diff mbox series

[v4,1/2] vhost: add packed ring support to vring base requests

Message ID 20181031102640.15377-2-maxime.coquelin@redhat.com (mailing list archive)
State Accepted, archived
Delegated to: Maxime Coquelin
Headers
Series vhost: packed ring support completion |

Checks

Context Check Description
ci/Intel-compilation success Compilation OK

Commit Message

Maxime Coquelin Oct. 31, 2018, 10:26 a.m. UTC 
  For packed ring layout, we need save avail index and its wrap
counter value. At restore time, the used index and its wrap counter
are set to available's ones, as the ring procressing is stopped
at vring base get time.

Signed-off-by: Maxime Coquelin <maxime.coquelin@redhat.com>
---
 lib/librte_vhost/vhost_user.c | 40 +++++++++++++++++++++++++++++------
 1 file changed, 34 insertions(+), 6 deletions(-)

Comments

Jens Freimann Nov. 2, 2018, 8:21 a.m. UTC | #1 
On Wed, Oct 31, 2018 at 11:26:39AM +0100, Maxime Coquelin wrote:
>For packed ring layout, we need save avail index and its wrap
>counter value. At restore time, the used index and its wrap counter
>are set to available's ones, as the ring procressing is stopped
>at vring base get time.
>
>Signed-off-by: Maxime Coquelin <maxime.coquelin@redhat.com>
>---
> lib/librte_vhost/vhost_user.c | 40 +++++++++++++++++++++++++++++------
> 1 file changed, 34 insertions(+), 6 deletions(-)
>

Reviewed-by: Jens Freimann <jfreimann@redhat.com>
diff mbox series

Patch

diff --git a/lib/librte_vhost/vhost_user.c b/lib/librte_vhost/vhost_user.c
index 508228a3c..cc154f312 100644
--- a/lib/librte_vhost/vhost_user.c
+++ b/lib/librte_vhost/vhost_user.c
@@ -696,10 +696,27 @@  vhost_user_set_vring_base(struct virtio_net **pdev,
 			int main_fd __rte_unused)
 {
 	struct virtio_net *dev = *pdev;
-	dev->virtqueue[msg->payload.state.index]->last_used_idx  =
-			msg->payload.state.num;
-	dev->virtqueue[msg->payload.state.index]->last_avail_idx =
-			msg->payload.state.num;
+	struct vhost_virtqueue *vq = dev->virtqueue[msg->payload.state.index];
+	uint64_t val = msg->payload.state.num;
+
+	if (vq_is_packed(dev)) {
+		/*
+		 * Bit[0:14]: avail index
+		 * Bit[15]: avail wrap counter
+		 */
+		vq->last_avail_idx = val & 0x7fff;
+		vq->avail_wrap_counter = !!(val & (0x1 << 15));
+		/*
+		 * Set used index to same value as available one, as
+		 * their values should be the same since ring processing
+		 * was stopped at get time.
+		 */
+		vq->last_used_idx = vq->last_avail_idx;
+		vq->used_wrap_counter = vq->avail_wrap_counter;
+	} else {
+		vq->last_used_idx = msg->payload.state.num;
+		vq->last_avail_idx = msg->payload.state.num;
+	}
 
 	return VH_RESULT_OK;
 }
@@ -1208,6 +1225,7 @@  vhost_user_get_vring_base(struct virtio_net **pdev,
 {
 	struct virtio_net *dev = *pdev;
 	struct vhost_virtqueue *vq = dev->virtqueue[msg->payload.state.index];
+	uint64_t val;
 
 	/* We have to stop the queue (virtio) if it is running. */
 	vhost_destroy_device_notify(dev);
@@ -1215,8 +1233,18 @@  vhost_user_get_vring_base(struct virtio_net **pdev,
 	dev->flags &= ~VIRTIO_DEV_READY;
 	dev->flags &= ~VIRTIO_DEV_VDPA_CONFIGURED;
 
-	/* Here we are safe to get the last avail index */
-	msg->payload.state.num = vq->last_avail_idx;
+	/* Here we are safe to get the indexes */
+	if (vq_is_packed(dev)) {
+		/*
+		 * Bit[0:14]: avail index
+		 * Bit[15]: avail wrap counter
+		 */
+		val = vq->last_avail_idx & 0x7fff;
+		val |= vq->avail_wrap_counter << 15;
+		msg->payload.state.num = val;
+	} else {
+		msg->payload.state.num = vq->last_avail_idx;
+	}
 
 	RTE_LOG(INFO, VHOST_CONFIG,
 		"vring base idx:%d file:%d\n", msg->payload.state.index,