[PATCH net-next V3 0/3] Add max rate TXQ attribute

[PATCH net-next V3 0/3] Add max rate TXQ attribute

[Or Gerlitz]

Add the ability to set a max-rate limitation for TX queues.
The attribute name is maxrate and the units are Mbs, to make
it similar to the existing max-rate limitation knobs (ETS and 
SRIOV ndo calls).

Or.

changes from V2:
  - added Documentation (thanks Florian and Tom)
  - rebased to latest net-next to comply with the swdev ndo removal 
  - addressed more feedback from Dave on the comments style

changes from V1:
  - addressed feedback from Dave 

changes from V0:
  - addressed feedback from Sergei


John Fastabend (1):
  net: Add max rate tx queue attribute

Or Gerlitz (2):
  net/mlx4_core: Add basic support for QP max-rate limiting
  net/mlx4_en: Add tx queue maxrate support

 Documentation/ABI/testing/sysfs-class-net-queues   |    8 +++
 Documentation/networking/scaling.txt               |    9 +++
 drivers/net/ethernet/mellanox/mlx4/en_netdev.c     |   29 +++++++++
 drivers/net/ethernet/mellanox/mlx4/fw.c            |   33 +++++++++-
 drivers/net/ethernet/mellanox/mlx4/fw.h            |    1 +
 drivers/net/ethernet/mellanox/mlx4/main.c          |    2 +
 drivers/net/ethernet/mellanox/mlx4/qp.c            |    5 ++
 .../net/ethernet/mellanox/mlx4/resource_tracker.c  |    6 ++-
 include/linux/mlx4/device.h                        |   17 +++++
 include/linux/mlx4/qp.h                            |   14 +++-
 include/linux/netdevice.h                          |    8 +++
 net/core/net-sysfs.c                               |   67 ++++++++++++++++----
 12 files changed, 181 insertions(+), 18 deletions(-)

[PATCH net-next V3 1/3] net: Add max rate tx queue attribute

[Or Gerlitz]

From: John Fastabend <john.r.fastabend@intel.com>

This adds a tx_maxrate attribute to the tx queue sysfs entry allowing
for max-rate limiting. Along with DCB-ETS and BQL this provides another
knob to tune queue performance. The limit units are Mbps.

By default it is disabled. To disable the rate limitation after it
has been set for a queue, it should be set to zero.

Signed-off-by: John Fastabend <john.r.fastabend@intel.com>
Signed-off-by: Or Gerlitz <ogerlitz@mellanox.com>
---
 Documentation/ABI/testing/sysfs-class-net-queues |    8 +++
 Documentation/networking/scaling.txt             |    9 +++
 include/linux/netdevice.h                        |    8 +++
 net/core/net-sysfs.c                             |   67 ++++++++++++++++++----
 4 files changed, 80 insertions(+), 12 deletions(-)

diff --git a/Documentation/ABI/testing/sysfs-class-net-queues b/Documentation/ABI/testing/sysfs-class-net-queues
index 5e9aeb9..0c0df91 100644
--- a/Documentation/ABI/testing/sysfs-class-net-queues
+++ b/Documentation/ABI/testing/sysfs-class-net-queues
@@ -24,6 +24,14 @@ Description:
 		Indicates the number of transmit timeout events seen by this
 		network interface transmit queue.
 
+What:		/sys/class/<iface>/queues/tx-<queue>/tx_maxrate
+Date:		March 2015
+KernelVersion:	4.1
+Contact:	netdev@vger.kernel.org
+Description:
+		A Mbps max-rate set for the queue, a value of zero means disabled,
+		default is disabled.
+
 What:		/sys/class/<iface>/queues/tx-<queue>/xps_cpus
 Date:		November 2010
 KernelVersion:	2.6.38
diff --git a/Documentation/networking/scaling.txt b/Documentation/networking/scaling.txt
index 99ca40e..cbfac09 100644
--- a/Documentation/networking/scaling.txt
+++ b/Documentation/networking/scaling.txt
@@ -421,6 +421,15 @@ best CPUs to share a given queue are probably those that share the cache
 with the CPU that processes transmit completions for that queue
 (transmit interrupts).
 
