From patchwork Thu Nov 1 07:58:21 2012 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Darrick Wong X-Patchwork-Id: 196093 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@bilbo.ozlabs.org Received: from merlin.infradead.org (merlin.infradead.org [IPv6:2001:4978:20e::2]) (using TLSv1 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (Client did not present a certificate) by ozlabs.org (Postfix) with ESMTPS id 7BEAC2C02BC for ; Thu, 1 Nov 2012 19:30:12 +1100 (EST) Received: from localhost ([::1] helo=merlin.infradead.org) by merlin.infradead.org with esmtp (Exim 4.76 #1 (Red Hat Linux)) id 1TTq8y-000802-Q4; Thu, 01 Nov 2012 08:28:52 +0000 Received: from aserp1050.oracle.com ([141.146.126.70]) by merlin.infradead.org with esmtps (Exim 4.76 #1 (Red Hat Linux)) id 1TTq8v-0007zc-5O; Thu, 01 Nov 2012 08:28:49 +0000 Received: from aserp1040.oracle.com (aserp1040.oracle.com [141.146.126.69]) by aserp1050.oracle.com (Sentrion-MTA-4.2.2/Sentrion-MTA-4.2.2) with ESMTP id qA17wm19005171 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-SHA bits=256 verify=OK); Thu, 1 Nov 2012 07:58:48 GMT Received: from ucsinet21.oracle.com (ucsinet21.oracle.com [156.151.31.93]) by aserp1040.oracle.com (Sentrion-MTA-4.2.2/Sentrion-MTA-4.2.2) with ESMTP id qA17wRxK014079 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-SHA bits=256 verify=OK); Thu, 1 Nov 2012 07:58:28 GMT Received: from acsmt357.oracle.com (acsmt357.oracle.com [141.146.40.157]) by ucsinet21.oracle.com (8.14.4+Sun/8.14.4) with ESMTP id qA17wOo1023161 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-SHA bits=256 verify=NO); Thu, 1 Nov 2012 07:58:25 GMT Received: from abhmt106.oracle.com (abhmt106.oracle.com [141.146.116.58]) by acsmt357.oracle.com (8.12.11.20060308/8.12.11) with ESMTP id qA17wO3P005914; Thu, 1 Nov 2012 02:58:24 -0500 Received: from localhost (/67.171.138.228) by default (Oracle Beehive Gateway v4.0) with ESMTP ; Thu, 01 Nov 2012 00:58:24 -0700 Subject: [PATCH 2/3] mm: Only enforce stable page writes if the backing device requires it To: axboe@kernel.dk, lucho@ionkov.net, tytso@mit.edu, sage@inktank.com, darrick.wong@oracle.com, ericvh@gmail.com, mfasheh@suse.com, dedekind1@gmail.com, adrian.hunter@intel.com, dhowells@redhat.com, sfrench@samba.org, jlbec@evilplan.org, rminnich@sandia.gov From: "Darrick J. Wong" Date: Thu, 01 Nov 2012 00:58:21 -0700 Message-ID: <20121101075821.16153.38301.stgit@blackbox.djwong.org> In-Reply-To: <20121101075805.16153.64714.stgit@blackbox.djwong.org> References: <20121101075805.16153.64714.stgit@blackbox.djwong.org> User-Agent: StGit/0.15 MIME-Version: 1.0 X-Source-IP: aserp1040.oracle.com [141.146.126.69] X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20121101_042849_370187_FEB72E54 X-CRM114-Status: GOOD ( 14.13 ) X-Spam-Score: 0.4 (/) X-Spam-Report: SpamAssassin version 3.3.2 on merlin.infradead.org summary: Content analysis details: (0.4 points) pts rule name description ---- ---------------------- -------------------------------------------------- 3.0 KHOP_BIG_TO_CC Sent to 10+ recipients instaed of Bcc or a list -0.0 SPF_PASS SPF: sender matches SPF record -0.7 RP_MATCHES_RCVD Envelope sender domain matches handover relay domain -1.9 BAYES_00 BODY: Bayes spam probability is 0 to 1% [score: 0.0000] 0.0 UNPARSEABLE_RELAY Informational: message has unparseable relay lines Cc: