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=-18.0 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,NICE_REPLY_A,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED, 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 7F898C433E0 for ; Tue, 2 Feb 2021 12:11:40 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 37BA964DDE for ; Tue, 2 Feb 2021 12:11:40 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231375AbhBBMLP (ORCPT ); Tue, 2 Feb 2021 07:11:15 -0500 Received: from mail.kernel.org ([198.145.29.99]:43970 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231281AbhBBMKq (ORCPT ); Tue, 2 Feb 2021 07:10:46 -0500 Received: by mail.kernel.org (Postfix) with ESMTPSA id 8746B64F5D; Tue, 2 Feb 2021 12:09:57 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1612267804; bh=9+NYi16sShih4NLwkXwFR5WL/nfdEw9USH/MLzlKLf0=; h=Subject:To:Cc:References:From:Date:In-Reply-To:From; b=cnCXmnLPICDPpfKwbfP/LBk5ogUDs17Blml0u/mNc6+BAZjELgSZ/vc+M2LJSzPxC Egbx1BANNIaL8tao/EqSIQr6RMx6AdGG/6BXWkBYKAV84TV8Tz0wa5pQadGf89CRKr dMUWVA7m0Nraur8yoM/i5vmDFRDN2osl/gbTFDg7cNKGvfo1zvIDCpbIb3WFAcziCt ZrSPQVL0ZaqvksAYYkiKuvR4ij0vjGyQ6rTtjb/LTalVo2LzC6utYCOme/+KcZKMTK Zxd4zcQt9SaB6a4GL4qqIB2Ps2ix/0yK9alNHrAMRrzsOfk9WFhuZiQrErBNHhMi+I xIlL8Pr8aDF5Q== Subject: Re: [f2fs-dev] [PATCH v3] f2fs: rename checkpoint=merge mount option to checkpoint_merge To: Daeho Jeong , Chao Yu Cc: Daeho Jeong , kernel-team@android.com, linux-kernel@vger.kernel.org, linux-f2fs-devel@lists.sourceforge.net References: <20210202092332.2562006-1-daeho43@gmail.com> <938ce080-d211-0834-64b4-fd4836a26d5a@huawei.com> From: Chao Yu Message-ID: Date: Tue, 2 Feb 2021 20:09:49 +0800 User-Agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:78.0) Gecko/20100101 Thunderbird/78.6.0 MIME-Version: 1.0 In-Reply-To: Content-Type: text/plain; charset=utf-8; format=flowed Content-Language: en-US Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 2021/2/2 19:29, Daeho Jeong wrote: > Thanks for the explanation. > > I am going to remove the line clearing "MERGE_CHECKPOINT". > But, when we go with the below remount command, I think the > "nocheckpoint_merge" option will work well to disable only just > "checkpoint_merge" from the previous option. > "mount -o remount,nocheckpoint_merge /dir" > > It would be more convenient to users. What do you think? It's fine to me, please go ahead. :) Thanks, > > 2021년 2월 2일 (화) 오후 6:55, Chao Yu 님이 작성: >> >> On 2021/2/2 17:44, Daeho Jeong wrote: >>> When we remount it without the "checkpoint_merge" option, shouldn't we >>> need to clear "MERGE_CHECKPOINT" again? >>> This is actually what I intended, but I was wrong. Actually, I found this. >>> >>> When we remount the filesystem, the previous mount option is passed >>> through the "data" argument in the below. >>> f2fs_remount(struct super_block *sb, int *flags, char *data) >>> >>> If we don't provide the "nocheckpoint_merge" option, how can we turn >>> off the "checkpoint_merge" option which is turned on in the previous >>> mount? >> >> We can use "mount -o remount /dev/xxx /mnt" to disable checkpoint_merge, >> since that command won't pass old mount options to remount? >> >> Quoted from man mount: >> >> mount -o remount,rw /dev/foo /dir >> >> After this call all old mount options are replaced and arbitrary stuff from fstab (or mtab) is ignored, except the loop= option which is internally generated and maintained by the >> mount command. >> >> mount -o remount,rw /dir >> >> After this call mount reads fstab and merges these options with the options from the command line (-o). If no mountpoint found in fstab than remount with unspecified source is allowed. >> >> Thanks, >> >>> >>> 2021년 2월 2일 (화) 오후 6:28, Chao Yu 님이 작성: >>>> >>>> On 2021/2/2 17:23, Daeho Jeong wrote: >>>>> From: Daeho Jeong >>>>> >>>>> As checkpoint=merge comes in, mount option setting related to checkpoint >>>>> had been mixed up and it became hard to understand. So, I separated >>>>> this option from "checkpoint=" and made another mount option >>>>> "checkpoint_merge" for this. >>>>> >>>>> Signed-off-by: Daeho Jeong >>>>> --- >>>>> v2: renamed "checkpoint=merge" to "checkpoint_merge" >>>>> v3: removed "nocheckpoint_merge" option >>>>> --- >>>>> Documentation/filesystems/f2fs.rst | 6 +++--- >>>>> fs/f2fs/super.c | 21 +++++++++------------ >>>>> 2 files changed, 12 insertions(+), 15 deletions(-) >>>>> >>>>> diff --git