From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751136AbWFBCVn (ORCPT ); Thu, 1 Jun 2006 22:21:43 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1751138AbWFBCVn (ORCPT ); Thu, 1 Jun 2006 22:21:43 -0400 Received: from smtp110.mail.mud.yahoo.com ([209.191.85.220]:19809 "HELO smtp110.mail.mud.yahoo.com") by vger.kernel.org with SMTP id S1751136AbWFBCVm (ORCPT ); Thu, 1 Jun 2006 22:21:42 -0400 DomainKey-Signature: a=rsa-sha1; q=dns; c=nofws; s=s1024; d=yahoo.com.au; h=Received:Message-ID:Date:From:User-Agent:X-Accept-Language:MIME-Version:To:CC:Subject:References:In-Reply-To:Content-Type:Content-Transfer-Encoding; b=2gu4TPnRmMBz3ZCap5ij0VJR5GctPJ/JO7zaMbFN779XVj03mrfu7PJCOg5qGpdKCGHm9zPfPbuat9YnBXRnENYkWZihLCuFvWwLC7IUfESy+ysXVEbI57gmthc/oV4ouXstPiqkPK2Sb3Ff1o7fSWdVCqLc4u39IEWedoGdkLw= ; Message-ID: <447FA0AE.9050002@yahoo.com.au> Date: Fri, 02 Jun 2006 12:21:34 +1000 From: Nick Piggin User-Agent: Mozilla/5.0 (X11; U; Linux i686; en-US; rv:1.7.12) Gecko/20051007 Debian/1.7.12-1 X-Accept-Language: en MIME-Version: 1.0 To: Linus Torvalds CC: linux-kernel@vger.kernel.org, axboe@suse.de Subject: Re: [rfc][patch] remove racy sync_page? References: <447AC011.8050708@yahoo.com.au> <20060529121556.349863b8.akpm@osdl.org> <447B8CE6.5000208@yahoo.com.au> <20060529183201.0e8173bc.akpm@osdl.org> <447BB3FD.1070707@yahoo.com.au> <447BD31E.7000503@yahoo.com.au> <447BD63D.2080900@yahoo.com.au> <447CE43A.6030700@yahoo.com.au> <447D9A41.8040601@yahoo.com.au> <447DAEDE.5070305@yahoo.com.au> <447DB765.6030702@yahoo.com.au> <447DC22C.5070503@yahoo.com.au> In-Reply-To: Content-Type: text/plain; charset=us-ascii; format=flowed Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Linus Torvalds wrote: > > On Thu, 1 Jun 2006, Nick Piggin wrote: > >>I keep telling you. Put the unplug after submission of IO. Not before >>waiting for IO. > > > And that's exactly where we have the lock_page(). In some cases. > > And you ignored the list of _requirements_ I had, so you just missed the > other place you _have_ to have the unplug, namely in the "found a page > that was not yet up-to-date" case (look for the other lock_page()). I know you have to unplug there. I didn't ignore anything. Where is the problem? > Because the person who started the IO might be off doing something else, > and may not be unplugging now (or ever, in the case of readahead). > > In other words, when you start arguing, at least read my emails. Your > suggestion would have introduced a bug by not waiting on that other place. No. I'm saying the "person" who started IO _could_ be the one unplugging. Always. -- SUSE Labs, Novell Inc. Send instant messages to your online friends http://au.messenger.yahoo.com