From patchwork Mon Jan 25 19:17:51 2016 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Jaegeuk Kim X-Patchwork-Id: 8114911 Return-Path: X-Original-To: patchwork-linux-fsdevel@patchwork.kernel.org Delivered-To: patchwork-parsemail@patchwork1.web.kernel.org Received: from mail.kernel.org (mail.kernel.org [198.145.29.136]) by patchwork1.web.kernel.org (Postfix) with ESMTP id 2672F9F440 for ; Mon, 25 Jan 2016 19:17:59 +0000 (UTC) Received: from mail.kernel.org (localhost [127.0.0.1]) by mail.kernel.org (Postfix) with ESMTP id 1E642202E5 for ; Mon, 25 Jan 2016 19:17:58 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id EE2D5201F4 for ; Mon, 25 Jan 2016 19:17:56 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1757557AbcAYTRz (ORCPT ); Mon, 25 Jan 2016 14:17:55 -0500 Received: from mail.kernel.org ([198.145.29.136]:37195 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1757305AbcAYTRy (ORCPT ); Mon, 25 Jan 2016 14:17:54 -0500 Received: from mail.kernel.org (localhost [127.0.0.1]) by mail.kernel.org (Postfix) with ESMTP id 3670C202D1; Mon, 25 Jan 2016 19:17:53 +0000 (UTC) Received: from localhost (107-1-141-74-ip-static.hfc.comcastbusiness.net [107.1.141.74]) (using TLSv1.2 with cipher AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 4593C201F4; Mon, 25 Jan 2016 19:17:52 +0000 (UTC) Date: Mon, 25 Jan 2016 11:17:51 -0800 From: Jaegeuk Kim To: Chao Yu Cc: linux-kernel@vger.kernel.org, linux-fsdevel@vger.kernel.org, linux-f2fs-devel@lists.sourceforge.net Subject: Re: [f2fs-dev] [PATCH 1/2] f2fs: avoid multiple node page writes due to inline_data Message-ID: <20160125191751.GA12233@jaegeuk.gateway> References: <1453580148-61861-1-git-send-email-jaegeuk@kernel.org> <000d01d15754$dca6e6d0$95f4b470$@samsung.com> MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: <000d01d15754$dca6e6d0$95f4b470$@samsung.com> User-Agent: Mutt/1.5.23 (2014-03-12) X-Spam-Status: No, score=-6.9 required=5.0 tests=BAYES_00, RCVD_IN_DNSWL_HI, RP_MATCHES_RCVD, UNPARSEABLE_RELAY autolearn=unavailable version=3.3.1 X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on mail.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP Sender: linux-fsdevel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-fsdevel@vger.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP Hi Chao, On Mon, Jan 25, 2016 at 05:42:40PM +0800, Chao Yu wrote: > Hi Jaegeuk, > > > -----Original Message----- > > From: Jaegeuk Kim [mailto:jaegeuk@kernel.org] > > Sent: Sunday, January 24, 2016 4:16 AM > > To: linux-kernel@vger.kernel.org; linux-fsdevel@vger.kernel.org; > > linux-f2fs-devel@lists.sourceforge.net > > Cc: Jaegeuk Kim > > Subject: [f2fs-dev] [PATCH 1/2] f2fs: avoid multiple node page writes due to inline_data > > > > The sceanrio is: > > 1. create fully node blocks > > 2. flush node blocks > > 3. write inline_data for all the node blocks again > > 4. flush node blocks redundantly > > > > Signed-off-by: Jaegeuk Kim > > --- > > fs/f2fs/data.c | 14 +++++++++++--- > > 1 file changed, 11 insertions(+), 3 deletions(-) > > > > diff --git a/fs/f2fs/data.c b/fs/f2fs/data.c > > index 8d0d9ec..011456e 100644 > > --- a/fs/f2fs/data.c > > +++ b/fs/f2fs/data.c > > @@ -1622,14 +1622,22 @@ static int f2fs_write_end(struct file *file, > > > > trace_f2fs_write_end(inode, pos, len, copied); > > > > - set_page_dirty(page); > > - > > if (pos + copied > i_size_read(inode)) { > > i_size_write(inode, pos + copied); > > mark_inode_dirty(inode); > > - update_inode_page(inode); > > } > > > > + if (f2fs_has_inline_data(inode) && > > + is_inode_flag_set(F2FS_I(inode), FI_DATA_EXIST)) { > > + int err = f2fs_write_inline_data(inode, page); > > Oh, I'm sure this can fix that issue, but IMO: > a) this implementation has side-effect, it triggers inline data copying > between data page and node page whenever user write inline datas, so if > user updates inline data frequently, write-through approach would cause > memory copy overhead. Agreed. > b) inline storm should be a rare case, as we didn't get