Re: [f2fs-dev] [PATCH] f2fs: add a way to turn off ipu bio cache

[Chao Yu <yuchao0@huawei.com>]

On 2020/1/7 10:07, Jaegeuk Kim wrote:
> Setting 0x40 in /sys/fs/f2fs/dev/ipu_policy gives a way to turn off
> bio cache, which is useufl to check whether block layer using hardware
> encryption engine merges IOs correctly.
> 
> Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
> ---
>  Documentation/filesystems/f2fs.txt | 1 +
>  fs/f2fs/segment.c                  | 2 +-
>  fs/f2fs/segment.h                  | 1 +
>  3 files changed, 3 insertions(+), 1 deletion(-)
> 
> diff --git a/Documentation/filesystems/f2fs.txt b/Documentation/filesystems/f2fs.txt
> index 41b5aa94b30f..cd93bcc34726 100644
> --- a/Documentation/filesystems/f2fs.txt
> +++ b/Documentation/filesystems/f2fs.txt
> @@ -335,6 +335,7 @@ Files in /sys/fs/f2fs/<devname>
>                                 0x01: F2FS_IPU_FORCE, 0x02: F2FS_IPU_SSR,
>                                 0x04: F2FS_IPU_UTIL,  0x08: F2FS_IPU_SSR_UTIL,
>                                 0x10: F2FS_IPU_FSYNC.

. -> ,

Reviewed-by: Chao Yu <yuchao0@huawei.com>

Thanks,

> +			       0x40: F2FS_IPU_NOCACHE disables bio caches.
>  
>   min_ipu_util                 This parameter controls the threshold to trigger
>                                in-place-updates. The number indicates percentage
> diff --git a/fs/f2fs/segment.c b/fs/f2fs/segment.c
> index a9519532c029..311fe4937f6a 100644
> --- a/fs/f2fs/segment.c
> +++ b/fs/f2fs/segment.c
> @@ -3289,7 +3289,7 @@ int f2fs_inplace_write_data(struct f2fs_io_info *fio)
>  
>  	stat_inc_inplace_blocks(fio->sbi);
>  
> -	if (fio->bio)
> +	if (fio->bio && !(SM_I(sbi)->ipu_policy & (1 << F2FS_IPU_NOCACHE)))
>  		err = f2fs_merge_page_bio(fio);
>  	else
>  		err = f2fs_submit_page_bio(fio);
> diff --git a/fs/f2fs/segment.h b/fs/f2fs/segment.h
> index a1b3951367cd..02e620470eef 100644
> --- a/fs/f2fs/segment.h
> +++ b/fs/f2fs/segment.h
> @@ -623,6 +623,7 @@ enum {
>  	F2FS_IPU_SSR_UTIL,
>  	F2FS_IPU_FSYNC,
>  	F2FS_IPU_ASYNC,
> +	F2FS_IPU_NOCACHE,
>  };
>  
>  static inline unsigned int curseg_segno(struct f2fs_sb_info *sbi,
>