[dpdk-dev] [PATCH v4 0/2] vhost: packed ring support completion

[dpdk-dev] [PATCH v4 0/2] vhost: packed ring support completion

[Maxime Coquelin]

In this v4, it restores back to only save last avail index and
its wrap counter value at get time, and restore both used
and avail indexes to avail values at set time.
The change compared to v1 is that wrap counter value is
saved into bit 15, so that it is consistent with the event
suppression structure format.

Initial series ading packed ring layout support to the
vhost library was missing the save and restore of the
wrap counters and indexs on vring base requests used for
migration.

First patch saves/restores the used and avail indexes and their
wrap counters values into/from the vring state num field.

Maxime Coquelin (2):
  vhost: add packed ring support to vring base requests
  vhost: advertize packed ring layout support

 lib/librte_vhost/vhost.h      |  3 ++-
 lib/librte_vhost/vhost_user.c | 40 +++++++++++++++++++++++++++++------
 2 files changed, 36 insertions(+), 7 deletions(-)

-- 
2.17.2

[dpdk-dev] [PATCH v4 1/2] vhost: add packed ring support to vring base requests

[Maxime Coquelin]

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(-)

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,
-- 
2.17.2

Re: [dpdk-dev] [PATCH v4 1/2] vhost: add packed ring support to vring base requests

[Jens Freimann]

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>

[dpdk-dev] [PATCH v4 2/2] vhost: advertize packed ring layout support

[Maxime Coquelin]

Signed-off-by: Maxime Coquelin <maxime.coquelin@redhat.com>
---
 lib/librte_vhost/vhost.h | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/lib/librte_vhost/vhost.h b/lib/librte_vhost/vhost.h
index b4abad30c..760f42192 100644
--- a/lib/librte_vhost/vhost.h
+++ b/lib/librte_vhost/vhost.h
@@ -275,7 +275,8 @@ struct vring_packed_desc_event {
 				(1ULL << VIRTIO_RING_F_EVENT_IDX) | \
 				(1ULL << VIRTIO_NET_F_MTU)  | \
 				(1ULL << VIRTIO_F_IN_ORDER) | \
-				(1ULL << VIRTIO_F_IOMMU_PLATFORM))
+				(1ULL << VIRTIO_F_IOMMU_PLATFORM) | \
+				(1ULL << VIRTIO_F_RING_PACKED))
 
 
 struct guest_page {
-- 
2.17.2

Re: [dpdk-dev] [PATCH v4 2/2] vhost: advertize packed ring layout support

[Jens Freimann]

On Wed, Oct 31, 2018 at 11:26:40AM +0100, Maxime Coquelin wrote:
>Signed-off-by: Maxime Coquelin <maxime.coquelin@redhat.com>
>---
> lib/librte_vhost/vhost.h | 3 ++-
> 1 file changed, 2 insertions(+), 1 deletion(-)
>

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

Re: [dpdk-dev] [PATCH v4 0/2] vhost: packed ring support completion

[Tiwei Bie]

On Wed, Oct 31, 2018 at 11:26:38AM +0100, Maxime Coquelin wrote:
> In this v4, it restores back to only save last avail index and
> its wrap counter value at get time, and restore both used
> and avail indexes to avail values at set time.
> The change compared to v1 is that wrap counter value is
> saved into bit 15, so that it is consistent with the event
> suppression structure format.
> 
> Initial series ading packed ring layout support to the
> vhost library was missing the save and restore of the
> wrap counters and indexs on vring base requests used for
> migration.
> 
> First patch saves/restores the used and avail indexes and their
> wrap counters values into/from the vring state num field.
> 
> Maxime Coquelin (2):
>   vhost: add packed ring support to vring base requests
>   vhost: advertize packed ring layout support
> 
>  lib/librte_vhost/vhost.h      |  3 ++-
>  lib/librte_vhost/vhost_user.c | 40 +++++++++++++++++++++++++++++------
>  2 files changed, 36 insertions(+), 7 deletions(-)
> 
> -- 
> 2.17.2
> 

Reviewed-by: Tiwei Bie <tiwei.bie@intel.com>

Thanks!

Re: [dpdk-dev] [PATCH v4 0/2] vhost: packed ring support completion

[Maxime Coquelin]

On 11/2/18 2:42 PM, Tiwei Bie wrote:
> On Wed, Oct 31, 2018 at 11:26:38AM +0100, Maxime Coquelin wrote:
>> In this v4, it restores back to only save last avail index and
>> its wrap counter value at get time, and restore both used
>> and avail indexes to avail values at set time.
>> The change compared to v1 is that wrap counter value is
>> saved into bit 15, so that it is consistent with the event
>> suppression structure format.
>>
>> Initial series ading packed ring layout support to the
>> vhost library was missing the save and restore of the
>> wrap counters and indexs on vring base requests used for
>> migration.
>>
>> First patch saves/restores the used and avail indexes and their
>> wrap counters values into/from the vring state num field.
>>
>> Maxime Coquelin (2):
>>    vhost: add packed ring support to vring base requests
>>    vhost: advertize packed ring layout support
>>
>>   lib/librte_vhost/vhost.h      |  3 ++-
>>   lib/librte_vhost/vhost_user.c | 40 +++++++++++++++++++++++++++++------
>>   2 files changed, 36 insertions(+), 7 deletions(-)
>>
>> -- 
>> 2.17.2
>>
> 
> Reviewed-by: Tiwei Bie <tiwei.bie@intel.com>
> 
> Thanks!
> 

Applied to dpdk-next-virtio/master

Maxime