Re: [PATCH] f2fs: free_user_blocks should use reserved_segments instead

From: Yunlong Song
Date: Tue Aug 15 2017 - 03:18:37 EST


Consider this, I have sent another patch v2, please review.

The part (overprovision_segments - reserved_segments) can still be used for LFS
in some case, e.g., there are lots of invalid block from dirty segments, then
the part (overprovision_segments - reserved_segments) can be safely used. So
free_use_blocks should use reserved_segments instead, rather than directly use
overprovision_segments. BTW, we also add the constraint of sbi->reserved_blocks.


On 2017/8/15 11:32, Jaegeuk Kim wrote:
On 08/14, Yunlong Song wrote:
The part (overprovision_segments - reserved_segments) can still be used for LFS,
so free_use_blocks should use reserved_segments instead, rather than use
overprovision_segments.

Signed-off-by: Yunlong Song <yunlong.song@xxxxxxxxxx>
---
fs/f2fs/gc.h | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/fs/f2fs/gc.h b/fs/f2fs/gc.h
index 9325191..6258305 100644
--- a/fs/f2fs/gc.h
+++ b/fs/f2fs/gc.h
@@ -49,10 +49,10 @@ struct gc_inode_list {
*/
static inline block_t free_user_blocks(struct f2fs_sb_info *sbi)
NAK. This gives user-visible block count.

{
- if (free_segments(sbi) < overprovision_segments(sbi))
+ if (free_segments(sbi) < reserved_segments(sbi))
return 0;
else
- return (free_segments(sbi) - overprovision_segments(sbi))
+ return (free_segments(sbi) - reserved_segments(sbi))
<< sbi->log_blocks_per_seg;
}
--
1.8.5.2
.


--
Thanks,
Yunlong Song