From b5f10eed8125702929e57cca7e5956b1b9b6d015 Mon Sep 17 00:00:00 2001 From: Eric Sandeen Date: Sat, 2 Aug 2008 21:21:08 -0400 Subject: 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 Signed-off-by: Theodore Ts'o --- fs/ext4/ialloc.c | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-) (limited to 'fs/ext4/ialloc.c') diff --git a/fs/ext4/ialloc.c b/fs/ext4/ialloc.c index 09cdcd5914d0..655e760212b8 100644 --- a/fs/ext4/ialloc.c +++ b/fs/ext4/ialloc.c @@ -118,12 +118,15 @@ ext4_read_inode_bitmap(struct super_block *sb, ext4_group_t block_group) if (bh_uptodate_or_lock(bh)) return bh; + spin_lock(sb_bgl_lock(EXT4_SB(sb), block_group)); if (desc->bg_flags & cpu_to_le16(EXT4_BG_INODE_UNINIT)) { ext4_init_inode_bitmap(sb, bh, block_group, desc); set_buffer_uptodate(bh); unlock_buffer(bh); + spin_unlock(sb_bgl_lock(EXT4_SB(sb), block_group)); return bh; } + spin_unlock(sb_bgl_lock(EXT4_SB(sb), block_group)); if (bh_submit_read(bh) < 0) { put_bh(bh); ext4_error(sb, __func__, @@ -735,7 +738,7 @@ got: /* When marking the block group with * ~EXT4_BG_INODE_UNINIT we don't want to depend - * on the value of bg_itable_unsed even though + * on the value of bg_itable_unused even though * mke2fs could have initialized the same for us. * Instead we calculated the value below */ -- cgit v1.2.1