[V5,2/2] btrfs: implement delayed inode items operation

Commit Message

Itaru Kitayama March 27, 2011, 5:30 a.m. UTC

None

Patch

diff --git a/fs/btrfs/ctree.h b/fs/btrfs/ctree.h
index 2164296..f40ff4e 100644
--- a/fs/btrfs/ctree.h
+++ b/fs/btrfs/ctree.h
@@ -740,6 +740,7 @@  struct btrfs_space_info {
 	struct list_head block_groups[BTRFS_NR_RAID_TYPES];
 	spinlock_t lock;
 	struct rw_semaphore groups_sem;
+	struct srcu_struct groups_srcu;
 	atomic_t caching_threads;
 };
 
diff --git a/fs/btrfs/extent-tree.c b/fs/btrfs/extent-tree.c
index 9e4c9f4..22d6dbb 100644
--- a/fs/btrfs/extent-tree.c
+++ b/fs/btrfs/extent-tree.c
@@ -3003,6 +3003,7 @@  static int update_space_info(struct btrfs_fs_info *info, u64 flags,
 	for (i = 0; i < BTRFS_NR_RAID_TYPES; i++)
 		INIT_LIST_HEAD(&found->block_groups[i]);
 	init_rwsem(&found->groups_sem);
+	init_srcu_struct(&found->groups_srcu);
 	spin_lock_init(&found->lock);
 	found->flags = flags & (BTRFS_BLOCK_GROUP_DATA |
 				BTRFS_BLOCK_GROUP_SYSTEM |
@@ -4853,6 +4854,7 @@  static noinline int find_free_extent(struct btrfs_trans_handle *trans,
 				     int data)
 {
 	int ret = 0;
+	int idx;
 	struct btrfs_root *root = orig_root->fs_info->extent_root;
 	struct btrfs_free_cluster *last_ptr = NULL;
 	struct btrfs_block_group_cache *block_group = NULL;
@@ -4929,7 +4931,7 @@  ideal_cache:
 		if (block_group && block_group_bits(block_group, data) &&
 		    (block_group->cached != BTRFS_CACHE_NO ||
 		     search_start == ideal_cache_offset)) {
-			down_read(&space_info->groups_sem);
+			idx = srcu_read_lock(&space_info->groups_srcu);
 			if (list_empty(&block_group->list) ||
 			    block_group->ro) {
 				/*
@@ -4939,7 +4941,7 @@  ideal_cache:
 				 * valid
 				 */
 				btrfs_put_block_group(block_group);
-				up_read(&space_info->groups_sem);
+				srcu_read_unlock(&space_info->groups_srcu, idx);
 			} else {
 				index = get_block_group_index(block_group);
 				goto have_block_group;
@@ -4949,8 +4951,8 @@  ideal_cache:
 		}
 	}
 search:
-	down_read(&space_info->groups_sem);
-	list_for_each_entry(block_group, &space_info->block_groups[index],
+	idx = srcu_read_lock(&space_info->groups_srcu);
+	list_for_each_entry_rcu(block_group, &space_info->block_groups[index],
 			    list) {
 		u64 offset;
 		int cached;
@@ -5197,8 +5199,8 @@  loop:
 		BUG_ON(index != get_block_group_index(block_group));
 		btrfs_put_block_group(block_group);
 	}
-	up_read(&space_info->groups_sem);
-
+	srcu_read_unlock(&space_info->groups_srcu, idx);
+	
 	if (!ins->objectid && ++index < BTRFS_NR_RAID_TYPES)
 		goto search;