diff options
| -rw-r--r-- | fs/btrfs/tree-log.c | 10 |
1 files changed, 8 insertions, 2 deletions
diff --git a/fs/btrfs/tree-log.c b/fs/btrfs/tree-log.c index 738f5d6beb95..2c7f9a5f8717 100644 --- a/fs/btrfs/tree-log.c +++ b/fs/btrfs/tree-log.c @@ -2961,8 +2961,11 @@ out_wake_log_root: mutex_unlock(&log_root_tree->log_mutex); /* - * The barrier before waitqueue_active is implied by mutex_unlock + * The barrier before waitqueue_active is needed so all the updates + * above are seen by the woken threads. It might not be necessary, but + * proving that seems to be hard. */ + smp_mb(); if (waitqueue_active(&log_root_tree->log_commit_wait[index2])) wake_up(&log_root_tree->log_commit_wait[index2]); out: @@ -2973,8 +2976,11 @@ out: mutex_unlock(&root->log_mutex); /* - * The barrier before waitqueue_active is implied by mutex_unlock + * The barrier before waitqueue_active is needed so all the updates + * above are seen by the woken threads. It might not be necessary, but + * proving that seems to be hard. */ + smp_mb(); if (waitqueue_active(&root->log_commit_wait[index1])) wake_up(&root->log_commit_wait[index1]); return ret; |