[dpdk-dev] [PATCH 3/3] vdpa/mlx5: add traffic control device arguments

[Matan Azrad <matan@mellanox.com>]

Add 2 device arguments to conrol traffic modes:
1. Control the CQ polling timer frequency when traffic is on.
2. Control the non-traffic time which moves the timer to be off.

Signed-off-by: Matan Azrad <matan@mellanox.com>
---
 doc/guides/vdpadevs/mlx5.rst        | 17 ++++++++++++++
 drivers/vdpa/mlx5/mlx5_vdpa.c       | 46 +++++++++++++++++++++++++++++++++++++
 drivers/vdpa/mlx5/mlx5_vdpa.h       |  1 +
 drivers/vdpa/mlx5/mlx5_vdpa_event.c |  6 +----
 4 files changed, 65 insertions(+), 5 deletions(-)

diff --git a/doc/guides/vdpadevs/mlx5.rst b/doc/guides/vdpadevs/mlx5.rst
index dd377af..05f26e0 100644
--- a/doc/guides/vdpadevs/mlx5.rst
+++ b/doc/guides/vdpadevs/mlx5.rst
@@ -106,8 +106,25 @@ Run-time configuration
 
 - **ethtool** operations on related kernel interfaces also affect the PMD.
 
+Driver options
+^^^^^^^^^^^^^^
+
 - ``class`` parameter [string]
 
   Select the class of the driver that should probe the device.
   `vdpa` for the mlx5 vDPA driver.
 
+- ``timer_delay`` parameter [int]
+
+  A nonzero value allows to configure the internal timer delay in micro-seconds.
+  The internal timer event causes polling of all the CQs, so this number may
+  affect the performance.
+  Default value is 500us.
+
+- ``no_traffic_time`` parameter [int]
+
+  A nonzero value defines the traffic off time, in seconds, that moves the
+  driver to no-traffic mode. In this mode the timer events are stopped and
+  interrupts are configured to the device in order to notify traffic for the
+  driver.
+  Default value is 2s.
diff --git a/drivers/vdpa/mlx5/mlx5_vdpa.c b/drivers/vdpa/mlx5/mlx5_vdpa.c
index 8b0b3b8..9e758b6 100644
--- a/drivers/vdpa/mlx5/mlx5_vdpa.c
+++ b/drivers/vdpa/mlx5/mlx5_vdpa.c
@@ -43,6 +43,8 @@
 
 #define MLX5_VDPA_MAX_RETRIES 20
 #define MLX5_VDPA_USEC 1000
+#define MLX5_VDPA_DEFAULT_TIMER_DELAY_US 500u
+#define MLX5_VDPA_DEFAULT_NO_TRAFFIC_TIME_S 2LLU
 
 TAILQ_HEAD(mlx5_vdpa_privs, mlx5_vdpa_priv) priv_list =
 					      TAILQ_HEAD_INITIALIZER(priv_list);
@@ -605,6 +607,49 @@
 	return -rte_errno;
 }
 