+Per TX Queue rate limitation:
+=============================
+
+These are rate-limitation mechanisms implemented by HW, where currently
+a max-rate attribute is supported, by setting a Mbps value to
+
+/sys/class/net/<dev>/queues/tx-<n>/tx_maxrate
+
+A value of zero means disabled, and this is the default.
 
 Further Information
 ===================
diff --git a/include/linux/netdevice.h b/include/linux/netdevice.h
index dd1d069..76c5de4 100644
--- a/include/linux/netdevice.h
+++ b/include/linux/netdevice.h
@@ -587,6 +587,7 @@ struct netdev_queue {
 #ifdef CONFIG_BQL
 	struct dql		dql;
 #endif
+	unsigned long		tx_maxrate;
 } ____cacheline_aligned_in_smp;
 
 static inline int netdev_queue_numa_node_read(const struct netdev_queue *q)
@@ -1022,6 +1023,10 @@ typedef u16 (*select_queue_fallback_t)(struct net_device *dev,
  *	be otherwise expressed by feature flags. The check is called with
  *	the set of features that the stack has calculated and it returns
  *	those the driver believes to be appropriate.
+ * int (*ndo_set_tx_maxrate)(struct net_device *dev,
+ *			     int queue_index, u32 maxrate);
+ *	Called when a user wants to set a max-rate limitation of specific
+ *	TX queue.
  */
 struct net_device_ops {
 	int			(*ndo_init)(struct net_device *dev);
@@ -1178,6 +1183,9 @@ struct net_device_ops {
 	netdev_features_t	(*ndo_features_check) (struct sk_buff *skb,
 						       struct net_device *dev,
 						       netdev_features_t features);
+	int			(*ndo_set_tx_maxrate)(struct net_device *dev,
+						      int queue_index,
+						      u32 maxrate);
 };
 
 /**
diff --git a/net/core/net-sysfs.c b/net/core/net-sysfs.c
index cf30620..7e58bd7 100644
--- a/net/core/net-sysfs.c
+++ b/net/core/net-sysfs.c
@@ -951,6 +951,60 @@ static ssize_t show_trans_timeout(struct netdev_queue *queue,
 	return sprintf(buf, "%lu", trans_timeout);
 }
 
+#ifdef CONFIG_XPS
+static inline unsigned int get_netdev_queue_index(struct netdev_queue *queue)
+{
+	struct net_device *dev = queue->dev;
+	int i;
+
+	for (i = 0; i < dev->num_tx_queues; i++)
+		if (queue == &dev->_tx[i])
+			break;
+
+	BUG_ON(i >= dev->num_tx_queues);
+
+	return i;
+}
+
+static ssize_t show_tx_maxrate(struct netdev_queue *queue,
+			       struct netdev_queue_attribute *attribute,
+			       char *buf)
+{
+	return sprintf(buf, "%lu\n", queue->tx_maxrate);
+}
+
+static ssize_t set_tx_maxrate(struct netdev_queue *queue,
+			      struct netdev_queue_attribute *attribute,
+			      const char *buf, size_t len)
+{
+	struct net_device *dev = queue->dev;
+	int err, index = get_netdev_queue_index(queue);
+	u32 rate = 0;
+
+	err = kstrtou32(buf, 10, &rate);
+	if (err < 0)
+		return err;
+
+	if (!rtnl_trylock())
+		return restart_syscall();
+
+	err = -EOPNOTSUPP;
+	if (dev->netdev_ops->ndo_set_tx_maxrate)
+		err = dev->netdev_ops->ndo_set_tx_maxrate(dev, index, rate);
+
+	rtnl_unlock();
+	if (!err) {
+		queue->tx_maxrate = rate;
+		return len;
+	}
+	return err;
+}
+
+static struct netdev_queue_attribute queue_tx_maxrate =
+	__ATTR(tx_maxrate, S_IRUGO | S_IWUSR,
+	       show_tx_maxrate, set_tx_maxrate);
+#endif
+
 static struct netdev_queue_attribute queue_trans_timeout =
 	__ATTR(tx_timeout, S_IRUGO, show_trans_timeout, NULL);
 
