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

[Chao Yu <yuchao0@huawei.com>]

On 2020/1/9 7:18, Jaegeuk Kim wrote:
> On 01/08, Chao Yu wrote:
>> On 2020/1/8 20:04, Jaegeuk Kim wrote:
>>> On 01/08, Chao Yu wrote:
>>>> 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.
>>>>
>>>> . -> ,
>>>
>>> Actually, we can't do it. I revised it a bit instead.
>>
>> One more question, why skipping 0x20 bit position?
> 
> It seems original patch missed to add comment.
> 
>>From f9447095de55a3cda1023a37a5e1cb6dd2f54ebb Mon Sep 17 00:00:00 2001
> From: Jaegeuk Kim <jaegeuk@kernel.org>
> Date: Wed, 8 Jan 2020 15:10:02 -0800
> Subject: [PATCH] f2fs: update f2fs document regarding to fsync_mode
> 
> This patch adds missing fsync_mode entry in f2fs document.
> 
> Fixes: 04485987f053 ("f2fs: introduce async IPU policy")
> Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
Reviewed-by: Chao Yu <yuchao0@huawei.com>

Thanks,