Re: [PATCH] f2fs: prevent meta updates while checkpoint is in progress

From: Jaegeuk Kim
Date: Mon Mar 30 2020 - 23:54:23 EST


On 03/26, Sahitya Tummala wrote:
> allocate_segment_for_resize() can cause metapage updates if
> it requires to change the current node/data segments for resizing.
> Stop these meta updates when there is a checkpoint already
> in progress to prevent inconsistent CP data.

I'd prefer to use f2fs_lock_op() in bigger coverage.

>
> Signed-off-by: Sahitya Tummala <stummala@xxxxxxxxxxxxxx>
> ---
> fs/f2fs/gc.c | 2 ++
> 1 file changed, 2 insertions(+)
>
> diff --git a/fs/f2fs/gc.c b/fs/f2fs/gc.c
> index 5bca560..6122bad 100644
> --- a/fs/f2fs/gc.c
> +++ b/fs/f2fs/gc.c
> @@ -1399,8 +1399,10 @@ static int free_segment_range(struct f2fs_sb_info *sbi, unsigned int start,
> int err = 0;
>
> /* Move out cursegs from the target range */
> + f2fs_lock_op(sbi);
> for (type = CURSEG_HOT_DATA; type < NR_CURSEG_TYPE; type++)
> allocate_segment_for_resize(sbi, type, start, end);
> + f2fs_unlock_op(sbi);
>
> /* do GC to move out valid blocks in the range */
> for (segno = start; segno <= end; segno += sbi->segs_per_sec) {
> --
> Qualcomm India Private Limited, on behalf of Qualcomm Innovation Center, Inc.
> Qualcomm Innovation Center, Inc. is a member of Code Aurora Forum, a Linux Foundation Collaborative Project.