From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751982AbdB0Vxm (ORCPT ); Mon, 27 Feb 2017 16:53:42 -0500 Received: from mail.kernel.org ([198.145.29.136]:52358 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751810AbdB0VwE (ORCPT ); Mon, 27 Feb 2017 16:52:04 -0500 From: Jaegeuk Kim To: linux-kernel@vger.kernel.org, linux-fsdevel@vger.kernel.org, linux-f2fs-devel@lists.sourceforge.net Cc: Jaegeuk Kim , stable@vger.kernel.org, Damien Le Moal Subject: [PATCH] f2fs: avoid to issue redundant discard commands Date: Mon, 27 Feb 2017 13:43:55 -0800 Message-Id: <20170227214355.8405-1-jaegeuk@kernel.org> X-Mailer: git-send-email 2.11.0 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org If segs_per_sec is over 1 like under SMR, previously f2fs issues discard commands redundantly on the same section, since we didn't move end position for the previous discard command. E.g., start end | | prefree_bitmap = [01111100111100] And, after issue discard for this section, end start | | prefree_bitmap = [01111100111100] Select this section again by searching from (end + 1), start end | | prefree_bitmap = [01111100111100] Fixes: 36abef4e796d38 ("f2fs: introduce mode=lfs mount option") Cc: Cc: Damien Le Moal Signed-off-by: Jaegeuk Kim --- fs/f2fs/segment.c | 2 ++ 1 file changed, 2 insertions(+) diff --git a/fs/f2fs/segment.c b/fs/f2fs/segment.c index 9006d8ed6f52..4bd7a8b19332 100644 --- a/fs/f2fs/segment.c +++ b/fs/f2fs/segment.c @@ -1036,6 +1036,8 @@ void clear_prefree_segments(struct f2fs_sb_info *sbi, struct cp_control *cpc) start = start_segno + sbi->segs_per_sec; if (start < end) goto next; + else + end = start - 1; } mutex_unlock(&dirty_i->seglist_lock); -- 2.11.0