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=-0.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_PASS,URIBL_BLOCKED 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 6C458ECDFB0 for ; Fri, 13 Jul 2018 03:14:24 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 1B8E02124D for ; Fri, 13 Jul 2018 03:14:24 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 1B8E02124D Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=huawei.com 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 S2387882AbeGMD0v (ORCPT ); Thu, 12 Jul 2018 23:26:51 -0400 Received: from szxga04-in.huawei.com ([45.249.212.190]:9616 "EHLO huawei.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S2387700AbeGMD0u (ORCPT ); Thu, 12 Jul 2018 23:26:50 -0400 Received: from DGGEMS405-HUB.china.huawei.com (unknown [172.30.72.59]) by Forcepoint Email with ESMTP id 64F743E365D89; Fri, 13 Jul 2018 11:14:03 +0800 (CST) Received: from [127.0.0.1] (10.134.22.195) by DGGEMS405-HUB.china.huawei.com (10.3.19.205) with Microsoft SMTP Server id 14.3.382.0; Fri, 13 Jul 2018 11:13:55 +0800 Subject: Re: [PATCH 2/5] f2fs: clear the remaining prefree_map of the section To: Yunlong Song , , , CC: , , , , , References: <1531408170-45758-1-git-send-email-yunlong.song@huawei.com> <1531408170-45758-3-git-send-email-yunlong.song@huawei.com> From: Chao Yu Message-ID: Date: Fri, 13 Jul 2018 11:13:54 +0800 User-Agent: Mozilla/5.0 (Windows NT 6.1; WOW64; rv:52.0) Gecko/20100101 Thunderbird/52.8.0 MIME-Version: 1.0 In-Reply-To: <1531408170-45758-3-git-send-email-yunlong.song@huawei.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 2018/7/12 23:09, Yunlong Song wrote: > For the case when sbi->segs_per_sec > 1, take section:segment = 5 for > example, if the section prefree_map is ...previous section | current > section (1 1 0 1 1) | next section..., then the start = x, end = x + 1, > after start = start_segno + sbi->segs_per_sec, start = x + 5, then it > will skip x + 3 and x + 4, but their bitmap is still set, which will > cause duplicated f2fs_issue_discard of this same section in the next > write_checkpoint, so fix it. I didn't get it, if # 2 segment is not prefree state, so it still has valid blocks there, so we won't issue discard due to below condition, right? if (!IS_CURSEC(sbi, secno) && !get_valid_blocks(sbi, start, true)) Thanks, > > Signed-off-by: Yunlong Song > --- > fs/f2fs/segment.c | 19 +++++++++++++++++-- > 1 file changed, 17 insertions(+), 2 deletions(-) > > diff --git a/fs/f2fs/segment.c b/fs/f2fs/segment.c > index 47b6595..fd38b61 100644 > --- a/fs/f2fs/segment.c > +++ b/fs/f2fs/segment.c > @@ -1684,8 +1684,23 @@ void f2fs_clear_prefree_segments(struct f2fs_sb_info *sbi, > start = start_segno + sbi->segs_per_sec; > if (start < end) > goto next; > - else > - end = start - 1; > + else { > + start_segno = start; > + > + while (1) { > + start = find_next_bit(prefree_map, start_segno, > + end + 1); > + if (start >= start_segno) > + break; > + end = find_next_zero_bit(prefree_map, start_segno, > + start + 1); > + for (i = start; i < end; i++) > + clear_bit(i, prefree_map); > + dirty_i->nr_dirty[PRE] -= end - start; > + } > + > + end = start_segno - 1; > + } > } > mutex_unlock(&dirty_i->seglist_lock); > >