net/mlx5: remove redundant objects in probe function

This patch gets rid of redundant calls to open the device and query its
attributes in order to simplify the code.

Signed-off-by: Adrien Mazarguil <adrien.mazarguil@6wind.com>
Reviewed-by: Xueming Li <xuemingl@mellanox.com>

diff --git a/drivers/net/mlx5/mlx5.c b/drivers/net/mlx5/mlx5.c
index 99a7934..5523440 100644 (file)
--- a/drivers/net/mlx5/mlx5.c
+++ b/drivers/net/mlx5/mlx5.c
@@ -654,10 +654,10 @@ mlx5_pci_probe(struct rte_pci_driver *pci_drv __rte_unused,
 {
        struct ibv_device **list = NULL;
        struct ibv_device *ibv_dev;
+       struct ibv_context *ctx = NULL;
+       struct ibv_device_attr_ex attr;
        struct mlx5dv_context dv_attr = { .comp_mask = 0 };
        int err = 0;
-       struct ibv_context *attr_ctx = NULL;
-       struct ibv_device_attr_ex device_attr;
        unsigned int vf = 0;
        unsigned int mps;
        unsigned int cqe_comp;
@@ -714,12 +714,12 @@ mlx5_pci_probe(struct rte_pci_driver *pci_drv __rte_unused,
                       PCI_DEVICE_ID_MELLANOX_CONNECTX5VF) ||
                      (pci_dev->id.device_id ==
                       PCI_DEVICE_ID_MELLANOX_CONNECTX5EXVF));
-               attr_ctx = mlx5_glue->open_device(list[i]);
+               ctx = mlx5_glue->open_device(list[i]);
                rte_errno = errno;
                err = rte_errno;
                break;
        }
-       if (attr_ctx == NULL) {
+       if (ctx == NULL) {
                switch (err) {
                case 0:
                        DRV_LOG(ERR,
@@ -748,7 +748,7 @@ mlx5_pci_probe(struct rte_pci_driver *pci_drv __rte_unused,
 #ifdef HAVE_IBV_DEVICE_STRIDING_RQ_SUPPORT
        dv_attr.comp_mask |= MLX5DV_CONTEXT_MASK_STRIDING_RQ;
 #endif
-       mlx5_glue->dv_query_device(attr_ctx, &dv_attr);
+       mlx5_glue->dv_query_device(ctx, &dv_attr);
        if (dv_attr.flags & MLX5DV_CONTEXT_FLAGS_MPW_ALLOWED) {
                if (dv_attr.flags & MLX5DV_CONTEXT_FLAGS_ENHANCED_MPW) {
                        DRV_LOG(DEBUG, "enhanced MPW is supported");
@@ -822,23 +822,20 @@ mlx5_pci_probe(struct rte_pci_driver *pci_drv __rte_unused,
        DRV_LOG(WARNING, "MPLS over GRE/UDP tunnel offloading disabled due to"
                " old OFED/rdma-core version or firmware configuration");
 #endif
-       err = mlx5_glue->query_device_ex(attr_ctx, NULL, &device_attr);
+       err = mlx5_glue->query_device_ex(ctx, NULL, &attr);
        if (err) {
                DEBUG("ibv_query_device_ex() failed");
                goto error;
        }
-       DRV_LOG(INFO, "%u port(s) detected",
-               device_attr.orig_attr.phys_port_cnt);
-       for (i = 0; i < device_attr.orig_attr.phys_port_cnt; i++) {
+       DRV_LOG(INFO, "%u port(s) detected", attr.orig_attr.phys_port_cnt);
+       for (i = 0; i < attr.orig_attr.phys_port_cnt; i++) {
                char name[RTE_ETH_NAME_MAX_LEN];
                int len;
                uint32_t port = i + 1; /* ports are indexed from one */
-               struct ibv_context *ctx = NULL;
                struct ibv_port_attr port_attr;
                struct ibv_pd *pd = NULL;
                struct priv *priv = NULL;
                struct rte_eth_dev *eth_dev = NULL;
-               struct ibv_device_attr_ex device_attr_ex;
                struct ether_addr mac;
                struct mlx5_dev_config config = {
                        .cqe_comp = cqe_comp,
@@ -865,7 +862,7 @@ mlx5_pci_probe(struct rte_pci_driver *pci_drv __rte_unused,
                len = snprintf(name, sizeof(name), PCI_PRI_FMT,
                         pci_dev->addr.domain, pci_dev->addr.bus,
                         pci_dev->addr.devid, pci_dev->addr.function);
-               if (device_attr.orig_attr.phys_port_cnt > 1)
+               if (attr.orig_attr.phys_port_cnt > 1)
                        snprintf(name + len, sizeof(name), " port %u", i);
                if (rte_eal_process_type() == RTE_PROC_SECONDARY) {
                        eth_dev = rte_eth_dev_attach_secondary(name);
@@ -907,7 +904,8 @@ mlx5_pci_probe(struct rte_pci_driver *pci_drv __rte_unused,
                        continue;
                }
                DRV_LOG(DEBUG, "using port %u", port);
-               ctx = mlx5_glue->open_device(ibv_dev);
+               if (!ctx)
+                       ctx = mlx5_glue->open_device(ibv_dev);
                if (ctx == NULL) {
                        err = ENODEV;
                        goto port_error;
@@ -949,7 +947,7 @@ mlx5_pci_probe(struct rte_pci_driver *pci_drv __rte_unused,
                priv->ctx = ctx;
                strncpy(priv->ibdev_path, priv->ctx->device->ibdev_path,
                        sizeof(priv->ibdev_path));
-               priv->device_attr = device_attr;
+               priv->device_attr = attr;
                priv->port = port;
                priv->pd = pd;
                priv->mtu = ETHER_MTU;
@@ -960,17 +958,12 @@ mlx5_pci_probe(struct rte_pci_driver *pci_drv __rte_unused,
                                strerror(rte_errno));
                        goto port_error;
                }
-               err = mlx5_glue->query_device_ex(ctx, NULL, &device_attr_ex);
-               if (err) {
-                       DRV_LOG(ERR, "ibv_query_device_ex() failed");
-                       goto port_error;
-               }
-               config.hw_csum = !!(device_attr_ex.device_cap_flags_ex &
+               config.hw_csum = !!(attr.device_cap_flags_ex &
                                    IBV_DEVICE_RAW_IP_CSUM);
                DRV_LOG(DEBUG, "checksum offloading is %ssupported",
                        (config.hw_csum ? "" : "not "));
 #ifdef HAVE_IBV_DEVICE_COUNTERS_SET_SUPPORT
-               config.flow_counter_en = !!(device_attr.max_counter_sets);
+               config.flow_counter_en = !!attr.max_counter_sets;
                mlx5_glue->describe_counter_set(ctx, 0, &cs_desc);
                DRV_LOG(DEBUG,
                        "counter type = %d, num of cs = %ld, attributes = %d",
@@ -978,7 +971,7 @@ mlx5_pci_probe(struct rte_pci_driver *pci_drv __rte_unused,
                        cs_desc.attributes);
 #endif
                config.ind_table_max_size =
-                       device_attr_ex.rss_caps.max_rwq_indirection_table_size;
+                       attr.rss_caps.max_rwq_indirection_table_size;
                /* Remove this check once DPDK supports larger/variable
                 * indirection tables. */
                if (config.ind_table_max_size >
@@ -986,29 +979,28 @@ mlx5_pci_probe(struct rte_pci_driver *pci_drv __rte_unused,
                        config.ind_table_max_size = ETH_RSS_RETA_SIZE_512;
                DRV_LOG(DEBUG, "maximum Rx indirection table size is %u",
                        config.ind_table_max_size);
-               config.hw_vlan_strip = !!(device_attr_ex.raw_packet_caps &
+               config.hw_vlan_strip = !!(attr.raw_packet_caps &
                                         IBV_RAW_PACKET_CAP_CVLAN_STRIPPING);
                DRV_LOG(DEBUG, "VLAN stripping is %ssupported",
                        (config.hw_vlan_strip ? "" : "not "));
 
