nvmf/vfio-user: add poll group stats (954b145b) · Commits · Public Repositories / spdk

lib/nvmf/vfio_user.c

+122 −2

Original line number	Diff line number	Diff line
		@@ -355,6 +355,60 @@ struct nvmf_vfio_user_poll_group {
		TAILQ_HEAD(, nvmf_vfio_user_sq) sqs;
		struct spdk_interrupt *intr;
		int intr_fd;
		struct {

		/*
		* ctrlr_intr and ctrlr_kicks will be zero for all other poll
		* groups. However, they can be zero even for the poll group
		* the controller belongs are if no vfio-user message has been
		* received or the controller hasn't been kicked yet.
		*/

		/*
		* Number of times vfio_user_ctrlr_intr() has run:
		* vfio-user file descriptor has been ready or explicitly
		* kicked (see below).
		*/
		uint64_t ctrlr_intr;

		/*
		* Kicks to the controller by ctrlr_kick().
		* ctrlr_intr - ctrlr_kicks is the number of times the
		* vfio-user poll file descriptor has been ready.
		*/
		uint64_t ctrlr_kicks;

		/*
		* How many times we won the race arming an SQ.
		*/
		uint64_t won;

		/*
		* How many times we lost the race arming an SQ
		*/
		uint64_t lost;

		/*
		* How many requests we processed in total each time we lost
		* the rearm race.
		*/
		uint64_t lost_count;

		/*
		* Number of attempts we attempted to rearm all the SQs in the
		* poll group.
		*/
		uint64_t rearms;

		uint64_t pg_process_count;
		uint64_t intr;
		uint64_t polls;
		uint64_t polls_spurious;
		uint64_t poll_reqs;
		uint64_t poll_reqs_squared;
		uint64_t cqh_admin_writes;
		uint64_t cqh_io_writes;
		} stats;
		};

		struct nvmf_vfio_user_shadow_doorbells {
		@@ -665,6 +719,11 @@ static int vfio_user_ctrlr_intr(void *ctx);
		static void
		vfio_user_msg_ctrlr_intr(void *ctx)
		{
		struct nvmf_vfio_user_ctrlr *vu_ctrlr = ctx;
		struct nvmf_vfio_user_poll_group *vu_ctrlr_group = ctrlr_to_poll_group(vu_ctrlr);

		vu_ctrlr_group->stats.ctrlr_kicks++;

		vfio_user_ctrlr_intr(ctx);
		}

		@@ -1493,7 +1552,8 @@ static int nvmf_vfio_user_sq_poll(struct nvmf_vfio_user_sq *sq);
		*/
		static int
		vfio_user_sq_rearm(struct nvmf_vfio_user_ctrlr *ctrlr,
		struct nvmf_vfio_user_sq *sq)
		struct nvmf_vfio_user_sq *sq,
		struct nvmf_vfio_user_poll_group *vu_group)
		{
		int count = 0;
		size_t i;
		@@ -1505,6 +1565,7 @@ vfio_user_sq_rearm(struct nvmf_vfio_user_ctrlr *ctrlr,

		if (set_sq_eventidx(sq)) {
		/* We won the race and set eventidx; done. */
		vu_group->stats.won++;
		return count;
		}

		@@ -1532,6 +1593,9 @@ vfio_user_sq_rearm(struct nvmf_vfio_user_ctrlr *ctrlr,
		"%s: set_sq_eventidx() lost the race %zu times\n",
		ctrlr_id(ctrlr), i);

		vu_group->stats.lost++;
		vu_group->stats.lost_count += count;

		/*
		* We couldn't arrange an eventidx guaranteed to cause a BAR0 write, as
		* we raced with the producer too many times; force ourselves to wake up
		@@ -1556,13 +1620,15 @@ vfio_user_poll_group_rearm(struct nvmf_vfio_user_poll_group *vu_group)
		struct nvmf_vfio_user_sq *sq;
		int count = 0;

		vu_group->stats.rearms++;

		TAILQ_FOREACH(sq, &vu_group->sqs, link) {
		if (spdk_unlikely(sq->sq_state != VFIO_USER_SQ_ACTIVE \|\| !sq->size)) {
		continue;
		}

		if (sq->need_rearm) {
		count += vfio_user_sq_rearm(sq->ctrlr, sq);
		count += vfio_user_sq_rearm(sq->ctrlr, sq, vu_group);
		}
		}

		@@ -2794,6 +2860,8 @@ static int
		handle_dbl_access(struct nvmf_vfio_user_ctrlr ctrlr, uint32_t buf,
		const size_t count, loff_t pos, const bool is_write)
		{
		struct nvmf_vfio_user_poll_group *group;

		assert(ctrlr != NULL);
		assert(buf != NULL);

