From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-2.6 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,MAILING_LIST_MULTI,SPF_PASS,T_DKIMWL_WL_HIGH,USER_AGENT_MUTT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id B1926C46464 for ; Fri, 10 Aug 2018 18:56:45 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 6274622454 for ; Fri, 10 Aug 2018 18:56:45 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=kernel.org header.i=@kernel.org header.b="yk4/xcKx" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 6274622454 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=kernel.org Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727140AbeHJV1s (ORCPT ); Fri, 10 Aug 2018 17:27:48 -0400 Received: from mail.kernel.org ([198.145.29.99]:55326 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726162AbeHJV1s (ORCPT ); Fri, 10 Aug 2018 17:27:48 -0400 Received: from localhost (unknown [104.132.1.88]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 41F552244C; Fri, 10 Aug 2018 18:56:41 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1533927401; bh=iDXJJkV2NP1DhfYLVuyxoipdp2m6DJhvEJXpAV/8FAc=; h=Date:From:To:Subject:References:In-Reply-To:From; b=yk4/xcKxSe0aMIJliTQxWe7qnyG65oPBkRYG8Txj8hlCM44kK1odpqx6HBg6f0epU j/g414v2nQYVNvoHZuIqwUzumF6zMGr30ldVi0xMyV1zTxQoRLw8QSkwU8Zp6wJVsi mwXuVj50jGc2QCEZjIIKqek/b3t23EMiAjzSjaBw= Date: Fri, 10 Aug 2018 11:56:40 -0700 From: Jaegeuk Kim To: linux-kernel@vger.kernel.org, linux-f2fs-devel@lists.sourceforge.net Subject: Re: [f2fs-dev] [PATCH v3] f2fs: fix performance issue observed with multi-thread sequential read Message-ID: <20180810185640.GA63079@jaegeuk-macbookpro.roam.corp.google.com> References: <20180810023758.46974-1-jaegeuk@kernel.org> <20180810024859.GA48219@jaegeuk-macbookpro.roam.corp.google.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20180810024859.GA48219@jaegeuk-macbookpro.roam.corp.google.com> User-Agent: Mutt/1.8.2 (2017-04-18) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org This reverts the commit - "b93f771 - f2fs: remove writepages lock" to fix the drop in sequential read throughput. Test: ./tiotest -t 32 -d /data/tio_tmp -f 32 -b 524288 -k 1 -k 3 -L device: UFS Before - read throughput: 185 MB/s total read requests: 85177 (of these ~80000 are 4KB size requests). total write requests: 2546 (of these ~2208 requests are written in 512KB). After - read throughput: 758 MB/s total read requests: 2417 (of these ~2042 are 512KB reads). total write requests: 2701 (of these ~2034 requests are written in 512KB). Signed-off-by: Sahitya Tummala Signed-off-by: Jaegeuk Kim --- Changelog from v2: - fix deadlock in f2fs_gc fs/f2fs/data.c | 9 +++++++++ fs/f2fs/f2fs.h | 1 + fs/f2fs/super.c | 1 + 3 files changed, 11 insertions(+) diff --git a/fs/f2fs/data.c b/fs/f2fs/data.c index 45f043ee48bd..9f0149cdeed8 100644 --- a/fs/f2fs/data.c +++ b/fs/f2fs/data.c @@ -2132,6 +2132,7 @@ static int __f2fs_write_data_pages(struct address_space *mapping, struct f2fs_sb_info *sbi = F2FS_I_SB(inode); struct blk_plug plug; int ret; + bool locked = false; /* deal with chardevs and other special file */ if (!mapping->a_ops->writepage) @@ -2162,10 +2163,18 @@ static int __f2fs_write_data_pages(struct address_space *mapping, else if (atomic_read(&sbi->wb_sync_req[DATA])) goto skip_write; + if (!S_ISDIR(inode->i_mode)) { + mutex_lock(&sbi->writepages); + locked = true; + } + blk_start_plug(&plug); ret = f2fs_write_cache_pages(mapping, wbc, io_type); blk_finish_plug(&plug); + if (locked) + mutex_unlock(&sbi->writepages); + if (wbc->sync_mode == WB_SYNC_ALL) atomic_dec(&sbi->wb_sync_req[DATA]); /* diff --git a/fs/f2fs/f2fs.h b/fs/f2fs/f2fs.h index b1c127d8383b..29bbc55cbc0b 100644 --- a/fs/f2fs/f2fs.h +++ b/fs/f2fs/f2fs.h @@ -1133,6 +1133,7 @@ struct f2fs_sb_info { struct rw_semaphore sb_lock; /* lock for raw super block */ int valid_super_block; /* valid super block no */ unsigned long s_flag; /* flags for sbi */ + struct mutex writepages; /* mutex for writepages() */ #ifdef CONFIG_BLK_DEV_ZONED unsigned int blocks_per_blkz; /* F2FS blocks per zone */ diff --git a/fs/f2fs/super.c b/fs/f2fs/super.c index be41dbd7b261..53d70b64fea1 100644 --- a/fs/f2fs/super.c +++ b/fs/f2fs/super.c @@ -2842,6 +2842,7 @@ static int f2fs_fill_super(struct super_block *sb, void *data, int silent) /* init f2fs-specific super block info */ sbi->valid_super_block = valid_super_block; mutex_init(&sbi->gc_mutex); + mutex_init(&sbi->writepages); mutex_init(&sbi->cp_mutex); init_rwsem(&sbi->node_write); init_rwsem(&sbi->node_change); -- 2.17.0.441.gb46fe60e1d-goog