net/tap: fix to populate FDs in secondary process

When a tap device is hotplugged to primary process which in turn
adds the device to all secondary process, the secondary process
does a tap_mp_attach_queues, but the fds are not populated in
the primary during the probe they are populated during the queue_setup,
added a fix to sync the queues during rte_eth_dev_start

Fixes: 4852aa8f6e21 ("drivers/net: enable hotplug on secondary process")
Cc: stable@dpdk.org
Signed-off-by: Kumara Parameshwaran <kparameshwar@vmware.com>
Reviewed-by: Ferruh Yigit <ferruh.yigit@intel.com>

diff --git a/drivers/net/tap/rte_eth_tap.c b/drivers/net/tap/rte_eth_tap.c
index 02eb311e09f56e731c51b80442cb663776b5e054..111037de65ef3c89a212916fc72100b74f292bbd 100644 (file)
--- a/drivers/net/tap/rte_eth_tap.c
+++ b/drivers/net/tap/rte_eth_tap.c
@@ -67,6 +67,7 @@
 
 /* IPC key for queue fds sync */
 #define TAP_MP_KEY "tap_mp_sync_queues"
+#define TAP_MP_REQ_START_RXTX "tap_mp_req_start_rxtx"
 
 #define TAP_IOV_DEFAULT_MAX 1024
 
@@ -880,11 +881,49 @@ tap_link_set_up(struct rte_eth_dev *dev)
        return tap_ioctl(pmd, SIOCSIFFLAGS, &ifr, 1, LOCAL_AND_REMOTE);
 }
 
+static int
+tap_mp_req_on_rxtx(struct rte_eth_dev *dev)
+{
+       struct rte_mp_msg msg;
+       struct ipc_queues *request_param = (struct ipc_queues *)msg.param;
+       int err;
+       int fd_iterator = 0;
+       struct pmd_process_private *process_private = dev->process_private;
+       int i;
+
+       memset(&msg, 0, sizeof(msg));
+       strlcpy(msg.name, TAP_MP_REQ_START_RXTX, sizeof(msg.name));
+       strlcpy(request_param->port_name, dev->data->name, sizeof(request_param->port_name));
+       msg.len_param = sizeof(*request_param);
+       for (i = 0; i < dev->data->nb_tx_queues; i++) {
+               msg.fds[fd_iterator++] = process_private->txq_fds[i];
+               msg.num_fds++;
+               request_param->txq_count++;
+       }
+       for (i = 0; i < dev->data->nb_rx_queues; i++) {
+               msg.fds[fd_iterator++] = process_private->rxq_fds[i];
+               msg.num_fds++;
+               request_param->rxq_count++;
+       }
+
+       err = rte_mp_sendmsg(&msg);
+       if (err < 0) {
+               TAP_LOG(ERR, "Failed to send start req to secondary %d",
+                       rte_errno);
+               return -1;
+       }
+
+       return 0;
+}
+
 static int
 tap_dev_start(struct rte_eth_dev *dev)
 {
        int err, i;
 
+       if (rte_eal_process_type() == RTE_PROC_PRIMARY)
+               tap_mp_req_on_rxtx(dev);
+
        err = tap_intr_handle_set(dev, 1);
        if (err)
                return err;
@@ -901,6 +940,34 @@ tap_dev_start(struct rte_eth_dev *dev)
        return err;
 }
 
+static int
+tap_mp_req_start_rxtx(const struct rte_mp_msg *request, __rte_unused const void *peer)
+{
+       struct rte_eth_dev *dev;
+       const struct ipc_queues *request_param =
+               (const struct ipc_queues *)request->param;
+       int fd_iterator;
+       int queue;
+       struct pmd_process_private *process_private;
+
+       dev = rte_eth_dev_get_by_name(request_param->port_name);
+       if (!dev) {
+               TAP_LOG(ERR, "Failed to get dev for %s",
+                       request_param->port_name);
+               return -1;
+       }
+       process_private = dev->process_private;
+       fd_iterator = 0;
+       TAP_LOG(DEBUG, "tap_attach rx_q:%d tx_q:%d\n", request_param->rxq_count,
+               request_param->txq_count);
+       for (queue = 0; queue < request_param->txq_count; queue++)
+               process_private->txq_fds[queue] = request->fds[fd_iterator++];
+       for (queue = 0; queue < request_param->rxq_count; queue++)
+               process_private->rxq_fds[queue] = request->fds[fd_iterator++];
+
+       return 0;
+}
+
 /* This function gets called when the current port gets stopped.
  */
 static int
@@ -1092,6 +1159,9 @@ tap_dev_close(struct rte_eth_dev *dev)
 
        if (rte_eal_process_type() != RTE_PROC_PRIMARY) {
                rte_free(dev->process_private);
+               if (tap_devices_count == 1)
+                       rte_mp_action_unregister(TAP_MP_REQ_START_RXTX);
+               tap_devices_count--;
                return 0;
        }
 
@@ -2453,6 +2523,16 @@ rte_pmd_tap_probe(struct rte_vdev_device *dev)
                ret = tap_mp_attach_queues(name, eth_dev);
                if (ret != 0)
                        return -1;
+
+               if (!tap_devices_count) {
+                       ret = rte_mp_action_register(TAP_MP_REQ_START_RXTX, tap_mp_req_start_rxtx);
+                       if (ret < 0 && rte_errno != ENOTSUP) {
+                               TAP_LOG(ERR, "tap: Failed to register IPC callback: %s",
+                                       strerror(rte_errno));
+                               return -1;
+                       }
+               }
+               tap_devices_count++;
                rte_eth_dev_probing_finish(eth_dev);
                return 0;
        }