Re: [PATCH 4/4] f2fs: fix to spread clear_cold_data()

[Chao Yu]

On 2018/7/29 10:44, Jaegeuk Kim wrote:
> On 07/29, Chao Yu wrote:
>> On 2018/7/29 10:00, Jaegeuk Kim wrote:
>>> On 07/27, Chao Yu wrote:
>>>> We need to drop PG_checked flag on page as well when we clear PG_uptodate
>>>> flag, in order to avoid treating the page as GCing one later.
>>>
>>> What do you mean "treating the page as GCing one"?
>>
>> I mean if PG_checked flag in page is not cleared, allocator will make it goes
>> into cold area.
>>
>> static int __get_segment_type_6(struct f2fs_io_info *fio)
>> ...
>> 		if (is_cold_data(fio->page) || file_is_cold(inode))
>> 			return CURSEG_COLD_DATA;
> 
> This will come only when page is dirty. So, it'd better to clear this in
> f2fs_set_data_page_dirty()? set_cold_data() is called after set_page_dirty().

Looks fine, let me send v2.

Thanks,

> 
>>
>> Thanks,
>>
>>>
>>>>
>>>> Signed-off-by: Weichao Guo <guoweichao@xxxxxxxxxx>
>>>> Signed-off-by: Chao Yu <yuchao0@xxxxxxxxxx>
>>>> ---
>>>>  fs/f2fs/data.c    | 8 +++++++-
>>>>  fs/f2fs/dir.c     | 1 +
>>>>  fs/f2fs/segment.c | 4 +++-
>>>>  3 files changed, 11 insertions(+), 2 deletions(-)
>>>>
>>>> diff --git a/fs/f2fs/data.c b/fs/f2fs/data.c
>>>> index a29f3162b887..2817e2f4eb17 100644
>>>> --- a/fs/f2fs/data.c
>>>> +++ b/fs/f2fs/data.c
>>>> @@ -1768,6 +1768,7 @@ int f2fs_do_write_data_page(struct f2fs_io_info *fio)
>>>>  	/* This page is already truncated */
>>>>  	if (fio->old_blkaddr == NULL_ADDR) {
>>>>  		ClearPageUptodate(page);
>>>> +		clear_cold_data(page);
>>>>  		goto out_writepage;
>>>>  	}
>>>>  got_it:
>>>> @@ -1943,8 +1944,10 @@ static int __write_data_page(struct page *page, bool *submitted,
>>>>  
>>>>  out:
>>>>  	inode_dec_dirty_pages(inode);
>>>> -	if (err)
>>>> +	if (err) {
>>>>  		ClearPageUptodate(page);
>>>> +		clear_cold_data(page);
>>>> +	}
>>>>  
>>>>  	if (wbc->for_reclaim) {
>>>>  		f2fs_submit_merged_write_cond(sbi, inode, 0, page->index, DATA);
>>>> @@ -2534,6 +2537,8 @@ void f2fs_invalidate_page(struct page *page, unsigned int offset,
>>>>  		}
>>>>  	}
>>>>  
>>>> +	clear_cold_data(page);
>>>> +
>>>>  	/* This is atomic written page, keep Private */
>>>>  	if (IS_ATOMIC_WRITTEN_PAGE(page))
>>>>  		return f2fs_drop_inmem_page(inode, page);
>>>> @@ -2552,6 +2557,7 @@ int f2fs_release_page(struct page *page, gfp_t wait)
>>>>  	if (IS_ATOMIC_WRITTEN_PAGE(page))
>>>>  		return 0;
>>>>  
>>>> +	clear_cold_data(page);
>>>>  	set_page_private(page, 0);
>>>>  	ClearPagePrivate(page);
>>>>  	return 1;
>>>> diff --git a/fs/f2fs/dir.c b/fs/f2fs/dir.c
>>>> index 7f955c4e86a4..1e4a4122eb0c 100644
>>>> --- a/fs/f2fs/dir.c
>>>> +++ b/fs/f2fs/dir.c
>>>> @@ -734,6 +734,7 @@ void f2fs_delete_entry(struct f2fs_dir_entry *dentry, struct page *page,
>>>>  		clear_page_dirty_for_io(page);
>>>>  		ClearPagePrivate(page);
>>>>  		ClearPageUptodate(page);
>>>> +		clear_cold_data(page);
>>>>  		inode_dec_dirty_pages(dir);
>>>>  		f2fs_remove_dirty_inode(dir);
>>>>  	}
>>>> diff --git a/fs/f2fs/segment.c b/fs/f2fs/segment.c
>>>> index 58abbdc53561..4d83961745e6 100644
>>>> --- a/fs/f2fs/segment.c
>>>> +++ b/fs/f2fs/segment.c
>>>> @@ -267,8 +267,10 @@ static int __revoke_inmem_pages(struct inode *inode,
>>>>  		}
>>>>  next:
>>>>  		/* we don't need to invalidate this in the sccessful status */
>>>> -		if (drop || recover)
>>>> +		if (drop || recover) {
>>>>  			ClearPageUptodate(page);
>>>> +			clear_cold_data(page);
>>>> +		}
>>>>  		set_page_private(page, 0);
>>>>  		ClearPagePrivate(page);
>>>>  		f2fs_put_page(page, 1);
>>>> -- 
>>>> 2.18.0.rc1