From mboxrd@z Thu Jan  1 00:00:00 1970
From: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Date: Thu, 03 Mar 2005 06:30:28 +0000
Subject: Re: Page fault scalability patch V18: Drop first acquisition of ptl
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To: Nick Piggin <nickpiggin@yahoo.com.au>
Cc: "David S. Miller" <davem@davemloft.net>, Paul Mackerras <paulus@samba.org>, Andrew Morton <akpm@osdl.org>, clameter@sgi.com, Linux Kernel list <linux-kernel@vger.kernel.org>, linux-ia64@vger.kernel.org, Anton Blanchard <anton@samba.org>

On Fri, 2005-03-04 at 04:19 +1100, Nick Piggin wrote:

> You don't want to do that for all architectures, as I said earlier.
> eg. i386 can concurrently set the dirty bit with the MMU (which won't
> honour the lock).
> 
> So you then need an atomic lock, atomic pte operations, and atomic
> unlock where previously you had only the atomic pte operation. This is
> disastrous for performance.

Of course, but I was answering to David about sparc64 which uses
software TLB load :)

Ben.