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=-9.3 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_PASS,URIBL_BLOCKED,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 64BCCECE562 for ; Tue, 18 Sep 2018 02:02:31 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id E24C6214C5 for ; Tue, 18 Sep 2018 02:02:30 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=kernel.org header.i=@kernel.org header.b="v76px1sf" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org E24C6214C5 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 S1728517AbeIRHch (ORCPT ); Tue, 18 Sep 2018 03:32:37 -0400 Received: from mail.kernel.org ([198.145.29.99]:47476 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725807AbeIRHch (ORCPT ); Tue, 18 Sep 2018 03:32:37 -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 610D1214AB; Tue, 18 Sep 2018 02:02:27 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1537236147; bh=5As9U8hna7ixRnw9Otig7S/O33kYsiNmx2NsLIgi/fA=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=v76px1sfWxbhry2rcEtLvxHBDWLWAysKtQJXbrFJ84WdTGggKUqA8+ujXVmvpecGm eogTS5JHeCYS2GHPbiiG0/3HOlIPOUtpbsVIBevnnwYU3I1KzIyBsruAxiNc1tRyG6 ekzIFxamWzR4k1vM0WzEEOkVEubv4dp2E0FzLurM= Date: Mon, 17 Sep 2018 19:02:26 -0700 From: Jaegeuk Kim To: Chao Yu Cc: Chao Yu , linux-f2fs-devel@lists.sourceforge.net, linux-kernel@vger.kernel.org Subject: Re: [PATCH v3] f2fs: submit cached bio to avoid endless PageWriteback Message-ID: <20180918020226.GA83471@jaegeuk-macbookpro.roam.corp.google.com> References: <20180912234053.8761-1-chao@kernel.org> <20180918010442.GA79604@jaegeuk-macbookpro.roam.corp.google.com> <3ca1e04f-0929-2ab3-2112-4fa22915be50@huawei.com> <20180918013743.GE79604@jaegeuk-macbookpro.roam.corp.google.com> <8b1571fa-ef41-4ab3-187c-d6caf7a2ebe1@huawei.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <8b1571fa-ef41-4ab3-187c-d6caf7a2ebe1@huawei.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 On 09/18, Chao Yu wrote: > On 2018/9/18 9:37, Jaegeuk Kim wrote: > > On 09/18, Chao Yu wrote: > >> On 2018/9/18 9:04, Jaegeuk Kim wrote: > >>> On 09/13, Chao Yu wrote: > >>>> From: Chao Yu > >>>> > >>>> When migrating encrypted block from background GC thread, we only add > >>>> them into f2fs inner bio cache, but forget to submit the cached bio, it > >>>> may cause potential deadlock when we are waiting page writebacked, fix > >>>> it. > >>>> > >>>> Signed-off-by: Chao Yu > >>>> --- > >>>> v3: > >>>> clean up codes suggested by Jaegeuk. > >>>> fs/f2fs/f2fs.h | 2 +- > >>>> fs/f2fs/gc.c | 71 +++++++++++++++++++++++++++++++++++--------------- > >>>> fs/f2fs/node.c | 13 ++++++--- > >>>> 3 files changed, 61 insertions(+), 25 deletions(-) > >>>> > >>>> diff --git a/fs/f2fs/f2fs.h b/fs/f2fs/f2fs.h > >>>> index b676b82312e0..917b2ca76aac 100644 > >>>> --- a/fs/f2fs/f2fs.h > >>>> +++ b/fs/f2fs/f2fs.h > >>>> @@ -2869,7 +2869,7 @@ struct page *f2fs_new_node_page(struct dnode_of_data *dn, unsigned int ofs); > >>>> void f2fs_ra_node_page(struct f2fs_sb_info *sbi, nid_t nid); > >>>> struct page *f2fs_get_node_page(struct f2fs_sb_info *sbi, pgoff_t