@@ -1065,18 +1119,6 @@ static struct attribute_group dql_group = {
 #endif /* CONFIG_BQL */
 
 #ifdef CONFIG_XPS
-static unsigned int get_netdev_queue_index(struct netdev_queue *queue)
-{
-	struct net_device *dev = queue->dev;
-	unsigned int i;
-
-	i = queue - dev->_tx;
-	BUG_ON(i >= dev->num_tx_queues);
-
-	return i;
-}
-
-
 static ssize_t show_xps_map(struct netdev_queue *queue,
 			    struct netdev_queue_attribute *attribute, char *buf)
 {
@@ -1153,6 +1195,7 @@ static struct attribute *netdev_queue_default_attrs[] = {
 	&queue_trans_timeout.attr,
 #ifdef CONFIG_XPS
 	&xps_cpus_attribute.attr,
+	&queue_tx_maxrate.attr,
 #endif
 	NULL
 };
-- 
1.7.1

[PATCH net-next V3 2/3] net/mlx4_core: Add basic support for QP max-rate limiting

[Or Gerlitz]

Add the low-level device commands and definitions used for QP max-rate limiting.

This is done through the following elements:

  - read rate-limit device caps in QUERY_DEV_CAP: number of different
    rates and the min/max rates in Kbs/Mbs/Gbs units

  - enhance the QP context struct to contain rate limit units and value

  - allow to do run time rate-limit setting to QPs through the
    update-qp firmware command

  - QP rate-limiting is disallowed for VFs

Signed-off-by: Or Gerlitz <ogerlitz@mellanox.com>
---
 drivers/net/ethernet/mellanox/mlx4/fw.c            |   33 +++++++++++++++++++-
 drivers/net/ethernet/mellanox/mlx4/fw.h            |    1 +
 drivers/net/ethernet/mellanox/mlx4/main.c          |    2 +
 drivers/net/ethernet/mellanox/mlx4/qp.c            |    5 +++
 .../net/ethernet/mellanox/mlx4/resource_tracker.c  |    6 +++-
 include/linux/mlx4/device.h                        |   17 ++++++++++
 include/linux/mlx4/qp.h                            |   14 ++++++--
 7 files changed, 72 insertions(+), 6 deletions(-)

diff --git a/drivers/net/ethernet/mellanox/mlx4/fw.c b/drivers/net/ethernet/mellanox/mlx4/fw.c
index 242bcee..4a471f5 100644
--- a/drivers/net/ethernet/mellanox/mlx4/fw.c
+++ b/drivers/net/ethernet/mellanox/mlx4/fw.c
@@ -144,7 +144,8 @@ static void dump_dev_cap_flags2(struct mlx4_dev *dev, u64 flags)
 		[19] = "Performance optimized for limited rule configuration flow steering support",
 		[20] = "Recoverable error events support",
 		[21] = "Port Remap support",
-		[22] = "QCN support"
+		[22] = "QCN support",
+		[23] = "QP rate limiting support"
 	};
 	int i;
 
