diff options
| author | Eric Sandeen <sandeen@redhat.com> | 2008-08-02 21:21:08 -0400 |
|---|---|---|
| committer | Theodore Ts'o <tytso@mit.edu> | 2008-08-02 21:21:08 -0400 |
| commit | b5f10eed8125702929e57cca7e5956b1b9b6d015 (patch) | |
| tree | e5b38a6f654baea3658bf100320a4d66387988a3 /fs/ext4/super.c | |
| parent | e29d1cde63be0b5f1739416b5574a83c34bf8eeb (diff) | |
| download | lwn-b5f10eed8125702929e57cca7e5956b1b9b6d015.tar.gz lwn-b5f10eed8125702929e57cca7e5956b1b9b6d015.zip | |
ext4: lock block groups when initializing
I noticed when filling a 1T filesystem with 4 threads using the
fs_mark benchmark:
fs_mark -d /mnt/test -D 256 -n 100000 -t 4 -s 20480 -F -S 0
that I occasionally got checksum mismatch errors:
EXT4-fs error (device sdb): ext4_init_inode_bitmap: Checksum bad for group 6935
etc. I'd reliably get 4-5 of them during the run.
It appears that the problem is likely a race to init the bg's
when the uninit_bg feature is enabled.
With the patch below, which adds sb_bgl_locking around initialization,
I was able to complete several runs with no errors or warnings.
Signed-off-by: Eric Sandeen <sandeen@redhat.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Diffstat (limited to 'fs/ext4/super.c')
| -rw-r--r-- | fs/ext4/super.c | 2 |
1 files changed, 2 insertions, 0 deletions
diff --git a/fs/ext4/super.c b/fs/ext4/super.c index 876e1c620365..511997ef6f0e 100644 --- a/fs/ext4/super.c +++ b/fs/ext4/super.c @@ -1621,6 +1621,7 @@ static int ext4_check_descriptors(struct super_block *sb) "(block %llu)!", i, inode_table); return 0; } + spin_lock(sb_bgl_lock(sbi, i)); if (!ext4_group_desc_csum_verify(sbi, i, gdp)) { printk(KERN_ERR "EXT4-fs: ext4_check_descriptors: " "Checksum for group %lu failed (%u!=%u)\n", @@ -1629,6 +1630,7 @@ static int ext4_check_descriptors(struct super_block *sb) if (!(sb->s_flags & MS_RDONLY)) return 0; } + spin_unlock(sb_bgl_lock(sbi, i)); if (!flexbg_flag) first_block += EXT4_BLOCKS_PER_GROUP(sb); } |