btrfs: make load_block_group_size_class() return void

There's no point in returning anything since determining and setting a
size class for a block group is an optimization, not something critical.
The only caller of load_block_group_size_class() (the caching thread)
does not do anything with the return value anyway, exactly because having
a size class is just an optimization and it can always be set later when
adding reserved bytes to a block group (btrfs_add_reserved_bytes()).

Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Reviewed-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>

diff --git a/fs/btrfs/block-group.c b/fs/btrfs/block-group.c
index 022c77f8d0e2db2a0fba23f56293977062f74697..20dd4a3d9961ccde3de5e3a4d7131c174fd5ba89 100644 (file)
--- a/fs/btrfs/block-group.c
+++ b/fs/btrfs/block-group.c
@@ -673,27 +673,29 @@ static int sample_block_group_extent_item(struct btrfs_caching_control *caching_
  * 3, we can either read every file extent, or admit that this is best effort
  * anyway and try to stay fast.
  *
- * Returns: 0 on success, negative error code on error.
+ * No errors are returned since failing to determine the size class is not a
+ * critical error, size classes are just an optimization.
  */
-static int load_block_group_size_class(struct btrfs_caching_control *caching_ctl,
-                                      struct btrfs_block_group *block_group)
+static void load_block_group_size_class(struct btrfs_caching_control *caching_ctl,
+                                       struct btrfs_block_group *block_group)
 {
        struct btrfs_fs_info *fs_info = block_group->fs_info;
        struct btrfs_key key;
        int i;
        u64 min_size = block_group->length;
        enum btrfs_block_group_size_class size_class = BTRFS_BG_SZ_NONE;
-       int ret;
 
        if (!btrfs_block_group_should_use_size_class(block_group))
-               return 0;
+               return;
 
        lockdep_assert_held(&caching_ctl->mutex);
        lockdep_assert_held_read(&fs_info->commit_root_sem);
        for (i = 0; i < 5; ++i) {
+               int ret;
+
                ret = sample_block_group_extent_item(caching_ctl, block_group, i, 5, &key);
                if (ret < 0)
-                       goto out;
+                       return;
                if (ret > 0)
                        continue;
                min_size = min_t(u64, min_size, key.offset);
@@ -704,8 +706,6 @@ static int load_block_group_size_class(struct btrfs_caching_control *caching_ctl
                block_group->size_class = size_class;
                spin_unlock(&block_group->lock);
        }
-out:
-       return ret;
 }
 
 static int load_extent_tree_free(struct btrfs_caching_control *caching_ctl)