nid); > >>>> struct page *f2fs_get_node_page_ra(struct page *parent, int start); > >>>> -void f2fs_move_node_page(struct page *node_page, int gc_type); > >>>> +int f2fs_move_node_page(struct page *node_page, int gc_type); > >>>> int f2fs_fsync_node_pages(struct f2fs_sb_info *sbi, struct inode *inode, > >>>> struct writeback_control *wbc, bool atomic, > >>>> unsigned int *seq_id); > >>>> diff --git a/fs/f2fs/gc.c b/fs/f2fs/gc.c > >>>> index a4c1a419611d..f57622cfe058 100644 > >>>> --- a/fs/f2fs/gc.c > >>>> +++ b/fs/f2fs/gc.c > >>>> @@ -461,7 +461,7 @@ static int check_valid_map(struct f2fs_sb_info *sbi, > >>>> * On validity, copy that node with cold status, otherwise (invalid node) > >>>> * ignore that. > >>>> */ > >>>> -static void gc_node_segment(struct f2fs_sb_info *sbi, > >>>> +static int gc_node_segment(struct f2fs_sb_info *sbi, > >>>> struct f2fs_summary *sum, unsigned int segno, int gc_type) > >>>> { > >>>> struct f2fs_summary *entry; > >>>> @@ -469,6 +469,7 @@ static void gc_node_segment(struct f2fs_sb_info *sbi, > >>>> int off; > >>>> int phase = 0; > >>>> bool fggc = (gc_type == FG_GC); > >>>> + int submitted = 0; > >>>> > >>>> start_addr = START_BLOCK(sbi, segno); > >>>> > >>>> @@ -482,10 +483,11 @@ static void gc_node_segment(struct f2fs_sb_info *sbi, > >>>> nid_t nid = le32_to_cpu(entry->nid); > >>>> struct page *node_page; > >>>> struct node_info ni; > >>>> + int err; > >>>> > >>>> /* stop BG_GC if there is not enough free sections. */ > >>>> if (gc_type == BG_GC && has_not_enough_free_secs(sbi, 0, 0)) > >>>> - return; > >>>> + return submitted; > >>>> > >>>> if (check_valid_map(sbi, segno, off) == 0) > >>>> continue; > >>>> @@ -522,7 +524,9 @@ static void gc_node_segment(struct f2fs_sb_info *sbi, > >>>> continue; > >>>> } > >>>> > >>>> - f2fs_move_node_page(node_page, gc_type); > >>>> + err = f2fs_move_node_page(node_page, gc_type); > >>>> + if (!err && gc_type == FG_GC) > >>>> + submitted++; > >>>> stat_inc_node_blk_count(sbi, 1, gc_type); > >>>> } > >>>> > >>>> @@ -531,6 +535,7 @@ static void gc_node_segment(struct f2fs_sb_info *sbi, > >>>> > >>>> if (fggc) > >>>> atomic_dec(&sbi->wb_sync_req[NODE]); > >>>> + return submitted; > >>>> } > >>>> > >>>> /* > >>>> @@ -666,7 +671,7 @@ static int ra_data_block(struct inode *inode, pgoff_t index) > >>>> * Move data block via META_MAPPING while keeping locked data page. > >>>> * This can be used to move blocks, aka LBAs, directly on disk. > >>>> */ > >>>> -static void move_data_block(struct inode *inode, block_t bidx, > >>>> +static int move_data_block(struct inode *inode, block_t bidx, > >>>> int gc_type, unsigned int segno, int off) > >>> > >>> We don't need to submit IOs in this case. > >> > >> Actually, previously, we missed to submit IOs for encrypted block only in > >> BGGC, so we fix to submit for this case, all other codes are cleanups. Right? > > > > The move_data_block migrates encrypted blocks all the time with meta page IOs. > > I don't know what you're saying about BGGC. > > In move_data_block(), we use f2fs_submit_page_write() to add encrypted page > in to sbi->write_io[META].bio cache, so