The rightmost one is the final option. And checkpoint=merge means
checkpoint is enabled with a checkpoint thread.
mount checkpoint=disable,checkpoint=merge => checkpoint=merge
remount checkpoint=enable,checkpoint=merge => checkpoint=merge
remount checkpoint=merge,checkpoint=disable => checkpoint=disable
remount checkpoint=merge,checkpoint=enable => checkpoint=enable
Like
mount fsync_mode=posix, fsync_mode=strict, fsync_mode=nobarrier =>
fsync_mode=nobarrier
2021년 2월 2일 (화) 오전 5:11, Jaegeuk Kim <jaeg...@kernel.org>님이 작성:
>
> On 02/01, Daeho Jeong wrote:
> > Actually, I think we need to select one among them, disable, enable
> > and merge. I realized my previous understanding about that was wrong.
> > In that case of "checkpoint=merge,checkpoint=enable", the last option
> > will override the ones before that.
> > This is how the other mount options like fsync_mode, whint_mode and etc.
> > So, the answer will be "checkpoint=enable". What do you think?
>
> We need to clarify a bit more. :)
>
> mount checkpoint=disable,checkpoint=merge
> remount checkpoint=enable,checkpoint=merge
>
> Then, is it going to enable checkpoint with a thread?
>
> >
> >
> >
> > 2021년 2월 1일 (월) 오후 9:40, Chao Yu <c...@kernel.org>님이 작성:
> > >
> > > On 2021/2/1 8:06, Daeho Jeong wrote:
> > > > From: Daeho Jeong <daehoje...@google.com>
> > > >
> > > > As checkpoint=merge comes in, mount option setting related to
> > > > checkpoint had been mixed up. Fixed it.
> > > >
> > > > Signed-off-by: Daeho Jeong <daehoje...@google.com>
> > > > ---
> > > > fs/f2fs/super.c | 11 +++++------
> > > > 1 file changed, 5 insertions(+), 6 deletions(-)
> > > >
> > > > diff --git a/fs/f2fs/super.c b/fs/f2fs/super.c
> > > > index 56696f6cfa86..8231c888c772 100644
> > > > --- a/fs/f2fs/super.c
> > > > +++ b/fs/f2fs/super.c
> > > > @@ -930,20 +930,25 @@ static int parse_options(struct super_block *sb,
> > > > char *options, bool is_remount)
> > > > return -EINVAL;
> > > > F2FS_OPTION(sbi).unusable_cap_perc = arg;
> > > > set_opt(sbi, DISABLE_CHECKPOINT);
> > > > + clear_opt(sbi, MERGE_CHECKPOINT);
> > > > break;
> > > > case Opt_checkpoint_disable_cap:
> > > > if (args->from && match_int(args, &arg))
> > > > return -EINVAL;
> > > > F2FS_OPTION(sbi).unusable_cap = arg;
> > > > set_opt(sbi, DISABLE_CHECKPOINT);
> > > > + clear_opt(sbi, MERGE_CHECKPOINT);
> > > > break;
> > > > case Opt_checkpoint_disable:
> > > > set_opt(sbi, DISABLE_CHECKPOINT);
> > > > + clear_opt(sbi, MERGE_CHECKPOINT);
> > > > break;
> > > > case Opt_checkpoint_enable:
> > > > clear_opt(sbi, DISABLE_CHECKPOINT);
> > > > + clear_opt(sbi, MERGE_CHECKPOINT);
> > >
> > > What if: -o checkpoint=merge,checkpoint=enable
> > >
> > > Can you please explain the rule of merge/disable/enable combination and
> > > their
> > > result? e.g.
> > > checkpoint=merge,checkpoint=enable
> > > checkpoint=enable,checkpoint=merge
> > > checkpoint=merge,checkpoint=disable
> > > checkpoint=disable,checkpoint=merge
> > >
> > > If the rule/result is clear, it should be documented.
> > >
> > > Thanks,
> > >
> > >
> > > > break;
> > > > case Opt_checkpoint_merge:
> > > > + clear_opt(sbi, DISABLE_CHECKPOINT);
> > > > set_opt(sbi, MERGE_CHECKPOINT);
> > > > break;
> > > > #ifdef CONFIG_F2FS_FS_COMPRESSION
> > > > @@ -1142,12 +1147,6 @@ 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.
> > > > */
> > > >
> >
> >
> > _______________________________________________
> > Linux-f2fs-devel mailing list
> > linux-f2fs-de...@lists.sourceforge.net
> > https://lists.sourceforge.net/lists/listinfo/linux-f2fs-devel