-               config.hw_fcs_strip = !!(device_attr_ex.raw_packet_caps &
+               config.hw_fcs_strip = !!(attr.raw_packet_caps &
                                         IBV_RAW_PACKET_CAP_SCATTER_FCS);
                DRV_LOG(DEBUG, "FCS stripping configuration is %ssupported",
                        (config.hw_fcs_strip ? "" : "not "));
 
 #ifdef HAVE_IBV_WQ_FLAG_RX_END_PADDING
-               config.hw_padding = !!device_attr_ex.rx_pad_end_addr_align;
+               config.hw_padding = !!attr.rx_pad_end_addr_align;
 #endif
                DRV_LOG(DEBUG,
                        "hardware Rx end alignment padding is %ssupported",
                        (config.hw_padding ? "" : "not "));
                config.vf = vf;
-               config.tso = ((device_attr_ex.tso_caps.max_tso > 0) &&
-                             (device_attr_ex.tso_caps.supported_qpts &
-                             (1 << IBV_QPT_RAW_PACKET)));
+               config.tso = (attr.tso_caps.max_tso > 0 &&
+                             (attr.tso_caps.supported_qpts &
+                              (1 << IBV_QPT_RAW_PACKET)));
                if (config.tso)
-                       config.tso_max_payload_sz =
-                                       device_attr_ex.tso_caps.max_tso;
+                       config.tso_max_payload_sz = attr.tso_caps.max_tso;
                if (config.mps && !mps) {
                        DRV_LOG(ERR,
                                "multi-packet send not supported on this device"
@@ -1170,14 +1162,18 @@ mlx5_pci_probe(struct rte_pci_driver *pci_drv __rte_unused,
                                 priv, mem_event_cb);
                rte_rwlock_write_unlock(&mlx5_shared_data->mem_event_rwlock);
                rte_eth_dev_probing_finish(eth_dev);
+               /*
+                * Each eth_dev instance is assigned its own Verbs context,
+                * since this one is consumed, let the next iteration open
+                * another.
+                */
+               ctx = NULL;
                continue;
 port_error:
                if (priv)
                        rte_free(priv);
                if (pd)
                        claim_zero(mlx5_glue->dealloc_pd(pd));
-               if (ctx)
-                       claim_zero(mlx5_glue->close_device(ctx));
                if (eth_dev && rte_eal_process_type() == RTE_PROC_PRIMARY)
                        rte_eth_dev_release_port(eth_dev);
                break;
@@ -1189,8 +1185,8 @@ port_error:
         * way to enumerate the registered ethdevs to free the previous ones.
         */
 error:
-       if (attr_ctx)
-               claim_zero(mlx5_glue->close_device(attr_ctx));
+       if (ctx)
+               claim_zero(mlx5_glue->close_device(ctx));
        if (list)
                mlx5_glue->free_device_list(list);
        if (err) {