From patchwork Sat Jun 3 13:10:44 2017 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Christoph Hellwig X-Patchwork-Id: 9764125 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork.web.codeaurora.org (Postfix) with ESMTP id 2579460360 for ; Sat, 3 Jun 2017 13:11:22 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 1776227FA6 for ; Sat, 3 Jun 2017 13:11:22 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 0C90628579; Sat, 3 Jun 2017 13:11:22 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-6.8 required=2.0 tests=BAYES_00,DKIM_SIGNED, RCVD_IN_DNSWL_HI,T_DKIM_INVALID autolearn=ham version=3.3.1 Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 9C11527FA6 for ; Sat, 3 Jun 2017 13:11:21 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751163AbdFCNLU (ORCPT ); Sat, 3 Jun 2017 09:11:20 -0400 Received: from bombadil.infradead.org ([65.50.211.133]:58160 "EHLO bombadil.infradead.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750991AbdFCNLU (ORCPT ); Sat, 3 Jun 2017 09:11:20 -0400 DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=bombadil.20170209; h=References:In-Reply-To:Message-Id: Date:Subject:Cc:To:From:Sender:Reply-To:MIME-Version:Content-Type: Content-Transfer-Encoding:Content-ID:Content-Description:Resent-Date: Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Id: List-Help:List-Unsubscribe:List-Subscribe:List-Post:List-Owner:List-Archive; bh=rORxiDpwZ2Cnca8ZpWpCGYCyIWzhWzMlUTLku6uRIAk=; b=k3v7zaU1wFFvwpM1kEnSVt7nq WAkIM+OpQZ81yZL0uHcSQTZqZi+5/Mw3OdaoXxGP266h/+A4s3vQia4f4PSK65CtAUIEe5iLbYQsg V7FTfSxX15WJ+zuU+utGlwSKDKywTZJfIgadIAmp3mvan9zQI02AtpVVLkVHfaUxFAtXpuZemZ0Tm HYEv+Il4EVhIfaVAcCYZONSPHGjOmLfp9dhaXnx5ZZh8CdyUP9MF5JNCZDT0h7PFw4L74wJgfFXf/ 7MeP8aK+LMmzdw6X1WAIUcbjSAYeDbLDN1CfkQkv2Uohyk3+0kZQ2W1WSsDmu6Kqon+ecUx27q50X 5BH8OaCtA==; Received: from p4ff2fcbf.dip0.t-ipconnect.de ([79.242.252.191] helo=localhost) by bombadil.infradead.org with esmtpsa (Exim 4.87 #1 (Red Hat Linux)) id 1dH8pr-0006JJ-41; Sat, 03 Jun 2017 13:11:19 +0000 From: Christoph Hellwig To: stable@vger.kernel.org Cc: linux-xfs@vger.kernel.org, Brian Foster , "Darrick J . Wong" Subject: [PATCH 04/23] xfs: drop iolock from reclaim context to appease lockdep Date: Sat, 3 Jun 2017 15:10:44 +0200 Message-Id: <20170603131103.23712-5-hch@lst.de> X-Mailer: git-send-email 2.11.0 In-Reply-To: <20170603131103.23712-1-hch@lst.de> References: <20170603131103.23712-1-hch@lst.de> X-SRS-Rewrite: SMTP reverse-path rewritten from by bombadil.infradead.org. See http://www.infradead.org/rpr.html Sender: linux-xfs-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-xfs@vger.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP From: Brian Foster commit 3b4683c294095b5f777c03307ef8c60f47320e12 upstream. Lockdep complains about use of the iolock in inode reclaim context because it doesn't understand that reclaim has the last reference to the inode, and thus an iolock->reclaim->iolock deadlock is not possible. The iolock is technically not necessary in xfs_inactive() and was only added to appease an assert in xfs_free_eofblocks(), which can be called from other non-reclaim contexts. Therefore, just kill the assert and drop the use of the iolock from reclaim context to quiet lockdep. Signed-off-by: Brian Foster Reviewed-by: Darrick J. Wong Signed-off-by: Darrick J. Wong --- fs/xfs/xfs_bmap_util.c | 8 +++----- fs/xfs/xfs_inode.c | 9 +++++---- 2 files changed, 8 insertions(+), 9 deletions(-) diff --git a/fs/xfs/xfs_bmap_util.c b/fs/xfs/xfs_bmap_util.c index 828532ce0adc..cad4e3e2df00 100644 --- a/fs/xfs/xfs_bmap_util.c +++ b/fs/xfs/xfs_bmap_util.c @@ -904,9 +904,9 @@ xfs_can_free_eofblocks(struct xfs_inode *ip, bool force) } /* - * This is called by xfs_inactive to free any blocks beyond eof - * when the link count isn't zero and by xfs_dm_punch_hole() when - * punching a hole to EOF. + * This is called to free any blocks beyond eof. The caller must hold + * IOLOCK_EXCL unless we are in the inode reclaim path and have the only + * reference to the inode. */ int xfs_free_eofblocks( @@ -921,8 +921,6 @@ xfs_free_eofblocks( struct xfs_bmbt_irec imap; struct xfs_mount *mp = ip->i_mount; - ASSERT(xfs_isilocked(ip, XFS_IOLOCK_EXCL)); - /* * Figure out if there are any blocks beyond the end * of the file. If not, then there is nothing to do. diff --git a/fs/xfs/xfs_inode.c b/fs/xfs/xfs_inode.c index 7605d8396596..ec9826c56500 100644 --- a/fs/xfs/xfs_inode.c +++ b/fs/xfs/xfs_inode.c @@ -1906,12 +1906,13 @@ xfs_inactive( * force is true because we are evicting an inode from the * cache. Post-eof blocks must be freed, lest we end up with * broken free space accounting. + * + * Note: don't bother with iolock here since lockdep complains + * about acquiring it in reclaim context. We have the only + * reference to the inode at this point anyways. */ - if (xfs_can_free_eofblocks(ip, true)) { - xfs_ilock(ip, XFS_IOLOCK_EXCL); + if (xfs_can_free_eofblocks(ip, true)) xfs_free_eofblocks(ip); - xfs_iunlock(ip, XFS_IOLOCK_EXCL); - } return; }