diff options
| -rw-r--r-- | module/zfs/vdev_queue.c | 22 |
1 files changed, 12 insertions, 10 deletions
diff --git a/module/zfs/vdev_queue.c b/module/zfs/vdev_queue.c index e74df76b7..86b20f134 100644 --- a/module/zfs/vdev_queue.c +++ b/module/zfs/vdev_queue.c @@ -709,6 +709,18 @@ vdev_queue_aggregate(vdev_queue_t *vq, zio_t *zio) do { dio = nio; nio = AVL_NEXT(t, dio); + zio_add_child(dio, aio); + vdev_queue_io_remove(vq, dio); + } while (dio != last); + + /* + * We need to drop the vdev queue's lock during zio_execute() to + * avoid a deadlock that we could encounter due to lock order + * reversal between vq_lock and io_lock in zio_change_priority(). + * Use the dropped lock to do memory copy without congestion. + */ + mutex_exit(&vq->vq_lock); + while ((dio = zio_walk_parents(aio, &zl)) != NULL) { ASSERT3U(dio->io_type, ==, aio->io_type); if (dio->io_flags & ZIO_FLAG_NODATA) { @@ -720,16 +732,6 @@ vdev_queue_aggregate(vdev_queue_t *vq, zio_t *zio) dio->io_offset - aio->io_offset, 0, dio->io_size); } - zio_add_child(dio, aio); - vdev_queue_io_remove(vq, dio); - } while (dio != last); - - /* - * We need to drop the vdev queue's lock to avoid a deadlock that we - * could encounter since this I/O will complete immediately. - */ - mutex_exit(&vq->vq_lock); - while ((dio = zio_walk_parents(aio, &zl)) != NULL) { zio_vdev_io_bypass(dio); zio_execute(dio); } |