2017-08-26 11:47:34

by Yunlong Song

Subject: [PATCH] f2fs: collect prefree segments to avoild write checkpoint fail

In come corner case, the reserved segments are used to do gc, and there are
not enough free segments for write checkpoint to finish its job, then the
gc process will fail to change the prefree segments to free segments.

Signed-off-by: Yunlong Song <[email protected]>
---
fs/f2fs/gc.c | 7 +++++++
1 file changed, 7 insertions(+)

diff --git a/fs/f2fs/gc.c b/fs/f2fs/gc.c
index cd147e7..c8a828f 100644
--- a/fs/f2fs/gc.c
+++ b/fs/f2fs/gc.c
@@ -1056,6 +1056,13 @@ int f2fs_gc(struct f2fs_sb_info *sbi, bool sync,
if (!sync) {
if (has_not_enough_free_secs(sbi, sec_freed, 0)) {
segno = NULL_SEGNO;
+ if (prefree_segments(sbi) &&
+ has_not_enough_free_secs(sbi,
+ reserved_sections(sbi), 0)) {
+ ret = write_checkpoint(sbi, &cpc);
+ if (ret)
+ goto stop;
+ }
goto gc_more;
}

--
1.8.5.2

2017-08-28 09:53:07

by Chao Yu

Subject: Re: [PATCH] f2fs: collect prefree segments to avoild write checkpoint fail

Hi Yunlong,

On 2017/8/26 19:46, Yunlong Song wrote:
> In come corner case, the reserved segments are used to do gc, and there are
> not enough free segments for write checkpoint to finish its job, then the
> gc process will fail to change the prefree segments to free segments.

How about doing investigate that why we haven't enough free segment for GC?

Thanks,

>
> Signed-off-by: Yunlong Song <[email protected]>
> ---
> fs/f2fs/gc.c | 7 +++++++
> 1 file changed, 7 insertions(+)
>
> diff --git a/fs/f2fs/gc.c b/fs/f2fs/gc.c
> index cd147e7..c8a828f 100644
> --- a/fs/f2fs/gc.c
> +++ b/fs/f2fs/gc.c
> @@ -1056,6 +1056,13 @@ int f2fs_gc(struct f2fs_sb_info *sbi, bool sync,
> if (!sync) {
> if (has_not_enough_free_secs(sbi, sec_freed, 0)) {
> segno = NULL_SEGNO;
> + if (prefree_segments(sbi) &&
> + has_not_enough_free_secs(sbi,
> + reserved_sections(sbi), 0)) {
> + ret = write_checkpoint(sbi, &cpc);
> + if (ret)
> + goto stop;
> + }
> goto gc_more;
> }
>
>

2017-09-01 12:00:39

by Yunlong Song

Subject: [PATCH v2] f2fs: collect prefree segments to avoild write checkpoint fail

In come corner case, the reserved segments are used to do gc, and there are
not enough free segments for write checkpoint to finish its job, then the
gc process will fail to change the prefree segments to free segments.

Signed-off-by: Yunlong Song <[email protected]>
---
fs/f2fs/gc.c | 10 ++++++++++
1 file changed, 10 insertions(+)

diff --git a/fs/f2fs/gc.c b/fs/f2fs/gc.c
index cd147e7..6552b04 100644
--- a/fs/f2fs/gc.c
+++ b/fs/f2fs/gc.c
@@ -1056,6 +1056,16 @@ int f2fs_gc(struct f2fs_sb_info *sbi, bool sync,
if (!sync) {
if (has_not_enough_free_secs(sbi, sec_freed, 0)) {
segno = NULL_SEGNO;
+#ifndef CONFIG_F2FS_CHECK_FS
+ if (prefree_segments(sbi) &&
+ has_not_enough_free_secs(sbi,
+ reserved_sections(sbi), 0)) {
+ ret = write_checkpoint(sbi, &cpc);
+ if (ret)
+ goto stop;
+ sec_freed = 0;
+ }
+#endif
goto gc_more;
}

--
1.8.5.2