Btrfs: Let some locks go during defrag and snapshot dropping

Signed-off-by: Chris Mason <chris.mason@oracle.com>

3 files changed, 14 insertions, 4 deletions

diff --git a/fs/btrfs/ctree.h b/fs/btrfs/ctree.h
index 42aa20301bc..8b7d01597f4 100644
--- a/fs/btrfs/ctree.h
+++ b/fs/btrfs/ctree.h
@@ -300,9 +300,9 @@ struct btrfs_fs_info {
         struct radix_tree_root block_group_data_radix;
         struct radix_tree_root extent_map_radix;
 
-        u64 extent_tree_insert[BTRFS_MAX_LEVEL * 3];
+        u64 extent_tree_insert[BTRFS_MAX_LEVEL * 6];
         int extent_tree_insert_nr;
-        u64 extent_tree_prealloc[BTRFS_MAX_LEVEL * 3];
+        u64 extent_tree_prealloc[BTRFS_MAX_LEVEL * 6];
         int extent_tree_prealloc_nr;
 
         u64 generation;
diff --git a/fs/btrfs/extent-tree.c b/fs/btrfs/extent-tree.c
index 26b8d340649..f7d76d34fc3 100644
--- a/fs/btrfs/extent-tree.c
+++ b/fs/btrfs/extent-tree.c
@@ -1018,7 +1018,7 @@ static int find_free_extent(struct btrfs_trans_handle *trans, struct btrfs_root
         if (num_blocks == 0) {
                 fill_prealloc = 1;
                 num_blocks = 1;
-                total_needed = (min(level + 1, BTRFS_MAX_LEVEL) + 2) * 3;
+                total_needed = (min(level + 1, BTRFS_MAX_LEVEL)) * 6;
         }
         if (fill_prealloc) {
                 u64 first;
@@ -1300,6 +1300,8 @@ int btrfs_alloc_extent(struct btrfs_trans_handle *trans,
                         ins->objectid;
                 ret = update_block_group(trans, root,
                                          ins->objectid, ins->offset, 1, 0, 0);
+                WARN_ON(info->extent_tree_insert_nr >
+                        ARRAY_SIZE(info->extent_tree_insert));
                 BUG_ON(ret);
                 return 0;
         }
@@ -1628,7 +1630,7 @@ int btrfs_drop_snapshot(struct btrfs_trans_handle *trans, struct btrfs_root
                 if (wret < 0)
                         ret = wret;
                 num_walks++;
-                if (num_walks > 10) {
+                if (num_walks > 2) {
                         ret = -EAGAIN;
                         get_bh(root->node);
                         break;
diff --git a/fs/btrfs/transaction.c b/fs/btrfs/transaction.c
index 338a7199363..88b0752550b 100644
--- a/fs/btrfs/transaction.c
+++ b/fs/btrfs/transaction.c
@@ -354,6 +354,7 @@ int btrfs_defrag_dirty_roots(struct btrfs_fs_info *info)
                                 mutex_unlock(&info->fs_mutex);
 
                                 btrfs_btree_balance_dirty(root);
+                                cond_resched();
 
                                 mutex_lock(&info->fs_mutex);
                                 trans = btrfs_start_transaction(tree_root, 1);
@@ -394,6 +395,12 @@ static int drop_dirty_roots(struct btrfs_root *tree_root,
                                 ret = err;
                         ret = btrfs_end_transaction(trans, tree_root);
                         BUG_ON(ret);
+                        mutex_unlock(&tree_root->fs_info->fs_mutex);
+
+                        btrfs_btree_balance_dirty(tree_root);
+                        schedule();
+
+                        mutex_lock(&tree_root->fs_info->fs_mutex);
                 }
                 BUG_ON(ret);
                 ret = btrfs_del_root(trans, tree_root, &dirty->root->root_key);
@@ -406,6 +413,7 @@ static int drop_dirty_roots(struct btrfs_root *tree_root,
                 kfree(dirty);
                 mutex_unlock(&tree_root->fs_info->fs_mutex);
                 btrfs_btree_balance_dirty(tree_root);
+                schedule();
         }
         return ret;
 }