net/mlx5: fix link status to use wait to complete

Wait to complete is present to let the application get a correct status
when it requires it, it should not be ignored.

Fixes: e313ef4c2fe8 ("net/mlx5: fix link state on device start")
Fixes: cb8faed7dde8 ("mlx5: support link status update")
Cc: stable@dpdk.org
Signed-off-by: Nelio Laranjeiro <nelio.laranjeiro@6wind.com>
Acked-by: Adrien Mazarguil <adrien.mazarguil@6wind.com>

diff --git a/drivers/net/mlx5/mlx5.h b/drivers/net/mlx5/mlx5.h
index 8631040..faacfd9 100644 (file)
--- a/drivers/net/mlx5/mlx5.h
+++ b/drivers/net/mlx5/mlx5.h
@@ -124,7 +124,6 @@ struct priv {
        /* Device properties. */
        uint16_t mtu; /* Configured MTU. */
        uint8_t port; /* Physical port number. */
-       unsigned int pending_alarm:1; /* An alarm is pending. */
        unsigned int isolated:1; /* Whether isolated mode is enabled. */
        /* RX/TX queues. */
        unsigned int rxqs_n; /* RX queues array size. */

diff --git a/drivers/net/mlx5/mlx5_defs.h b/drivers/net/mlx5/mlx5_defs.h
index c3334ca..6401588 100644 (file)
--- a/drivers/net/mlx5/mlx5_defs.h
+++ b/drivers/net/mlx5/mlx5_defs.h
@@ -82,8 +82,8 @@
 /* Supported RSS */
 #define MLX5_RSS_HF_MASK (~(ETH_RSS_IP | ETH_RSS_UDP | ETH_RSS_TCP))
 
-/* Maximum number of attempts to query link status before giving up. */
-#define MLX5_MAX_LINK_QUERY_ATTEMPTS 5
+/* Timeout in seconds to get a valid link status. */
+#define MLX5_LINK_STATUS_TIMEOUT 10
 
 /* Reserved address space for UAR mapping. */
 #define MLX5_UAR_SIZE (1ULL << 32)

diff --git a/drivers/net/mlx5/mlx5_ethdev.c b/drivers/net/mlx5/mlx5_ethdev.c
index 10ba27c..f5511ce 100644 (file)
--- a/drivers/net/mlx5/mlx5_ethdev.c
+++ b/drivers/net/mlx5/mlx5_ethdev.c
@@ -24,6 +24,7 @@
 #include <fcntl.h>
 #include <stdalign.h>
 #include <sys/un.h>
+#include <time.h>
 
 #include <rte_atomic.h>
 #include <rte_ethdev_driver.h>
@@ -31,7 +32,6 @@
 #include <rte_mbuf.h>
 #include <rte_common.h>
 #include <rte_interrupts.h>
-#include <rte_alarm.h>
 #include <rte_malloc.h>
 
 #include "mlx5.h"
@@ -473,12 +473,15 @@ mlx5_dev_supported_ptypes_get(struct rte_eth_dev *dev)
  *
  * @param dev
  *   Pointer to Ethernet device structure.
+ * @param[out] link
+ *   Storage for current link status.
  *
  * @return
  *   0 on success, a negative errno value otherwise and rte_errno is set.
  */
 static int
-mlx5_link_update_unlocked_gset(struct rte_eth_dev *dev)
+mlx5_link_update_unlocked_gset(struct rte_eth_dev *dev,
+                              struct rte_eth_link *link)
 {
        struct priv *priv = dev->data->dev_private;
        struct ethtool_cmd edata = {
@@ -528,14 +531,13 @@ mlx5_link_update_unlocked_gset(struct rte_eth_dev *dev)
                                ETH_LINK_HALF_DUPLEX : ETH_LINK_FULL_DUPLEX);
        dev_link.link_autoneg = !(dev->data->dev_conf.link_speeds &
                        ETH_LINK_SPEED_FIXED);
-       if (memcmp(&dev_link, &dev->data->dev_link, sizeof(dev_link))) {
-               /* Link status changed. */
-               dev->data->dev_link = dev_link;
-               return 0;
+       if ((dev_link.link_speed && !dev_link.link_status) ||
+           (!dev_link.link_speed && dev_link.link_status)) {
+               rte_errno = EAGAIN;
+               return -rte_errno;
        }
-       /* Link status is still the same. */
-       rte_errno = EAGAIN;
-       return -rte_errno;
+       *link = dev_link;
+       return 0;
 }
 
