Re: [PATCH] f2fs: fix to account IO correctly
From: Jaegeuk Kim
Date: Thu Oct 18 2018 - 15:06:16 EST
On 10/17, Chao Yu wrote:
> Below race can cause reversed reference on F2FS_RD_DATA, there is
> the same issue in f2fs_submit_page_bio(), fix them by relocate
> __submit_bio() and inc_page_count.
>
> Thread A Thread B
> - f2fs_write_begin
> - f2fs_submit_page_read
> - __submit_bio
> - f2fs_read_end_io
> - __read_end_io
> - dec_page_count(, F2FS_RD_DATA)
> - inc_page_count(, F2FS_RD_DATA)
Let me integrate the change into the original patch and test a bit.
Thanks,
>
> Signed-off-by: Chao Yu <yuchao0@xxxxxxxxxx>
> ---
> fs/f2fs/data.c | 6 +++---
> 1 file changed, 3 insertions(+), 3 deletions(-)
>
> diff --git a/fs/f2fs/data.c b/fs/f2fs/data.c
> index c03bd0c2ed22..8b9240762156 100644
> --- a/fs/f2fs/data.c
> +++ b/fs/f2fs/data.c
> @@ -480,10 +480,10 @@ int f2fs_submit_page_bio(struct f2fs_io_info *fio)
> }
> bio_set_op_attrs(bio, fio->op, fio->op_flags);
>
> - __submit_bio(fio->sbi, bio, fio->type);
> -
> inc_page_count(fio->sbi, is_read_io(fio->op) ?
> __read_io_type(page): WB_DATA_TYPE(fio->page));
> +
> + __submit_bio(fio->sbi, bio, fio->type);
> return 0;
> }
>
> @@ -612,8 +612,8 @@ static int f2fs_submit_page_read(struct inode *inode, struct page *page,
> return -EFAULT;
> }
> ClearPageError(page);
> - __submit_bio(F2FS_I_SB(inode), bio, DATA);
> inc_page_count(F2FS_I_SB(inode), F2FS_RD_DATA);
> + __submit_bio(F2FS_I_SB(inode), bio, DATA);
> return 0;
> }
>
> --
> 2.18.0.rc1