+static int
+mlx5_vdpa_args_check_handler(const char *key, const char *val, void *opaque)
+{
+	struct mlx5_vdpa_priv *priv = opaque;
+	unsigned long tmp;
+
+	if (strcmp(key, "class") == 0)
+		return 0;
+	errno = 0;
+	tmp = strtoul(val, NULL, 0);
+	if (errno) {
+		DRV_LOG(WARNING, "%s: \"%s\" is an invalid integer.", key, val);
+		return -errno;
+	}
+	if (strcmp(key, "timer_delay") == 0) {
+		priv->timer_delay_us = (uint32_t)tmp;
+	} else if (strcmp(key, "no_traffic_time") == 0) {
+		priv->no_traffic_time_s = (uint32_t)tmp;
+	} else {
+		DRV_LOG(WARNING, "Invalid key %s.", key);
+		return -EINVAL;
+	}
+	return 0;
+}
+
+static void
+mlx5_vdpa_config_get(struct rte_devargs *devargs, struct mlx5_vdpa_priv *priv)
+{
+	struct rte_kvargs *kvlist;
+
+	priv->timer_delay_us = MLX5_VDPA_DEFAULT_TIMER_DELAY_US;
+	priv->no_traffic_time_s = MLX5_VDPA_DEFAULT_NO_TRAFFIC_TIME_S;
+	if (devargs == NULL)
+		return;
+	kvlist = rte_kvargs_parse(devargs->args, NULL);
+	if (kvlist == NULL)
+		return;
+	rte_kvargs_process(kvlist, NULL, mlx5_vdpa_args_check_handler, priv);
+	rte_kvargs_free(kvlist);
+	DRV_LOG(DEBUG, "timer delay is %u us.", priv->timer_delay_us);
+	DRV_LOG(DEBUG, "no traffic time is %u s.", priv->no_traffic_time_s);
+}
+
 /**
  * DPDK callback to register a PCI device.
  *
@@ -694,6 +739,7 @@
 		rte_errno = rte_errno ? rte_errno : EINVAL;
 		goto error;
 	}
+	mlx5_vdpa_config_get(pci_dev->device.devargs, priv);
 	SLIST_INIT(&priv->mr_list);
 	pthread_mutex_lock(&priv_list_lock);
 	TAILQ_INSERT_TAIL(&priv_list, priv, next);
diff --git a/drivers/vdpa/mlx5/mlx5_vdpa.h b/drivers/vdpa/mlx5/mlx5_vdpa.h
index ae1dcd8..28ec0be 100644
--- a/drivers/vdpa/mlx5/mlx5_vdpa.h
+++ b/drivers/vdpa/mlx5/mlx5_vdpa.h
@@ -110,6 +110,7 @@ struct mlx5_vdpa_priv {
 	pthread_cond_t timer_cond;
 	volatile uint8_t timer_on;
 	uint32_t timer_delay_us;
+	uint32_t no_traffic_time_s;
 	int id; /* vDPA device id. */
 	int vid; /* vhost device id. */
 	struct ibv_context *ctx; /* Device context. */
diff --git a/drivers/vdpa/mlx5/mlx5_vdpa_event.c b/drivers/vdpa/mlx5/mlx5_vdpa_event.c
index 25f11fd..06a373a 100644
--- a/drivers/vdpa/mlx5/mlx5_vdpa_event.c
+++ b/drivers/vdpa/mlx5/mlx5_vdpa_event.c
@@ -20,9 +20,6 @@
 #include "mlx5_vdpa.h"
 
 
-#define MLX5_VDPA_DEFAULT_TIMER_DELAY_US 500u
-#define MLX5_VDPA_NO_TRAFFIC_TIME_S 2LLU
-
 void
 mlx5_vdpa_event_qp_global_release(struct mlx5_vdpa_priv *priv)
 {
@@ -286,7 +283,7 @@
 		if (!total) {
 			/* No traffic ? stop timer and load interrupts. */
 			if (current_tic - priv->last_traffic_tic >=
-			    rte_get_timer_hz() * MLX5_VDPA_NO_TRAFFIC_TIME_S) {
+			    rte_get_timer_hz() * priv->no_traffic_time_s) {
 				DRV_LOG(DEBUG, "Device %d traffic was stopped.",
 					priv->id);
 				mlx5_vdpa_arm_all_cqs(priv);
@@ -358,7 +355,6 @@
 	pthread_mutex_init(&priv->timer_lock, NULL);
 	pthread_cond_init(&priv->timer_cond, NULL);
 	priv->timer_on = 0;
-	priv->timer_delay_us = MLX5_VDPA_DEFAULT_TIMER_DELAY_US;
 	ret = pthread_create(&priv->timer_tid, NULL, mlx5_vdpa_poll_handle,
 			     (void *)priv);
 	if (ret) {
-- 
1.8.3.1