 /**
@@ -543,12 +545,16 @@ mlx5_link_update_unlocked_gset(struct rte_eth_dev *dev)
  *
  * @param dev
  *   Pointer to Ethernet device structure.
+ * @param[out] link
+ *   Storage for current link status.
  *
  * @return
  *   0 on success, a negative errno value otherwise and rte_errno is set.
  */
 static int
-mlx5_link_update_unlocked_gs(struct rte_eth_dev *dev)
+mlx5_link_update_unlocked_gs(struct rte_eth_dev *dev,
+                            struct rte_eth_link *link)
+
 {
        struct priv *priv = dev->data->dev_private;
        struct ethtool_link_settings gcmd = { .cmd = ETHTOOL_GLINKSETTINGS };
@@ -634,14 +640,13 @@ mlx5_link_update_unlocked_gs(struct rte_eth_dev *dev)
                                ETH_LINK_HALF_DUPLEX : ETH_LINK_FULL_DUPLEX);
        dev_link.link_autoneg = !(dev->data->dev_conf.link_speeds &
                                  ETH_LINK_SPEED_FIXED);
-       if (memcmp(&dev_link, &dev->data->dev_link, sizeof(dev_link))) {
-               /* Link status changed. */
-               dev->data->dev_link = dev_link;
-               return 0;
+       if ((dev_link.link_speed && !dev_link.link_status) ||
+           (!dev_link.link_speed && dev_link.link_status)) {
+               rte_errno = EAGAIN;
+               return -rte_errno;
        }
-       /* Link status is still the same. */
-       rte_errno = EAGAIN;
-       return -rte_errno;
+       *link = dev_link;
+       return 0;
 }
 
 /**
@@ -650,20 +655,43 @@ mlx5_link_update_unlocked_gs(struct rte_eth_dev *dev)
  * @param dev
  *   Pointer to Ethernet device structure.
  * @param wait_to_complete
- *   Wait for request completion (ignored).
+ *   Wait for request completion.
  *
  * @return
- *   0 on success, a negative errno value otherwise and rte_errno is set.
+ *   0 if link status was not updated, positive if it was, a negative errno
+ *   value otherwise and rte_errno is set.
  */
 int
-mlx5_link_update(struct rte_eth_dev *dev, int wait_to_complete __rte_unused)
+mlx5_link_update(struct rte_eth_dev *dev, int wait_to_complete)
 {
        int ret;
+       struct rte_eth_link dev_link;
+       time_t start_time = time(NULL);
 
-       ret = mlx5_link_update_unlocked_gset(dev);
-       if (ret)
-               ret = mlx5_link_update_unlocked_gs(dev);
-       return 0;
+       do {
+               ret = mlx5_link_update_unlocked_gset(dev, &dev_link);
+               if (ret)
+                       ret = mlx5_link_update_unlocked_gs(dev, &dev_link);
+               if (ret == 0)
+                       break;
+               /* Handle wait to complete situation. */
+               if (wait_to_complete && ret == -EAGAIN) {
+                       if (abs((int)difftime(time(NULL), start_time)) <
+                           MLX5_LINK_STATUS_TIMEOUT) {
+                               usleep(0);
+                               continue;
+                       } else {
+                               rte_errno = EBUSY;
+                               return -rte_errno;
+                       }
+               } else if (ret < 0) {
+                       return ret;
+               }
+       } while (wait_to_complete);
+       ret = !!memcmp(&dev->data->dev_link, &dev_link,
+                      sizeof(struct rte_eth_link));
+       dev->data->dev_link = dev_link;
+       return ret;
 }
 
