1 files changed, 47 insertions, 7 deletions

diff --git a/fs/btrfs/transaction.c b/fs/btrfs/transaction.c
index d638c54d39e9..f94c2ad8996c 100644
--- a/fs/btrfs/transaction.c
+++ b/fs/btrfs/transaction.c
@@ -65,6 +65,12 @@ static noinline int join_transaction(struct btrfs_root *root)
                 cur_trans->use_count = 1;
                 cur_trans->commit_done = 0;
                 cur_trans->start_time = get_seconds();
+
+                cur_trans->delayed_refs.root.rb_node = NULL;
+                cur_trans->delayed_refs.num_entries = 0;
+                cur_trans->delayed_refs.flushing = 0;
+                spin_lock_init(&cur_trans->delayed_refs.lock);
+
                 INIT_LIST_HEAD(&cur_trans->pending_snapshots);
                 list_add_tail(&cur_trans->list, &root->fs_info->trans_list);
                 extent_io_tree_init(&cur_trans->dirty_pages,
@@ -182,6 +188,7 @@ static struct btrfs_trans_handle *start_transaction(struct btrfs_root *root,
         h->block_group = 0;
         h->alloc_exclude_nr = 0;
         h->alloc_exclude_start = 0;
+        h->delayed_ref_updates = 0;
         root->fs_info->running_transaction->use_count++;
         mutex_unlock(&root->fs_info->trans_mutex);
         return h;
@@ -281,6 +288,14 @@ static int __btrfs_end_transaction(struct btrfs_trans_handle *trans,
         struct btrfs_transaction *cur_trans;
         struct btrfs_fs_info *info = root->fs_info;
 
+        if (trans->delayed_ref_updates &&
+            (trans->transaction->delayed_refs.flushing ||
+            trans->transaction->delayed_refs.num_entries > 16384)) {
+                btrfs_run_delayed_refs(trans, root, trans->delayed_ref_updates);
+        } else if (trans->transaction->delayed_refs.num_entries > 64) {
+                wake_up_process(root->fs_info->transaction_kthread);
+        }
+
         mutex_lock(&info->trans_mutex);
         cur_trans = info->running_transaction;
         WARN_ON(cur_trans != trans->transaction);
@@ -424,9 +439,10 @@ static int update_cowonly_root(struct btrfs_trans_handle *trans,
         u64 old_root_bytenr;
         struct btrfs_root *tree_root = root->fs_info->tree_root;
 
-        btrfs_extent_post_op(trans, root);
         btrfs_write_dirty_block_groups(trans, root);
-        btrfs_extent_post_op(trans, root);
+
+        ret = btrfs_run_delayed_refs(trans, root, (unsigned long)-1);
+        BUG_ON(ret);
 
         while (1) {
                 old_root_bytenr = btrfs_root_bytenr(&root->root_item);
@@ -438,14 +454,14 @@ static int update_cowonly_root(struct btrfs_trans_handle *trans,
                                      btrfs_header_level(root->node));
                 btrfs_set_root_generation(&root->root_item, trans->transid);
 
-                btrfs_extent_post_op(trans, root);
-
                 ret = btrfs_update_root(trans, tree_root,
                                         &root->root_key,
                                         &root->root_item);
                 BUG_ON(ret);
                 btrfs_write_dirty_block_groups(trans, root);
-                btrfs_extent_post_op(trans, root);
+
+                ret = btrfs_run_delayed_refs(trans, root, (unsigned long)-1);
+                BUG_ON(ret);
         }
         return 0;
 }
@@ -459,15 +475,18 @@ int btrfs_commit_tree_roots(struct btrfs_trans_handle *trans,
         struct btrfs_fs_info *fs_info = root->fs_info;
         struct list_head *next;
         struct extent_buffer *eb;
+        int ret;
 
-        btrfs_extent_post_op(trans, fs_info->tree_root);
+        ret = btrfs_run_delayed_refs(trans, root, (unsigned long)-1);
+        BUG_ON(ret);
 
         eb = btrfs_lock_root_node(fs_info->tree_root);
         btrfs_cow_block(trans, fs_info->tree_root, eb, NULL, 0, &eb);
         btrfs_tree_unlock(eb);
         free_extent_buffer(eb);
 
-        btrfs_extent_post_op(trans, fs_info->tree_root);
+        ret = btrfs_run_delayed_refs(trans, root, (unsigned long)-1);
+        BUG_ON(ret);
 
         while (!list_empty(&fs_info->dirty_cowonly_roots)) {
                 next = fs_info->dirty_cowonly_roots.next;
@@ -475,6 +494,9 @@ int btrfs_commit_tree_roots(struct btrfs_trans_handle *trans,
                 root = list_entry(next, struct btrfs_root, dirty_list);
 
                 update_cowonly_root(trans, root);
+
+                ret = btrfs_run_delayed_refs(trans, root, (unsigned long)-1);
+                BUG_ON(ret);
         }
         return 0;
 }
@@ -895,6 +917,21 @@ int btrfs_commit_transaction(struct btrfs_trans_handle *trans,
         DEFINE_WAIT(wait);
         int ret;
 
+        /* make a pass through all the delayed refs we have so far
+         * any runnings procs may add more while we are here
+         */
+        ret = btrfs_run_delayed_refs(trans, root, 0);
+        BUG_ON(ret);
+
+        /*
+         * set the flushing flag so procs in this transaction have to
+         * start sending their work down.
+         */
+        trans->transaction->delayed_refs.flushing = 1;
+
+        ret = btrfs_run_delayed_refs(trans, root, (u64)-1);
+        BUG_ON(ret);
+
         INIT_LIST_HEAD(&dirty_fs_roots);
         mutex_lock(&root->fs_info->trans_mutex);
         if (trans->transaction->in_commit) {
@@ -969,6 +1006,9 @@ int btrfs_commit_transaction(struct btrfs_trans_handle *trans,
         ret = create_pending_snapshots(trans, root->fs_info);
         BUG_ON(ret);
 
+        ret = btrfs_run_delayed_refs(trans, root, (unsigned long)-1);
+        BUG_ON(ret);
+
         WARN_ON(cur_trans != trans->transaction);
 
         /* btrfs_commit_tree_roots is responsible for getting the