Cc: linuxppc-dev@ozlabs.org, Paul Mackerras <paulus@samba.org>,
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On Tue, 2007-11-20 at 06:09 +0100, Nick Piggin wrote:
> This isn't a bugfix, but may help performance slightly...
> 
> --
> powerpc 64-bit hash pte lock bit is an actual lock, so it can take advantage
> of lock bitops for slightly more optimal memory barriers (can avoid an lwsync
> in the trylock).
> 
> Signed-off-by: Nick Piggin <npiggin@suse.de>
> Acked-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
> ---

Looks nice, I'll try it out on a G5 and let you know.

Cheers,
Ben.