btrfs: Set relative data on clear btrfs_block_group_cache->pinned
Bug1:
space_info->bytes_readonly was set to very large(negative) value in
btrfs_remove_block_group().
Reason:
Current code set block_group_cache->pinned = 0 in btrfs_delete_unused_bgs(),
but above space was not counted to space_info->bytes_readonly.
Then in btrfs_remove_block_group():
block_group->space_info->bytes_readonly -= block_group->key.offset;
We can see following value in trace:
btrfs_remove_block_group: pid=2677 comm=btrfs-cleaner WARNING: bytes_readonly=
12582912, key.offset=
134217728
Bug2:
space_info->total_bytes_pinned grow to value larger than fs size.
In a 1.2G fs, we can get following trace log:
at first:
ZL_DEBUG: add_pinned_bytes: pid=2710 comm=sync change total_bytes_pinned flags=1
869793792 +
95944704 =
965738496
after some op:
ZL_DEBUG: add_pinned_bytes: pid=2770 comm=sync change total_bytes_pinned flags=1
1780178944 +
95944704 =
1876123648
after some op:
ZL_DEBUG: add_pinned_bytes: pid=3193 comm=sync change total_bytes_pinned flags=1
2924568576 +
95551488 =
3020120064
...
Reason:
Similar to bug1, we also need to adjust space_info->total_bytes_pinned
in above code block.
Signed-off-by: Zhao Lei <zhaolei@cn.fujitsu.com>
Signed-off-by: Chris Mason <clm@fb.com>