netdev-dpdk: Arbitrary 'dpdk' port naming

'dpdk' ports no longer have naming restrictions. Now, instead of
specifying the dpdk port ID as part of the name, the PCI address of the
device must be specified via the 'dpdk-devargs' option. eg.

ovs-vsctl add-port br0 my-port
ovs-vsctl set Interface my-port type=dpdk
  options:dpdk-devargs=0000:06:00.3

The user must no longer hotplug attach DPDK ports by issuing the
specific ovs-appctl netdev-dpdk/attach command. The hotplug is now
automatically invoked when a valid PCI address is set in the
dpdk-devargs. The format for ovs-appctl netdev-dpdk/detach command
has changed in that the user now must specify the relevant PCI address
as input instead of the port name.

Signed-off-by: Ciara Loftus <ciara.loftus@intel.com>
Signed-off-by: Kevin Traynor <ktraynor@redhat.com>
Co-authored-by: Kevin Traynor <ktraynor@redhat.com>
Acked-by: Stephen Finucane <stephen@that.guru>  # docs only
Signed-off-by: Daniele Di Proietto <diproiettod@vmware.com>

Documentation/howto/dpdk.rst

@@ -312,14 +312,13 @@ In order to attach a port, it has to be bound to DPDK using the
 
 Then it can be attached to OVS::
 
-    $ ovs-appctl netdev-dpdk/attach 0000:01:00.0
-
-At this point, the user can create a dpdk port using the ``add-port`` command.
+    $ ovs-vsctl add-port br0 dpdkx -- set Interface dpdkx type=dpdk \
+        options:dpdk-devargs=0000:01:00.0
 
 It is also possible to detach a port from ovs, the user has to remove the
 port using the del-port command, then it can be detached using::
 
-    $ ovs-appctl netdev-dpdk/detach dpdk0
+    $ ovs-appctl netdev-dpdk/detach dpdkx
 
 This feature is not supported with VFIO and does not work with some NICs.
 For more information please refer to the `DPDK Port Hotplug Framework

Documentation/intro/install/dpdk.rst

@@ -252,8 +252,13 @@ ports. For example, to create a userspace bridge named ``br0`` and add two
 ``dpdk`` ports to it, run::
 
     $ ovs-vsctl add-br br0 -- set bridge br0 datapath_type=netdev
-    $ ovs-vsctl add-port br0 dpdk0 -- set Interface dpdk0 type=dpdk
-    $ ovs-vsctl add-port br0 dpdk1 -- set Interface dpdk1 type=dpdk
+    $ ovs-vsctl add-port br0 myportnameone -- set Interface myportnameone \
+        type=dpdk options:dpdk-devargs=0000:06:00.0
+    $ ovs-vsctl add-port br0 myportnametwo -- set Interface myportnametwo \
+        type=dpdk options:dpdk-devargs=0000:06:00.1
+
+DPDK devices will not be available for use until a valid dpdk-devargs is
+specified.
 
 Refer to ovs-vsctl(8) and :doc:`/howto/dpdk` for more details.
 

NEWS

@@ -56,6 +56,11 @@ Post-v2.6.0
      * Support for DPDK v16.11.
      * Support for rx checksum offload. Refer DPDK HOWTO for details.
      * Port Hotplug is now supported.
+     * DPDK physical ports can now have arbitrary names. The PCI address of
+       the device must be set using the 'dpdk-devargs' option. Compatibility
+       with the old dpdk<portid> naming scheme is broken, and as such a
+       device will not be available for use until a valid dpdk-devargs is
+       specified.
    - Fedora packaging:
      * A package upgrade does not automatically restart OVS service.
    - ovs-vswitchd/ovs-vsctl:

lib/netdev-dpdk.c

@@ -356,6 +356,9 @@ struct netdev_dpdk {
     /* Identifier used to distinguish vhost devices from each other. */
     char vhost_id[PATH_MAX];
 
+    /* Device arguments for dpdk ports */
+    char *devargs;
+
     /* In dpdk_list. */
     struct ovs_list list_node OVS_GUARDED_BY(dpdk_mutex);
 
