[PATCH v3 2/2] vdpa/mlx5: Add support for reading descriptor statistics

From: Eli Cohen
Date: Mon May 02 2022 - 06:22:35 EST


Implement the get_vq_stats calback of vdpa_config_ops to return the
statistics for a virtqueue.

The statistics are provided as vendor specific statistics where the
driver provides a pair of attribute name and attribute value.

In addition to the attribute name/attribute value pair, the driver
returns the negotiated features and max virtqueue pairs for userspace
can decide for a given queue index whether it is a data or control
virtqueue.

Currently supported are received descriptors and completed descriptors.

Acked-by: Jason Wang <jasowang@xxxxxxxxxx>
Signed-off-by: Eli Cohen <elic@xxxxxxxxxx>

v2 -> v3:
Fix sparse warning
---
drivers/vdpa/mlx5/core/mlx5_vdpa.h | 2 +
drivers/vdpa/mlx5/net/mlx5_vnet.c | 165 +++++++++++++++++++++++++++++
include/linux/mlx5/mlx5_ifc.h | 1 +
include/linux/mlx5/mlx5_ifc_vdpa.h | 39 +++++++
4 files changed, 207 insertions(+)

diff --git a/drivers/vdpa/mlx5/core/mlx5_vdpa.h b/drivers/vdpa/mlx5/core/mlx5_vdpa.h
index daaf7b503677..44104093163b 100644
--- a/drivers/vdpa/mlx5/core/mlx5_vdpa.h
+++ b/drivers/vdpa/mlx5/core/mlx5_vdpa.h
@@ -61,6 +61,8 @@ struct mlx5_control_vq {
struct vringh_kiov riov;
struct vringh_kiov wiov;
unsigned short head;
+ unsigned int received_desc;
+ unsigned int completed_desc;
};

struct mlx5_vdpa_wq_ent {
diff --git a/drivers/vdpa/mlx5/net/mlx5_vnet.c b/drivers/vdpa/mlx5/net/mlx5_vnet.c
index 79001301b383..473ec481813c 100644
--- a/drivers/vdpa/mlx5/net/mlx5_vnet.c
+++ b/drivers/vdpa/mlx5/net/mlx5_vnet.c
@@ -119,6 +119,7 @@ struct mlx5_vdpa_virtqueue {
struct mlx5_vdpa_umem umem2;
struct mlx5_vdpa_umem umem3;

+ u32 counter_set_id;
bool initialized;
int index;
u32 virtq_id;
@@ -164,6 +165,8 @@ struct mlx5_vdpa_net {
struct notifier_block nb;
struct vdpa_callback config_cb;
struct mlx5_vdpa_wq_ent cvq_ent;
+ /* sync access to virtqueues statistics */
+ struct mutex numq_lock;
};

static void free_resources(struct mlx5_vdpa_net *ndev);
@@ -822,6 +825,12 @@ static u16 get_features_12_3(u64 features)
(!!(features & BIT_ULL(VIRTIO_NET_F_GUEST_CSUM)) << 6);
}

+static bool counters_supported(const struct mlx5_vdpa_dev *mvdev)
+{
+ return MLX5_CAP_GEN_64(mvdev->mdev, general_obj_types) &
+ BIT_ULL(MLX5_OBJ_TYPE_VIRTIO_Q_COUNTERS);
+}
+
static int create_virtqueue(struct mlx5_vdpa_net *ndev, struct mlx5_vdpa_virtqueue *mvq)
{
int inlen = MLX5_ST_SZ_BYTES(create_virtio_net_q_in);
@@ -876,6 +885,8 @@ static int create_virtqueue(struct mlx5_vdpa_net *ndev, struct mlx5_vdpa_virtque
MLX5_SET(virtio_q, vq_ctx, umem_3_id, mvq->umem3.id);
MLX5_SET(virtio_q, vq_ctx, umem_3_size, mvq->umem3.size);
MLX5_SET(virtio_q, vq_ctx, pd, ndev->mvdev.res.pdn);
+ if (counters_supported(&ndev->mvdev))
+ MLX5_SET(virtio_q, vq_ctx, counter_set_id, mvq->counter_set_id);

err = mlx5_cmd_exec(ndev->mvdev.mdev, in, inlen, out, sizeof(out));
if (err)
@@ -1139,6 +1150,47 @@ static int modify_virtqueue(struct mlx5_vdpa_net *ndev, struct mlx5_vdpa_virtque
return err;
}

