Re: [PATCH] f2fs: let f2fs also gc atomic file to avoid loop gc

[Yunlong Song]

Is there any problem if just deleting the judgement condition in this patch?

On 2017/11/8 17:28, Chao Yu wrote:
> On 2017/11/8 10:34, Yunlong Song wrote:
> > If some files are opened with atomic flag and have not commited yet, at
> > the same time, if all the target victim segments have at least one page
> > of these atomic files, then f2fs gc will fail to do gc and hangs in the
> > process of go to gc_more, since gc_date_segment will not move any data
> > and get_valid_blocks will never be 0, then do_garbage_collect will
> > always return 0.
> Oh, I added this judgment condition to avoid ruining atomic write by data
> GC, could we find another way to solve this issue? BTW, if there is direct
> IO, we will also skip data segment GC.
>
> Thanks,
>
> > Signed-off-by: Yunlong Song <yunlong.song@xxxxxxxxxx>
> > ---
> >   fs/f2fs/gc.c | 6 ------
> >   1 file changed, 6 deletions(-)
> >
> > diff --git a/fs/f2fs/gc.c b/fs/f2fs/gc.c
> > index 5d5bba4..3fdcd04 100644
> > --- a/fs/f2fs/gc.c
> > +++ b/fs/f2fs/gc.c
> > @@ -621,9 +621,6 @@ static void move_data_block(struct inode *inode, block_t bidx,
> >   	if (!check_valid_map(F2FS_I_SB(inode), segno, off))
> >   		goto out;
> >   
> > -	if (f2fs_is_atomic_file(inode))
> > -		goto out;
> > -
> >   	set_new_dnode(&dn, inode, NULL, NULL, 0);
> >   	err = get_dnode_of_data(&dn, bidx, LOOKUP_NODE);
> >   	if (err)
> > @@ -718,9 +715,6 @@ static void move_data_page(struct inode *inode, block_t bidx, int gc_type,
> >   	if (!check_valid_map(F2FS_I_SB(inode), segno, off))
> >   		goto out;
> >   
> > -	if (f2fs_is_atomic_file(inode))
> > -		goto out;
> > -
> >   	if (gc_type == BG_GC) {
> >   		if (PageWriteback(page))
> >   			goto out;
>
> .

--
Thanks,
Yunlong Song