From patchwork Mon Sep 24 11:44:18 2012 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Dmitry Monakhov X-Patchwork-Id: 186382 Return-Path: X-Original-To: patchwork-incoming@ozlabs.org Delivered-To: patchwork-incoming@ozlabs.org Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by ozlabs.org (Postfix) with ESMTP id 77DE42C0086 for ; Mon, 24 Sep 2012 21:44:48 +1000 (EST) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754530Ab2IXLoq (ORCPT ); Mon, 24 Sep 2012 07:44:46 -0400 Received: from mail-lb0-f174.google.com ([209.85.217.174]:62207 "EHLO mail-lb0-f174.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754735Ab2IXLom (ORCPT ); Mon, 24 Sep 2012 07:44:42 -0400 Received: by mail-lb0-f174.google.com with SMTP id gj3so6549540lbb.19 for ; Mon, 24 Sep 2012 04:44:42 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20120113; h=sender:from:to:cc:subject:date:message-id:x-mailer:in-reply-to :references; bh=fhzIf/i4ST9OJFOD9hUVWXNNfO8o0MK6tC2r/n1uYNY=; b=w2aUNpQbv3sXMLQdXmFelnTIGOlI62AkhaFTnxZMRk9aBvvoWx1Yp/4qgkcEIRJVG2 DPUnUDx/RsJl1vcUMIkdCWgS2Ml0MTYb3Iyng6R7WxUxDruUHCIn1LlmY+Cmc1uD2scl L4E3tRk8tupwdlmm0sVwi1vgxt4ikgo7suE1ivfG1RpR2pv0IWZzz0r2CoQtyDjMvy8B fNuIurMfCuI7gdVmiRPOc1bPMGlbZ6US8ijRj+vNAMY+AQfSoaKvf+5hxGFbid9kp2WK lvMltMOh95NyMkVJaK3sxu5kVT3LNnvC6ALdY88bAuOEaZOcz6ZNNBSwj+09+j7bm5of Gwcw== Received: by 10.112.46.10 with SMTP id r10mr4172458lbm.13.1348487081953; Mon, 24 Sep 2012 04:44:41 -0700 (PDT) Received: from smtp.gmail.com (swsoft-msk-nat.sw.ru. [195.214.232.10]) by mx.google.com with ESMTPS id u5sm4234093lbg.8.2012.09.24.04.44.40 (version=TLSv1/SSLv3 cipher=OTHER); Mon, 24 Sep 2012 04:44:41 -0700 (PDT) From: Dmitry Monakhov To: linux-ext4@vger.kernel.org Cc: tytso@mit.edu, jack@suse.cz, lczerner@redhat.com, Dmitry Monakhov Subject: [PATCH 08/10] ext4: endless truncate due to nonlocked dio readers V2 Date: Mon, 24 Sep 2012 15:44:18 +0400 Message-Id: <1348487060-19598-9-git-send-email-dmonakhov@openvz.org> X-Mailer: git-send-email 1.7.7.6 In-Reply-To: <1348487060-19598-1-git-send-email-dmonakhov@openvz.org> References: <1348487060-19598-1-git-send-email-dmonakhov@openvz.org> Sender: linux-ext4-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-ext4@vger.kernel.org If we have enough aggressive DIO readers, truncate and other dio waiters will wait forever inside inode_dio_wait(). It is reasonable to disable nonlock DIO read optimization during truncate. Signed-off-by: Dmitry Monakhov --- fs/ext4/inode.c | 8 ++++++-- 1 files changed, 6 insertions(+), 2 deletions(-) diff --git a/fs/ext4/inode.c b/fs/ext4/inode.c index 32e9701..d3f86e7 100644 --- a/fs/ext4/inode.c +++ b/fs/ext4/inode.c @@ -4330,9 +4330,13 @@ int ext4_setattr(struct dentry *dentry, struct iattr *attr) if (attr->ia_valid & ATTR_SIZE) { if (attr->ia_size != inode->i_size) { truncate_setsize(inode, attr->ia_size); - /* Inode size will be reduced, wait for dio in flight */ - if (orphan) + /* Inode size will be reduced, wait for dio in flight. + * Temproraly disable unlocked DIO to prevent livelock */ + if (orphan) { + ext4_inode_block_unlocked_dio(inode); inode_dio_wait(inode); + ext4_inode_resume_unlocked_dio(inode); + } } ext4_truncate(inode); }