From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756319AbYHEErP (ORCPT ); Tue, 5 Aug 2008 00:47:15 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1753070AbYHEErA (ORCPT ); Tue, 5 Aug 2008 00:47:00 -0400 Received: from smtp102.mail.mud.yahoo.com ([209.191.85.212]:41892 "HELO smtp102.mail.mud.yahoo.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with SMTP id S1752879AbYHEEq7 (ORCPT ); Tue, 5 Aug 2008 00:46:59 -0400 DomainKey-Signature: a=rsa-sha1; q=dns; c=nofws; s=s1024; d=yahoo.com.au; h=Received:X-YMail-OSG:X-Yahoo-Newman-Property:From:To:Subject:Date:User-Agent:Cc:References:In-Reply-To:MIME-Version:Content-Type:Content-Transfer-Encoding:Content-Disposition:Message-Id; b=jOELNvxaJPMQLnWCwzOZAjCn07rAKCVSOeWR0nEzoH6h53/IgCE4jah21TEmf5E2t6zAKgMrrAEIC3/ai6v2tBELrXmUV0YM8fcg4JUx4Oz/oOtaDjafvRDofIcdA146a9wyCxA12EAa2OoIBFsyPp6/I0SHSN6L3sqFWFFsVEA= ; X-YMail-OSG: .MaYj4YVM1moX8aSjJ52Lcc0jULqJeOFGC0DvamMZK6EvPfhkwBk3BHC3DzbUWGdJXj8HSJDYYsxscobxahs_I.Yiu2er160vmZcAaq4fV9MxKz4nWbyLEL1xdQm_5kRUpHpxzDcw2i41OHuw5jdn3pl X-Yahoo-Newman-Property: ymail-3 From: Nick Piggin To: Linus Torvalds Subject: Re: Switching TestSetPageLocked to trylock_page Date: Tue, 5 Aug 2008 14:46:52 +1000 User-Agent: KMail/1.9.5 Cc: Andrew Morton , Linux Kernel Mailing List References: <200807311726.51816.nickpiggin@yahoo.com.au> <200808051341.53282.nickpiggin@yahoo.com.au> In-Reply-To: MIME-Version: 1.0 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: 7bit Content-Disposition: inline Message-Id: <200808051446.52538.nickpiggin@yahoo.com.au> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Tuesday 05 August 2008 14:25, Linus Torvalds wrote: > On Tue, 5 Aug 2008, Nick Piggin wrote: > > The part that helps x86 is another patch further down my stack, which > > can avoid looking at the hashed page waitqueue at unlock_page-time. > > Basically this eliminates the entire page waitqueue from the cache > > footprint of fastpath workloads where the lock is uncontended (often: > > page faulting, write(2), writeout etc). > > Hmm. Tell me more. Contention bit? Exactly. This is around the latest one online from a quick google: http://www.kernel.org/pub/linux/kernel/people/npiggin/patches/lock-bitops/2.6.22-rc4/mm-unlock-speedup.patch