+static int counter_set_alloc(struct mlx5_vdpa_net *ndev, struct mlx5_vdpa_virtqueue *mvq)
+{
+ u32 in[MLX5_ST_SZ_DW(create_virtio_q_counters_in)] = {};
+ u32 out[MLX5_ST_SZ_DW(create_virtio_q_counters_out)] = {};
+ void *cmd_hdr;
+ int err;
+
+ if (!counters_supported(&ndev->mvdev))
+ return 0;
+
+ cmd_hdr = MLX5_ADDR_OF(create_virtio_q_counters_in, in, hdr);
+
+ MLX5_SET(general_obj_in_cmd_hdr, cmd_hdr, opcode, MLX5_CMD_OP_CREATE_GENERAL_OBJECT);
+ MLX5_SET(general_obj_in_cmd_hdr, cmd_hdr, obj_type, MLX5_OBJ_TYPE_VIRTIO_Q_COUNTERS);
+ MLX5_SET(general_obj_in_cmd_hdr, cmd_hdr, uid, ndev->mvdev.res.uid);
+
+ err = mlx5_cmd_exec(ndev->mvdev.mdev, in, sizeof(in), out, sizeof(out));
+ if (err)
+ return err;
+
+ mvq->counter_set_id = MLX5_GET(general_obj_out_cmd_hdr, out, obj_id);
+
+ return 0;
+}
+
+static void counter_set_dealloc(struct mlx5_vdpa_net *ndev, struct mlx5_vdpa_virtqueue *mvq)
+{
+ u32 in[MLX5_ST_SZ_DW(destroy_virtio_q_counters_in)] = {};
+ u32 out[MLX5_ST_SZ_DW(destroy_virtio_q_counters_out)] = {};
+
+ if (!counters_supported(&ndev->mvdev))
+ return;
+
+ MLX5_SET(destroy_virtio_q_counters_in, in, hdr.opcode, MLX5_CMD_OP_DESTROY_GENERAL_OBJECT);
+ MLX5_SET(destroy_virtio_q_counters_in, in, hdr.obj_id, mvq->counter_set_id);
+ MLX5_SET(destroy_virtio_q_counters_in, in, hdr.uid, ndev->mvdev.res.uid);
+ MLX5_SET(destroy_virtio_q_counters_in, in, hdr.obj_type, MLX5_OBJ_TYPE_VIRTIO_Q_COUNTERS);
+ if (mlx5_cmd_exec(ndev->mvdev.mdev, in, sizeof(in), out, sizeof(out)))
+ mlx5_vdpa_warn(&ndev->mvdev, "dealloc counter set 0x%x\n", mvq->counter_set_id);
+}
+
static int setup_vq(struct mlx5_vdpa_net *ndev, struct mlx5_vdpa_virtqueue *mvq)
{
u16 idx = mvq->index;
@@ -1166,6 +1218,10 @@ static int setup_vq(struct mlx5_vdpa_net *ndev, struct mlx5_vdpa_virtqueue *mvq)
if (err)
goto err_connect;

+ err = counter_set_alloc(ndev, mvq);
+ if (err)
+ goto err_counter;
+
err = create_virtqueue(ndev, mvq);
if (err)
goto err_connect;
@@ -1183,6 +1239,8 @@ static int setup_vq(struct mlx5_vdpa_net *ndev, struct mlx5_vdpa_virtqueue *mvq)
return 0;

err_connect:
+ counter_set_dealloc(ndev, mvq);
+err_counter:
qp_destroy(ndev, &mvq->vqqp);
err_vqqp:
qp_destroy(ndev, &mvq->fwqp);
@@ -1227,6 +1285,7 @@ static void teardown_vq(struct mlx5_vdpa_net *ndev, struct mlx5_vdpa_virtqueue *

suspend_vq(ndev, mvq);
destroy_virtqueue(ndev, mvq);
+ counter_set_dealloc(ndev, mvq);
qp_destroy(ndev, &mvq->vqqp);
qp_destroy(ndev, &mvq->fwqp);
cq_destroy(ndev, mvq->index);
@@ -1633,8 +1692,10 @@ static virtio_net_ctrl_ack handle_ctrl_mq(struct mlx5_vdpa_dev *mvdev, u8 cmd)
break;
}

