IB/mlx5: Add port protocol stats

Expose new counters using the get protocol stats callback.
We expose the following counters:

|------------------------------------------------------------------------|
|      Name           | IB | EN |           Description                  |
|------------------------------------------------------------------------|
|rx_write_requests    | +  | -  | Number of received WRITE requests for  |
|                     |    |    | the associated QP.                     |
|------------------------------------------------------------------------|
|rx_read_requests     | +  | -  | Number of received READ requests for   |
|                     |    |    | the associated QP.                     |
|------------------------------------------------------------------------|
|rx_atomic_requests   | +  | -  | Number of received ATOMIC requests for |
|                     |    |    | the associated QP.                     |
|------------------------------------------------------------------------|
|out_of_buffer        | +  | +  | Number of drops occurred due to lack   |
|                     |    |    | of WQE for the associated QPs/RQs.     |
|------------------------------------------------------------------------|
|out_of_sequence      | +  | -  | Number of errors in the packet         |
|                     |    |    | transport sequence number              |
|------------------------------------------------------------------------|
|duplicate_request    | +  | +  | Number of received duplicated packets. |
|                     |    |    | A request that previously executed is  |
|                     |    |    | named duplicated.                      |
|------------------------------------------------------------------------|
|rnr_nak_retry_err    | +  | +  | Number of received RNR NAC packets.    |
|                     |    |    | The QP retry limit did not exceed.     |
|------------------------------------------------------------------------|
|packet_seq_err       | +  | +  | Number of received NAK - sequence error|
|                     |    |    | packets. The QP retry limit did not    |
|                     |    |    | exceed.                                |
|------------------------------------------------------------------------|
|implied_nak_err      | +  | +  | Number of times the requester detected |
|                     |    |    | an ACK with a PSN larger than expected |
|                     |    |    | PSN for RDMA READ or ATOMIC response   |
|                     |    |    | The QP retry limit did not exceed.     |
|------------------------------------------------------------------------|
|local_ack_timeout_err| +  | -  | Number of NO ACK responses from        |
|                     |    |    | responder within timer interval.       |
|                     |    |    | The QP retry limit did not exceed.     |
|------------------------------------------------------------------------|

Counters are available if all of them are supported.
Signed-off-by: Mark Bloch <markb@mellanox.com>
Signed-off-by: Leon Romanovsky <leonro@mellanox.com>
Signed-off-by: Leon Romanovsky <leon@kernel.org>
Reviewed-by: Christoph Lameter <cl@linux.com>
Signed-off-by: Doug Ledford <dledford@redhat.com>

drivers/infiniband/hw/mlx5/main.c

@@ -2576,6 +2576,78 @@ static int mlx5_ib_alloc_q_counters(struct mlx5_ib_dev *dev)
 	return ret;
 }
 
+static const char const *names[] = {
+	"rx_write_requests",
+	"rx_read_requests",
+	"rx_atomic_requests",
+	"out_of_buffer",
+	"out_of_sequence",
+	"duplicate_request",
+	"rnr_nak_retry_err",
+	"packet_seq_err",
+	"implied_nak_seq_err",
+	"local_ack_timeout_err",
+};
+
+static const size_t stats_offsets[] = {
+	MLX5_BYTE_OFF(query_q_counter_out, rx_write_requests),
+	MLX5_BYTE_OFF(query_q_counter_out, rx_read_requests),
+	MLX5_BYTE_OFF(query_q_counter_out, rx_atomic_requests),
+	MLX5_BYTE_OFF(query_q_counter_out, out_of_buffer),
+	MLX5_BYTE_OFF(query_q_counter_out, out_of_sequence),
+	MLX5_BYTE_OFF(query_q_counter_out, duplicate_request),
+	MLX5_BYTE_OFF(query_q_counter_out, rnr_nak_retry_err),
+	MLX5_BYTE_OFF(query_q_counter_out, packet_seq_err),
+	MLX5_BYTE_OFF(query_q_counter_out, implied_nak_seq_err),
+	MLX5_BYTE_OFF(query_q_counter_out, local_ack_timeout_err),
+};
+
+static struct rdma_hw_stats *mlx5_ib_alloc_hw_stats(struct ib_device *ibdev,
+						    u8 port_num)
+{
+	BUILD_BUG_ON(ARRAY_SIZE(names) != ARRAY_SIZE(stats_offsets));
+
+	/* We support only per port stats */
+	if (port_num == 0)
+		return NULL;
+
+	return rdma_alloc_hw_stats_struct(names, ARRAY_SIZE(names),
+					  RDMA_HW_STATS_DEFAULT_LIFESPAN);
+}
+
+static int mlx5_ib_get_hw_stats(struct ib_device *ibdev,
+				struct rdma_hw_stats *stats,
+				u8 port, int index)
+{
+	struct mlx5_ib_dev *dev = to_mdev(ibdev);
+	int outlen = MLX5_ST_SZ_BYTES(query_q_counter_out);
+	void *out;
+	__be32 val;
+	int ret;
+	int i;
+
+	if (!port || !stats)
+		return -ENOSYS;
+
+	out = mlx5_vzalloc(outlen);
+	if (!out)
+		return -ENOMEM;
+
+	ret = mlx5_core_query_q_counter(dev->mdev,
+					dev->port[port - 1].q_cnt_id, 0,
+					out, outlen);
+	if (ret)
+		goto free;
+
+	for (i = 0; i < ARRAY_SIZE(names); i++) {
+		val = *(__be32 *)(out + stats_offsets[i]);
+		stats->value[i] = (u64)be32_to_cpu(val);
+	}
+free:
+	kvfree(out);
+	return ARRAY_SIZE(names);
+}
+
 static void *mlx5_ib_add(struct mlx5_core_dev *mdev)
 {
 	struct mlx5_ib_dev *dev;
@@ -2720,6 +2792,12 @@ static void *mlx5_ib_add(struct mlx5_core_dev *mdev)
 			(1ull << IB_USER_VERBS_CMD_DEALLOC_MW);
 	}
 
+	if (MLX5_CAP_GEN(dev->mdev, out_of_seq_cnt) &&
+	    MLX5_CAP_GEN(dev->mdev, retransmission_q_counters)) {
+		dev->ib_dev.get_hw_stats	= mlx5_ib_get_hw_stats;
+		dev->ib_dev.alloc_hw_stats	= mlx5_ib_alloc_hw_stats;
+	}
+
 	if (MLX5_CAP_GEN(mdev, xrc)) {
 		dev->ib_dev.alloc_xrcd = mlx5_ib_alloc_xrcd;
 		dev->ib_dev.dealloc_xrcd = mlx5_ib_dealloc_xrcd;