[+Cc linux-block for FUA, and linux-xfs for iomap]
On Fri, May 27, 2022 at 01:59:55PM -0700, Jaegeuk Kim wrote:
> Some UFS storage gives slower performance on FUA than write+cache_flush.
> Let's give a way to manage it.
>
> Signed-off-by: Jaegeuk Kim <jaegeuk@xxxxxxxxxx>
Should the driver even be saying that it has FUA support in this case? If the
driver didn't claim FUA support, that would also solve this problem.
> ---
> Documentation/ABI/testing/sysfs-fs-f2fs | 7 +++++++
> fs/f2fs/data.c | 2 ++
> fs/f2fs/f2fs.h | 1 +
> fs/f2fs/sysfs.c | 2 ++
> 4 files changed, 12 insertions(+)
>
> diff --git a/Documentation/ABI/testing/sysfs-fs-f2fs b/Documentation/ABI/testing/sysfs-fs-f2fs
> index 9b583dd0298b..cd96b09d7182 100644
> --- a/Documentation/ABI/testing/sysfs-fs-f2fs
> +++ b/Documentation/ABI/testing/sysfs-fs-f2fs
> @@ -434,6 +434,7 @@ Date: April 2020
> Contact: "Daeho Jeong" <daehojeong@xxxxxxxxxx>
> Description: Give a way to change iostat_period time. 3secs by default.
> The new iostat trace gives stats gap given the period.
> +
> What: /sys/fs/f2fs/<disk>/max_io_bytes
> Date: December 2020
> Contact: "Jaegeuk Kim" <jaegeuk@xxxxxxxxxx>
> @@ -442,6 +443,12 @@ Description: This gives a control to limit the bio size in f2fs.
> whereas, if it has a certain bytes value, f2fs won't submit a
> bio larger than that size.
>
> +What: /sys/fs/f2fs/<disk>/no_fua_dio
> +Date: May 2022
> +Contact: "Jaegeuk Kim" <jaegeuk@xxxxxxxxxx>
> +Description: This gives a signal to iomap, which should not use FUA for
> + direct IOs. Default: 0.
iomap is an implementation detail, so it shouldn't be mentioned in UAPI
documentation. UAPI documentation should describe user-visible behavior only.
> +
> What: /sys/fs/f2fs/<disk>/stat/sb_status
> Date: December 2020
> Contact: "Chao Yu" <yuchao0@xxxxxxxxxx>
> diff --git a/fs/f2fs/data.c b/fs/f2fs/data.c
> index f5f2b7233982..23486486eab2 100644
> --- a/fs/f2fs/data.c
> +++ b/fs/f2fs/data.c
> @@ -4153,6 +4153,8 @@ static int f2fs_iomap_begin(struct inode *inode, loff_t offset, loff_t length,
> if ((inode->i_state & I_DIRTY_DATASYNC) ||
> offset + length > i_size_read(inode))
> iomap->flags |= IOMAP_F_DIRTY;
> + if (F2FS_I_SB(inode)->no_fua_dio)
> + iomap->flags |= IOMAP_F_DIRTY;
This is overloading the IOMAP_F_DIRTY flag to mean something other than dirty.
Perhaps this flag needs to be renamed, or a new flag should be added?
> diff --git a/fs/f2fs/f2fs.h b/fs/f2fs/f2fs.h
> index e10838879538..c2400ea0080b 100644
> --- a/fs/f2fs/f2fs.h
> +++ b/fs/f2fs/f2fs.h
> @@ -1671,6 +1671,7 @@ struct f2fs_sb_info {
> int dir_level; /* directory level */
> int readdir_ra; /* readahead inode in readdir */
> u64 max_io_bytes; /* max io bytes to merge IOs */
> + int no_fua_dio; /* avoid FUA in DIO */
Make this a bool?
> diff --git a/fs/f2fs/sysfs.c b/fs/f2fs/sysfs.c
> index 4c50aedd5144..24d628ca92cc 100644
> --- a/fs/f2fs/sysfs.c
> +++ b/fs/f2fs/sysfs.c
> @@ -771,6 +771,7 @@ F2FS_RW_ATTR(F2FS_SBI, f2fs_sb_info, iostat_period_ms, iostat_period_ms);
> #endif
> F2FS_RW_ATTR(F2FS_SBI, f2fs_sb_info, readdir_ra, readdir_ra);
> F2FS_RW_ATTR(F2FS_SBI, f2fs_sb_info, max_io_bytes, max_io_bytes);
> +F2FS_RW_ATTR(F2FS_SBI, f2fs_sb_info, no_fua_dio, no_fua_dio);
> F2FS_RW_ATTR(F2FS_SBI, f2fs_sb_info, gc_pin_file_thresh, gc_pin_file_threshold);
> F2FS_RW_ATTR(F2FS_SBI, f2fs_super_block, extension_list, extension_list);
> #ifdef CONFIG_F2FS_FAULT_INJECTION
> @@ -890,6 +891,7 @@ static struct attribute *f2fs_attrs[] = {
> #endif
> ATTR_LIST(readdir_ra),
> ATTR_LIST(max_io_bytes),
> + ATTR_LIST(no_fua_dio),
Where is it validated that only valid values (0 or 1) can be written to this
file?
- Eric
