Re: [PATCH v2 6/6] f2fs: give up CP_TRIMMED_FLAG if it drops discards

[Chao Yu <yuchao0@huawei.com>]

On 2017/10/25 13:45, Jaegeuk Kim wrote:
> On 10/24, Chao Yu wrote:
>> On 2017/10/24 20:46, Jaegeuk Kim wrote:
>>> On 10/24, Chao Yu wrote:
>>>> Hi Jaegeuk,
>>>>
>>>> On 2017/10/4 9:08, Chao Yu wrote:
>>>>> From: Chao Yu <yuchao0@huawei.com>
>>>>>
>>>>> In ->umount, once we drop remained discard entries, we should not
>>>>> set CP_TRIMMED_FLAG with another checkpoint.
>>>>>
>>>>> Signed-off-by: Chao Yu <yuchao0@huawei.com>
>>>>> ---
>>>>> v2:
>>>>> - rebase on last codes of Jaegeuk's dev-test branch.
>>>>>  fs/f2fs/f2fs.h    |  2 +-
>>>>>  fs/f2fs/segment.c | 15 +++++++++++----
>>>>>  fs/f2fs/super.c   |  5 +++--
>>>>>  3 files changed, 15 insertions(+), 7 deletions(-)
>>>>>
>>>>> diff --git a/fs/f2fs/f2fs.h b/fs/f2fs/f2fs.h
>>>>> index f274805e231d..c85f49c41003 100644
>>>>> --- a/fs/f2fs/f2fs.h
>>>>> +++ b/fs/f2fs/f2fs.h
>>>>> @@ -2565,7 +2565,7 @@ void init_discard_policy(struct discard_policy *dpolicy, int discard_type,
>>>>>  						unsigned int granularity);
>>>>>  void refresh_sit_entry(struct f2fs_sb_info *sbi, block_t old, block_t new);
>>>>>  void stop_discard_thread(struct f2fs_sb_info *sbi);
>>>>> -void f2fs_wait_discard_bios(struct f2fs_sb_info *sbi);
>>>>> +bool f2fs_wait_discard_bios(struct f2fs_sb_info *sbi);
>>>>>  void clear_prefree_segments(struct f2fs_sb_info *sbi, struct cp_control *cpc);
>>>>>  void release_discard_addrs(struct f2fs_sb_info *sbi);
>>>>>  int npages_for_summary_flush(struct f2fs_sb_info *sbi, bool for_ra);
>>>>> diff --git a/fs/f2fs/segment.c b/fs/f2fs/segment.c
>>>>> index 4a108321233d..bfbcff8339c5 100644
>>>>> --- a/fs/f2fs/segment.c
>>>>> +++ b/fs/f2fs/segment.c
>>>>> @@ -1196,12 +1196,13 @@ static int __issue_discard_cmd(struct f2fs_sb_info *sbi,
>>>>>  	return issued;
>>>>>  }
>>>>>  
>>>>> -static void __drop_discard_cmd(struct f2fs_sb_info *sbi)
>>>>> +static bool __drop_discard_cmd(struct f2fs_sb_info *sbi)
>>>>>  {
>>>>>  	struct discard_cmd_control *dcc = SM_I(sbi)->dcc_info;
>>>>>  	struct list_head *pend_list;
>>>>>  	struct discard_cmd *dc, *tmp;
>>>>>  	int i;
>>>>> +	bool dropped = false;
>>>>>  
>>>>>  	mutex_lock(&dcc->cmd_lock);
>>>>>  	for (i = MAX_PLIST_NUM - 1; i >= 0; i--) {
>>>>> @@ -1209,9 +1210,12 @@ static void __drop_discard_cmd(struct f2fs_sb_info *sbi)
>>>>>  		list_for_each_entry_safe(dc, tmp, pend_list, list) {
>>>>>  			f2fs_bug_on(sbi, dc->state != D_PREP);
>>>>>  			__remove_discard_cmd(sbi, dc);
>>>>> +			dropped = true;
>>>>>  		}
>>>>>  	}
>>>>>  	mutex_unlock(&dcc->cmd_lock);
>>>>> +
>>>>> +	return dropped;
>>>>>  }
>>>>>  
>>>>>  static void __wait_one_discard_bio(struct f2fs_sb_info *sbi,
>>>>> @@ -1306,15 +1310,18 @@ void stop_discard_thread(struct f2fs_sb_info *sbi)
>>>>>  }
>>>>>  
>>>>>  /* This comes from f2fs_put_super */
>>>>> -void f2fs_wait_discard_bios(struct f2fs_sb_info *sbi)
>>>>> +bool f2fs_wait_discard_bios(struct f2fs_sb_info *sbi)
>>>>>  {
>>>>>  	struct discard_cmd_control *dcc = SM_I(sbi)->dcc_info;
>>>>>  	struct discard_policy dpolicy;
>>>>> +	bool dropped;
>>>>>  
>>>>>  	init_discard_policy(&dpolicy, DPOLICY_UMOUNT, dcc->discard_granularity);
>>>>>  	__issue_discard_cmd(sbi, &dpolicy);
>>>>> -	__drop_discard_cmd(sbi);
>>>>> +	dropped = __drop_discard_cmd(sbi);
>>>>>  	__wait_all_discard_cmd(sbi, &dpolicy);
>>>>> +
>>>>> +	return dropped;
>>>>>  }
>>>>>  
>>>>>  static int issue_discard_thread(void *data)
>>>>> @@ -1659,7 +1666,7 @@ void init_discard_policy(struct discard_policy *dpolicy,
>>>>>  		dpolicy->max_interval = DEF_MAX_DISCARD_ISSUE_TIME;
>>>>>  		dpolicy->max_requests = DEF_MAX_DISCARD_REQUEST;
>>>>>  		dpolicy->io_aware_gran = MAX_PLIST_NUM;
>>>>> -		dpolicy->io_aware = false;
>>>>> +		dpolicy->io_aware = true;
>>>>
>>>> I notice this change should not belong to this patch, could you please help to
>>>> move this into "f2fs: split discard policy" in your branch?
>>>
>>> Yup, done. Could you check it in dev-test?
>>
>> I didn't find it, did you forget to push to that branch?
> 
> Yup, I pushed it. :)

