From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from cuda.sgi.com (cuda2.sgi.com [192.48.176.25]) by oss.sgi.com (8.14.3/8.14.3/SuSE Linux 0.8) with ESMTP id o5SEVxTn029715 for ; Mon, 28 Jun 2010 09:31:59 -0500 Received: from bombadil.infradead.org (localhost [127.0.0.1]) by cuda.sgi.com (Spam Firewall) with ESMTP id 0B5F640D5F1 for ; Mon, 28 Jun 2010 07:34:44 -0700 (PDT) Received: from bombadil.infradead.org (bombadil.infradead.org [18.85.46.34]) by cuda.sgi.com with ESMTP id FuMvHHxYCbw1DdWg for ; Mon, 28 Jun 2010 07:34:44 -0700 (PDT) Received: from hch by bombadil.infradead.org with local (Exim 4.72 #1 (Red Hat Linux)) id 1OTFQ4-0001U7-Mw for xfs@oss.sgi.com; Mon, 28 Jun 2010 14:34:44 +0000 Date: Mon, 28 Jun 2010 10:34:44 -0400 From: Christoph Hellwig Subject: [PATCH] xfs: allow writeback from kswapd Message-ID: <20100628143444.GB5473@infradead.org> MIME-Version: 1.0 Content-Disposition: inline List-Id: XFS Filesystem from SGI List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: xfs-bounces@oss.sgi.com Errors-To: xfs-bounces@oss.sgi.com To: xfs@oss.sgi.com We only need disable I/O from direct or memcg reclaim. Signed-off-by: Christoph Hellwig Index: xfs-dev/fs/xfs/linux-2.6/xfs_aops.c =================================================================== --- xfs-dev.orig/fs/xfs/linux-2.6/xfs_aops.c 2010-06-28 11:57:06.652261386 +0200 +++ xfs-dev/fs/xfs/linux-2.6/xfs_aops.c 2010-06-28 11:59:17.846068204 +0200 @@ -1049,16 +1049,15 @@ xfs_vm_writepage( /* * Refuse to write the page out if we are called from reclaim context. * - * This is primarily to avoid stack overflows when called from deep - * used stacks in random callers for direct reclaim, but disabling - * reclaim for kswap is a nice side-effect as kswapd causes rather - * suboptimal I/O patters, too. + * This avoids stack overflows when called from deeply used stacks in + * random callers for direct reclaim or memcg reclaim. We explicitly + * allow reclaim from kswapd as the stack usage there is relatively low. * * This should really be done by the core VM, but until that happens * filesystems like XFS, btrfs and ext4 have to take care of this * by themselves. */ - if (current->flags & PF_MEMALLOC) + if ((current->flags & (PF_MEMALLOC|PF_KSWAPD)) == PF_MEMALLOC) goto out_fail; /* _______________________________________________ xfs mailing list xfs@oss.sgi.com http://oss.sgi.com/mailman/listinfo/xfs