 /**
@@ -841,47 +869,6 @@ mlx5_ibv_device_to_pci_addr(const struct ibv_device *device,
        return 0;
 }
 
-/**
- * Update the link status.
- *
- * @param dev
- *   Pointer to Ethernet device.
- *
- * @return
- *   Zero if the callback process can be called immediately, negative errno
- *   value otherwise and rte_errno is set.
- */
-static int
-mlx5_link_status_update(struct rte_eth_dev *dev)
-{
-       struct priv *priv = dev->data->dev_private;
-       struct rte_eth_link *link = &dev->data->dev_link;
-       int ret;
-
-       ret = mlx5_link_update(dev, 0);
-       if (ret)
-               return ret;
-       if (((link->link_speed == 0) && link->link_status) ||
-               ((link->link_speed != 0) && !link->link_status)) {
-               /*
-                * Inconsistent status. Event likely occurred before the
-                * kernel netdevice exposes the new status.
-                */
-               if (!priv->pending_alarm) {
-                       priv->pending_alarm = 1;
-                       rte_eal_alarm_set(MLX5_ALARM_TIMEOUT_US,
-                                         mlx5_dev_link_status_handler,
-                                         priv->dev);
-               }
-               return 1;
-       } else if (unlikely(priv->pending_alarm)) {
-               /* Link interrupt occurred while alarm is already scheduled. */
-               priv->pending_alarm = 0;
-               rte_eal_alarm_cancel(mlx5_dev_link_status_handler, priv->dev);
-       }
-       return 0;
-}
-
 /**
  * Device status handler.
  *
@@ -900,6 +887,10 @@ mlx5_dev_status_handler(struct rte_eth_dev *dev)
        struct ibv_async_event event;
        uint32_t ret = 0;
 
+       if (mlx5_link_update(dev, 0) == -EAGAIN) {
+               usleep(0);
+               return 0;
+       }
        /* Read all message and acknowledge them. */
        for (;;) {
                if (mlx5_glue->get_async_event(priv->ctx, &event))
@@ -917,31 +908,9 @@ mlx5_dev_status_handler(struct rte_eth_dev *dev)
                                dev->data->port_id, event.event_type);
                mlx5_glue->ack_async_event(&event);
        }
-       if (ret & (1 << RTE_ETH_EVENT_INTR_LSC))
-               if (mlx5_link_status_update(dev))
-                       ret &= ~(1 << RTE_ETH_EVENT_INTR_LSC);
        return ret;
 }
 
-/**
- * Handle delayed link status event.
- *
- * @param arg
- *   Registered argument.
- */
-void
-mlx5_dev_link_status_handler(void *arg)
-{
-       struct rte_eth_dev *dev = arg;
-       struct priv *priv = dev->data->dev_private;
-       int ret;
-
-       priv->pending_alarm = 0;
-       ret = mlx5_link_status_update(dev);
-       if (!ret)
-               _rte_eth_dev_callback_process(dev, RTE_ETH_EVENT_INTR_LSC, NULL);
-}
-
 /**
  * Handle interrupts from the NIC.
  *
@@ -995,10 +964,6 @@ mlx5_dev_interrupt_handler_uninstall(struct rte_eth_dev *dev)
        if (priv->primary_socket)
                rte_intr_callback_unregister(&priv->intr_handle_socket,
                                             mlx5_dev_handler_socket, dev);
-       if (priv->pending_alarm) {
-               priv->pending_alarm = 0;
-               rte_eal_alarm_cancel(mlx5_dev_link_status_handler, dev);
-       }
        priv->intr_handle.fd = 0;
        priv->intr_handle.type = RTE_INTR_HANDLE_UNKNOWN;
        priv->intr_handle_socket.fd = 0;