@@ -846,7 +849,7 @@ netdev_dpdk_init(struct netdev *netdev, unsigned int port_no,
     /* If the 'sid' is negative, it means that the kernel fails
      * to obtain the pci numa info.  In that situation, always
      * use 'SOCKET0'. */
-    if (type == DPDK_DEV_ETH) {
+    if (type == DPDK_DEV_ETH && rte_eth_dev_is_valid_port(dev->port_id)) {
         sid = rte_eth_dev_socket_id(port_no);
     } else {
         sid = rte_lcore_to_socket_id(rte_get_master_lcore());
@@ -888,9 +891,11 @@ netdev_dpdk_init(struct netdev *netdev, unsigned int port_no,
     /* Initilize the hardware offload flags to 0 */
     dev->hw_ol_features = 0;
     if (type == DPDK_DEV_ETH) {
-        err = dpdk_eth_dev_init(dev);
-        if (err) {
-            goto unlock;
+        if (rte_eth_dev_is_valid_port(dev->port_id)) {
+            err = dpdk_eth_dev_init(dev);
+            if (err) {
+                goto unlock;
+            }
         }
         dev->tx_q = netdev_dpdk_alloc_txq(netdev->n_txq);
     } else {
@@ -986,17 +991,10 @@ netdev_dpdk_vhost_client_construct(struct netdev *netdev)
 static int
 netdev_dpdk_construct(struct netdev *netdev)
 {
-    unsigned int port_no;
     int err;
 
-    /* Names always start with "dpdk" */
-    err = dpdk_dev_parse_name(netdev->name, "dpdk", &port_no);
-    if (err) {
-        return err;
-    }
-
     ovs_mutex_lock(&dpdk_mutex);
-    err = netdev_dpdk_init(netdev, port_no, DPDK_DEV_ETH);
+    err = netdev_dpdk_init(netdev, -1, DPDK_DEV_ETH);
     ovs_mutex_unlock(&dpdk_mutex);
     return err;
 }
@@ -1010,6 +1008,7 @@ netdev_dpdk_destruct(struct netdev *netdev)
     ovs_mutex_lock(&dev->mutex);
 
     rte_eth_dev_stop(dev->port_id);
+    free(dev->devargs);
     free(ovsrcu_get_protected(struct ingress_policer *,
                               &dev->ingress_policer));
 
@@ -1117,6 +1116,49 @@ netdev_dpdk_get_config(const struct netdev *netdev, struct smap *args)
     return 0;
 }
 
+static struct netdev_dpdk *
+netdev_dpdk_lookup_by_port_id(int port_id)
+    OVS_REQUIRES(dpdk_mutex)
+{
+    struct netdev_dpdk *dev;
+
+    LIST_FOR_EACH (dev, list_node, &dpdk_list) {
+        if (dev->port_id == port_id) {
+            return dev;
+        }
+    }
+
+    return NULL;
+}
+
+static int
+netdev_dpdk_process_devargs(const char *devargs)
+{
+    struct rte_pci_addr addr;
+    uint8_t new_port_id = UINT8_MAX;
+
+    if (!eal_parse_pci_DomBDF(devargs, &addr)) {
+        /* Valid PCI address format detected - configure physical device */
+        if (!rte_eth_dev_count()
+                || rte_eth_dev_get_port_by_name(devargs, &new_port_id)
+                || !rte_eth_dev_is_valid_port(new_port_id)) {
+            /* PCI device not found in DPDK, attempt to attach it */
+            if (!rte_eth_dev_attach(devargs, &new_port_id)) {
+                /* Attach successful */
+                VLOG_INFO("Device "PCI_PRI_FMT" has been attached to DPDK",
+                          addr.domain, addr.bus, addr.devid, addr.function);
+            } else {
+                /* Attach unsuccessful */
+                VLOG_INFO("Error attaching device "PCI_PRI_FMT" to DPDK",
+                          addr.domain, addr.bus, addr.devid, addr.function);
+                return -1;
+            }
+        }
+    }
+
+    return new_port_id;
+}
+
 static void
 dpdk_set_rxq_config(struct netdev_dpdk *dev, const struct smap *args)
     OVS_REQUIRES(dev->mutex)
@@ -1159,7 +1201,10 @@ netdev_dpdk_set_config(struct netdev *netdev, const struct smap *args)
     };
     bool rx_chksm_ofld;
     bool temp_flag;
+    const char *new_devargs;
+    int err = 0;
 
