Re: [f2fs-dev] [PATCH 08/10] f2fs: relax async discard commands more

From: Chao Yu
Date: Thu Jan 05 2017 - 03:55:34 EST


Hi Jaegeuk,

I can see patch named ("f2fs: call f2fs_wait_all_discard_bio for an error case")
was merged in dev-test, but I think it's no needed to change error case handling
like this since f2fs_wait_all_discard_bio should always be called after
clear_prefree_segments.

Thanks,

On 2017/1/5 11:19, Chao Yu wrote:
> On 2017/1/4 17:29, Chao Yu wrote:
>> On 2016/12/31 2:51, Jaegeuk Kim wrote:
>>> This patch relaxes async discard commands to avoid waiting its end_io during
>>> checkpoint.
>>> Instead of waiting them during checkpoint, it will be done when actually reusing
>>> them.
>>>
>>> Test on initial partition of nvme drive.
>>>
>>> # time fstrim /mnt/test
>>>
>>> Before : 6.158s
>>> After : 4.822s
>>>
>>> Signed-off-by: Jaegeuk Kim <jaegeuk@xxxxxxxxxx>
>>
>> Reviewed-by: Chao Yu <yuchao0@xxxxxxxxxx>
>>
>> One comment below,
>
> I still have a comment on this patch.
>
>>> -void f2fs_wait_all_discard_bio(struct f2fs_sb_info *sbi)
>>> +/* This should be covered by global mutex, &sit_i->sentry_lock */
>>> +void f2fs_wait_discard_bio(struct f2fs_sb_info *sbi, unsigned int segno)
>>> {
>>> struct list_head *wait_list = &(SM_I(sbi)->wait_list);
>>> struct bio_entry *be, *tmp;
>>> @@ -646,7 +650,15 @@ void f2fs_wait_all_discard_bio(struct f2fs_sb_info *sbi)
>>> struct bio *bio = be->bio;
>>> int err;
>>>
>>> - wait_for_completion_io(&be->event);
>>> + if (!completion_done(&be->event)) {
>>> + if ((be->start_segno >= segno &&
>>> + be->end_segno <= segno) ||
>>
>> segno >= be->start_segno && segno < be->end_segno ?
>
> Can you check this?
>
> Thanks,
>