net/memif: enable loopback

With this patch it is possible to connect 2 DPDK memifs into loopback,
i.e. when they have the same id and different roles, as for example:
  "--vdev=net_memif0,role=master,id=0"
  "--vdev=net_memif1,role=slave,id=0"

Signed-off-by: Július Milan <jmilan.dev@gmail.com>
Reviewed-by: Jakub Grajciar <jgrajcia@cisco.com>

diff --git a/doc/guides/nics/memif.rst b/doc/guides/nics/memif.rst
index 4d7f008..08a9fda 100644 (file)
--- a/doc/guides/nics/memif.rst
+++ b/doc/guides/nics/memif.rst
@@ -272,3 +272,21 @@ Send ping from VPP::
     64 bytes from 192.168.1.2: icmp_seq=3 ttl=254 time=23.3927 ms
     64 bytes from 192.168.1.2: icmp_seq=4 ttl=254 time=24.2975 ms
     64 bytes from 192.168.1.2: icmp_seq=5 ttl=254 time=17.7049 ms
+
+Example: testpmd memif loopback
+-------------------------------
+In this example we will create 2 memif ports connected into loopback.
+The situation is analogous to cross connecting 2 ports of the NIC by cable.
+
+To set the loopback, just use the same socket and id with different roles::
+
+    #./testpmd --vdev=net_memif0,role=master,id=0 --vdev=net_memif1,role=slave,id=0 -- -i
+
+Then start the communication::
+
+    testpmd> start tx_first
+
+Finally we can check port stats to see the traffic::
+
+    testpmd> show port stats all
+    testpmd> show port stats all

diff --git a/drivers/net/memif/memif_socket.c b/drivers/net/memif/memif_socket.c
index ad5e30b..8ce2cc9 100644 (file)
--- a/drivers/net/memif/memif_socket.c
+++ b/drivers/net/memif/memif_socket.c
@@ -203,7 +203,7 @@ memif_msg_receive_init(struct memif_control_channel *cc, memif_msg_t *msg)
                dev = elt->dev;
                pmd = dev->data->dev_private;
                if (((pmd->flags & ETH_MEMIF_FLAG_DISABLED) == 0) &&
-                   pmd->id == i->id) {
+                   (pmd->id == i->id) && (pmd->role == MEMIF_ROLE_MASTER)) {
                        /* assign control channel to device */
                        cc->dev = dev;
                        pmd->cc = cc;
@@ -528,6 +528,7 @@ memif_disconnect(struct rte_eth_dev *dev)
        pmd->flags &= ~ETH_MEMIF_FLAG_CONNECTING;
        pmd->flags &= ~ETH_MEMIF_FLAG_CONNECTED;
 
+       rte_spinlock_lock(&pmd->cc_lock);
        if (pmd->cc != NULL) {
                /* Clear control message queue (except disconnect message if any). */
                for (elt = TAILQ_FIRST(&pmd->cc->msg_queue); elt != NULL; elt = next) {
@@ -570,6 +571,7 @@ memif_disconnect(struct rte_eth_dev *dev)
                                        "Failed to unregister control channel callback.");
                }
        }
+       rte_spinlock_unlock(&pmd->cc_lock);
 
        /* unconfig interrupts */
        for (i = 0; i < pmd->cfg.num_s2m_rings; i++) {
@@ -612,7 +614,8 @@ memif_disconnect(struct rte_eth_dev *dev)
        /* reset connection configuration */
        memset(&pmd->run, 0, sizeof(pmd->run));
 
-       MIF_LOG(DEBUG, "Disconnected.");
+       MIF_LOG(DEBUG, "Disconnected, id: %d, role: %s.", pmd->id,
+               (pmd->role == MEMIF_ROLE_MASTER) ? "master" : "slave");
 }
 
 static int
@@ -642,8 +645,12 @@ memif_msg_receive(struct memif_control_channel *cc)
 
        size = recvmsg(cc->intr_handle.fd, &mh, 0);
        if (size != sizeof(memif_msg_t)) {
-               MIF_LOG(DEBUG, "Invalid message size.");
-               memif_msg_enq_disconnect(cc, "Invalid message size", 0);
+               MIF_LOG(DEBUG, "Invalid message size = %zd", size);
+               if (size > 0)
+                       /* 0 means end-of-file, negative size means error,
+                        * don't send further disconnect message in such cases.
+                        */
+                       memif_msg_enq_disconnect(cc, "Invalid message size", 0);
                return -1;
        }
        MIF_LOG(DEBUG, "Received msg type: %u.", msg.type);
@@ -965,20 +972,11 @@ memif_socket_init(struct rte_eth_dev *dev, const char *socket_filename)
        }
        pmd->socket_filename = socket->filename;
 
-       if (socket->listener != 0 && pmd->role == MEMIF_ROLE_SLAVE) {
-               MIF_LOG(ERR, "Socket is a listener.");
-               return -1;
-       } else if ((socket->listener == 0) && (pmd->role == MEMIF_ROLE_MASTER)) {
-               MIF_LOG(ERR, "Socket is not a listener.");
-               return -1;
-       }
-
        TAILQ_FOREACH(elt, &socket->dev_queue, next) {
                tmp_pmd = elt->dev->data->dev_private;
-               if (tmp_pmd->id == pmd->id) {
-                       MIF_LOG(ERR, "Memif device with id %d already "
-                               "exists on socket %s",
-                               pmd->id, socket->filename);
+               if (tmp_pmd->id == pmd->id && tmp_pmd->role == pmd->role) {
+                       MIF_LOG(ERR, "Two interfaces with the same id (%d) can "
+                               "not have the same role.", pmd->id);
                        return -1;
                }
        }

diff --git a/drivers/net/memif/rte_eth_memif.c b/drivers/net/memif/rte_eth_memif.c
index 27c0f09..81d71c5 100644 (file)
--- a/drivers/net/memif/rte_eth_memif.c
+++ b/drivers/net/memif/rte_eth_memif.c
@@ -1491,6 +1491,7 @@ memif_create(struct rte_vdev_device *vdev, enum memif_role_t role,
        pmd->cfg.num_m2s_rings = 0;
 
        pmd->cfg.pkt_buffer_size = pkt_buffer_size;
+       rte_spinlock_init(&pmd->cc_lock);
 
        data = eth_dev->data;
        data->dev_private = pmd;

diff --git a/drivers/net/memif/rte_eth_memif.h b/drivers/net/memif/rte_eth_memif.h
index 0d25663..6f45b70 100644 (file)
--- a/drivers/net/memif/rte_eth_memif.h
+++ b/drivers/net/memif/rte_eth_memif.h
@@ -94,6 +94,7 @@ struct pmd_internals {
        char secret[ETH_MEMIF_SECRET_SIZE]; /**< secret (optional security parameter) */
 
        struct memif_control_channel *cc;       /**< control channel */
+       rte_spinlock_t cc_lock;                 /**< control channel lock */
 
        /* remote info */
        char remote_name[RTE_DEV_NAME_MAX_LEN];         /**< remote app name */