Re: [PATCH] f2fs: support to show noage_extent_cache mount option

[Chao Yu]

On 2023/4/4 1:40, Jaegeuk Kim wrote:
> On 03/31, Yangtao Li wrote:
> > This patch support noage_extent_cache mount option.
> >
> > Signed-off-by: Yangtao Li <frank.li@xxxxxxxx>
> > ---
> >   Documentation/filesystems/f2fs.rst | 2 ++
> >   fs/f2fs/super.c                    | 7 +++++++
> >   2 files changed, 9 insertions(+)
> >
> > diff --git a/Documentation/filesystems/f2fs.rst b/Documentation/filesystems/f2fs.rst
> > index a81c896464ff..75505ab88de8 100644
> > --- a/Documentation/filesystems/f2fs.rst
> > +++ b/Documentation/filesystems/f2fs.rst
> > @@ -352,6 +352,8 @@ age_extent_cache	 Enable an age extent cache based on rb-tree. It records
> >   			 data block update frequency of the extent per inode, in
> >   			 order to provide better temperature hints for data block
> >   			 allocation.
> > +noage_extent_cache		 Disable an age extent cache based on rb-tree, see
> > +			 the above age_extent_cache mount option.
>
> Hmm, why do we need?

Hi Yangtao,

Please check the reason why we need to add no{inline_data, extent_cache, ...} mount
option as below:

commit 75342797988a0f9ebec400a2dde8d4de581c4079
Author: Wanpeng Li <wanpeng.li@xxxxxxxxxxxxxxx>
Date:   Tue Mar 24 10:20:27 2015 +0800

    f2fs: enable inline data by default

    Enable inline_data feature by default since it brings us better
    performance and space utilization and now has already stable.
    Add another option noinline_data to disable it during mount.

Thanks,

> >   ======================== ============================================================
> >   
> >   Debugfs Entries
> > diff --git a/fs/f2fs/super.c b/fs/f2fs/super.c
> > index b5828a67f7c1..8bd9953ea7e3 100644
> > --- a/fs/f2fs/super.c
> > +++ b/fs/f2fs/super.c
> > @@ -165,6 +165,7 @@ enum {
> >   	Opt_discard_unit,
> >   	Opt_memory_mode,
> >   	Opt_age_extent_cache,
> > +	Opt_noage_extent_cache,
> >   	Opt_err,
> >   };
> >   
> > @@ -244,6 +245,7 @@ static match_table_t f2fs_tokens = {
> >   	{Opt_discard_unit, "discard_unit=%s"},
> >   	{Opt_memory_mode, "memory=%s"},
> >   	{Opt_age_extent_cache, "age_extent_cache"},
> > +	{Opt_noage_extent_cache, "noage_extent_cache"},
> >   	{Opt_err, NULL},
> >   };
> >   
> > @@ -1269,6 +1271,9 @@ static int parse_options(struct super_block *sb, char *options, bool is_remount)
> >   		case Opt_age_extent_cache:
> >   			set_opt(sbi, AGE_EXTENT_CACHE);
> >   			break;
> > +		case Opt_noage_extent_cache:
> > +			clear_opt(sbi, AGE_EXTENT_CACHE);
> > +			break;
> >   		default:
> >   			f2fs_err(sbi, "Unrecognized mount option \"%s\" or missing value",
> >   				 p);
> > @@ -1974,6 +1979,8 @@ static int f2fs_show_options(struct seq_file *seq, struct dentry *root)
> >   		seq_puts(seq, ",noextent_cache");
> >   	if (test_opt(sbi, AGE_EXTENT_CACHE))
> >   		seq_puts(seq, ",age_extent_cache");
> > +	else
> > +		seq_puts(seq, ",noage_extent_cache");
> >   	if (test_opt(sbi, DATA_FLUSH))
> >   		seq_puts(seq, ",data_flush");
> >   
> > --
> > 2.35.1