+ mutex_lock(&ndev->numq_lock);
if (!change_num_qps(mvdev, newqps))
status = VIRTIO_NET_OK;
+ mutex_unlock(&ndev->numq_lock);

break;
default:
@@ -1681,6 +1742,7 @@ static void mlx5_cvq_kick_handler(struct work_struct *work)
if (read != sizeof(ctrl))
break;

+ cvq->received_desc++;
switch (ctrl.class) {
case VIRTIO_NET_CTRL_MAC:
status = handle_ctrl_mac(mvdev, ctrl.cmd);
@@ -1704,6 +1766,7 @@ static void mlx5_cvq_kick_handler(struct work_struct *work)
if (vringh_need_notify_iotlb(&cvq->vring))
vringh_notify(&cvq->vring);

+ cvq->completed_desc++;
queue_work(mvdev->wq, &wqent->work);
break;
}
@@ -2323,6 +2386,8 @@ static int mlx5_vdpa_reset(struct vdpa_device *vdev)
mlx5_vdpa_destroy_mr(&ndev->mvdev);
ndev->mvdev.status = 0;
ndev->cur_num_vqs = 0;
+ ndev->mvdev.cvq.received_desc = 0;
+ ndev->mvdev.cvq.completed_desc = 0;
memset(ndev->event_cbs, 0, sizeof(*ndev->event_cbs) * (mvdev->max_vqs + 1));
ndev->mvdev.actual_features = 0;
++mvdev->generation;
@@ -2401,6 +2466,7 @@ static void mlx5_vdpa_free(struct vdpa_device *vdev)
mlx5_mpfs_del_mac(pfmdev, ndev->config.mac);
}
mlx5_vdpa_free_resources(&ndev->mvdev);
+ mutex_destroy(&ndev->numq_lock);
mutex_destroy(&ndev->reslock);
kfree(ndev->event_cbs);
kfree(ndev->vqs);
@@ -2442,6 +2508,102 @@ static u64 mlx5_vdpa_get_driver_features(struct vdpa_device *vdev)
return mvdev->actual_features;
}

