Commit e28ac3bc authored by Jin Yu's avatar Jin Yu Committed by Tomasz Zawadzki
Browse files

vhost-blk: record inflight descs of packed ring 

This patch is for packed ring live recovery.
First step is to track the packed ring descs.

This feature base on this QEMU patch:
https://patchwork.kernel.org/patch/11766697/



Change-Id: Id0ccb6fd12b3623cc367424f496b4ffc5323f390
Signed-off-by: default avatarJin Yu <jin.yu@intel.com>
Reviewed-on: https://review.spdk.io/gerrit/c/spdk/spdk/+/4126


Tested-by: default avatarSPDK CI Jenkins <sys_sgci@intel.com>
Reviewed-by: default avatarChangpeng Liu <changpeng.liu@intel.com>
Reviewed-by: default avatarShuhei Matsumoto <shuhei.matsumoto.xt@hitachi.com>
parent c73dc155

lib/vhost/vhost.c

+4 −1
Original line number Diff line number Diff line
@@ -546,7 +546,7 @@ void 
vhost_vq_packed_ring_enqueue(struct spdk_vhost_session *vsession,

			     struct spdk_vhost_virtqueue *virtqueue,

			     uint16_t num_descs, uint16_t buffer_id,

			     uint32_t length)

			     uint32_t length, uint16_t inflight_head)

{

	struct vring_packed_desc *desc = &virtqueue->vring.desc_packed[virtqueue->last_used_idx];

	bool used, avail;
@@ -587,6 +587,8 @@ vhost_vq_packed_ring_enqueue(struct spdk_vhost_session *vsession, 
	 * written to the descriptor.

	 */

	spdk_smp_wmb();



	rte_vhost_set_last_inflight_io_packed(vsession->vid, virtqueue->vring_idx, inflight_head);

	/* To mark a desc as used, the device sets the F_USED bit in flags to match

	 * the internal Device ring wrap counter. It also sets the F_AVAIL bit to

	 * match the same value.
@@ -596,6 +598,7 @@ vhost_vq_packed_ring_enqueue(struct spdk_vhost_session *vsession, 
	} else {

		desc->flags &= ~VRING_DESC_F_AVAIL_USED;

	}

	rte_vhost_clr_inflight_desc_packed(vsession->vid, virtqueue->vring_idx, inflight_head);



	vhost_log_used_vring_elem(vsession, virtqueue, virtqueue->last_used_idx);

	virtqueue->last_used_idx += num_descs;

lib/vhost/vhost_blk.c

+11 −3
Original line number Diff line number Diff line
@@ -72,6 +72,7 @@ struct spdk_vhost_blk_task { 
	uint16_t req_idx;

	uint16_t num_descs;

	uint16_t buffer_id;

	uint16_t inflight_head;



	/* for io wait */

	struct spdk_bdev_io_wait_entry bdev_io_wait;
@@ -141,7 +142,8 @@ blk_task_enqueue(struct spdk_vhost_blk_task *task) 
	if (task->vq->packed.packed_ring) {

		vhost_vq_packed_ring_enqueue(&task->bvsession->vsession, task->vq,

					     task->num_descs,

					     task->buffer_id, task->used_len);

					     task->buffer_id, task->used_len,

					     task->inflight_head);

	} else {

		vhost_vq_used_ring_enqueue(&task->bvsession->vsession, task->vq,

					   task->req_idx, task->used_len);
@@ -578,6 +580,10 @@ process_blk_task(struct spdk_vhost_virtqueue *vq, uint16_t req_idx) 
		task->req_idx = req_idx;

		task->num_descs = num_descs;

		task->buffer_id = task_idx;



		rte_vhost_set_inflight_desc_packed(task->bvsession->vsession.vid, vq->vring_idx,

						   req_idx, (req_idx + num_descs - 1) % vq->vring.size,

						   &task->inflight_head);

	}



	task->bvsession->vsession.task_cnt++;
@@ -752,7 +758,8 @@ no_bdev_process_packed_vq(struct spdk_vhost_blk_session *bvsession, struct spdk_ 
		SPDK_ERRLOG("%s: request with idx '%"PRIu16"' is already pending.\n",

			    vsession->name, req_idx);

		vhost_vq_packed_ring_enqueue(vsession, vq, num_descs,

					     task->buffer_id, task->used_len);

					     task->buffer_id, task->used_len,

					     task->inflight_head);

		return;