any report about > problem for long time until Dave's, and write_end is a hot path, I think > it's better to be cautious to change our inline data cache policy for > fixing a rare issue in hot path. > > What about delaying the merge operation? like: > 1) as I proposed before, merging inline page into inode page when > detecting free_sections <= (node_secs + 2 * dent_secs + inline_secs). > 2) merge inline page into inode page before writeback inode page in > sync_node_pages. Okay, I'm thinking more general way where we can get rid of every inlien_data write when we flush node pages. I've been testing this patch. From ebddf607c64da691fef08cf68a8ecadafd5d896b Mon Sep 17 00:00:00 2001 From: Jaegeuk Kim Date: Mon, 25 Jan 2016 05:57:05 -0800 Subject: [PATCH] f2fs: avoid multiple node page writes due to inline_data The sceanrio is: 1. create fully node blocks 2. flush node blocks 3. write inline_data for all the node blocks again 4. flush node blocks redundantly So, this patch tries to flush inline_data when flushing node blocks. Signed-off-by: Jaegeuk Kim --- fs/f2fs/data.c | 1 + fs/f2fs/inline.c | 2 ++ fs/f2fs/node.c | 35 +++++++++++++++++++++++++++++++++++ fs/f2fs/node.h | 15 +++++++++++++++ 4 files changed, 53 insertions(+) diff --git a/fs/f2fs/data.c b/fs/f2fs/data.c index 6925c10..9043ecf 100644 --- a/fs/f2fs/data.c +++ b/fs/f2fs/data.c @@ -1464,6 +1464,7 @@ restart: if (pos + len <= MAX_INLINE_DATA) { read_inline_data(page, ipage); set_inode_flag(F2FS_I(inode), FI_DATA_EXIST); + set_inline_node(ipage); sync_inode_page(&dn); } else { err = f2fs_convert_inline_page(&dn, page); diff --git a/fs/f2fs/inline.c b/fs/f2fs/inline.c index 8df13e5..fc4d298 100644 --- a/fs/f2fs/inline.c +++ b/fs/f2fs/inline.c @@ -159,6 +159,7 @@ no_update: /* clear inline data and flag after data writeback */ truncate_inline_inode(dn->inode_page, 0); + clear_inline_node(dn->inode_page); clear_out: stat_dec_inline_inode(dn->inode); f2fs_clear_inline_inode(dn->inode); @@ -233,6 +234,7 @@ int f2fs_write_inline_data(struct inode *inode, struct page *page) set_inode_flag(F2FS_I(inode), FI_DATA_EXIST); sync_inode_page(&dn); + clear_inline_node(dn.inode_page); f2fs_put_dnode(&dn); return 0; } diff --git a/fs/f2fs/node.c b/fs/f2fs/node.c index 23b800d..1c5023e 100644 --- a/fs/f2fs/node.c +++ b/fs/f2fs/node.c @@ -1154,6 +1154,33 @@ void sync_inode_page(struct dnode_of_data *dn) dn->node_changed = ret ? true: false; } +static void flush_inline_data(struct f2fs_sb_info *sbi, nid_t ino) +{ + struct inode *inode; + struct page *page; + + inode = ilookup(sbi->sb, ino); + if (!inode) + return; + + page = find_lock_page(inode->i_mapping, 0); + if (!page) + goto iput_out; + + if (!PageDirty(page)) + goto put_page_out; + + if (!clear_page_dirty_for_io(page)) + goto put_page_out; + + if (!f2fs_write_inline_data(inode, page)) + inode_dec_dirty_pages(inode); +put_page_out: + f2fs_put_page(page, 1); +iput_out: + iput(inode); +} + int sync_node_pages(struct f2fs_sb_info *sbi, nid_t ino, struct writeback_control *wbc) { @@ -1221,6 +1248,14 @@ continue_unlock: goto continue_unlock; } + /* flush inline_data */ + if (!ino && is_inline_node(page)) { + clear_inline_node(page); + unlock_page(page); + flush_inline_data(sbi, ino_of_node(page)); + continue; + } + if (!clear_page_dirty_for_io(page)) goto continue_unlock; diff --git a/fs/f2fs/node.h b/fs/f2fs/node.h index 23bd992..1f4f9d4 100644 --- a/fs/f2fs/node.h +++ b/fs/f2fs/node.h @@ -379,6 +379,21 @@ static inline int is_node(struct page *page, int type) #define is_fsync_dnode(page) is_node(page, FSYNC_BIT_SHIFT) #define is_dent_dnode(page) is_node(page, DENT_BIT_SHIFT) +static inline int is_inline_node(struct page *page) +{ + return PageChecked(page); +} + +static inline void set_inline_node(struct page *page) +{ + SetPageChecked(page); +} + +static inline void clear_inline_node(struct page *page) +{ + ClearPageChecked(page); +} + static inline void set_cold_node(struct inode *inode, struct page *page) { struct f2fs_node *rn = F2FS_NODE(page);