From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756400AbdKGClB (ORCPT ); Mon, 6 Nov 2017 21:41:01 -0500 Received: from mail.kernel.org ([198.145.29.99]:34720 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1756381AbdKGCk7 (ORCPT ); Mon, 6 Nov 2017 21:40:59 -0500 DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 2FB8721870 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=kernel.org Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=jaegeuk@kernel.org Date: Mon, 6 Nov 2017 18:40:58 -0800 From: Jaegeuk Kim To: Yunlong Song Cc: chao@kernel.org, yuchao0@huawei.com, yunlong.song@icloud.com, miaoxie@huawei.com, bintian.wang@huawei.com, linux-fsdevel@vger.kernel.org, linux-f2fs-devel@lists.sourceforge.net, linux-kernel@vger.kernel.org Subject: Re: [PATCH v2] f2fs: add bug_on when f2fs_gc even fails to get one victim Message-ID: <20171107024058.GH88544@jaegeuk-macbookpro.roam.corp.google.com> References: <1507729864-118702-1-git-send-email-yunlong.song@huawei.com> <1507901500-162168-1-git-send-email-yunlong.song@huawei.com> <20171103034402.GC11335@jaegeuk-macbookpro.roam.corp.google.com> <3b26badb-c34e-3c2d-74a2-26ecef1f64ff@huawei.com> <20171107023835.GG88544@jaegeuk-macbookpro.roam.corp.google.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20171107023835.GG88544@jaegeuk-macbookpro.roam.corp.google.com> User-Agent: Mutt/1.8.2 (2017-04-18) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 11/06, Jaegeuk Kim wrote: > On 11/06, Yunlong Song wrote: > > Agree. > > > > On 2017/11/3 11:44, Jaegeuk Kim wrote: > > > On 10/13, Yunlong Song wrote: > > > > This can help us to debug on some corner case. > > > > > > > > Signed-off-by: Yunlong Song > > > > Signed-off-by: Chao Yu > > > > --- > > > > fs/f2fs/gc.c | 6 +++++- > > > > 1 file changed, 5 insertions(+), 1 deletion(-) > > > > > > > > diff --git a/fs/f2fs/gc.c b/fs/f2fs/gc.c > > > > index 197ebf4..2b03202 100644 > > > > --- a/fs/f2fs/gc.c > > > > +++ b/fs/f2fs/gc.c > > > > @@ -986,6 +986,7 @@ int f2fs_gc(struct f2fs_sb_info *sbi, bool sync, > > > > .ilist = LIST_HEAD_INIT(gc_list.ilist), > > > > .iroot = RADIX_TREE_INIT(GFP_NOFS), > > > > }; > > > > + bool need_fggc = false; > > > > trace_f2fs_gc_begin(sbi->sb, sync, background, > > > > get_pages(sbi, F2FS_DIRTY_NODES), > > > > @@ -1018,8 +1019,10 @@ int f2fs_gc(struct f2fs_sb_info *sbi, bool sync, > > > > if (ret) > > > > goto stop; > > > > } > > > > - if (has_not_enough_free_secs(sbi, 0, 0)) > > > > + if (has_not_enough_free_secs(sbi, 0, 0)) { > > > > gc_type = FG_GC; > > > > + need_fggc = true; > > > > + } > > > > } > > > > /* f2fs_balance_fs doesn't need to do BG_GC in critical path. */ > > > > @@ -1028,6 +1031,7 @@ int f2fs_gc(struct f2fs_sb_info *sbi, bool sync, > > > > goto stop; > > > > } > > > > if (!__get_victim(sbi, &segno, gc_type)) { > > > > + f2fs_bug_on(sbi, !total_freed && need_fggc); > > > Just like this? > > That's OK. > > I'm not quite sure whether this is really a bug_on case. > Let me make it WARN_ON() for debugging purpose first. BTW, why is this the special case where BG_GC detects FG_GC? > > Thanks, > > > > > > > > > f2fs_bug_on(sbi, !total_freed && !sync && gc_type == FG_GC); > > > > > > > ret = -ENODATA; > > > > goto stop; > > > > } > > > > -- > > > > 1.8.5.2 > > > . > > > > > > > -- > > Thanks, > > Yunlong Song > >