	}
@@ -769,7 +776,8 @@ no_bdev_process_packed_vq(struct spdk_vhost_blk_session *bvsession, struct spdk_ 


	task->used = false;

	vhost_vq_packed_ring_enqueue(vsession, vq, num_descs,

				     task->buffer_id, task->used_len);

				     task->buffer_id, task->used_len,

				     task->inflight_head);

}



static int

lib/vhost/vhost_internal.h

+2 −1
Original line number Diff line number Diff line
@@ -324,11 +324,12 @@ void vhost_vq_used_ring_enqueue(struct spdk_vhost_session *vsession, 
 * \buffer_id descriptor buffer ID.

 * \length device write length. Specify the length of the buffer that has been initialized

 * (written to) by the device

 * \inflight_head the head idx of this IO inflight desc chain.

 */

void vhost_vq_packed_ring_enqueue(struct spdk_vhost_session *vsession,

				  struct spdk_vhost_virtqueue *virtqueue,

				  uint16_t num_descs, uint16_t buffer_id,

				  uint32_t length);

				  uint32_t length, uint16_t inflight_head);



/**

 * Get subsequent descriptor from given table.

test/unit/lib/vhost/vhost.c/vhost_ut.c

+11 −7
Original line number Diff line number Diff line
@@ -75,6 +75,10 @@ DEFINE_STUB(rte_vhost_set_last_inflight_io_split, int, 
	    (int vid, uint16_t vring_idx, uint16_t idx), 0);

DEFINE_STUB(rte_vhost_clr_inflight_desc_split, int,

	    (int vid, uint16_t vring_idx, uint16_t last_used_idx, uint16_t idx), 0);

DEFINE_STUB(rte_vhost_set_last_inflight_io_packed, int,

	    (int vid, uint16_t vring_idx, uint16_t head), 0);

DEFINE_STUB(rte_vhost_clr_inflight_desc_packed, int,

	    (int vid, uint16_t vring_idx, uint16_t head), 0);

DEFINE_STUB_V(rte_vhost_log_write, (int vid, uint64_t addr, uint64_t len));

DEFINE_STUB_V(vhost_session_mem_register, (struct rte_vhost_memory *mem));

DEFINE_STUB_V(vhost_session_mem_unregister, (struct rte_vhost_memory *mem));
@@ -473,9 +477,9 @@ vq_packed_ring_test(void) 
	}



	/* Host complete them out of order: 1, 0, 2. */

	vhost_vq_packed_ring_enqueue(&vs, &vq, 1, 1, 1);

	vhost_vq_packed_ring_enqueue(&vs, &vq, 1, 0, 1);

	vhost_vq_packed_ring_enqueue(&vs, &vq, 1, 2, 1);

	vhost_vq_packed_ring_enqueue(&vs, &vq, 1, 1, 1, 0);

	vhost_vq_packed_ring_enqueue(&vs, &vq, 1, 0, 1, 0);

	vhost_vq_packed_ring_enqueue(&vs, &vq, 1, 2, 1, 0);



	/* Host has got all the available request but only complete three requests */

	CU_ASSERT(vq.last_avail_idx == 0);
@@ -511,10 +515,10 @@ vq_packed_ring_test(void) 
	CU_ASSERT(vq.packed.avail_phase == 0);



	/* Host complete all the requests */

	vhost_vq_packed_ring_enqueue(&vs, &vq, 1, 1, 1);

	vhost_vq_packed_ring_enqueue(&vs, &vq, 1, 0, 1);

	vhost_vq_packed_ring_enqueue(&vs, &vq, 1, 3, 1);

	vhost_vq_packed_ring_enqueue(&vs, &vq, 1, 2, 1);

	vhost_vq_packed_ring_enqueue(&vs, &vq, 1, 1, 1, 0);

	vhost_vq_packed_ring_enqueue(&vs, &vq, 1, 0, 1, 0);

	vhost_vq_packed_ring_enqueue(&vs, &vq, 1, 3, 1, 0);

	vhost_vq_packed_ring_enqueue(&vs, &vq, 1, 2, 1, 0);



	CU_ASSERT(vq.last_used_idx == vq.last_avail_idx);

	CU_ASSERT(vq.packed.used_phase == vq.packed.avail_phase);