Commit 39276ee8 authored by Jin Yu's avatar Jin Yu Committed by Changpeng Liu
Browse files

vhost: negotiate the packed ring feature 



Add the packed ring support in spdk vhost.
Negotiate packed ring feature when start device.

Change-Id: Idef50a1426b6e38d789d8c6982a3ed7594e32cf5
Signed-off-by: default avatarJin Yu <jin.yu@intel.com>
Reviewed-on: https://review.spdk.io/gerrit/c/spdk/spdk/+/672


Tested-by: default avatarSPDK CI Jenkins <sys_sgci@intel.com>
Reviewed-by: default avatarShuhei Matsumoto <shuhei.matsumoto.xt@hitachi.com>
Reviewed-by: default avatarBen Walker <benjamin.walker@intel.com>
Reviewed-by: default avatarChangpeng Liu <changpeng.liu@intel.com>
parent 4d2e26d8

lib/vhost/vhost.c

+46 −7
Original line number Diff line number Diff line
@@ -880,9 +880,24 @@ _stop_session(struct spdk_vhost_session *vsession) 


	for (i = 0; i < vsession->max_queues; i++) {

		q = &vsession->virtqueue[i];



		/* vring.desc and vring.desc_packed are in a union struct

		 * so q->vring.desc can replace q->vring.desc_packed.

		 */

		if (q->vring.desc == NULL) {

			continue;

		}



		/* Packed virtqueues support up to 2^15 entries each

		 * so left one bit can be used as wrap counter.

		 */

		if (q->packed.packed_ring) {

			q->last_avail_idx = q->last_avail_idx |

					    ((uint16_t)q->packed.avail_phase << 15);

			q->last_used_idx = q->last_used_idx |

					   ((uint16_t)q->packed.used_phase << 15);

		}



		rte_vhost_set_vring_base(vsession->vid, i, q->last_avail_idx, q->last_used_idx);

	}
@@ -925,6 +940,7 @@ vhost_start_device_cb(int vid) 
	struct spdk_vhost_session *vsession;

	int rc = -1;

	uint16_t i;

	bool packed_ring;



	pthread_mutex_lock(&g_vhost_mutex);
@@ -941,6 +957,13 @@ vhost_start_device_cb(int vid) 
		goto out;

	}



	if (vhost_get_negotiated_features(vid, &vsession->negotiated_features) != 0) {

		SPDK_ERRLOG("vhost device %d: Failed to get negotiated driver features\n", vid);

		goto out;

	}



	packed_ring = ((vsession->negotiated_features & (1ULL << VIRTIO_F_RING_PACKED)) != 0);



	vsession->max_queues = 0;

	memset(vsession->virtqueue, 0, sizeof(vsession->virtqueue));

	for (i = 0; i < SPDK_VHOST_MAX_VQUEUES; i++) {
@@ -953,6 +976,9 @@ vhost_start_device_cb(int vid) 
		q->vring_idx = i;

		rte_vhost_get_vhost_ring_inflight(vid, i, &q->vring_inflight);



		/* vring.desc and vring.desc_packed are in a union struct

		 * so q->vring.desc can replace q->vring.desc_packed.

		 */

		if (q->vring.desc == NULL || q->vring.size == 0) {

			continue;

		}
@@ -962,14 +988,24 @@ vhost_start_device_cb(int vid) 
			continue;

		}



		if (packed_ring) {

			/* Packed virtqueues support up to 2^15 entries each

			 * so left one bit can be used as wrap counter.

			 */

			q->packed.avail_phase = q->last_avail_idx >> 15;

			q->last_avail_idx = q->last_avail_idx & 0x7FFF;

			q->packed.used_phase = q->last_used_idx >> 15;

			q->last_used_idx = q->last_used_idx & 0x7FFF;



			/* Disable I/O submission notifications, we'll be polling. */

			q->vring.device_event->flags = VRING_PACKED_EVENT_FLAG_DISABLE;

		} else {

			/* Disable I/O submission notifications, we'll be polling. */

			q->vring.used->flags = VRING_USED_F_NO_NOTIFY;

		vsession->max_queues = i + 1;

		}



	if (vhost_get_negotiated_features(vid, &vsession->negotiated_features) != 0) {

		SPDK_ERRLOG("vhost device %d: Failed to get negotiated driver features\n", vid);

		goto out;

		q->packed.packed_ring = packed_ring;

		vsession->max_queues = i + 1;

	}



	if (vhost_get_mem_table(vid, &vsession->mem) != 0) {
@@ -989,6 +1025,9 @@ vhost_start_device_cb(int vid) 
	for (i = 0; i < vsession->max_queues; i++) {

		struct spdk_vhost_virtqueue *q = &vsession->virtqueue[i];



		/* vring.desc and vring.desc_packed are in a union struct

		 * so q->vring.desc can replace q->vring.desc_packed.

		 */

		if (q->vring.desc != NULL && q->vring.size > 0) {

			rte_vhost_vring_call(vsession->vid, q->vring_idx);

		}

lib/vhost/vhost_internal.h

+13 −1
Original line number Diff line number Diff line
@@ -68,7 +68,6 @@ 
 */

#define SPDK_VHOST_COALESCING_DELAY_BASE_US 0





#define SPDK_VHOST_FEATURES ((1ULL << VHOST_F_LOG_ALL) | \

	(1ULL << VHOST_USER_F_PROTOCOL_FEATURES) | \

	(1ULL << VIRTIO_F_VERSION_1) | \
@@ -88,6 +87,19 @@ struct spdk_vhost_virtqueue { 
	uint16_t last_avail_idx;

	uint16_t last_used_idx;



	struct {

		/* To mark a descriptor as available in packed ring

		 * Equal to avail_wrap_counter in spec.

		 */

		uint8_t avail_phase	: 1;

		/* To mark a descriptor as used in packed ring

		 * Equal to used_wrap_counter in spec.

		 */

		uint8_t used_phase	: 1;

		uint8_t padding		: 5;

		bool packed_ring	: 1;

	} packed;



	void *tasks;



	/* Request count from last stats check */