diff options
| -rw-r--r-- | fs/btrfs/delayed-inode.c | 4 | ||||
| -rw-r--r-- | fs/btrfs/disk-io.c | 3 | ||||
| -rw-r--r-- | fs/btrfs/inode.c | 3 | ||||
| -rw-r--r-- | fs/btrfs/locking.c | 9 | ||||
| -rw-r--r-- | fs/btrfs/volumes.c | 3 |
5 files changed, 22 insertions, 0 deletions
diff --git a/fs/btrfs/delayed-inode.c b/fs/btrfs/delayed-inode.c index a2ae42720a6a..e0941fbb913c 100644 --- a/fs/btrfs/delayed-inode.c +++ b/fs/btrfs/delayed-inode.c @@ -463,6 +463,10 @@ static int __btrfs_add_delayed_deletion_item(struct btrfs_delayed_node *node, static void finish_one_item(struct btrfs_delayed_root *delayed_root) { int seq = atomic_inc_return(&delayed_root->items_seq); + + /* + * atomic_dec_return implies a barrier for waitqueue_active + */ if ((atomic_dec_return(&delayed_root->items) < BTRFS_DELAYED_BACKGROUND || seq % BTRFS_DELAYED_BATCH == 0) && waitqueue_active(&delayed_root->wait)) diff --git a/fs/btrfs/disk-io.c b/fs/btrfs/disk-io.c index 295795aebe0b..379526ffd84d 100644 --- a/fs/btrfs/disk-io.c +++ b/fs/btrfs/disk-io.c @@ -802,6 +802,9 @@ static void run_one_async_done(struct btrfs_work *work) limit = btrfs_async_submit_limit(fs_info); limit = limit * 2 / 3; + /* + * atomic_dec_return implies a barrier for waitqueue_active + */ if (atomic_dec_return(&fs_info->nr_async_submits) < limit && waitqueue_active(&fs_info->async_submit_wait)) wake_up(&fs_info->async_submit_wait); diff --git a/fs/btrfs/inode.c b/fs/btrfs/inode.c index 611b66d73e80..7be4abe25e06 100644 --- a/fs/btrfs/inode.c +++ b/fs/btrfs/inode.c @@ -1096,6 +1096,9 @@ static noinline void async_cow_submit(struct btrfs_work *work) nr_pages = (async_cow->end - async_cow->start + PAGE_CACHE_SIZE) >> PAGE_CACHE_SHIFT; + /* + * atomic_sub_return implies a barrier for waitqueue_active + */ if (atomic_sub_return(nr_pages, &root->fs_info->async_delalloc_pages) < 5 * 1024 * 1024 && waitqueue_active(&root->fs_info->async_submit_wait)) diff --git a/fs/btrfs/locking.c b/fs/btrfs/locking.c index 03f8630dbaf2..8077461fc56a 100644 --- a/fs/btrfs/locking.c +++ b/fs/btrfs/locking.c @@ -79,6 +79,9 @@ void btrfs_clear_lock_blocking_rw(struct extent_buffer *eb, int rw) write_lock(&eb->lock); WARN_ON(atomic_read(&eb->spinning_writers)); atomic_inc(&eb->spinning_writers); + /* + * atomic_dec_and_test implies a barrier for waitqueue_active + */ if (atomic_dec_and_test(&eb->blocking_writers) && waitqueue_active(&eb->write_lock_wq)) wake_up(&eb->write_lock_wq); @@ -86,6 +89,9 @@ void btrfs_clear_lock_blocking_rw(struct extent_buffer *eb, int rw) BUG_ON(atomic_read(&eb->blocking_readers) == 0); read_lock(&eb->lock); atomic_inc(&eb->spinning_readers); + /* + * atomic_dec_and_test implies a barrier for waitqueue_active + */ if (atomic_dec_and_test(&eb->blocking_readers) && waitqueue_active(&eb->read_lock_wq)) wake_up(&eb->read_lock_wq); @@ -229,6 +235,9 @@ void btrfs_tree_read_unlock_blocking(struct extent_buffer *eb) } btrfs_assert_tree_read_locked(eb); WARN_ON(atomic_read(&eb->blocking_readers) == 0); + /* + * atomic_dec_and_test implies a barrier for waitqueue_active + */ if (atomic_dec_and_test(&eb->blocking_readers) && waitqueue_active(&eb->read_lock_wq)) wake_up(&eb->read_lock_wq); diff --git a/fs/btrfs/volumes.c b/fs/btrfs/volumes.c index 6fc735869c18..ff3527192409 100644 --- a/fs/btrfs/volumes.c +++ b/fs/btrfs/volumes.c @@ -345,6 +345,9 @@ loop_lock: pending = pending->bi_next; cur->bi_next = NULL; + /* + * atomic_dec_return implies a barrier for waitqueue_active + */ if (atomic_dec_return(&fs_info->nr_async_bios) < limit && waitqueue_active(&fs_info->async_submit_wait)) wake_up(&fs_info->async_submit_wait); |