Coalesce multiple map or unmap operations to just one
so that all mapping setup or teardown can occur in a
single DMA batch.

Signed-off-by: Si-Wei Liu <si-wei.liu@oracle.com>
---
 hw/virtio/vhost-vdpa.c | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/hw/virtio/vhost-vdpa.c b/hw/virtio/vhost-vdpa.c
index 68dc01b..d98704a 100644
--- a/hw/virtio/vhost-vdpa.c
+++ b/hw/virtio/vhost-vdpa.c
@@ -1288,6 +1288,7 @@ static bool vhost_vdpa_svqs_start(struct vhost_dev *dev)
         return true;
     }
 
+    vhost_vdpa_dma_batch_begin_once(v->shared, v->address_space_id);
     for (i = 0; i < v->shadow_vqs->len; ++i) {
         VirtQueue *vq = virtio_get_queue(dev->vdev, dev->vq_index + i);
         VhostShadowVirtqueue *svq = g_ptr_array_index(v->shadow_vqs, i);
@@ -1315,6 +1316,7 @@ static bool vhost_vdpa_svqs_start(struct vhost_dev *dev)
             goto err_set_addr;
         }
     }
+    vhost_vdpa_dma_batch_end_once(v->shared, v->address_space_id);
 
     return true;
 
@@ -1323,6 +1325,7 @@ err_set_addr:
 
 err_map:
     vhost_svq_stop(g_ptr_array_index(v->shadow_vqs, i));
+    vhost_vdpa_dma_batch_end_once(v->shared, v->address_space_id);
 
 err:
     error_reportf_err(err, "Cannot setup SVQ %u: ", i);
@@ -1343,6 +1346,7 @@ static void vhost_vdpa_svqs_stop(struct vhost_dev *dev)
         return;
     }
 
+    vhost_vdpa_dma_batch_begin_once(v->shared, v->address_space_id);
     for (unsigned i = 0; i < v->shadow_vqs->len; ++i) {
         VhostShadowVirtqueue *svq = g_ptr_array_index(v->shadow_vqs, i);
 
@@ -1352,6 +1356,7 @@ static void vhost_vdpa_svqs_stop(struct vhost_dev *dev)
         event_notifier_cleanup(&svq->hdev_kick);
         event_notifier_cleanup(&svq->hdev_call);
     }
+    vhost_vdpa_dma_batch_end_once(v->shared, v->address_space_id);
 }
 
 static void vhost_vdpa_suspend(struct vhost_dev *dev)
-- 
1.8.3.1

On Fri, Dec 8, 2023 at 2:51 AM Si-Wei Liu <si-wei.liu@oracle.com> wrote:
>
> Coalesce multiple map or unmap operations to just one
> so that all mapping setup or teardown can occur in a
> single DMA batch.
>
> Signed-off-by: Si-Wei Liu <si-wei.liu@oracle.com>

Acked-by: Jason Wang <jasowang@redhat.com>

Thanks