From ea6a478ed9758cb0f5af228104b9434840aa20ff Mon Sep 17 00:00:00 2001 From: Josef Bacik Date: Thu, 20 Nov 2008 12:16:16 -0500 Subject: [PATCH] Btrfs: Fix for lockdep warnings with alloc_mutex and pinned_mutex This the lockdep complaint by having a different mutex to gaurd caching the block group, so you don't end up with this backwards dependancy. Thank you, Signed-off-by: Josef Bacik --- fs/btrfs/ctree.h | 1 + fs/btrfs/extent-tree.c | 32 ++++++++++++++++++-------------- 2 files changed, 19 insertions(+), 14 deletions(-) diff --git a/fs/btrfs/ctree.h b/fs/btrfs/ctree.h index 0f2a9b584fb6..166896dd44c2 100644 --- a/fs/btrfs/ctree.h +++ b/fs/btrfs/ctree.h @@ -580,6 +580,7 @@ struct btrfs_block_group_cache { struct btrfs_block_group_item item; spinlock_t lock; struct mutex alloc_mutex; + struct mutex cache_mutex; u64 pinned; u64 reserved; u64 flags; diff --git a/fs/btrfs/extent-tree.c b/fs/btrfs/extent-tree.c index b33e0bfb99e1..a970472eab17 100644 --- a/fs/btrfs/extent-tree.c +++ b/fs/btrfs/extent-tree.c @@ -170,8 +170,8 @@ static int add_new_free_space(struct btrfs_block_group_cache *block_group, start = extent_end + 1; } else if (extent_start > start && extent_start < end) { size = extent_start - start; - ret = btrfs_add_free_space_lock(block_group, start, - size); + ret = btrfs_add_free_space(block_group, start, + size); BUG_ON(ret); start = extent_end + 1; } else { @@ -181,7 +181,7 @@ static int add_new_free_space(struct btrfs_block_group_cache *block_group, if (start < end) { size = end - start; - ret = btrfs_add_free_space_lock(block_group, start, size); + ret = btrfs_add_free_space(block_group, start, size); BUG_ON(ret); } mutex_unlock(&info->pinned_mutex); @@ -2842,17 +2842,19 @@ static int noinline find_free_extent(struct btrfs_trans_handle *trans, if (!block_group) goto new_group_no_lock; + if (unlikely(!block_group->cached)) { + mutex_lock(&block_group->cache_mutex); + ret = cache_block_group(root, block_group); + mutex_unlock(&block_group->cache_mutex); + if (ret) + break; + } + mutex_lock(&block_group->alloc_mutex); if (unlikely(!block_group_bits(block_group, data))) goto new_group; - ret = cache_block_group(root, block_group); - if (ret) { - mutex_unlock(&block_group->alloc_mutex); - break; - } - - if (block_group->ro) + if (unlikely(block_group->ro)) goto new_group; free_space = btrfs_find_free_space(block_group, search_start, @@ -3273,12 +3275,12 @@ int btrfs_alloc_logged_extent(struct btrfs_trans_handle *trans, struct btrfs_block_group_cache *block_group; block_group = btrfs_lookup_block_group(root->fs_info, ins->objectid); - mutex_lock(&block_group->alloc_mutex); + mutex_lock(&block_group->cache_mutex); cache_block_group(root, block_group); + mutex_unlock(&block_group->cache_mutex); - ret = btrfs_remove_free_space_lock(block_group, ins->objectid, - ins->offset); - mutex_unlock(&block_group->alloc_mutex); + ret = btrfs_remove_free_space(block_group, ins->objectid, + ins->offset); BUG_ON(ret); ret = __btrfs_alloc_reserved_extent(trans, root, parent, root_objectid, ref_generation, owner, ins); @@ -5801,6 +5803,7 @@ int btrfs_read_block_groups(struct btrfs_root *root) spin_lock_init(&cache->lock); mutex_init(&cache->alloc_mutex); + mutex_init(&cache->cache_mutex); INIT_LIST_HEAD(&cache->list); read_extent_buffer(leaf, &cache->item, btrfs_item_ptr_offset(leaf, path->slots[0]), @@ -5854,6 +5857,7 @@ int btrfs_make_block_group(struct btrfs_trans_handle *trans, cache->key.offset = size; spin_lock_init(&cache->lock); mutex_init(&cache->alloc_mutex); + mutex_init(&cache->cache_mutex); INIT_LIST_HEAD(&cache->list); btrfs_set_key_type(&cache->key, BTRFS_BLOCK_GROUP_ITEM_KEY); -- 2.25.1