@@ -697,6 +698,10 @@ int mlx4_QUERY_DEV_CAP(struct mlx4_dev *dev, struct mlx4_dev_cap *dev_cap)
 #define QUERY_DEV_CAP_MAD_DEMUX_OFFSET		0xb0
 #define QUERY_DEV_CAP_DMFS_HIGH_RATE_QPN_BASE_OFFSET	0xa8
 #define QUERY_DEV_CAP_DMFS_HIGH_RATE_QPN_RANGE_OFFSET	0xac
+#define QUERY_DEV_CAP_QP_RATE_LIMIT_NUM_OFFSET	0xcc
+#define QUERY_DEV_CAP_QP_RATE_LIMIT_MAX_OFFSET	0xd0
+#define QUERY_DEV_CAP_QP_RATE_LIMIT_MIN_OFFSET	0xd2
+
 
 	dev_cap->flags2 = 0;
 	mailbox = mlx4_alloc_cmd_mailbox(dev);
@@ -904,6 +909,18 @@ int mlx4_QUERY_DEV_CAP(struct mlx4_dev *dev, struct mlx4_dev_cap *dev_cap)
 		 QUERY_DEV_CAP_DMFS_HIGH_RATE_QPN_RANGE_OFFSET);
 	dev_cap->dmfs_high_rate_qpn_range &= MGM_QPN_MASK;
 
+	MLX4_GET(size, outbox, QUERY_DEV_CAP_QP_RATE_LIMIT_NUM_OFFSET);
+	dev_cap->rl_caps.num_rates = size;
+	if (dev_cap->rl_caps.num_rates) {
+		dev_cap->flags2 |= MLX4_DEV_CAP_FLAG2_QP_RATE_LIMIT;
+		MLX4_GET(size, outbox, QUERY_DEV_CAP_QP_RATE_LIMIT_MAX_OFFSET);
+		dev_cap->rl_caps.max_val  = size & 0xfff;
+		dev_cap->rl_caps.max_unit = size >> 14;
+		MLX4_GET(size, outbox, QUERY_DEV_CAP_QP_RATE_LIMIT_MIN_OFFSET);
+		dev_cap->rl_caps.min_val  = size & 0xfff;
+		dev_cap->rl_caps.min_unit = size >> 14;
+	}
+
 	MLX4_GET(field32, outbox, QUERY_DEV_CAP_EXT_2_FLAGS_OFFSET);
 	if (field32 & (1 << 16))
 		dev_cap->flags2 |= MLX4_DEV_CAP_FLAG2_UPDATE_QP;
@@ -979,6 +996,15 @@ void mlx4_dev_cap_dump(struct mlx4_dev *dev, struct mlx4_dev_cap *dev_cap)
 		 dev_cap->dmfs_high_rate_qpn_base);
 	mlx4_dbg(dev, "DMFS high rate steer QPn range: %d\n",
 		 dev_cap->dmfs_high_rate_qpn_range);
+
+	if (dev_cap->flags2 & MLX4_DEV_CAP_FLAG2_QP_RATE_LIMIT) {
+		struct mlx4_rate_limit_caps *rl_caps = &dev_cap->rl_caps;
+
+		mlx4_dbg(dev, "QP Rate-Limit: #rates %d, unit/val max %d/%d, min %d/%d\n",
+			 rl_caps->num_rates, rl_caps->max_unit, rl_caps->max_val,
+			 rl_caps->min_unit, rl_caps->min_val);
+	}
+
 	dump_dev_cap_flags(dev, dev_cap->flags);
 	dump_dev_cap_flags2(dev, dev_cap->flags2);
 }
@@ -1075,6 +1101,7 @@ int mlx4_QUERY_DEV_CAP_wrapper(struct mlx4_dev *dev, int slave,
 	u64	flags;
 	int	err = 0;
 	u8	field;
+	u16	field16;
 	u32	bmme_flags, field32;
 	int	real_port;
 	int	slave_port;
@@ -1158,6 +1185,10 @@ int mlx4_QUERY_DEV_CAP_wrapper(struct mlx4_dev *dev, int slave,
 	field &= 0xfe;
 	MLX4_PUT(outbox->buf, field, QUERY_DEV_CAP_ECN_QCN_VER_OFFSET);
 