a/Documentation/filesystems/f2fs.rst b/Documentation/filesystems/f2fs.rst >>>>> index d0ead45dc706..475994ed8b15 100644 >>>>> --- a/Documentation/filesystems/f2fs.rst >>>>> +++ b/Documentation/filesystems/f2fs.rst >>>>> @@ -247,9 +247,9 @@ checkpoint=%s[:%u[%]] Set to "disable" to turn off checkpointing. Set to "enabl >>>>> hide up to all remaining free space. The actual space that >>>>> would be unusable can be viewed at /sys/fs/f2fs//unusable >>>>> This space is reclaimed once checkpoint=enable. >>>>> - Here is another option "merge", which creates a kernel daemon >>>>> - and makes it to merge concurrent checkpoint requests as much >>>>> - as possible to eliminate redundant checkpoint issues. Plus, >>>>> +checkpoint_merge When checkpoint is enabled, this can be used to create a kernel >>>>> + daemon and make it to merge concurrent checkpoint requests as >>>>> + much as possible to eliminate redundant checkpoint issues. Plus, >>>>> we can eliminate the sluggish issue caused by slow checkpoint >>>>> operation when the checkpoint is done in a process context in >>>>> a cgroup having low i/o budget and cpu shares. To make this >>>>> diff --git a/fs/f2fs/super.c b/fs/f2fs/super.c >>>>> index 56696f6cfa86..b60dcef7f9d0 100644 >>>>> --- a/fs/f2fs/super.c >>>>> +++ b/fs/f2fs/super.c >>>>> @@ -215,7 +215,7 @@ static match_table_t f2fs_tokens = { >>>>> {Opt_checkpoint_disable_cap, "checkpoint=disable:%u"}, >>>>> {Opt_checkpoint_disable_cap_perc, "checkpoint=disable:%u%%"}, >>>>> {Opt_checkpoint_enable, "checkpoint=enable"}, >>>>> - {Opt_checkpoint_merge, "checkpoint=merge"}, >>>>> + {Opt_checkpoint_merge, "checkpoint_merge"}, >>>>> {Opt_compress_algorithm, "compress_algorithm=%s"}, >>>>> {Opt_compress_log_size, "compress_log_size=%u"}, >>>>> {Opt_compress_extension, "compress_extension=%s"}, >>>>> @@ -1142,12 +1142,6 @@ static int parse_options(struct super_block *sb, char *options, bool is_remount) >>>>> return -EINVAL; >>>>> } >>>>> >>>>> - if (test_opt(sbi, DISABLE_CHECKPOINT) && >>>>> - test_opt(sbi, MERGE_CHECKPOINT)) { >>>>> - f2fs_err(sbi, "checkpoint=merge cannot be used with checkpoint=disable\n"); >>>>> - return -EINVAL; >>>>> - } >>>>> - >>>>> /* Not pass down write hints if the number of active logs is lesser >>>>> * than NR_CURSEG_PERSIST_TYPE. >>>>> */ >>>>> @@ -1782,7 +1776,7 @@ static int f2fs_show_options(struct seq_file *seq, struct dentry *root) >>>>> seq_printf(seq, ",checkpoint=disable:%u", >>>>> F2FS_OPTION(sbi).unusable_cap); >>>>> if (test_opt(sbi, MERGE_CHECKPOINT)) >>>>> - seq_puts(seq, ",checkpoint=merge"); >>>>> + seq_puts(seq, ",checkpoint_merge"); >>>>> if (F2FS_OPTION(sbi).fsync_mode == FSYNC_MODE_POSIX) >>>>> seq_printf(seq, ",fsync_mode=%s", "posix"); >>>>> else if (F2FS_OPTION(sbi).fsync_mode == FSYNC_MODE_STRICT) >>>>> @@ -1827,6 +1821,7 @@ static void default_options(struct f2fs_sb_info *sbi) >>>>> sbi->sb->s_flags |= SB_LAZYTIME; >>>>> set_opt(sbi, FLUSH_MERGE); >>>>> set_opt(sbi, DISCARD); >>>>> + clear_opt(sbi, MERGE_CHECKPOINT); >>>> >>>> It's not needed here? >>>> >>>> Thanks, >>>> >>>>> if (f2fs_sb_has_blkzoned(sbi)) >>>>> F2FS_OPTION(sbi).fs_mode = FS_MODE_LFS; >>>>> else >>>>> @@ -2066,9 +2061,8 @@ static int f2fs_remount(struct super_block *sb, int *flags, char *data) >>>>> } >>>>> } >>>>> >>>>> - if (!test_opt(sbi, MERGE_CHECKPOINT)) { >>>>> - f2fs_stop_ckpt_thread(sbi); >>>>> - } else { >>>>> + if (!test_opt(sbi, DISABLE_CHECKPOINT) && >>>>> + test_opt(sbi, MERGE_CHECKPOINT)) { >>>>> err = f2fs_start_ckpt_thread(sbi); >>>>> if (err) { >>>>> f2fs_err(sbi, >>>>> @@ -2076,6 +2070,8 @@ static int f2fs_remount(struct super_block *sb, int *flags, char *data) >>>>> err); >>>>> goto restore_gc; >>>>> } >>>>> + } else { >>>>> + f2fs_stop_ckpt_thread(sbi); >>>>> } >>>>> >>>>> /* >>>>> @@ -3831,7 +3827,8 @@ static int f2fs_fill_super(struct super_block *sb, void *data, int silent) >>>>> >>>>> /* setup checkpoint request control and start checkpoint issue thread */ >>>>> f2fs_init_ckpt_req_control(sbi); >>>>> - if (test_opt(sbi, MERGE_CHECKPOINT)) { >>>>> + if (!test_opt(sbi, DISABLE_CHECKPOINT) && >>>>> + test_opt(sbi, MERGE_CHECKPOINT)) { >>>>> err = f2fs_start_ckpt_thread(sbi); >>>>> if (err) { >>>>> f2fs_err(sbi, >>>>> >>> . >>> > > > _______________________________________________ > Linux-f2fs-devel mailing list > Linux-f2fs-devel@lists.sourceforge.net > https://lists.sourceforge.net/lists/listinfo/linux-f2fs-devel >