diff options
author | Sheng Yong <shengyong@oppo.com> | 2024-07-10 04:26:59 +0300 |
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committer | Jaegeuk Kim <jaegeuk@kernel.org> | 2024-07-11 01:47:58 +0300 |
commit | e3a19972a49f61775e5e11ac43a663f28cdfb8b2 (patch) | |
tree | e65318c426cff5275f99a8e84c63955280ed954b /fs/f2fs/segment.c | |
parent | f06c0f82e38bbda7264d6ef3c90045ad2810e0f3 (diff) | |
download | linux-e3a19972a49f61775e5e11ac43a663f28cdfb8b2.tar.xz |
f2fs: only fragment segment in the same section
When new_curseg() is allocating a new segment, if mode=fragment:xxx is
switched on in large section scenario, __get_next_segno() will select
the next segno randomly in the range of [0, maxsegno] in order to
fragment segments.
If the candidate segno is free, get_new_segment() will use it directly
as the new segment.
However, if the section of the candidate is not empty, and some other
segments have already been used, and have a different type (e.g NODE)
with the candidate (e.g DATA), GC will complain inconsistent segment
type later.
This could be reproduced by the following steps:
dd if=/dev/zero of=test.img bs=1M count=10240
mkfs.f2fs -s 128 test.img
mount -t f2fs test.img /mnt -o mode=fragment:block
echo 1 > /sys/fs/f2fs/loop0/max_fragment_chunk
echo 512 > /sys/fs/f2fs/loop0/max_fragment_hole
dd if=/dev/zero of=/mnt/testfile bs=4K count=100
umount /mnt
F2FS-fs (loop0): Inconsistent segment (4377) type [0, 1] in SSA and SIT
In order to allow simulating segment fragmentation in large section
scenario, this patch reduces the candidate range:
* if curseg is the last segment in the section, return curseg->segno
to make get_new_segment() itself find the next free segment.
* if curseg is in the middle of the section, select candicate randomly
in the range of [curseg + 1, last_seg_in_the_same_section] to keep
type consistent.
Reviewed-by: Chao Yu <chao@kernel.org>
Signed-off-by: Sheng Yong <shengyong@oppo.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
Diffstat (limited to 'fs/f2fs/segment.c')
-rw-r--r-- | fs/f2fs/segment.c | 14 |
1 files changed, 11 insertions, 3 deletions
diff --git a/fs/f2fs/segment.c b/fs/f2fs/segment.c index 4db1add43e36..64b11d88a21c 100644 --- a/fs/f2fs/segment.c +++ b/fs/f2fs/segment.c @@ -2784,11 +2784,19 @@ static unsigned int __get_next_segno(struct f2fs_sb_info *sbi, int type) unsigned short seg_type = curseg->seg_type; sanity_check_seg_type(sbi, seg_type); - if (f2fs_need_rand_seg(sbi)) - return get_random_u32_below(MAIN_SECS(sbi) * SEGS_PER_SEC(sbi)); + if (__is_large_section(sbi)) { + if (f2fs_need_rand_seg(sbi)) { + unsigned int hint = GET_SEC_FROM_SEG(sbi, curseg->segno); - if (__is_large_section(sbi)) + if (GET_SEC_FROM_SEG(sbi, curseg->segno + 1) != hint) + return curseg->segno; + return get_random_u32_inclusive(curseg->segno + 1, + GET_SEG_FROM_SEC(sbi, hint + 1) - 1); + } return curseg->segno; + } else if (f2fs_need_rand_seg(sbi)) { + return get_random_u32_below(MAIN_SECS(sbi) * SEGS_PER_SEC(sbi)); + } /* inmem log may not locate on any segment after mount */ if (!curseg->inited) |