+static int counter_set_query(struct mlx5_vdpa_net *ndev, struct mlx5_vdpa_virtqueue *mvq,
+ u64 *received_desc, u64 *completed_desc)
+{
+ u32 in[MLX5_ST_SZ_DW(query_virtio_q_counters_in)] = {};
+ u32 out[MLX5_ST_SZ_DW(query_virtio_q_counters_out)] = {};
+ void *cmd_hdr;
+ void *ctx;
+ int err;
+
+ if (!counters_supported(&ndev->mvdev))
+ return -EOPNOTSUPP;
+
+ if (mvq->fw_state != MLX5_VIRTIO_NET_Q_OBJECT_STATE_RDY)
+ return -EAGAIN;
+
+ cmd_hdr = MLX5_ADDR_OF(query_virtio_q_counters_in, in, hdr);
+
+ MLX5_SET(general_obj_in_cmd_hdr, cmd_hdr, opcode, MLX5_CMD_OP_QUERY_GENERAL_OBJECT);
+ MLX5_SET(general_obj_in_cmd_hdr, cmd_hdr, obj_type, MLX5_OBJ_TYPE_VIRTIO_Q_COUNTERS);
+ MLX5_SET(general_obj_in_cmd_hdr, cmd_hdr, uid, ndev->mvdev.res.uid);
+ MLX5_SET(general_obj_in_cmd_hdr, cmd_hdr, obj_id, mvq->counter_set_id);
+
+ err = mlx5_cmd_exec(ndev->mvdev.mdev, in, sizeof(in), out, sizeof(out));
+ if (err)
+ return err;
+
+ ctx = MLX5_ADDR_OF(query_virtio_q_counters_out, out, counters);
+ *received_desc = MLX5_GET64(virtio_q_counters, ctx, received_desc);
+ *completed_desc = MLX5_GET64(virtio_q_counters, ctx, completed_desc);
+ return 0;
+}
+
+static int mlx5_vdpa_get_vendor_vq_stats(struct vdpa_device *vdev, u16 idx,
+ struct sk_buff *msg,
+ struct netlink_ext_ack *extack)
+{
+ struct mlx5_vdpa_dev *mvdev = to_mvdev(vdev);
+ struct mlx5_vdpa_net *ndev = to_mlx5_vdpa_ndev(mvdev);
+ struct mlx5_vdpa_virtqueue *mvq;
+ struct mlx5_control_vq *cvq;
+ u64 received_desc;
+ u64 completed_desc;
+ int err = 0;
+ u16 max_vqp;
+
+ mutex_lock(&ndev->numq_lock);
+ if (!is_index_valid(mvdev, idx)) {
+ NL_SET_ERR_MSG_MOD(extack, "virtqueue index is not valid");
+ err = -EINVAL;
+ goto out_err;
+ }
+
+ if (idx == ctrl_vq_idx(mvdev)) {
+ cvq = &mvdev->cvq;
+ received_desc = cvq->received_desc;
+ completed_desc = cvq->completed_desc;
+ goto out;
+ }
+
+ mvq = &ndev->vqs[idx];
+ err = counter_set_query(ndev, mvq, &received_desc, &completed_desc);
+ if (err) {
+ NL_SET_ERR_MSG_MOD(extack, "failed to query hardware");
+ goto out_err;
+ }
+
+out:
+ err = -EMSGSIZE;
+ if (nla_put_u64_64bit(msg, VDPA_ATTR_DEV_NEGOTIATED_FEATURES,
+ mvdev->actual_features, VDPA_ATTR_PAD))
+ goto out_err;
+
+ max_vqp = mlx5vdpa16_to_cpu(mvdev, ndev->config.max_virtqueue_pairs);
+ if (nla_put_u16(msg, VDPA_ATTR_DEV_NET_CFG_MAX_VQP, max_vqp))
+ goto out_err;
+
+ if (nla_put_string(msg, VDPA_ATTR_DEV_VENDOR_ATTR_NAME, "received_desc"))
+ goto out_err;
+
+ if (nla_put_u64_64bit(msg, VDPA_ATTR_DEV_VENDOR_ATTR_VALUE, received_desc,
+ VDPA_ATTR_PAD))
+ goto out_err;
+
+ if (nla_put_string(msg, VDPA_ATTR_DEV_VENDOR_ATTR_NAME, "completed_desc"))
+ goto out_err;
+
+ if (nla_put_u64_64bit(msg, VDPA_ATTR_DEV_VENDOR_ATTR_VALUE, completed_desc,
+ VDPA_ATTR_PAD))
+ goto out_err;
+
+ err = 0;
+out_err:
+ mutex_unlock(&ndev->numq_lock);
+ return err;
+}
+
static const struct vdpa_config_ops mlx5_vdpa_ops = {
.set_vq_address = mlx5_vdpa_set_vq_address,
.set_vq_num = mlx5_vdpa_set_vq_num,
@@ -2451,6 +2613,7 @@ static const struct vdpa_config_ops mlx5_vdpa_ops = {
.get_vq_ready = mlx5_vdpa_get_vq_ready,
.set_vq_state = mlx5_vdpa_set_vq_state,
.get_vq_state = mlx5_vdpa_get_vq_state,
+ .get_vendor_vq_stats = mlx5_vdpa_get_vendor_vq_stats,
.get_vq_notification = mlx5_get_vq_notification,
.get_vq_irq = mlx5_get_vq_irq,
.get_vq_align = mlx5_vdpa_get_vq_align,
@@ -2706,6 +2869,7 @@ static int mlx5_vdpa_dev_add(struct vdpa_mgmt_dev *v_mdev, const char *name,

