From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753370Ab2KUHyx (ORCPT ); Wed, 21 Nov 2012 02:54:53 -0500 Received: from 173-166-109-252-newengland.hfc.comcastbusiness.net ([173.166.109.252]:54807 "EHLO bombadil.infradead.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752126Ab2KUHyw (ORCPT ); Wed, 21 Nov 2012 02:54:52 -0500 Date: Wed, 21 Nov 2012 02:54:35 -0500 From: Christoph Hellwig To: "Darrick J. Wong" Cc: axboe@kernel.dk, lucho@ionkov.net, jack@suse.cz, ericvh@gmail.com, tytso@mit.edu, rminnich@sandia.gov, viro@zeniv.linux.org.uk, martin.petersen@oracle.com, neilb@suse.de, david@fromorbit.com, linux-kernel@vger.kernel.org, linux-fsdevel@vger.kernel.org, adilger.kernel@dilger.ca, bharrosh@panasas.com, jlayton@samba.org, v9fs-developer@lists.sourceforge.net, linux-ext4@vger.kernel.org Subject: Re: [PATCH 1/4] bdi: Track users that require stable page writes Message-ID: <20121121075435.GA16370@infradead.org> References: <20121121020027.10225.43206.stgit@blackbox.djwong.org> <20121121020034.10225.51692.stgit@blackbox.djwong.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20121121020034.10225.51692.stgit@blackbox.djwong.org> User-Agent: Mutt/1.5.21 (2010-09-15) X-SRS-Rewrite: SMTP reverse-path rewritten from by bombadil.infradead.org See http://www.infradead.org/rpr.html Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Tue, Nov 20, 2012 at 06:00:34PM -0800, Darrick J. Wong wrote: > This creates a per-backing-device counter that tracks the number of users which > require pages to be held immutable during writeout. Eventually it will be used > to waive wait_for_page_writeback() if nobody requires stable pages. Why are we going down this stupid route again now? Just let the block device say it needs stable writes and let the VM deal with it.