		@@ -2832,6 +2900,13 @@ handle_dbl_access(struct nvmf_vfio_user_ctrlr ctrlr, uint32_t buf,
		ctrlr->bar0_doorbells[pos] = *buf;
		spdk_wmb();

		group = ctrlr_to_poll_group(ctrlr);
		if (pos == 1) {
		group->stats.cqh_admin_writes++;
		} else if (pos & 1) {
		group->stats.cqh_io_writes++;
		}

		SPDK_DEBUGLOG(vfio_user_db, "%s: updating BAR0 doorbell %s:%ld to %u\n",
		ctrlr_id(ctrlr), (pos & 1) ? "cqid" : "sqid",
		pos / 2, *buf);
		@@ -4841,6 +4916,7 @@ vfio_user_poll_group_process(void *ctx)
		*/
		ret \|= vfio_user_poll_group_rearm(vu_group);

		vu_group->stats.pg_process_count++;
		return ret != 0 ? SPDK_POLLER_BUSY : SPDK_POLLER_IDLE;
		}

		@@ -4851,6 +4927,9 @@ vfio_user_poll_group_intr(void *ctx)
		eventfd_t val;

		eventfd_read(vu_group->intr_fd, &val);

		vu_group->stats.intr++;

		return vfio_user_poll_group_process(ctx);
		}

		@@ -4871,6 +4950,8 @@ vfio_user_ctrlr_intr(void *ctx)

		SPDK_DEBUGLOG(vfio_user_db, "ctrlr pg:%p got intr\n", vu_ctrlr_group);

		vu_ctrlr_group->stats.ctrlr_intr++;

		/*
		* Poll vfio-user for this controller. We need to do this before polling
		* any SQs, as this is where doorbell writes may be handled.
		@@ -5596,6 +5677,13 @@ nvmf_vfio_user_poll_group_poll(struct spdk_nvmf_transport_poll_group *group)
		count += ret;
		}

		vu_group->stats.polls++;
		vu_group->stats.poll_reqs += count;
		vu_group->stats.poll_reqs_squared += count * count;
		if (count == 0) {
		vu_group->stats.polls_spurious++;
		}

		return count;
		}

		@@ -5664,6 +5752,36 @@ nvmf_vfio_user_qpair_abort_request(struct spdk_nvmf_qpair *qpair,
		nvmf_ctrlr_abort_request(req);
		}

		static void
		nvmf_vfio_user_poll_group_dump_stat(struct spdk_nvmf_transport_poll_group *group,
		struct spdk_json_write_ctx *w)
		{
		struct nvmf_vfio_user_poll_group *vu_group = SPDK_CONTAINEROF(group,
		struct nvmf_vfio_user_poll_group, group);
		uint64_t polls_denom;

		spdk_json_write_named_uint64(w, "ctrlr_intr", vu_group->stats.ctrlr_intr);
		spdk_json_write_named_uint64(w, "ctrlr_kicks", vu_group->stats.ctrlr_kicks);
		spdk_json_write_named_uint64(w, "won", vu_group->stats.won);
		spdk_json_write_named_uint64(w, "lost", vu_group->stats.lost);
		spdk_json_write_named_uint64(w, "lost_count", vu_group->stats.lost_count);
		spdk_json_write_named_uint64(w, "rearms", vu_group->stats.rearms);
		spdk_json_write_named_uint64(w, "pg_process_count", vu_group->stats.pg_process_count);
		spdk_json_write_named_uint64(w, "intr", vu_group->stats.intr);
		spdk_json_write_named_uint64(w, "polls", vu_group->stats.polls);
		spdk_json_write_named_uint64(w, "polls_spurious", vu_group->stats.polls_spurious);
		spdk_json_write_named_uint64(w, "poll_reqs", vu_group->stats.poll_reqs);
		polls_denom = vu_group->stats.polls * (vu_group->stats.polls - 1);
		if (polls_denom) {
		uint64_t n = vu_group->stats.polls * vu_group->stats.poll_reqs_squared - vu_group->stats.poll_reqs *
		vu_group->stats.poll_reqs;
		spdk_json_write_named_double(w, "poll_reqs_variance", sqrt(n / polls_denom));
		}

		spdk_json_write_named_uint64(w, "cqh_admin_writes", vu_group->stats.cqh_admin_writes);
		spdk_json_write_named_uint64(w, "cqh_io_writes", vu_group->stats.cqh_io_writes);
		}

		static void
		nvmf_vfio_user_opts_init(struct spdk_nvmf_transport_opts *opts)
		{
		@@ -5708,6 +5826,8 @@ const struct spdk_nvmf_transport_ops spdk_nvmf_transport_vfio_user = {
		.qpair_get_peer_trid = nvmf_vfio_user_qpair_get_peer_trid,
		.qpair_get_listen_trid = nvmf_vfio_user_qpair_get_listen_trid,
		.qpair_abort_request = nvmf_vfio_user_qpair_abort_request,

		.poll_group_dump_stat = nvmf_vfio_user_poll_group_dump_stat,
		};

		SPDK_NVMF_TRANSPORT_REGISTER(muser, &spdk_nvmf_transport_vfio_user);