+    ovs_mutex_lock(&dpdk_mutex);
     ovs_mutex_lock(&dev->mutex);
 
     dpdk_set_rxq_config(dev, args);
@@ -1171,6 +1216,53 @@ netdev_dpdk_set_config(struct netdev *netdev, const struct smap *args)
                             NIC_PORT_DEFAULT_TXQ_SIZE,
                             &dev->requested_txq_size);
 
+    new_devargs = smap_get(args, "dpdk-devargs");
+
+    if (dev->devargs && strcmp(new_devargs, dev->devargs)) {
+        /* The user requested a new device.  If we return error, the caller
+         * will delete this netdev and try to recreate it. */
+        err = EAGAIN;
+        goto out;
+    }
+
+    /* dpdk-devargs is required for device configuration */
+    if (new_devargs && new_devargs[0]) {
+        /* Don't process dpdk-devargs if value is unchanged and port id
+         * is valid */
+        if (!(dev->devargs && !strcmp(dev->devargs, new_devargs)
+               && rte_eth_dev_is_valid_port(dev->port_id))) {
+            int new_port_id = netdev_dpdk_process_devargs(new_devargs);
+            if (!rte_eth_dev_is_valid_port(new_port_id)) {
+                err = EINVAL;
+            } else if (new_port_id == dev->port_id) {
+                /* Already configured, do not reconfigure again */
+                err = 0;
+            } else {
+                struct netdev_dpdk *dup_dev;
+                dup_dev = netdev_dpdk_lookup_by_port_id(new_port_id);
+                if (dup_dev) {
+                    VLOG_WARN("'%s' is trying to use device '%s' which is "
+                              "already in use by '%s'.",
+                              netdev_get_name(netdev), new_devargs,
+                              netdev_get_name(&dup_dev->up));
+                    err = EADDRINUSE;
+                } else {
+                    dev->devargs = xstrdup(new_devargs);
+                    dev->port_id = new_port_id;
+                    netdev_request_reconfigure(&dev->up);
+                    err = 0;
+                }
+            }
+        }
+    } else {
+        /* dpdk-devargs unspecified - can't configure device */
+        err = EINVAL;
+    }
+
+    if (err) {
+        goto out;
+    }
+
     rx_fc_en = smap_get_bool(args, "rx-flow-ctrl", false);
     tx_fc_en = smap_get_bool(args, "tx-flow-ctrl", false);
     autoneg = smap_get_bool(args, "flow-ctrl-autoneg", false);
@@ -1191,9 +1283,12 @@ netdev_dpdk_set_config(struct netdev *netdev, const struct smap *args)
         dev->hw_ol_features ^= NETDEV_RX_CHECKSUM_OFFLOAD;
         dpdk_eth_checksum_offload_configure(dev);
     }
-    ovs_mutex_unlock(&dev->mutex);
 
-    return 0;
+out:
+    ovs_mutex_unlock(&dev->mutex);
+    ovs_mutex_unlock(&dpdk_mutex);
+
+    return err;
 }
 
 static int
@@ -2357,58 +2452,36 @@ netdev_dpdk_set_admin_state(struct unixctl_conn *conn, int argc,
     unixctl_command_reply(conn, "OK");
 }
 
