net/mlx5: allow multiple probing for representor

Implement probing of a rte device multiple times, see [1].
Set PCI driver RTE_PCI_DRV_PROBE_AGAIN flag to enable multiple probing
of the PCI device by the PCI common driver.
Consecutive probing requests with a devargs string may contain
repetitive master and representors devices for which eth device should
be created only once. In case an eth device already exists - silently
ignore it.

[1]
commit e9d159c3d534 ("eal: allow probing a device again")

Signed-off-by: Ophir Munk <ophirmu@mellanox.com>
Acked-by: Shahaf Shuler <shahafs@mellanox.com>

diff --git a/drivers/net/mlx5/mlx5.c b/drivers/net/mlx5/mlx5.c
index 410c0c3..1e976d7 100644 (file)
--- a/drivers/net/mlx5/mlx5.c
+++ b/drivers/net/mlx5/mlx5.c
@@ -694,9 +694,10 @@ mlx5_uar_init_secondary(struct rte_eth_dev *dev)
  *
  * @return
  *   A valid Ethernet device object on success, NULL otherwise and rte_errno
- *   is set. The following error is defined:
+ *   is set. The following errors are defined:
  *
  *   EBUSY: device is not supposed to be spawned.
+ *   EEXIST: device is already spawned
  */
 static struct rte_eth_dev *
 mlx5_dev_spawn(struct rte_device *dpdk_dev,
@@ -742,6 +743,7 @@ mlx5_dev_spawn(struct rte_device *dpdk_dev,
        struct ether_addr mac;
        char name[RTE_ETH_NAME_MAX_LEN];
        int own_domain_id = 0;
+       uint16_t port_id;
        unsigned int i;
 
        /* Determine if this port representor is supposed to be spawned. */
@@ -764,6 +766,17 @@ mlx5_dev_spawn(struct rte_device *dpdk_dev,
                        return NULL;
                }
        }
+       /* Build device name. */
+       if (!switch_info->representor)
+               rte_strlcpy(name, dpdk_dev->name, sizeof(name));
+       else
+               snprintf(name, sizeof(name), "%s_representor_%u",
+                        dpdk_dev->name, switch_info->port_name);
+       /* check if the device is already spawned */
+       if (rte_eth_dev_get_port_by_name(name, &port_id) == 0) {
+               rte_errno = EEXIST;
+               return NULL;
+       }
        /* Prepare shared data between primary and secondary process. */
        mlx5_prepare_shared_data();
        errno = 0;
@@ -870,11 +883,6 @@ mlx5_dev_spawn(struct rte_device *dpdk_dev,
                DEBUG("ibv_query_device_ex() failed");
                goto error;
        }
-       if (!switch_info->representor)
-               rte_strlcpy(name, dpdk_dev->name, sizeof(name));
-       else
-               snprintf(name, sizeof(name), "%s_representor_%u",
-                        dpdk_dev->name, switch_info->port_name);
        DRV_LOG(DEBUG, "naming Ethernet device \"%s\"", name);
        if (rte_eal_process_type() == RTE_PROC_SECONDARY) {
                eth_dev = rte_eth_dev_attach_secondary(name);
@@ -1421,9 +1429,9 @@ mlx5_pci_probe(struct rte_pci_driver *pci_drv __rte_unused,
                list[i].eth_dev = mlx5_dev_spawn
                        (&pci_dev->device, list[i].ibv_dev, vf, &list[i].info);
                if (!list[i].eth_dev) {
-                       if (rte_errno != EBUSY)
+                       if (rte_errno != EBUSY && rte_errno != EEXIST)
                                break;
-                       /* Device is disabled, ignore it. */
+                       /* Device is disabled or already spawned. Ignore it. */
                        continue;
                }
                restore = list[i].eth_dev->data->dev_flags;
@@ -1518,7 +1526,8 @@ static struct rte_pci_driver mlx5_driver = {
        },
        .id_table = mlx5_pci_id_map,
        .probe = mlx5_pci_probe,
-       .drv_flags = RTE_PCI_DRV_INTR_LSC | RTE_PCI_DRV_INTR_RMV,
+       .drv_flags = (RTE_PCI_DRV_INTR_LSC | RTE_PCI_DRV_INTR_RMV |
+                     RTE_PCI_DRV_PROBE_AGAIN),
 };
 
 #ifdef RTE_LIBRTE_MLX5_DLOPEN_DEPS