I've checked that, it's OK to me now. :)

Thanks,

> 
> Thanks,
> 
>>
>> Thanks,
>>
>>>
>>> Thanks,
>>>
>>>>
>>>> Thanks,
>>>>
>>>>>  	} else if (discard_type == DPOLICY_FSTRIM) {
>>>>>  		dpolicy->max_requests = DEF_MAX_DISCARD_REQUEST;
>>>>>  		dpolicy->io_aware_gran = MAX_PLIST_NUM;
>>>>> diff --git a/fs/f2fs/super.c b/fs/f2fs/super.c
>>>>> index a13269d1a1f0..1d68c18a487b 100644
>>>>> --- a/fs/f2fs/super.c
>>>>> +++ b/fs/f2fs/super.c
>>>>> @@ -807,6 +807,7 @@ static void f2fs_put_super(struct super_block *sb)
>>>>>  {
>>>>>  	struct f2fs_sb_info *sbi = F2FS_SB(sb);
>>>>>  	int i;
>>>>> +	bool dropped;
>>>>>  
>>>>>  	f2fs_quota_off_umount(sb);
>>>>>  
>>>>> @@ -827,9 +828,9 @@ static void f2fs_put_super(struct super_block *sb)
>>>>>  	}
>>>>>  
>>>>>  	/* be sure to wait for any on-going discard commands */
>>>>> -	f2fs_wait_discard_bios(sbi, true);
>>>>> +	dropped = f2fs_wait_discard_bios(sbi);
>>>>>  
>>>>> -	if (f2fs_discard_en(sbi) && !sbi->discard_blks) {
>>>>> +	if (f2fs_discard_en(sbi) && !sbi->discard_blks && !dropped) {
>>>>>  		struct cp_control cpc = {
>>>>>  			.reason = CP_UMOUNT | CP_TRIMMED,
>>>>>  		};
>>>>>
> 
> .
>