-static void
-netdev_dpdk_attach(struct unixctl_conn *conn, int argc OVS_UNUSED,
-                   const char *argv[], void *aux OVS_UNUSED)
-{
-    int ret;
-    char *response;
-    uint8_t port_id;
-
-    ovs_mutex_lock(&dpdk_mutex);
-
-    ret = rte_eth_dev_attach(argv[1], &port_id);
-    if (ret < 0) {
-        response = xasprintf("Error attaching device '%s'", argv[1]);
-        ovs_mutex_unlock(&dpdk_mutex);
-        unixctl_command_reply_error(conn, response);
-        free(response);
-        return;
-    }
-
-    response = xasprintf("Device '%s' has been attached as 'dpdk%d'",
-                         argv[1], port_id);
-
-    ovs_mutex_unlock(&dpdk_mutex);
-    unixctl_command_reply(conn, response);
-    free(response);
-}
-
 static void
 netdev_dpdk_detach(struct unixctl_conn *conn, int argc OVS_UNUSED,
                    const char *argv[], void *aux OVS_UNUSED)
 {
     int ret;
     char *response;
-    unsigned int parsed_port;
     uint8_t port_id;
     char devname[RTE_ETH_NAME_MAX_LEN];
+    struct rte_pci_addr addr;
+    struct netdev_dpdk *dev;
 
     ovs_mutex_lock(&dpdk_mutex);
 
-    ret = dpdk_dev_parse_name(argv[1], "dpdk", &parsed_port);
-    if (ret) {
-        response = xasprintf("'%s' is not a valid port", argv[1]);
+    if (eal_parse_pci_DomBDF(argv[1], &addr)) {
+        response = xasprintf("Invalid PCI address '%s'. Cannot detach.",
+                             argv[1]);
         goto error;
     }
 
-    port_id = parsed_port;
+    if (!rte_eth_dev_count() || rte_eth_dev_get_port_by_name(argv[1],
+                                                             &port_id)) {
+        response = xasprintf("Device '%s' not found in DPDK", argv[1]);
+        goto error;
+    }
 
-    struct netdev *netdev = netdev_from_name(argv[1]);
-    if (netdev) {
-        netdev_close(netdev);
-        response = xasprintf("Port '%s' is being used. Remove it before"
-                             "detaching", argv[1]);
+    dev = netdev_dpdk_lookup_by_port_id(port_id);
+    if (dev) {
+        response = xasprintf("Device '%s' is being used by interface '%s'. "
+                             "Remove it before detaching",
+                             argv[1], netdev_get_name(&dev->up));
         goto error;
     }
 
@@ -2416,11 +2489,11 @@ netdev_dpdk_detach(struct unixctl_conn *conn, int argc OVS_UNUSED,
 
     ret = rte_eth_dev_detach(port_id, devname);
     if (ret < 0) {
-        response = xasprintf("Port '%s' can not be detached", argv[1]);
+        response = xasprintf("Device '%s' can not be detached", argv[1]);
         goto error;
     }
 
-    response = xasprintf("Port '%s' has been detached", argv[1]);
+    response = xasprintf("Device '%s' has been detached", argv[1]);
 
     ovs_mutex_unlock(&dpdk_mutex);
     unixctl_command_reply(conn, response);
@@ -2708,11 +2781,8 @@ netdev_dpdk_class_init(void)
         unixctl_command_register("netdev-dpdk/set-admin-state",
                                  "[netdev] up|down", 1, 2,
                                  netdev_dpdk_set_admin_state, NULL);
-        unixctl_command_register("netdev-dpdk/attach",
-                                 "pci address of device", 1, 1,
-                                 netdev_dpdk_attach, NULL);
         unixctl_command_register("netdev-dpdk/detach",
-                                 "port", 1, 1,
+                                 "pci address of device", 1, 1,
                                  netdev_dpdk_detach, NULL);
 
         ovsthread_once_done(&once);

vswitchd/vswitch.xml

@@ -2303,6 +2303,14 @@
         </p>
       </column>
 
+      <column name="options" key="dpdk-devargs"
+              type='{"type": "string"}'>
+        <p>
+          Specifies the PCI address of a physical dpdk device.
+          Only supported by 'dpdk' devices.
+        </p>
+      </column>
+
       <column name="other_config" key="pmd-rxq-affinity">
         <p>Specifies mapping of RX queues of this interface to CPU cores.</p>
         <p>Value should be set in the following form:</p>