Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1760116AbZCPKXO (ORCPT ); Mon, 16 Mar 2009 06:23:14 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1758846AbZCPKW4 (ORCPT ); Mon, 16 Mar 2009 06:22:56 -0400 Received: from bombadil.infradead.org ([18.85.46.34]:49528 "EHLO bombadil.infradead.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755617AbZCPKWy (ORCPT ); Mon, 16 Mar 2009 06:22:54 -0400 Date: Mon, 16 Mar 2009 06:22:53 -0400 From: Christoph Hellwig To: Jens Axboe Cc: linux-kernel@vger.kernel.org, linux-fsdevel@vger.kernel.org, chris.mason@oracle.com, david@fromorbit.com, npiggin@suse.de, linux-mm@kvack.org Subject: Re: [PATCH 2/7] writeback: switch to per-bdi threads for flushing data Message-ID: <20090316102253.GB9510@infradead.org> References: <1236868428-20408-1-git-send-email-jens.axboe@oracle.com> <1236868428-20408-3-git-send-email-jens.axboe@oracle.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1236868428-20408-3-git-send-email-jens.axboe@oracle.com> User-Agent: Mutt/1.5.18 (2008-05-17) 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 Content-Length: 835 Lines: 24 On Thu, Mar 12, 2009 at 03:33:43PM +0100, Jens Axboe wrote: > +static void bdi_kupdated(struct backing_dev_info *bdi) > +{ > + long nr_to_write; > + struct writeback_control wbc = { > + .bdi = bdi, > + .sync_mode = WB_SYNC_NONE, > + .nr_to_write = 0, > + .for_kupdate = 1, > + .range_cyclic = 1, > + }; > + > + sync_supers(); Not directly related to your patch, but can someone explain WTF sync_supers is doing here or in the old kupdated? We're writing back dirty pages from the VM, and for some reason we try to also write back superblocks. This doesn't really make any sense. -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/