[PATCH net-next] net: mana: Add support to process throttled EQEs

@@ -747,6 +747,18 @@ void mana_gd_free_service_wq(struct gdma_context *gc)
 	gc->service_wq = NULL;
 }

+static void mana_gd_schedule_eq_cqs(struct gdma_queue *eq)
+{
+	struct gdma_queue *cq;
+	u8 i;
+
+	for (i = 0; i < GDMA_EQ_MAX_CHILD_CQ; i++) {
+		cq = rcu_dereference(eq->eq.child_cq[i]);
+		if (cq && cq->cq.callback)
+			cq->cq.callback(cq->cq.context, cq);
+	}
+}
+
 static void mana_gd_process_eqe(struct gdma_queue *eq)
 {
 	u32 head = eq->head % (eq->queue_size / GDMA_EQE_SIZE);

@@ -777,6 +789,11 @@ static void mana_gd_process_eqe(struct gdma_queue *eq)

 		break;

+	case GDMA_EQE_THROTTLE:
+		eq->eq.throttle_count++;
+		mana_gd_schedule_eq_cqs(eq);
+		break;
+
 	case GDMA_EQE_TEST_EVENT:
 		gc->test_event_eq_id = eq->id;
 		complete(&gc->eq_test_event);

@@ -1063,17 +1080,41 @@ static void mana_gd_create_cq(const struct gdma_queue_spec *spec,
 			      struct gdma_queue *queue)
 {
 	u32 log2_num_entries = ilog2(spec->queue_size / GDMA_CQE_SIZE);
+	struct gdma_queue *parent;
+	u8 i;

 	queue->head |= INITIALIZED_OWNER_BIT(log2_num_entries);
-	queue->cq.parent = spec->cq.parent_eq;
+	parent = spec->cq.parent_eq;
+	queue->cq.parent = parent;
 	queue->cq.context = spec->cq.context;
 	queue->cq.callback = spec->cq.callback;
+
+	if (!parent)
+		return;
+
+	/* For throttled EQE store the child CQ */
+	for (i = 0; i < GDMA_EQ_MAX_CHILD_CQ; i++)
+		if (!rcu_access_pointer(parent->eq.child_cq[i])) {
+			rcu_assign_pointer(parent->eq.child_cq[i], queue);
+			return;
+		}
 }

 static void mana_gd_destroy_cq(struct gdma_context *gc,
 			       struct gdma_queue *queue)
 {
+	struct gdma_queue *parent = queue->cq.parent;
 	u32 id = queue->id;
+	u8 i;
+
+	if (parent) {
+		for (i = 0; i < GDMA_EQ_MAX_CHILD_CQ; i++) {
+			if (rcu_access_pointer(parent->eq.child_cq[i]) == queue)
+				RCU_INIT_POINTER(parent->eq.child_cq[i], NULL);
+		}
+
+		synchronize_rcu();
+	}

 	if (id >= gc->max_num_cqs)
 		return;

@@ -22,6 +22,8 @@ static const struct mana_stats_desc mana_eth_stats[] = {
 				       tx_linear_pkt_cnt)},
 	{"rx_cqe_unknown_type", offsetof(struct mana_ethtool_stats,
 					rx_cqe_unknown_type)},
+	{"eq_throttle_events", offsetof(struct mana_ethtool_stats,
+					eq_throttle_events)},
 };

 static const struct mana_stats_desc mana_hc_stats[] = {

@@ -261,6 +263,11 @@ static void mana_get_ethtool_stats(struct net_device *ndev,
 	 */
 	mana_query_phy_stats(apc);

+	apc->eth_stats.eq_throttle_events = 0;
+	for (q = 0; q < num_queues; q++)
+		apc->eth_stats.eq_throttle_events +=
+			apc->eqs[q].eq->eq.throttle_count;
+
 	for (q = 0; q < ARRAY_SIZE(mana_eth_stats); q++)
 		data[i++] = *(u64 *)(eth_stats + mana_eth_stats[q].offset);

@@ -58,6 +58,7 @@ enum gdma_work_request_flags {

 enum gdma_eqe_type {
 	GDMA_EQE_COMPLETION		= 3,
+	GDMA_EQE_THROTTLE		= 4,
 	GDMA_EQE_TEST_EVENT		= 64,
 	GDMA_EQE_HWC_INIT_EQ_ID_DB	= 129,
 	GDMA_EQE_HWC_INIT_DATA		= 130,

@@ -286,6 +287,7 @@ struct gdma_dev {
 #define GDMA_EQE_SIZE 16
 #define GDMA_MAX_SQE_SIZE 512
 #define GDMA_MAX_RQE_SIZE 256
+#define GDMA_EQ_MAX_CHILD_CQ  2

 #define GDMA_COMP_DATA_SIZE 0x3C

@@ -366,6 +368,10 @@ struct gdma_queue {
 			unsigned int irq;

 			u32 log2_throttle_limit;
+
+			u64 throttle_count;
+
+			struct gdma_queue __rcu *child_cq[GDMA_EQ_MAX_CHILD_CQ];
 		} eq;

 		struct {

@@ -752,6 +758,9 @@ enum {
 /* Driver supports non-contiguous queue buffers */
 #define GDMA_DRV_CAP_FLAG_1_NON_CONTIGUOUS_BUFFERS BIT(30)

+/* Driver supports handling throttled EQEs */
+#define GDMA_DRV_CAP_FLAG_1_THROTTLED_EVENT_QUEUE BIT_ULL(32)
+
 /* Capabilities in the PCI-only group below rely on dynamic MSI-X allocation
  * and on the servicing and reset paths reached through
  * mana_schedule_serv_work(). Transports that provide neither leave

@@ -776,7 +785,8 @@ enum {
 	 GDMA_DRV_CAP_FLAG_1_HANDLE_STALL_SQ_RECOVERY | \
 	 GDMA_DRV_CAP_FLAG_1_EQ_MSI_UNSHARE_MULTI_VPORT | \
 	 GDMA_DRV_CAP_FLAG_1_DYN_INTERRUPT_MODERATION | \
-	 GDMA_DRV_CAP_FLAG_1_NON_CONTIGUOUS_BUFFERS)
+	 GDMA_DRV_CAP_FLAG_1_NON_CONTIGUOUS_BUFFERS | \
+	 GDMA_DRV_CAP_FLAG_1_THROTTLED_EVENT_QUEUE)

 #define GDMA_DRV_CAP_FLAGS2 0

@@ -439,6 +439,7 @@ struct mana_ethtool_stats {
 	u64 tx_cqe_unknown_type;
 	u64 tx_linear_pkt_cnt;
 	u64 rx_cqe_unknown_type;
+	u64 eq_throttle_events;
 };

 struct mana_ethtool_hc_stats {
--