Re: [PATCH v2 2/2] f2fs: use ioprio hint for hot and pinned files

[Chao Yu]

On 6/15/25 22:42, Daniel Lee wrote:
> Apply the `ioprio_hint` to set `F2FS_IOPRIO_WRITE` priority
> on files identified as "hot" at creation and on files that are
> pinned via ioctl.
> 
> Signed-off-by: Daniel Lee <chullee@xxxxxxxxxx>
> ---
>  fs/f2fs/f2fs.h  | 19 +++++++++++++++++++
>  fs/f2fs/file.c  |  3 +++
>  fs/f2fs/namei.c | 11 +++++++----
>  3 files changed, 29 insertions(+), 4 deletions(-)
> 
> diff --git a/fs/f2fs/f2fs.h b/fs/f2fs/f2fs.h
> index 3e02687c1b58..0c4f52892ff7 100644
> --- a/fs/f2fs/f2fs.h
> +++ b/fs/f2fs/f2fs.h
> @@ -3440,6 +3440,25 @@ static inline void set_file(struct inode *inode, int type)
>  	f2fs_mark_inode_dirty_sync(inode, true);
>  }
>  
> +static inline int get_ioprio(struct inode *inode)
> +{
> +	return F2FS_I(inode)->ioprio_hint;
> +}
> +
> +static inline void set_ioprio(struct inode *inode, int level)
> +{
> +	if (get_ioprio(inode) == level)
> +		return;
> +	F2FS_I(inode)->ioprio_hint = level;
> +}
> +
> +static inline void clear_ioprio(struct inode *inode)
> +{
> +	if (get_ioprio(inode) == 0)
> +		return;
> +	F2FS_I(inode)->ioprio_hint = 0;
> +}
> +
>  static inline void clear_file(struct inode *inode, int type)
>  {
>  	if (!is_file(inode, type))
> diff --git a/fs/f2fs/file.c b/fs/f2fs/file.c
> index 3eb40d7bf602..a18fb7f3d019 100644
> --- a/fs/f2fs/file.c
> +++ b/fs/f2fs/file.c
> @@ -3496,6 +3496,7 @@ static int f2fs_ioc_set_pin_file(struct file *filp, unsigned long arg)
>  
>  	if (!pin) {
>  		clear_inode_flag(inode, FI_PIN_FILE);
> +		clear_ioprio(inode);

I guess there are more places clearing FI_PIN_FILE? we need to cover
them all?

>  		f2fs_i_gc_failures_write(inode, 0);
>  		goto done;
>  	} else if (f2fs_is_pinned_file(inode)) {
> @@ -3529,6 +3530,8 @@ static int f2fs_ioc_set_pin_file(struct file *filp, unsigned long arg)
>  	}
>  
>  	set_inode_flag(inode, FI_PIN_FILE);
> +	file_set_hot(inode);

Unnecessary file_set_hot() invoking? Or am I missing anything?

Thanks,

> +	set_ioprio(inode, F2FS_IOPRIO_WRITE);
>  	ret = F2FS_I(inode)->i_gc_failures;
>  done:
>  	f2fs_update_time(sbi, REQ_TIME);
> diff --git a/fs/f2fs/namei.c b/fs/f2fs/namei.c
> index 07e333ee21b7..0f96a0b86c40 100644
> --- a/fs/f2fs/namei.c
> +++ b/fs/f2fs/namei.c
> @@ -191,9 +191,10 @@ static void set_compress_new_inode(struct f2fs_sb_info *sbi, struct inode *dir,
>  }
>  
>  /*
> - * Set file's temperature for hot/cold data separation
> + * Set file's temperature (for hot/cold data separation) and
> + * I/O priority, based on filename extension
>   */
> -static void set_file_temperature(struct f2fs_sb_info *sbi, struct inode *inode,
> +static void set_file_temp_prio(struct f2fs_sb_info *sbi, struct inode *inode,
>  		const unsigned char *name)
>  {
>  	__u8 (*extlist)[F2FS_EXTENSION_LEN] = sbi->raw_super->extension_list;
> @@ -212,8 +213,10 @@ static void set_file_temperature(struct f2fs_sb_info *sbi, struct inode *inode,
>  
>  	if (i < cold_count)
>  		file_set_cold(inode);
> -	else
> +	else {
>  		file_set_hot(inode);
> +		set_ioprio(inode, F2FS_IOPRIO_WRITE);
> +	}
>  }
>  
>  static struct inode *f2fs_new_inode(struct mnt_idmap *idmap,
> @@ -317,7 +320,7 @@ static struct inode *f2fs_new_inode(struct mnt_idmap *idmap,
>  		set_inode_flag(inode, FI_INLINE_DATA);
>  
>  	if (name && !test_opt(sbi, DISABLE_EXT_IDENTIFY))
> -		set_file_temperature(sbi, inode, name);
> +		set_file_temp_prio(sbi, inode, name);
>  
>  	stat_inc_inline_xattr(inode);
>  	stat_inc_inline_inode(inode);