+	/* turn off QP max-rate limiting for guests */
+	field16 = 0;
+	MLX4_PUT(outbox->buf, field16, QUERY_DEV_CAP_QP_RATE_LIMIT_NUM_OFFSET);
+
 	return 0;
 }
 
diff --git a/drivers/net/ethernet/mellanox/mlx4/fw.h b/drivers/net/ethernet/mellanox/mlx4/fw.h
index f44f7f6..863655b 100644
--- a/drivers/net/ethernet/mellanox/mlx4/fw.h
+++ b/drivers/net/ethernet/mellanox/mlx4/fw.h
@@ -127,6 +127,7 @@ struct mlx4_dev_cap {
 	u32 max_counters;
 	u32 dmfs_high_rate_qpn_base;
 	u32 dmfs_high_rate_qpn_range;
+	struct mlx4_rate_limit_caps rl_caps;
 	struct mlx4_port_cap port_cap[MLX4_MAX_PORTS + 1];
 };
 
diff --git a/drivers/net/ethernet/mellanox/mlx4/main.c b/drivers/net/ethernet/mellanox/mlx4/main.c
index 7e48722..43aa767 100644
--- a/drivers/net/ethernet/mellanox/mlx4/main.c
+++ b/drivers/net/ethernet/mellanox/mlx4/main.c
@@ -489,6 +489,8 @@ static int mlx4_dev_cap(struct mlx4_dev *dev, struct mlx4_dev_cap *dev_cap)
 		dev->caps.dmfs_high_rate_qpn_range = MLX4_A0_STEERING_TABLE_SIZE;
 	}
 
+	dev->caps.rl_caps = dev_cap->rl_caps;
+
 	dev->caps.reserved_qps_cnt[MLX4_QP_REGION_RSS_RAW_ETH] =
 		dev->caps.dmfs_high_rate_qpn_range;
 
diff --git a/drivers/net/ethernet/mellanox/mlx4/qp.c b/drivers/net/ethernet/mellanox/mlx4/qp.c
index eda29db..69e4462 100644
--- a/drivers/net/ethernet/mellanox/mlx4/qp.c
+++ b/drivers/net/ethernet/mellanox/mlx4/qp.c
@@ -442,6 +442,11 @@ int mlx4_update_qp(struct mlx4_dev *dev, u32 qpn,
 			cmd->qp_context.param3 |= cpu_to_be32(MLX4_STRIP_VLAN);
 	}
 
+	if (attr & MLX4_UPDATE_QP_RATE_LIMIT) {
+		qp_mask |= 1ULL << MLX4_UPD_QP_MASK_RATE_LIMIT;
+		cmd->qp_context.rate_limit_params = cpu_to_be16((params->rate_unit << 14) | params->rate_val);
+	}
+
 	cmd->primary_addr_path_mask = cpu_to_be64(pri_addr_path_mask);
 	cmd->qp_mask = cpu_to_be64(qp_mask);
 
diff --git a/drivers/net/ethernet/mellanox/mlx4/resource_tracker.c b/drivers/net/ethernet/mellanox/mlx4/resource_tracker.c
index d43e259..c258f86 100644
--- a/drivers/net/ethernet/mellanox/mlx4/resource_tracker.c
+++ b/drivers/net/ethernet/mellanox/mlx4/resource_tracker.c
@@ -2947,8 +2947,12 @@ static int verify_qp_parameters(struct mlx4_dev *dev,
 	qp_type	= (be32_to_cpu(qp_ctx->flags) >> 16) & 0xff;
 	optpar	= be32_to_cpu(*(__be32 *) inbox->buf);
 
-	if (slave != mlx4_master_func_num(dev))
+	if (slave != mlx4_master_func_num(dev)) {
 		qp_ctx->params2 &= ~MLX4_QP_BIT_FPP;
+		/* setting QP rate-limit is disallowed for VFs */
+		if (qp_ctx->rate_limit_params)
+			return -EPERM;
+	}
 
