From 6209526531e70c080f79318ab8f50e26846c40a8 Mon Sep 17 00:00:00 2001 From: Fengguang Wu Date: Sat, 4 Aug 2012 01:45:02 -0600 Subject: btrfs: fix second lock in btrfs_delete_delayed_items() Fix a real bug caught by coccinelle. fs/btrfs/delayed-inode.c:1013:1-11: second lock on line 1013 Signed-off-by: Fengguang Wu --- fs/btrfs/delayed-inode.c | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-) (limited to 'fs/btrfs/delayed-inode.c') diff --git a/fs/btrfs/delayed-inode.c b/fs/btrfs/delayed-inode.c index 335605c8ceab..00deed4ef3ed 100644 --- a/fs/btrfs/delayed-inode.c +++ b/fs/btrfs/delayed-inode.c @@ -1028,9 +1028,10 @@ do_again: btrfs_release_delayed_item(prev); ret = 0; btrfs_release_path(path); - if (curr) + if (curr) { + mutex_unlock(&node->mutex); goto do_again; - else + } else goto delete_fail; } -- cgit v1.2.2 From 66657b318e0e443ada229fccd40c8be86cfebdbf Mon Sep 17 00:00:00 2001 From: Josef Bacik Date: Wed, 1 Aug 2012 15:36:24 -0400 Subject: Btrfs: barrier before waitqueue_active We need a barrir before calling waitqueue_active otherwise we will miss wakeups. So in places that do atomic_dec(); then atomic_read() use atomic_dec_return() which imply a memory barrier (see memory-barriers.txt) and then add an explicit memory barrier everywhere else that need them. Thanks, Signed-off-by: Josef Bacik --- fs/btrfs/delayed-inode.c | 7 +++---- 1 file changed, 3 insertions(+), 4 deletions(-) (limited to 'fs/btrfs/delayed-inode.c') diff --git a/fs/btrfs/delayed-inode.c b/fs/btrfs/delayed-inode.c index 00deed4ef3ed..07d5eeb1e6f1 100644 --- a/fs/btrfs/delayed-inode.c +++ b/fs/btrfs/delayed-inode.c @@ -512,8 +512,8 @@ static void __btrfs_remove_delayed_item(struct btrfs_delayed_item *delayed_item) rb_erase(&delayed_item->rb_node, root); delayed_item->delayed_node->count--; - atomic_dec(&delayed_root->items); - if (atomic_read(&delayed_root->items) < BTRFS_DELAYED_BACKGROUND && + if (atomic_dec_return(&delayed_root->items) < + BTRFS_DELAYED_BACKGROUND && waitqueue_active(&delayed_root->wait)) wake_up(&delayed_root->wait); } @@ -1056,8 +1056,7 @@ static void btrfs_release_delayed_inode(struct btrfs_delayed_node *delayed_node) delayed_node->count--; delayed_root = delayed_node->root->fs_info->delayed_root; - atomic_dec(&delayed_root->items); - if (atomic_read(&delayed_root->items) < + if (atomic_dec_return(&delayed_root->items) < BTRFS_DELAYED_BACKGROUND && waitqueue_active(&delayed_root->wait)) wake_up(&delayed_root->wait); -- cgit v1.2.2