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=-8.5 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS, USER_AGENT_SANE_1 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 810FBC00307 for ; Mon, 9 Sep 2019 08:06:16 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 4A8EA2086D for ; Mon, 9 Sep 2019 08:06:16 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1732085AbfIIIGP (ORCPT ); Mon, 9 Sep 2019 04:06:15 -0400 Received: from szxga04-in.huawei.com ([45.249.212.190]:2177 "EHLO huawei.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1726385AbfIIIGP (ORCPT ); Mon, 9 Sep 2019 04:06:15 -0400 Received: from DGGEMS409-HUB.china.huawei.com (unknown [172.30.72.58]) by Forcepoint Email with ESMTP id F30E6ACC6710D7563AB5; Mon, 9 Sep 2019 16:06:12 +0800 (CST) Received: from [10.134.22.195] (10.134.22.195) by smtp.huawei.com (10.3.19.209) with Microsoft SMTP Server (TLS) id 14.3.439.0; Mon, 9 Sep 2019 16:06:10 +0800 Subject: Re: [f2fs-dev] [PATCH 2/2] f2fs: avoid infinite GC loop due to stale atomic files To: Jaegeuk Kim CC: , References: <20190909012532.20454-1-jaegeuk@kernel.org> <20190909012532.20454-2-jaegeuk@kernel.org> <20190909073011.GA21625@jaegeuk-macbookpro.roam.corp.google.com> <5a473076-14b8-768a-62ac-f686e850d5a6@huawei.com> <20190909080108.GC21625@jaegeuk-macbookpro.roam.corp.google.com> From: Chao Yu Message-ID: Date: Mon, 9 Sep 2019 16:05:22 +0800 User-Agent: Mozilla/5.0 (Windows NT 6.1; WOW64; rv:52.0) Gecko/20100101 Thunderbird/52.9.1 MIME-Version: 1.0 In-Reply-To: <20190909080108.GC21625@jaegeuk-macbookpro.roam.corp.google.com> Content-Type: text/plain; charset="windows-1252" Content-Language: en-US Content-Transfer-Encoding: 7bit X-Originating-IP: [10.134.22.195] X-CFilter-Loop: Reflected Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 2019/9/9 16:01, Jaegeuk Kim wrote: > On 09/09, Chao Yu wrote: >> On 2019/9/9 15:30, Jaegeuk Kim wrote: >>> On 09/09, Chao Yu wrote: >>>> On 2019/9/9 9:25, Jaegeuk Kim wrote: >>>>> If committing atomic pages is failed when doing f2fs_do_sync_file(), we can >>>>> get commited pages but atomic_file being still set like: >>>>> >>>>> - inmem: 0, atomic IO: 4 (Max. 10), volatile IO: 0 (Max. 0) >>>>> >>>>> If GC selects this block, we can get an infinite loop like this: >>>>> >>>>> f2fs_submit_page_bio: dev = (253,7), ino = 2, page_index = 0x2359a8, oldaddr = 0x2359a8, newaddr = 0x2359a8, rw = READ(), type = COLD_DATA >>>>> f2fs_submit_read_bio: dev = (253,7)/(253,7), rw = READ(), DATA, sector = 18533696, size = 4096 >>>>> f2fs_get_victim: dev = (253,7), type = No TYPE, policy = (Foreground GC, LFS-mode, Greedy), victim = 4355, cost = 1, ofs_unit = 1, pre_victim_secno = 4355, prefree = 0, free = 234 >>>>> f2fs_iget: dev = (253,7), ino = 6247, pino = 5845, i_mode = 0x81b0, i_size = 319488, i_nlink = 1, i_blocks = 624, i_advise = 0x2c >>>>> f2fs_submit_page_bio: dev = (253,7), ino = 2, page_index = 0x2359a8, oldaddr = 0x2359a8, newaddr = 0x2359a8, rw = READ(), type = COLD_DATA >>>>> f2fs_submit_read_bio: dev = (253,7)/(253,7), rw = READ(), DATA, sector = 18533696, size = 4096 >>>>> f2fs_get_victim: dev = (253,7), type = No TYPE, policy = (Foreground GC, LFS-mode, Greedy), victim = 4355, cost = 1, ofs_unit = 1, pre_victim_secno = 4355, prefree = 0, free = 234 >>>>> f2fs_iget: dev = (253,7), ino = 6247, pino = 5845, i_mode = 0x81b0, i_size = 319488, i_nlink = 1, i_blocks = 624, i_advise = 0x2c >>>>> >>>>> In that moment, we can observe: >>>>> >>>>> [Before] >>>>> Try to move 5084219 blocks (BG: 384508) >>>>> - data blocks : 4962373 (274483) >>>>> - node blocks : 121846 (110025) >>>>> Skipped : atomic write 4534686 (10) >>>>> >>>>> [After] >>>>> Try to move 5088973 blocks (BG: 384508) >>>>> - data blocks : 4967127 (274483) >>>>> - node blocks : 121846 (110025) >>>>> Skipped : atomic write 4539440 (10) >>>>> >>>>> Signed-off-by: Jaegeuk Kim >>>>> --- >>>>> fs/f2fs/file.c | 10 +++++----- >>>>> 1 file changed, 5 insertions(+), 5 deletions(-) >>>>> >>>>> diff --git a/fs/f2fs/file.c b/fs/f2fs/file.c >>>>> index 7ae2f3bd8c2f..68b6da734e5f 100644 >>>>> --- a/fs/f2fs/file.c >>>>> +++ b/fs/f2fs/file.c >>>>> @@ -1997,11 +1997,11 @@ static int f2fs_ioc_commit_atomic_write(struct file *filp) >>>>> goto err_out; >>>>> >>>>> ret = f2fs_do_sync_file(filp, 0, LLONG_MAX, 0, true); >>>>> - if (!ret) { >>>>> - clear_inode_flag(inode, FI_ATOMIC_FILE); >>>>> - F2FS_I(inode)->i_gc_failures[GC_FAILURE_ATOMIC] = 0; >>>>> - stat_dec_atomic_write(inode); >>>>> - } >>>>> + >>>>> + /* doesn't need to check error */ >>>>> + clear_inode_flag(inode, FI_ATOMIC_FILE); >>>>> + F2FS_I(inode)->i_gc_failures[GC_FAILURE_ATOMIC] = 0; >>>>> + stat_dec_atomic_write(inode); >>>> >>>> If there are still valid atomic write pages linked in .inmem_pages, it may cause >>>> memory leak when we just clear FI_ATOMIC_FILE flag. >>> >>> f2fs_commit_inmem_pages() should have flushed them. >> >> Oh, we failed to flush its nodes. >> >> However we won't clear such info if we failed to flush inmen pages, it looks >> inconsistent. >> >> Any interface needed to drop inmem pages or clear ATOMIC_FILE flag in that two >> error path? I'm not very clear how sqlite handle such error. > > f2fs_drop_inmem_pages() did that, but not in this case. What I mean is, for any error returned from atomic_commit() interface, should userspace application handle it with consistent way, like trigger f2fs_drop_inmem_pages(), so we don't need to handle it inside atomic_commit(). > >> >> Thanks, >> >>> >>>> >>>> So my question is why below logic didn't handle such condition well? >>>> >>>> f2fs_gc() >>>> >>>> if (has_not_enough_free_secs(sbi, sec_freed, 0)) { >>>> if (skipped_round <= MAX_SKIP_GC_COUNT || >>>> skipped_round * 2 < round) { >>>> segno = NULL_SEGNO; >>>> goto gc_more; >>>> } >>>> >>>> if (first_skipped < last_skipped && >>>> (last_skipped - first_skipped) > >>>> sbi->skipped_gc_rwsem) { >>>> f2fs_drop_inmem_pages_all(sbi, true); >>> >>> This is doing nothing, since f2fs_commit_inmem_pages() removed the inode >>> from