before exit GC, we need to submit > this cache by f2fs_submit_merged_write(), otherwise bio with encrypted page > will be cached in sbi->write_io[META].bio for long time, since we only > submmit this bio cache in foreground GC. > > if (gc_type == FG_GC) > f2fs_submit_merged_write(sbi, > (type == SUM_TYPE_NODE) ? NODE : DATA); Does this issue pending META IOs? I think META won't block any NODE/DATA pages. Moreover checkpoint or reading the moved block make the IOs be flushed, so it doesn't hurt the consistency. > > > > >> > >> Thanks, > >> > >>> > >>>> { > >>>> struct f2fs_io_info fio = { > >>>> @@ -685,25 +690,29 @@ static void move_data_block(struct inode *inode, block_t bidx, > >>>> struct node_info ni; > >>>> struct page *page, *mpage; > >>>> block_t newaddr; > >>>> - int err; > >>>> + int err = 0; > >>>> bool lfs_mode = test_opt(fio.sbi, LFS); > >>>> > >>>> /* do not read out */ > >>>> page = f2fs_grab_cache_page(inode->i_mapping, bidx, false); > >>>> if (!page) > >>>> - return; > >>>> + return -ENOMEM; > >>>> > >>>> - if (!check_valid_map(F2FS_I_SB(inode), segno, off)) > >>>> + if (!check_valid_map(F2FS_I_SB(inode), segno, off)) { > >>>> + err = -ENOENT; > >>>> goto out; > >>>> + } > >>>> > >>>> if (f2fs_is_atomic_file(inode)) { > >>>> F2FS_I(inode)->i_gc_failures[GC_FAILURE_ATOMIC]++; > >>>> F2FS_I_SB(inode)->skipped_atomic_files[gc_type]++; > >>>> + err = -EAGAIN; > >>>> goto out; > >>>> } > >>>> > >>>> if (f2fs_is_pinned_file(inode)) { > >>>> f2fs_pin_file_control(inode, true); > >>>> + err = -EAGAIN; > >>>> goto out; > >>>> } > >>>> > >>>> @@ -714,6 +723,7 @@ static void move_data_block(struct inode *inode, block_t bidx, > >>>> > >>>> if (unlikely(dn.data_blkaddr == NULL_ADDR)) { > >>>> ClearPageUptodate(page); > >>>> + err = -ENOENT; > >>>> goto put_out; > >>>> } > >>>> > >>>> @@ -796,6 +806,7 @@ static void move_data_block(struct inode *inode, block_t bidx, > >>>> fio.new_blkaddr = newaddr; > >>>> f2fs_submit_page_write(&fio); > >>>> if (fio.retry) { > >>>> + err = -EAGAIN; > >>>> if (PageWriteback(fio.encrypted_page)) > >>>> end_page_writeback(fio.encrypted_page); > >>>> goto put_page_out; > >>>> @@ -819,34 +830,42 @@ static void move_data_block(struct inode *inode, block_t bidx, > >>>> f2fs_put_dnode(&dn); > >>>> out: > >>>> f2fs_put_page(page, 1); > >>>> + return err; > >>>> } > >>>> > >>>> -static void move_data_page(struct inode *inode, block_t bidx, int gc_type, > >>>> +static int move_data_page(struct inode *inode, block_t bidx, int gc_type, > >>>> unsigned int segno, int off) > >>>> { > >>>> struct page *page; > >>>> + int err = 0; > >>>> > >>>> page = f2fs_get_lock_data_page(inode, bidx, true); > >>>> if (IS_ERR(page)) > >>>> - return; > >>>> + return PTR_ERR(page); > >>>> > >>>> - if (!check_valid_map(F2FS_I_SB(inode), segno, off)) > >>>> + if (!check_valid_map(F2FS_I_SB(inode), segno, off)) { > >>>> + err = -ENOENT; > >>>> goto out; > >>>> + } > >>>> > >>>> if (f2fs_is_atomic_file(inode)) { > >>>> F2FS_I(inode)->i_gc_failures[GC_FAILURE_ATOMIC]++; > >>>> F2FS_I_SB(inode)->skipped_atomic_files[gc_type]++; > >>>> + err = -EAGAIN; > >>>> goto out; > >>>> } > >>>> if (f2fs_is_pinned_file(inode)) { > >>>> if (gc_type == FG_GC) > >>>> f2fs_pin_file_control(inode, true); > >>>> + err = -EAGAIN; > >>>> goto out; > >>>> } > >>>> > >>>> if (gc_type == BG_GC) { > >>>> - if (PageWriteback(page)) > >>>> + if (PageWriteback(page)) { > >>>> + err = -EAGAIN; > >>>> goto out; > >>>> + } > >>>> set_page_dirty(page); > >>>> set_cold_data(page); > >>>> } else { > >>>> @@ -864,7 +883,6 @@ static void move_data_page(struct inode *inode, block_t bidx, int gc_type, > >>>> .io_type = FS_GC_DATA_IO, > >>>> }; > >>>> bool is_dirty = PageDirty(page); > >>>> - int err; > >>>> > >>>> retry: > >>>> set_page_dirty(page); > >>>> @@ -889,6 +907,7 @@ static void move_data_page(struct inode *inode, block_t bidx, int gc_type, > >>>> } > >>>> out: > >>>> f2fs_put_page(page, 1); > >>>> + return err; > >>>> } > >>>> > >>>> /* > >>>> @@ -898,7 +917,7 @@ static void move_data_page(struct inode *inode, block_t bidx, int gc_type, > >>>> * If the parent node is not valid or the data block address is different, > >>>> * the victim data block is ignored. > >>>> */ > >>>> -static void gc_data_segment(struct f2fs_sb_info *sbi, struct f2fs_summary *sum, > >>>> +static int gc_data_segment(struct f2fs_sb_info *sbi, struct f2fs_summary *sum, > >>>> struct gc_inode_list *gc_list, unsigned int segno, int gc_type) > >>>> { > >>>> struct super_block *sb = sbi->sb; > >>>> @@ -906,6 +925,7 @@ static void gc_data_segment(struct f2fs_sb_info *sbi, struct f2fs_summary *sum, > >>>> block_t start_addr; > >>>> int off; > >>>> int phase = 0; > >>>> + int submitted = 0; > >>>> > >>>> start_addr = START_BLOCK(sbi, segno); > >>>> > >>>> @@ -922,7 +942,7 @@ static void gc_data_segment(struct f2fs_sb_info *sbi, struct f2fs_summary *sum, > >>>> > >>>> /* stop BG_GC if there is not enough free sections. */ > >>>> if (gc_type == BG_GC && has_not_enough_free_secs(sbi, 0, 0)) > >>>> - return; > >>>> + return submitted; > >>>> > >>>> if (check_valid_map(sbi, segno, off) == 0) > >>>> continue; > >>>> @@ -994,6 +1014,7 @@ static void gc_data_segment(struct f2fs_sb_info *sbi, struct f2fs_summary *sum, > >>>> if (inode) { > >>>> struct f2fs_inode_info *fi = F2FS_I(inode); > >>>> bool locked = false; > >>>> + int err; > >>>> > >>>> if (S_ISREG(inode->i_mode)) { > >>>> if (!down_write_trylock(&fi->i_gc_rwsem[READ])) > >>>> @@ -1013,12 +1034,16 @@ static void gc_data_segment(struct f2fs_sb_info *sbi, struct f2fs_summary *sum, > >>>> start_bidx = f2fs_start_bidx_of_node(nofs, inode) > >>>> + ofs_in_node; > >>>> if (f2fs_post_read_required(inode)) > >>>> - move_data_block(inode, start_bidx, gc_type, > >>>> - segno, off); > >>>> + err = move_data_block(inode, start_bidx, > >>>> + gc_type, segno, off); > >>>> else > >>>> - move_data_page(inode, start_bidx, gc_type, > >>>> + err = move_data_page(inode, start_bidx, gc_type, > >>>> segno, off); > >>>> > >>>> + if (!err && (gc_type == FG_GC || > >>>> + f2fs_post_read_required(inode))) > >>>> + submitted++; > >>>> + > >>>> if (locked) { > >>>> up_write(&fi->i_gc_rwsem[WRITE]); > >>>> up_write(&fi->i_gc_rwsem[READ]); > >>>> @@ -1030,6 +1055,8 @@ static void gc_data_segment(struct f2fs_sb_info *sbi, struct f2fs_summary *sum, > >>>> > >>>> if (++phase < 5) > >>>> goto next_step; > >>>> + > >>>> + return submitted; > >>>> } > >>>> > >>>> static int __get_victim(struct f2fs_sb_info *sbi, unsigned int *victim, > >>>> @@ -1057,6 +1084,7 @@ static int do_garbage_collect(struct f2fs_sb_info *sbi, > >>>> int seg_freed = 0; > >>>> unsigned char type = IS_DATASEG(get_seg_entry(sbi, segno)->type) ? > >>>> SUM_TYPE_DATA : SUM_TYPE_NODE; > >>>> + int submitted = 0; > >>>> > >>>> /* readahead multi ssa blocks those have contiguous address */ > >>>> if (sbi->segs_per_sec > 1) > >>>> @@ -1100,10 +1128,11 @@ static int do_garbage_collect(struct f2fs_sb_info *sbi, > >>>> * - lock_page(sum_page) > >>>> */ > >>>> if (type == SUM_TYPE_NODE) > >>>> - gc_node_segment(sbi, sum->entries, segno, gc_type); > >>>> - else > >>>> - gc_data_segment(sbi, sum->entries, gc_list, segno, > >>>> + submitted += gc_node_segment(sbi, sum->entries, segno, > >>>> gc_type); > >>>> + else > >>>> + submitted += gc_data_segment(sbi, sum->entries, gc_list, > >>>> + segno, gc_type); > >>>> > >>>> stat_inc_seg_count(sbi, type, gc_type); > >>>> > >>>> @@ -1114,7 +1143,7 @@ static int do_garbage_collect(struct f2fs_sb_info *sbi, > >>>> f2fs_put_page(sum_page, 0); > >>>> } > >>>> > >>>> - if (gc_type == FG_GC) > >>>> + if (submitted) > >>>> f2fs_submit_merged_write(sbi, > >>>> (type == SUM_TYPE_NODE) ? NODE : DATA); > >>>> > >>>> diff --git a/fs/f2fs/node.c b/fs/f2fs/node.c > >>>> index fa2381c0bc47..214dd6326b4b 100644 > >>>> --- a/fs/f2fs/node.c > >>>> +++ b/fs/f2fs/node.c > >>>> @@ -1584,8 +1584,10 @@ static int __write_node_page(struct page *page, bool atomic, bool *submitted, > >>>> return AOP_WRITEPAGE_ACTIVATE; > >>>> } > >>>> > >>>> -void f2fs_move_node_page(struct page *node_page, int gc_type) > >>>> +int f2fs_move_node_page(struct page *node_page, int gc_type) > >>>> { > >>>> + int err = 0; > >>>> + > >>>> if (gc_type == FG_GC) { > >>>> struct writeback_control wbc = { > >>>> .sync_mode = WB_SYNC_ALL, > >>>> @@ -1597,12 +1599,16 @@ void f2fs_move_node_page(struct page *node_page, int gc_type) > >>>> f2fs_wait_on_page_writeback(node_page, NODE, true); > >>>> > >>>> f2fs_bug_on(F2FS_P_SB(node_page), PageWriteback(node_page)); > >>>> - if (!clear_page_dirty_for_io(node_page)) > >>>> + if (!clear_page_dirty_for_io(node_page)) { > >>>> + err = -EAGAIN; > >>>> goto out_page; > >>>> + } > >>>> > >>>> if (__write_node_page(node_page, false, NULL, > >>>> - &wbc, false, FS_GC_NODE_IO, NULL)) > >>>> + &wbc, false, FS_GC_NODE_IO, NULL)) { > >>>> + err = -EAGAIN; > >>>> unlock_page(node_page); > >>>> + } > >>>> goto release_page; > >>>> } else { > >>>> /* set page dirty and write it */ > >>>> @@ -1613,6 +1619,7 @@ void f2fs_move_node_page(struct page *node_page, int gc_type) > >>>> unlock_page(node_page); > >>>> release_page: > >>>> f2fs_put_page(node_page, 0); > >>>> + return err; > >>>> } > >>>> > >>>> static int f2fs_write_node_page(struct page *page, > >>>> -- > >>>> 2.18.0 > >>> > >>> . > >>> > > > > . > >