diff options
Diffstat (limited to 'fs/btrfs/extent-tree.c')
| -rw-r--r-- | fs/btrfs/extent-tree.c | 19 |
1 files changed, 17 insertions, 2 deletions
diff --git a/fs/btrfs/extent-tree.c b/fs/btrfs/extent-tree.c index c4661db2b72a..e6993f687953 100644 --- a/fs/btrfs/extent-tree.c +++ b/fs/btrfs/extent-tree.c @@ -3684,11 +3684,21 @@ int btrfs_write_dirty_block_groups(struct btrfs_trans_handle *trans, return -ENOMEM; /* - * We don't need the lock here since we are protected by the transaction - * commit. We want to do the cache_save_setup first and then run the + * Even though we are in the critical section of the transaction commit, + * we can still have concurrent tasks adding elements to this + * transaction's list of dirty block groups. These tasks correspond to + * endio free space workers started when writeback finishes for a + * space cache, which run inode.c:btrfs_finish_ordered_io(), and can + * allocate new block groups as a result of COWing nodes of the root + * tree when updating the free space inode. The writeback for the space + * caches is triggered by an earlier call to + * btrfs_start_dirty_block_groups() and iterations of the following + * loop. + * Also we want to do the cache_save_setup first and then run the * delayed refs to make sure we have the best chance at doing this all * in one shot. */ + spin_lock(&cur_trans->dirty_bgs_lock); while (!list_empty(&cur_trans->dirty_bgs)) { cache = list_first_entry(&cur_trans->dirty_bgs, struct btrfs_block_group_cache, @@ -3700,11 +3710,13 @@ int btrfs_write_dirty_block_groups(struct btrfs_trans_handle *trans, * finish and then do it all again */ if (!list_empty(&cache->io_list)) { + spin_unlock(&cur_trans->dirty_bgs_lock); list_del_init(&cache->io_list); btrfs_wait_cache_io(root, trans, cache, &cache->io_ctl, path, cache->key.objectid); btrfs_put_block_group(cache); + spin_lock(&cur_trans->dirty_bgs_lock); } /* @@ -3712,6 +3724,7 @@ int btrfs_write_dirty_block_groups(struct btrfs_trans_handle *trans, * on any pending IO */ list_del_init(&cache->dirty_list); + spin_unlock(&cur_trans->dirty_bgs_lock); should_put = 1; cache_save_setup(cache, trans, path); @@ -3743,7 +3756,9 @@ int btrfs_write_dirty_block_groups(struct btrfs_trans_handle *trans, /* if its not on the io list, we need to put the block group */ if (should_put) btrfs_put_block_group(cache); + spin_lock(&cur_trans->dirty_bgs_lock); } + spin_unlock(&cur_trans->dirty_bgs_lock); while (!list_empty(io)) { cache = list_first_entry(io, struct btrfs_block_group_cache, |