 	switch (qp_type) {
 	case MLX4_QP_ST_RC:
diff --git a/include/linux/mlx4/device.h b/include/linux/mlx4/device.h
index 1cc5482..4550c67 100644
--- a/include/linux/mlx4/device.h
+++ b/include/linux/mlx4/device.h
@@ -205,6 +205,7 @@ enum {
 	MLX4_DEV_CAP_FLAG2_RECOVERABLE_ERROR_EVENT = 1LL << 20,
 	MLX4_DEV_CAP_FLAG2_PORT_REMAP		= 1LL <<  21,
 	MLX4_DEV_CAP_FLAG2_QCN			= 1LL <<  22,
+	MLX4_DEV_CAP_FLAG2_QP_RATE_LIMIT	= 1LL <<  23
 };
 
 enum {
@@ -450,6 +451,21 @@ enum mlx4_module_id {
 	MLX4_MODULE_ID_QSFP28           = 0x11,
 };
 
+enum { /* rl */
+	MLX4_QP_RATE_LIMIT_NONE		= 0,
+	MLX4_QP_RATE_LIMIT_KBS		= 1,
+	MLX4_QP_RATE_LIMIT_MBS		= 2,
+	MLX4_QP_RATE_LIMIT_GBS		= 3
+};
+
+struct mlx4_rate_limit_caps {
+	u16	num_rates; /* Number of different rates */
+	u8	min_unit;
+	u16	min_val;
+	u8	max_unit;
+	u16	max_val;
+};
+
 static inline u64 mlx4_fw_ver(u64 major, u64 minor, u64 subminor)
 {
 	return (major << 32) | (minor << 16) | subminor;
@@ -565,6 +581,7 @@ struct mlx4_caps {
 	u32			dmfs_high_rate_qpn_base;
 	u32			dmfs_high_rate_qpn_range;
 	u32			vf_caps;
+	struct mlx4_rate_limit_caps rl_caps;
 };
 
 struct mlx4_buf_list {
diff --git a/include/linux/mlx4/qp.h b/include/linux/mlx4/qp.h
index 551f854..1023ebe 100644
--- a/include/linux/mlx4/qp.h
+++ b/include/linux/mlx4/qp.h
@@ -207,14 +207,16 @@ struct mlx4_qp_context {
 	__be32			msn;
 	__be16			rq_wqe_counter;
 	__be16			sq_wqe_counter;
-	u32			reserved3[2];
+	u32			reserved3;
+	__be16			rate_limit_params;
+	__be16			reserved4;
 	__be32			param3;
 	__be32			nummmcpeers_basemkey;
 	u8			log_page_size;
-	u8			reserved4[2];
+	u8			reserved5[2];
 	u8			mtt_base_addr_h;
 	__be32			mtt_base_addr_l;
-	u32			reserved5[10];
+	u32			reserved6[10];
 };
 
 struct mlx4_update_qp_context {
@@ -229,6 +231,7 @@ struct mlx4_update_qp_context {
 enum {
 	MLX4_UPD_QP_MASK_PM_STATE	= 32,
 	MLX4_UPD_QP_MASK_VSD		= 33,
+	MLX4_UPD_QP_MASK_RATE_LIMIT	= 35,
 };
 
 enum {
@@ -428,7 +431,8 @@ struct mlx4_wqe_inline_seg {
 enum mlx4_update_qp_attr {
 	MLX4_UPDATE_QP_SMAC		= 1 << 0,
 	MLX4_UPDATE_QP_VSD		= 1 << 1,
-	MLX4_UPDATE_QP_SUPPORTED_ATTRS	= (1 << 2) - 1
+	MLX4_UPDATE_QP_RATE_LIMIT	= 1 << 2,
+	MLX4_UPDATE_QP_SUPPORTED_ATTRS	= (1 << 3) - 1
 };
 
 enum mlx4_update_qp_params_flags {
@@ -438,6 +442,8 @@ enum mlx4_update_qp_params_flags {
 struct mlx4_update_qp_params {
 	u8	smac_index;
 	u32	flags;
+	u16	rate_unit;
+	u16	rate_val;
 };
 
 int mlx4_update_qp(struct mlx4_dev *dev, u32 qpn,
-- 
1.7.1

[PATCH net-next V3 3/3] net/mlx4_en: Add tx queue maxrate support

[Or Gerlitz]

Add ndo_set_tx_maxrate support.