init_mvqs(ndev);
mutex_init(&ndev->reslock);
+ mutex_init(&ndev->numq_lock);
config = &ndev->config;

if (add_config->mask & BIT_ULL(VDPA_ATTR_DEV_NET_CFG_MTU)) {
@@ -2788,6 +2952,7 @@ static int mlx5_vdpa_dev_add(struct vdpa_mgmt_dev *v_mdev, const char *name,
if (!is_zero_ether_addr(config->mac))
mlx5_mpfs_del_mac(pfmdev, config->mac);
err_mtu:
+ mutex_destroy(&ndev->numq_lock);
mutex_destroy(&ndev->reslock);
err_alloc:
put_device(&mvdev->vdev.dev);
diff --git a/include/linux/mlx5/mlx5_ifc.h b/include/linux/mlx5/mlx5_ifc.h
index 49a48d7709ac..1d193d9b6029 100644
--- a/include/linux/mlx5/mlx5_ifc.h
+++ b/include/linux/mlx5/mlx5_ifc.h
@@ -94,6 +94,7 @@ enum {
enum {
MLX5_OBJ_TYPE_GENEVE_TLV_OPT = 0x000b,
MLX5_OBJ_TYPE_VIRTIO_NET_Q = 0x000d,
+ MLX5_OBJ_TYPE_VIRTIO_Q_COUNTERS = 0x001c,
MLX5_OBJ_TYPE_MATCH_DEFINER = 0x0018,
MLX5_OBJ_TYPE_MKEY = 0xff01,
MLX5_OBJ_TYPE_QP = 0xff02,
diff --git a/include/linux/mlx5/mlx5_ifc_vdpa.h b/include/linux/mlx5/mlx5_ifc_vdpa.h
index 1a9c9d94cb59..4414ed5b6ed2 100644
--- a/include/linux/mlx5/mlx5_ifc_vdpa.h
+++ b/include/linux/mlx5/mlx5_ifc_vdpa.h
@@ -165,4 +165,43 @@ struct mlx5_ifc_modify_virtio_net_q_out_bits {
struct mlx5_ifc_general_obj_out_cmd_hdr_bits general_obj_out_cmd_hdr;
};

+struct mlx5_ifc_virtio_q_counters_bits {
+ u8 modify_field_select[0x40];
+ u8 reserved_at_40[0x40];
+ u8 received_desc[0x40];
+ u8 completed_desc[0x40];
+ u8 error_cqes[0x20];
+ u8 bad_desc_errors[0x20];
+ u8 exceed_max_chain[0x20];
+ u8 invalid_buffer[0x20];
+ u8 reserved_at_180[0x280];
+};
+
+struct mlx5_ifc_create_virtio_q_counters_in_bits {
+ struct mlx5_ifc_general_obj_in_cmd_hdr_bits hdr;
+ struct mlx5_ifc_virtio_q_counters_bits virtio_q_counters;
+};
+
+struct mlx5_ifc_create_virtio_q_counters_out_bits {
+ struct mlx5_ifc_general_obj_in_cmd_hdr_bits hdr;
+ struct mlx5_ifc_virtio_q_counters_bits virtio_q_counters;
+};
+
+struct mlx5_ifc_destroy_virtio_q_counters_in_bits {
+ struct mlx5_ifc_general_obj_in_cmd_hdr_bits hdr;
+};
+
+struct mlx5_ifc_destroy_virtio_q_counters_out_bits {
+ struct mlx5_ifc_general_obj_out_cmd_hdr_bits hdr;
+};
+
+struct mlx5_ifc_query_virtio_q_counters_in_bits {
+ struct mlx5_ifc_general_obj_in_cmd_hdr_bits hdr;
+};
+
+struct mlx5_ifc_query_virtio_q_counters_out_bits {
+ struct mlx5_ifc_general_obj_in_cmd_hdr_bits hdr;
+ struct mlx5_ifc_virtio_q_counters_bits counters;
+};
+
#endif /* __MLX5_IFC_VDPA_H_ */
--
2.35.1