From mboxrd@z Thu Jan 1 00:00:00 1970 From: Yunlei He Subject: [PATCH v2] f2fs: get victim segment again after new cp Date: Fri, 22 Jul 2016 19:08:31 +0800 Message-ID: <1469185711-27932-1-git-send-email-heyunlei@huawei.com> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: Received: from sog-mx-3.v43.ch3.sourceforge.com ([172.29.43.193] helo=mx.sourceforge.net) by sfs-ml-4.v29.ch3.sourceforge.com with esmtp (Exim 4.76) (envelope-from ) id 1bQYHX-0001ww-2p for linux-f2fs-devel@lists.sourceforge.net; Fri, 22 Jul 2016 11:06:15 +0000 Received: from szxga03-in.huawei.com ([119.145.14.66]) by sog-mx-3.v43.ch3.sourceforge.com with esmtps (TLSv1:RC4-SHA:128) (Exim 4.76) id 1bQYHS-0006hi-3J for linux-f2fs-devel@lists.sourceforge.net; Fri, 22 Jul 2016 11:06:15 +0000 List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: linux-f2fs-devel-bounces@lists.sourceforge.net To: linux-f2fs-devel@lists.sourceforge.net, jaegeuk@kernel.org, yuchao@huawei.com Cc: heyunlei@huwei.com Previous selected segment may become free after write_checkpoint, if we do garbage collect on this segment, and then new_curseg happen to reuse it, it may cause f2fs_bug_on as below. panic+0x154/0x29c do_garbage_collect+0x15c/0xaf4 f2fs_gc+0x2dc/0x444 f2fs_balance_fs.part.22+0xcc/0x14c f2fs_balance_fs+0x28/0x34 f2fs_map_blocks+0x5ec/0x790 f2fs_preallocate_blocks+0xe0/0x100 f2fs_file_write_iter+0x64/0x11c new_sync_write+0xac/0x11c vfs_write+0x144/0x1e4 SyS_write+0x60/0xc0 Here, maybe we check sit and ssa type during reset_curseg. So, we check segment is stale or not, and select a new victim to avoid this. Signed-off-by: Yunlei He --- fs/f2fs/gc.c | 8 ++++++-- 1 file changed, 6 insertions(+), 2 deletions(-) diff --git a/fs/f2fs/gc.c b/fs/f2fs/gc.c index de6c41c..ec17096 100644 --- a/fs/f2fs/gc.c +++ b/fs/f2fs/gc.c @@ -908,10 +908,14 @@ gc_more: * enough free sections, we should flush dent/node blocks and do * garbage collections. */ - if (__get_victim(sbi, &segno, gc_type) || prefree_segments(sbi)) + if (__get_victim(sbi, &segno, gc_type) || prefree_segments(sbi)) { write_checkpoint(sbi, &cpc); - else if (has_not_enough_free_secs(sbi, 0)) + if(!get_valid_blocks(sbi, segno, sbi->segs_per_sec) + || IS_CURSEC(sbi, segno / sbi->segs_per_sec)) + segno = NULL_SEGNO; + } else if (has_not_enough_free_secs(sbi, 0)) { write_checkpoint(sbi, &cpc); + } } if (segno == NULL_SEGNO && !__get_victim(sbi, &segno, gc_type)) -- 1.9.1 ------------------------------------------------------------------------------ What NetFlow Analyzer can do for you? Monitors network bandwidth and traffic patterns at an interface-level. Reveals which users, apps, and protocols are consuming the most bandwidth. Provides multi-vendor support for NetFlow, J-Flow, sFlow and other flows. Make informed decisions using capacity planning reports.http://sdm.link/zohodev2dev