From: Zhao Lei <zhaolei@xxxxxxxxxxxxxx>
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@xxxxxxxxxxxxxx>
---
fs/btrfs/extent-tree.c | 10 ++++++++++
1 file changed, 10 insertions(+)
diff --git a/fs/btrfs/extent-tree.c b/fs/btrfs/extent-tree.c
index 644468b..e04ea1f 100644
--- a/fs/btrfs/extent-tree.c
+++ b/fs/btrfs/extent-tree.c
@@ -9654,8 +9654,18 @@ void btrfs_delete_unused_bgs(struct btrfs_fs_info *fs_info)
mutex_unlock(&fs_info->unused_bg_unpin_mutex);
/* Reset pinned so btrfs_put_block_group doesn't complain */
+ spin_lock(&space_info->lock);
+ spin_lock(&block_group->lock);
+
+ space_info->bytes_pinned -= block_group->pinned;
+ space_info->bytes_readonly += block_group->pinned;
+ percpu_counter_add(&space_info->total_bytes_pinned,
+ -block_group->pinned);
block_group->pinned = 0;
+ spin_unlock(&block_group->lock);
+ spin_unlock(&space_info->lock);
+
/*
* Btrfs_remove_chunk will abort the transaction if things go
* horribly wrong.
--
1.8.5.1
--
To unsubscribe from this list: send the line "unsubscribe linux-btrfs" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
