btrfs: remove lockdep classes for the fs tree

We have this weird problem where our lockdep class is set after we
read a tree block, which can race with concurrent readers and result in
erroneous lockdep errors.  We want to set the lockdep class at
allocation time if possible, but in certain cases we may not have the
actual root owner, such as with relocation or any backref lookups.  This
is only really a problem for reference counted trees, because all other
trees have their root reference set in their extent reference.  Remove
the fs tree specific lock class.  We need to still keep the reloc tree
one, it's still reference counted, because replace_path will lock the
reloc tree and the destination tree, and if they're both set to
tree-<level> we'll have issues.

Reviewed-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
This commit is contained in:
Josef Bacik 2020-11-05 10:45:08 -05:00 committed by David Sterba
parent 3e48d8d254
commit 416e3445ef

View File

@ -173,7 +173,6 @@ static struct btrfs_lockdep_keyset {
{ .id = BTRFS_EXTENT_TREE_OBJECTID, DEFINE_NAME("extent") },
{ .id = BTRFS_CHUNK_TREE_OBJECTID, DEFINE_NAME("chunk") },
{ .id = BTRFS_DEV_TREE_OBJECTID, DEFINE_NAME("dev") },
{ .id = BTRFS_FS_TREE_OBJECTID, DEFINE_NAME("fs") },
{ .id = BTRFS_CSUM_TREE_OBJECTID, DEFINE_NAME("csum") },
{ .id = BTRFS_QUOTA_TREE_OBJECTID, DEFINE_NAME("quota") },
{ .id = BTRFS_TREE_LOG_OBJECTID, DEFINE_NAME("log") },