linux-cifs@vger.kernel.org, jack@suse.cz, martin.petersen@oracle.com, neilb@suse.de, david@fromorbit.com, linux-kernel@vger.kernel.org, linux-mm@kvack.org, linux-mtd@lists.infradead.org, bharrosh@panasas.com, linux-fsdevel@vger.kernel.org, v9fs-developer@lists.sourceforge.net, ceph-devel@vger.kernel.org, linux-ext4@vger.kernel.org, linux-afs@lists.infradead.org, ocfs2-devel@oss.oracle.com X-BeenThere: linux-mtd@lists.infradead.org X-Mailman-Version: 2.1.14 Precedence: list List-Id: Linux MTD discussion mailing list List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: linux-mtd-bounces@lists.infradead.org Errors-To: linux-mtd-bounces+incoming=patchwork.ozlabs.org@lists.infradead.org Create a helper function to check if a backing device requires stable page writes and, if so, performs the necessary wait. Then, make it so that all points in the memory manager that handle making pages writable use the helper function. This should provide stable page write support to most filesystems, while eliminating unnecessary waiting for devices that don't require the feature. Signed-off-by: Darrick J. Wong --- fs/buffer.c | 2 +- fs/ext4/inode.c | 2 +- include/linux/pagemap.h | 1 + mm/filemap.c | 3 ++- mm/page-writeback.c | 11 +++++++++++ 5 files changed, 16 insertions(+), 3 deletions(-) diff --git a/fs/buffer.c b/fs/buffer.c index b5f0442..cac3007 100644 --- a/fs/buffer.c +++ b/fs/buffer.c @@ -2334,7 +2334,7 @@ int __block_page_mkwrite(struct vm_area_struct *vma, struct vm_fault *vmf, if (unlikely(ret < 0)) goto out_unlock; set_page_dirty(page); - wait_on_page_writeback(page); + wait_on_stable_page_write(page); return 0; out_unlock: unlock_page(page); diff --git a/fs/ext4/inode.c b/fs/ext4/inode.c index b3c243b..948d68a 100644 --- a/fs/ext4/inode.c +++ b/fs/ext4/inode.c @@ -4814,7 +4814,7 @@ int ext4_page_mkwrite(struct vm_area_struct *vma, struct vm_fault *vmf) if (!walk_page_buffers(NULL, page_buffers(page), 0, len, NULL, ext4_bh_unmapped)) { /* Wait so that we don't change page under IO */ - wait_on_page_writeback(page); + wait_on_stable_page_write(page); ret = VM_FAULT_LOCKED; goto out; } diff --git a/include/linux/pagemap.h b/include/linux/pagemap.h index e42c762..c28da25 100644 --- a/include/linux/pagemap.h +++ b/include/linux/pagemap.h @@ -398,6 +398,7 @@ static inline void wait_on_page_writeback(struct page *page) } extern void end_page_writeback(struct page *page); +void wait_on_stable_page_write(struct page *page); /* * Add an arbitrary waiter to a page's wait queue diff --git a/mm/filemap.c b/mm/filemap.c index 83efee7..ee46141 100644 --- a/mm/filemap.c +++ b/mm/filemap.c @@ -1728,6 +1728,7 @@ int filemap_page_mkwrite(struct vm_area_struct *vma, struct vm_fault *vmf) * see the dirty page and writeprotect it again. */ set_page_dirty(page); + wait_on_stable_page_write(page); out: sb_end_pagefault(inode->i_sb); return ret; @@ -2274,7 +2275,7 @@ repeat: return NULL; } found: - wait_on_page_writeback(page); + wait_on_stable_page_write(page); return page; } EXPORT_SYMBOL(grab_cache_page_write_begin); diff --git a/mm/page-writeback.c b/mm/page-writeback.c index 830893b..916dae1 100644 --- a/mm/page-writeback.c +++ b/mm/page-writeback.c @@ -2275,3 +2275,14 @@ int mapping_tagged(struct address_space *mapping, int tag) return radix_tree_tagged(&mapping->page_tree, tag); } EXPORT_SYMBOL(mapping_tagged); + +void wait_on_stable_page_write(struct page *page) +{ + struct backing_dev_info *bdi = page->mapping->backing_dev_info; + + if (!bdi_cap_stable_pages_required(bdi)) + return; + + wait_on_page_writeback(page); +} +EXPORT_SYMBOL_GPL(wait_on_stable_page_write);