inmem list. >>> >>>> segno = NULL_SEGNO; >>>> goto gc_more; >>>> } >>>> if (gc_type == FG_GC && !is_sbi_flag_set(sbi, SBI_CP_DISABLED)) >>>> ret = f2fs_write_checkpoint(sbi, &cpc); >>>> } >>>> >>>>> } else { >>>>> ret = f2fs_do_sync_file(filp, 0, LLONG_MAX, 1, false); >>>>> } >>>>> >>> . >>> > . > 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=-8.3 required=3.0 tests=DKIM_INVALID,DKIM_SIGNED, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,USER_AGENT_SANE_1 autolearn=unavailable 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 C3E77C433EF for ; Mon, 9 Sep 2019 08:06:23 +0000 (UTC) Received: from lists.sourceforge.net (lists.sourceforge.net [216.105.38.7]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 8E7012086D; Mon, 9 Sep 2019 08:06:23 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (1024-bit key) header.d=sourceforge.net header.i=@sourceforge.net header.b="eGrLE+Si"; dkim=fail reason="signature verification failed" (1024-bit key) header.d=sf.net header.i=@sf.net header.b="lrD6PCFj" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 8E7012086D Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=huawei.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=linux-f2fs-devel-bounces@lists.sourceforge.net Received: from [127.0.0.1] (helo=sfs-ml-2.v29.lw.sourceforge.com) by sfs-ml-2.v29.lw.sourceforge.com with esmtp (Exim 4.90_1) (envelope-from ) id 1i7Egp-00008b-65; Mon, 09 Sep 2019 08:06:23 +0000 Received: from [172.30.20.202] (helo=mx.sourceforge.net) by sfs-ml-2.v29.lw.sourceforge.com with esmtps (TLSv1.2:ECDHE-RSA-AES256-GCM-SHA384:256) (Exim 4.90_1) (envelope-from ) id 1i7Egn-00008U-Vs for linux-f2fs-devel@lists.sourceforge.net; Mon, 09 Sep 2019 08:06:21 +0000 DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=sourceforge.net; s=x; h=Content-Transfer-Encoding:Content-Type:In-Reply-To: MIME-Version:Date:Message-ID:From:References:CC:To:Subject:Sender:Reply-To: 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=z2U0gRMOMqscX4yagDAP6n8suOvBJ7Qyc6+FpdoRhio=; b=eGrLE+Si1UPdIeWYJdGenYsnDn kCR1POw7aoiYpF7hUo/Bh5GER8doggFKxZ8fJNeUD0PitXfTOIcl5A2XLiXAfVPdXVbKkTK5t2RGx ifMnvYnIh4e/onhV60fUAGFinUnLJtEx7IOp31LVOzUb1EeIBovX0qOGDHRLBjz6C3Cw=; DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=sf.net; s=x ; h=Content-Transfer-Encoding:Content-Type:In-Reply-To:MIME-Version:Date: Message-ID:From:References:CC:To:Subject:Sender:Reply-To: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=z2U0gRMOMqscX4yagDAP6n8suOvBJ7Qyc6+FpdoRhio=; b=lrD6PCFjwi+X+uRqhqC6C/KX4z 2R9YgWjU4u6Lwspt3ogCjEpOLj7c0HFl0GnyJoawHWjoiC9TNBhB816DuTBzVWARYfrDkXFEn0zWl 8qhOnIMKNH2nNZeodHv5jv/NdHIZhVH6d7t9K0j0xSIlvL3WYH8s/iSyT3S6CrgaHLP4=; Received: from szxga04-in.huawei.com ([45.249.212.190] helo=huawei.com) by sfi-mx-3.v28.lw.sourceforge.com with esmtps (TLSv1.2:ECDHE-RSA-AES256-GCM-SHA384:256) (Exim 4.90_1) id 1i7Egl-00FK4t-Vu for linux-f2fs-devel@lists.sourceforge.net; Mon, 09 Sep 2019 08:06:21 +0000 Received: from DGGEMS409-HUB.china.huawei.com (unknown [172.30.72.58]) by Forcepoint Email with ESMTP id F30E6ACC6710D7563AB5; Mon, 9 Sep 2019 16:06:12 +0800 (CST) Received: from [10.134.22.195] (10.134.22.195) by smtp.huawei.com (10.3.19.209) with Microsoft SMTP Server (TLS) id 14.3.439.0; Mon, 9 Sep 2019 16:06:10 +0800 To: Jaegeuk Kim References: <20190909012532.20454-1-jaegeuk@kernel.org> <20190909012532.20454-2-jaegeuk@kernel.org> <20190909073011.GA21625@jaegeuk-macbookpro.roam.corp.google.com> <5a473076-14b8-768a-62ac-f686e850d5a6@huawei.com> <20190909080108.GC21625@jaegeuk-macbookpro.roam.corp.google.com> From: Chao Yu Message-ID: Date: Mon, 9 Sep 2019 16:05:22 +0800 User-Agent: Mozilla/5.0 (Windows NT 6.1; WOW64; rv:52.0) Gecko/20100101 Thunderbird/52.9.1 MIME-Version: 1.0 In-Reply-To: <20190909080108.GC21625@jaegeuk-macbookpro.roam.corp.google.com> Content-Language: en-US X-Originating-IP: [10.134.22.195] X-CFilter-Loop: Reflected X-Headers-End: 1i7Egl-00FK4t-Vu Subject: Re: [f2fs-dev] [PATCH 2/2] f2fs: avoid infinite GC loop due to stale atomic files X-BeenThere: linux-f2fs-devel@lists.sourceforge.net X-Mailman-Version: 2.1.21 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: linux-kernel@vger.kernel.org, linux-f2fs-devel@lists.sourceforge.net Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Errors-To: linux-f2fs-devel-bounces@lists.sourceforge.net On 2019/9/9 16:01, Jaegeuk Kim wrote: > On 09/09, Chao Yu wrote: >> On 2019/9/9 15:30, Jaegeuk Kim wrote: >>> On 09/09, Chao Yu wrote: >>>> On 2019/9/9 9:25, Jaegeuk Kim wrote: >>>>> If committing atomic pages is failed when doing f2fs_do_sync_file(), we can >>>>> get commited pages but atomic_file being still set like: >>>>> >>>>> - inmem: 0, atomic IO: 4 (Max. 10), volatile IO: 0 (Max. 0) >>>>> >>>>> If GC selects this block, we can get an infinite loop like this: >>>>> >>>>> f2fs_submit_page_bio: dev = (253,7), ino = 2, page_index = 0x2359a8, oldaddr = 0x2359a8, newaddr = 0x2359a8, rw = READ(), type = COLD_DATA >>>>> f2fs_submit_read_bio: dev = (253,7)/(253,7), rw = READ(), DATA, sector = 18533696, size = 4096 >>>>> f2fs_get_victim: dev = (253,7), type = No TYPE, policy = (Foreground GC, LFS-mode, Greedy), victim = 4355, cost = 1, ofs_unit = 1, pre_victim_secno = 4355, prefree = 0, free = 234 >>>>> f2fs_iget: dev = (253,7), ino = 6247, pino = 5845, i_mode = 0x81b0, i_size = 319488, i_nlink = 1, i_blocks = 624, i_advise = 0x2c >>>>> f2fs_submit_page_bio: dev = (253,7), ino = 2, page_index = 0x2359a8, oldaddr = 0x2359a8, newaddr = 0x2359a8, rw = READ(), type = COLD_DATA >>>>> f2fs_submit_read_bio: dev = (253,7)/(253,7), rw = READ(), DATA, sector = 18533696, size = 4096 >>>>> f2fs_get_victim: dev = (253,7), type = No TYPE, policy = (Foreground GC, LFS-mode, Greedy), victim = 4355, cost = 1, ofs_unit = 1, pre_victim_secno = 4355, prefree = 0, free = 234 >>>>> f2fs_iget: dev = (253,7), ino = 6247, pino = 5845, i_mode = 0x81b0, i_size = 319488, i_nlink = 1, i_blocks = 624, i_advise = 0x2c >>>>> >>>>> In that moment, we can observe: >>>>> >>>>> [Before] >>>>> Try to move 5084219 blocks (BG: 384508) >>>>> - data blocks : 4962373 (274483) >>>>> - node blocks : 121846 (110025) >>>>> Skipped : atomic write 4534686 (10) >>>>> >>>>> [After] >>>>> Try to move 5088973 blocks (BG: 384508) >>>>> - data blocks : 4967127 (274483) >>>>> - node blocks : 121846 (110025) >>>>> Skipped : atomic write 4539440 (10) >>>>> >>>>> Signed-off-by: Jaegeuk Kim >>>>> --- >>>>> fs/f2fs/file.c | 10 +++++----- >>>>> 1 file changed, 5 insertions(+), 5 deletions(-) >>>>> >>>>> diff --git a/fs/f2fs/file.c b/fs/f2fs/file.c >>>>> index 7ae2f3bd8c2f..68b6da734e5f 100644 >>>>> --- a/fs/f2fs/file.c >>>>> +++ b/fs/f2fs/file.c >>>>> @@ -1997,11 +1997,11 @@ static int f2fs_ioc_commit_atomic_write(struct file *filp) >>>>> goto err_out; >>>>> >>>>> ret = f2fs_do_sync_file(filp, 0, LLONG_MAX, 0, true); >>>>> - if (!ret) { >>>>> - clear_inode_flag(inode, FI_ATOMIC_FILE); >>>>> - F2FS_I(inode)->i_gc_failures[GC_FAILURE_ATOMIC] = 0; >>>>> - stat_dec_atomic_write(inode); >>>>> - } >>>>> + >>>>> + /* doesn't need to check error */ >>>>> + clear_inode_flag(inode, FI_ATOMIC_FILE); >>>>> + F2FS_I(inode)->i_gc_failures[GC_FAILURE_ATOMIC] = 0; >>>>> + stat_dec_atomic_write(inode); >>>> >>>> If there are still valid atomic write pages linked in .inmem_pages, it may cause >>>> memory leak when we just clear FI_ATOMIC_FILE flag. >>> >>> f2fs_commit_inmem_pages() should have flushed them. >> >> Oh, we failed to flush its nodes. >> >> However we won't clear such info if we failed to flush inmen pages, it looks >> inconsistent. >> >> Any interface needed to drop inmem pages or clear ATOMIC_FILE flag in that two >> error path? I'm not very clear how sqlite handle such error. > > f2fs_drop_inmem_pages() did that, but not in this case. What I mean is, for any error returned from atomic_commit() interface, should userspace application handle it with consistent way, like trigger f2fs_drop_inmem_pages(), so we don't need to handle it inside atomic_commit(). > >> >> Thanks, >> >>> >>>> >>>> So my question is why below logic didn't handle such condition well? >>>> >>>> f2fs_gc() >>>> >>>> if (has_not_enough_free_secs(sbi, sec_freed, 0)) { >>>> if (skipped_round <= MAX_SKIP_GC_COUNT || >>>> skipped_round * 2 < round) { >>>> segno = NULL_SEGNO; >>>> goto gc_more; >>>> } >>>> >>>> if (first_skipped < last_skipped && >>>> (last_skipped - first_skipped) > >>>> sbi->skipped_gc_rwsem) { >>>> f2fs_drop_inmem_pages_all(sbi, true); >>> >>> This is doing nothing, since f2fs_commit_inmem_pages() removed the inode >>> from inmem list. >>> >>>> segno = NULL_SEGNO; >>>> goto gc_more; >>>> } >>>> if (gc_type == FG_GC && !is_sbi_flag_set(sbi, SBI_CP_DISABLED)) >>>> ret = f2fs_write_checkpoint(sbi, &cpc); >>>> } >>>> >>>>> } else { >>>>> ret = f2fs_do_sync_file(filp, 0, LLONG_MAX, 1, false); >>>>> } >>>>> >>> . >>> > . > _______________________________________________ Linux-f2fs-devel mailing list Linux-f2fs-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/linux-f2fs-devel