To support per tx queue maxrate limit, we use the update-qp firmware
command to do run-time rate setting for the qp that serves this tx ring.

Signed-off-by: Or Gerlitz <ogerlitz@mellanox.com>
Signed-off-by: Ido Shamay <idos@mellanox.com>
---
 drivers/net/ethernet/mellanox/mlx4/en_netdev.c |   29 ++++++++++++++++++++++++
 1 files changed, 29 insertions(+), 0 deletions(-)

diff --git a/drivers/net/ethernet/mellanox/mlx4/en_netdev.c b/drivers/net/ethernet/mellanox/mlx4/en_netdev.c
index c59ed92..d8dc3f9 100644
--- a/drivers/net/ethernet/mellanox/mlx4/en_netdev.c
+++ b/drivers/net/ethernet/mellanox/mlx4/en_netdev.c
@@ -2379,6 +2379,33 @@ static netdev_features_t mlx4_en_features_check(struct sk_buff *skb,
 }
 #endif
 
+int mlx4_en_set_tx_maxrate(struct net_device *dev, int queue_index, u32 maxrate)
+{
+	struct mlx4_en_priv *priv = netdev_priv(dev);
+	struct mlx4_en_tx_ring *tx_ring = priv->tx_ring[queue_index];
+	struct mlx4_update_qp_params params;
+	int err;
+
+	if (!(priv->mdev->dev->caps.flags2 & MLX4_DEV_CAP_FLAG2_QP_RATE_LIMIT))
+		return -EOPNOTSUPP;
+
+	/* rate provided to us in Mbs, check if it fits into 12 bits, if not use Gbs */
+	if (maxrate >> 12) {
+		params.rate_unit = MLX4_QP_RATE_LIMIT_GBS;
+		params.rate_val  = maxrate / 1000;
+	} else if (maxrate) {
+		params.rate_unit = MLX4_QP_RATE_LIMIT_MBS;
+		params.rate_val  = maxrate;
+	} else { /* zero serves to revoke the QP rate-limitation */
+		params.rate_unit = 0;
+		params.rate_val  = 0;
+	}
+
+	err = mlx4_update_qp(priv->mdev->dev, tx_ring->qpn, MLX4_UPDATE_QP_RATE_LIMIT,
+			     &params);
+	return err;
+}
+
 static const struct net_device_ops mlx4_netdev_ops = {
 	.ndo_open		= mlx4_en_open,
 	.ndo_stop		= mlx4_en_close,
@@ -2410,6 +2437,7 @@ static const struct net_device_ops mlx4_netdev_ops = {
 	.ndo_del_vxlan_port	= mlx4_en_del_vxlan_port,
 	.ndo_features_check	= mlx4_en_features_check,
 #endif
+	.ndo_set_tx_maxrate	= mlx4_en_set_tx_maxrate,
 };
 
 static const struct net_device_ops mlx4_netdev_ops_master = {
@@ -2444,6 +2472,7 @@ static const struct net_device_ops mlx4_netdev_ops_master = {
 	.ndo_del_vxlan_port	= mlx4_en_del_vxlan_port,
 	.ndo_features_check	= mlx4_en_features_check,
 #endif
+	.ndo_set_tx_maxrate	= mlx4_en_set_tx_maxrate,
 };
 
 struct mlx4_en_bond {
-- 
1.7.1

Re: [PATCH net-next V3 0/3] Add max rate TXQ attribute

[David Miller]

From: Or Gerlitz <ogerlitz@mellanox.com>
Date: Wed, 18 Mar 2015 14:57:32 +0200

> Add the ability to set a max-rate limitation for TX queues.
> The attribute name is maxrate and the units are Mbs, to make
> it similar to the existing max-rate limitation knobs (ETS and 
> SRIOV ndo calls).

Series applied, thanks.