From 1e5063d093b5f024ae35bf835ca07463de2c1a1f Mon Sep 17 00:00:00 2001 From: Mark Fasheh Date: Tue, 12 Jul 2011 10:46:06 -0700 Subject: btrfs: Don't BUG_ON alloc_path errors in replay_one_buffer() The two ->process_func call sites in tree-log.c which were ignoring a return code have also been updated to gracefully exit as well. Signed-off-by: Mark Fasheh --- fs/btrfs/tree-log.c | 12 +++++++++--- 1 file changed, 9 insertions(+), 3 deletions(-) (limited to 'fs/btrfs/tree-log.c') diff --git a/fs/btrfs/tree-log.c b/fs/btrfs/tree-log.c index 4ce8a9f41d1e..f3cacc079102 100644 --- a/fs/btrfs/tree-log.c +++ b/fs/btrfs/tree-log.c @@ -1617,7 +1617,8 @@ static int replay_one_buffer(struct btrfs_root *log, struct extent_buffer *eb, return 0; path = btrfs_alloc_path(); - BUG_ON(!path); + if (!path) + return -ENOMEM; nritems = btrfs_header_nritems(eb); for (i = 0; i < nritems; i++) { @@ -1723,7 +1724,9 @@ static noinline int walk_down_log_tree(struct btrfs_trans_handle *trans, return -ENOMEM; if (*level == 1) { - wc->process_func(root, next, wc, ptr_gen); + ret = wc->process_func(root, next, wc, ptr_gen); + if (ret) + return ret; path->slots[*level]++; if (wc->free) { @@ -1788,8 +1791,11 @@ static noinline int walk_up_log_tree(struct btrfs_trans_handle *trans, parent = path->nodes[*level + 1]; root_owner = btrfs_header_owner(parent); - wc->process_func(root, path->nodes[*level], wc, + ret = wc->process_func(root, path->nodes[*level], wc, btrfs_header_generation(path->nodes[*level])); + if (ret) + return ret; + if (wc->free) { struct extent_buffer *next; -- cgit v1.2.3 From bd681513fa6f2ff29aa391f01e413a2d1c59fd77 Mon Sep 17 00:00:00 2001 From: Chris Mason Date: Sat, 16 Jul 2011 15:23:14 -0400 Subject: Btrfs: switch the btrfs tree locks to reader/writer The btrfs metadata btree is the source of significant lock contention, especially in the root node. This commit changes our locking to use a reader/writer lock. The lock is built on top of rw spinlocks, and it extends the lock tracking to remember if we have a read lock or a write lock when we go to blocking. Atomics count the number of blocking readers or writers at any given time. It removes all of the adaptive spinning from the old code and uses only the spinning/blocking hints inside of btrfs to decide when it should continue spinning. In read heavy workloads this is dramatically faster. In write heavy workloads we're still faster because of less contention on the root node lock. We suffer slightly in dbench because we schedule more often during write locks, but all other benchmarks so far are improved. Signed-off-by: Chris Mason --- fs/btrfs/tree-log.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) (limited to 'fs/btrfs/tree-log.c') diff --git a/fs/btrfs/tree-log.c b/fs/btrfs/tree-log.c index 4ce8a9f41d1e..ac278dd83175 100644 --- a/fs/btrfs/tree-log.c +++ b/fs/btrfs/tree-log.c @@ -1730,8 +1730,8 @@ static noinline int walk_down_log_tree(struct btrfs_trans_handle *trans, btrfs_read_buffer(next, ptr_gen); btrfs_tree_lock(next); - clean_tree_block(trans, root, next); btrfs_set_lock_blocking(next); + clean_tree_block(trans, root, next); btrfs_wait_tree_block_writeback(next); btrfs_tree_unlock(next); @@ -1796,8 +1796,8 @@ static noinline int walk_up_log_tree(struct btrfs_trans_handle *trans, next = path->nodes[*level]; btrfs_tree_lock(next); - clean_tree_block(trans, root, next); btrfs_set_lock_blocking(next); + clean_tree_block(trans, root, next); btrfs_wait_tree_block_writeback(next); btrfs_tree_unlock(next); @@ -1864,8 +1864,8 @@ static int walk_log_tree(struct btrfs_trans_handle *trans, next = path->nodes[orig_level]; btrfs_tree_lock(next); - clean_tree_block(trans, log, next); btrfs_set_lock_blocking(next); + clean_tree_block(trans, log, next); btrfs_wait_tree_block_writeback(next); btrfs_tree_unlock(next); -- cgit v1.2.3