Commit 8ef5cfc6 authored by Changpeng Liu's avatar Changpeng Liu Committed by Tomasz Zawadzki
Browse files

vhost: restart device when memory region changed 



There are cases for users to add a new memory region during
runtime, in earlier SPDK versions before 23.01, SPDK supported
this feature via restart the device for any new SET_MEM_TABLE
messages.  In the commit 23baa676 we removed this support to
start device only once, since users are still requiring this
feature, so adding it back.

For SEM_MEM_TABLE vhost-user message, DPDK will hold the
access lock of vring, we can't call `rte_vhost_vring_call`
in the DPDK vhost thread context, so use the non-block API
instead.

Fix issue #3132.

Change-Id: I6dcb427eb56b778d9804f89c5998b2179ea3a916
Signed-off-by: default avatarChangpeng Liu <changpeng.liu@intel.com>
Reviewed-on: https://review.spdk.io/gerrit/c/spdk/spdk/+/19932


Tested-by: default avatarSPDK CI Jenkins <sys_sgci@intel.com>
Reviewed-by: default avatarKonrad Sztyber <konrad.sztyber@intel.com>
Reviewed-by: default avatarTomasz Zawadzki <tomasz.zawadzki@intel.com>
Community-CI: Mellanox Build Bot
parent 91459140

lib/vhost/rte_vhost_user.c

+30 −4
Original line number Diff line number Diff line
@@ -358,7 +358,11 @@ vhost_vq_used_signal(struct spdk_vhost_session *vsession, 
		      "Queue %td - USED RING: sending IRQ: last used %"PRIu16"\n",

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



#if RTE_VERSION < RTE_VERSION_NUM(22, 11, 0, 0)

	if (rte_vhost_vring_call(vsession->vid, virtqueue->vring_idx) == 0) {

#else

	if (rte_vhost_vring_call_nonblock(vsession->vid, virtqueue->vring_idx) == 0) {

#endif

		/* interrupt signalled */

		virtqueue->req_cnt += virtqueue->used_req_cnt;

		virtqueue->used_req_cnt = 0;
@@ -1468,6 +1472,17 @@ extern_vhost_pre_msg_handler(int vid, void *_msg) 
		}

		pthread_mutex_unlock(&user_dev->lock);

		break;

	case VHOST_USER_SET_MEM_TABLE:

		pthread_mutex_lock(&user_dev->lock);

		if (vsession->started) {

			vsession->original_max_queues = vsession->max_queues;

			pthread_mutex_unlock(&user_dev->lock);

			g_spdk_vhost_ops.destroy_device(vid);

			vsession->needs_restart = true;

			break;

		}

		pthread_mutex_unlock(&user_dev->lock);

		break;

	case VHOST_USER_GET_CONFIG: {

		int rc = 0;
@@ -1520,10 +1535,6 @@ extern_vhost_post_msg_handler(int vid, void *_msg) 
	}

	user_dev = to_user_dev(vsession->vdev);



	if (msg->request == VHOST_USER_SET_MEM_TABLE) {

		vhost_register_memtable_if_required(vsession, vid);

	}



	switch (msg->request) {

	case VHOST_USER_SET_FEATURES:

		rc = vhost_get_negotiated_features(vid, &vsession->negotiated_features);
@@ -1557,6 +1568,21 @@ extern_vhost_post_msg_handler(int vid, void *_msg) 
		}

		pthread_mutex_unlock(&user_dev->lock);

		break;

	case VHOST_USER_SET_MEM_TABLE:

		vhost_register_memtable_if_required(vsession, vid);

		pthread_mutex_lock(&user_dev->lock);

		if (vsession->needs_restart) {

			vsession->needs_restart = false;

			pthread_mutex_unlock(&user_dev->lock);

			for (qid = 0; qid < vsession->original_max_queues; qid++) {

				enable_device_vq(vsession, qid);

			}

			vsession->original_max_queues = 0;

			g_spdk_vhost_ops.new_device(vid);

			break;

		}

		pthread_mutex_unlock(&user_dev->lock);

		break;

	default:

		break;

	}

lib/vhost/vhost_internal.h

+3 −0
Original line number Diff line number Diff line
@@ -116,12 +116,15 @@ struct spdk_vhost_session { 
	bool started;

	bool starting;

	bool interrupt_mode;

	bool needs_restart;



	struct rte_vhost_memory *mem;



	int task_cnt;



	uint16_t max_queues;

	/* Maximum number of queues before restart, used with 'needs_restart' flag */

	uint16_t original_max_queues;



	uint64_t negotiated_features;

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

+4 −0
Original line number Diff line number Diff line
@@ -24,7 +24,11 @@ DEFINE_STUB(rte_vhost_get_vring_base, int, (int vid, uint16_t queue_id, 
		uint16_t *last_avail_idx, uint16_t *last_used_idx), 0);

DEFINE_STUB(spdk_mem_register, int, (void *vaddr, size_t len), 0);

DEFINE_STUB(spdk_mem_unregister, int, (void *vaddr, size_t len), 0);

#if RTE_VERSION < RTE_VERSION_NUM(22, 11, 0, 0)

DEFINE_STUB(rte_vhost_vring_call, int, (int vid, uint16_t vring_idx), 0);

#else

DEFINE_STUB(rte_vhost_vring_call_nonblock, int, (int vid, uint16_t vring_idx), 0);

#endif

DEFINE_STUB_V(rte_vhost_log_used_vring, (int vid, uint16_t vring_idx,

		uint64_t offset, uint64_t len));