Commit fce2956c authored by Liu Xiaodong's avatar Liu Xiaodong Committed by Jim Harris
Browse files

vhost: always acknowledge kickfd in intr 



kickfd of virtvq should be akcnowledged firstly in
vhost_vq_avail_ring_get function, in case there is
no available requests then kickfd won't get acked.

Change-Id: I9c2f0cc19be9da54649991ddab5a5b5640ed941a
Signed-off-by: default avatarLiu Xiaodong <xiaodong.liu@intel.com>
Reviewed-on: https://review.spdk.io/gerrit/c/spdk/spdk/+/5780


Tested-by: default avatarSPDK CI Jenkins <sys_sgci@intel.com>
Community-CI: Mellanox Build Bot
Reviewed-by: default avatarChangpeng Liu <changpeng.liu@intel.com>
Reviewed-by: default avatarJim Harris <james.r.harris@intel.com>
parent f8330a57

lib/vhost/vhost.c

+18 −19
Original line number Diff line number Diff line
@@ -183,9 +183,26 @@ vhost_vq_avail_ring_get(struct spdk_vhost_virtqueue *virtqueue, uint16_t *reqs, 
	uint16_t size_mask = vring->size - 1;

	uint16_t last_idx = virtqueue->last_avail_idx, avail_idx = avail->idx;

	uint16_t count, i;

	int rc;

	uint64_t num_events;



	spdk_smp_rmb();



	if (virtqueue->vsession && spdk_unlikely(virtqueue->vsession->interrupt_mode)) {

		/* Acknowledge vring's kickfd */

		rc = read(vring->kickfd, &num_events, sizeof(num_events));

		if (rc < 0) {

			SPDK_ERRLOG("failed to acknowledge kickfd: %s.\n", spdk_strerror(errno));

			return -errno;

		}



		if ((uint16_t)(avail_idx - last_idx) != num_events) {

			SPDK_DEBUGLOG(vhost_ring,

				      "virtqueue gets %d reqs, but kickfd shows %lu reqs\n",

				      avail_idx - last_idx, num_events);

		}

	}



	count = avail_idx - last_idx;

	if (spdk_likely(count == 0)) {

		return 0;
@@ -199,25 +216,7 @@ vhost_vq_avail_ring_get(struct spdk_vhost_virtqueue *virtqueue, uint16_t *reqs, 
	}



	count = spdk_min(count, reqs_len);

	if (virtqueue->vsession && virtqueue->vsession->interrupt_mode) {

		/* if completed IO number is larger than SPDK_AIO_QUEUE_DEPTH,

		 * io_getevent should be called again to ensure all completed IO are processed.

		 */

		int rc;

		uint64_t num_events;



		rc = read(vring->kickfd, &num_events, sizeof(num_events));

		if (rc < 0) {

			SPDK_ERRLOG("failed to acknowledge kickfd: %s.\n", spdk_strerror(errno));

			return -errno;

		}



		if ((uint16_t)(avail_idx - last_idx) != num_events) {

			SPDK_DEBUGLOG(vhost_ring,

				      "virtqueue gets %d reqs, but kickfd shows %lu reqs\n",

				      avail_idx - last_idx, num_events);

		}



	if (virtqueue->vsession && spdk_unlikely(virtqueue->vsession->interrupt_mode)) {

		if (num_events > count) {

			SPDK_DEBUGLOG(vhost_ring,

				      "virtqueue kickfd shows %lu reqs, take %d, send notice for other reqs\n",