btl tcp: Simplify module address storage

Today, a btl tcp module is associated with exactly one IP
address (IPv4 or IPv6).  There's no need to reserve space
for both an IPv4 and IPv6 address in the module structure,
since the module will only be associated with one or the
other.

Signed-off-by: Brian Barrett <bbarrett@amazon.com>

Author: bwbarrett

opal/mca/btl/tcp/btl_tcp.h

@@ -164,13 +164,11 @@ OPAL_MODULE_DECLSPEC extern mca_btl_tcp_component_t mca_btl_tcp_component;
 struct mca_btl_tcp_module_t {
     mca_btl_base_module_t  super;  /**< base BTL interface */
     uint16_t           tcp_ifkindex; /** <BTL kernel interface index */
-#if 0
-    int                tcp_ifindex; /**< BTL interface index */
-#endif
-    struct sockaddr_storage tcp_ifaddr; /**< First IPv4 address discovered for this interface, bound as sending address for this BTL */
-#if OPAL_ENABLE_IPV6
-    struct sockaddr_storage tcp_ifaddr_6; /**< First IPv6 address discovered for this interface, bound as sending address for this BTL  */
-#endif
+    struct sockaddr_storage tcp_ifaddr;   /**< First address
+                                             discovered for this
+                                             interface, bound as
+                                             sending address for this
+                                             BTL */
     uint32_t           tcp_ifmask;  /**< BTL interface netmask */
 
     opal_mutex_t       tcp_endpoints_mutex;

opal/mca/btl/tcp/btl_tcp_component.c

@@ -513,17 +513,12 @@ static int mca_btl_tcp_create(int if_kindex, const char* if_name)
         btl->tcp_send_handler = 0;
 #endif
 
-       struct sockaddr_storage addr;
-       opal_ifkindextoaddr(if_kindex, (struct sockaddr*) &addr,
-                                          sizeof (struct sockaddr_storage));
-#if OPAL_ENABLE_IPV6
-        if (addr.ss_family == AF_INET6) {
-            btl->tcp_ifaddr_6 =  addr;
-        }
-#endif
-        if (addr.ss_family == AF_INET) {
-           btl->tcp_ifaddr = addr;
-        }
+        /* save the address associated with this kindex in the module
+           to publish in the modex and use as the source of all packets
+           from this module */
+        opal_ifkindextoaddr(if_kindex, (struct sockaddr*)&btl->tcp_ifaddr,
+                            sizeof (struct sockaddr_storage));
+
         /* allow user to specify interface bandwidth */
         sprintf(param, "bandwidth_%s", if_name);
         mca_btl_tcp_param_register_uint(param, NULL, btl->super.btl_bandwidth, OPAL_INFO_LVL_5, &btl->super.btl_bandwidth);
@@ -567,8 +562,8 @@ static int mca_btl_tcp_create(int if_kindex, const char* if_name)
         opal_output_verbose(5, opal_btl_base_framework.framework_output,
                             "btl:tcp: %p: if %s kidx %d cnt %i addr %s %s bw %d lt %d\n",
                             (void*)btl, if_name, (int) btl->tcp_ifkindex, i,
-                            opal_net_get_hostname((struct sockaddr*)&addr),
-                            (addr.ss_family == AF_INET) ? "IPv4" : "IPv6",
+                            opal_net_get_hostname((struct sockaddr*)&btl->tcp_ifaddr),
+                            (btl->tcp_ifaddr.ss_family == AF_INET) ? "IPv4" : "IPv6",
                             btl->super.btl_bandwidth, btl->super.btl_latency);
     }
     return OPAL_SUCCESS;
@@ -721,6 +716,7 @@ static int mca_btl_tcp_component_create_instances(void)
          */
         for(if_index = opal_ifbegin(); if_index >= 0; if_index = opal_ifnext(if_index)){
             int index = opal_ifindextokindex (if_index);
+
             if (index > 0) {
                 bool want_this_if = true;
 
@@ -1172,7 +1168,7 @@ static int mca_btl_tcp_component_exchange(void)
                      (6 != mca_btl_tcp_component.tcp_disable_family)) {
                      memcpy(&addrs[current_addr].addr_inet,
                              &((struct sockaddr_in6*)&my_ss)->sin6_addr,
-                             sizeof(addrs[0].addr_inet));
+                            sizeof(addrs[0].addr_inet));
                      addrs[current_addr].addr_port =
                          mca_btl_tcp_component.tcp6_listen_port;
                      addrs[current_addr].addr_family = MCA_BTL_TCP_AF_INET6;

opal/mca/btl/tcp/btl_tcp_endpoint.c

@@ -743,11 +743,11 @@ static int mca_btl_tcp_endpoint_start_connect(mca_btl_base_endpoint_t* btl_endpo
 #if OPAL_ENABLE_IPV6
     if (endpoint_addr.ss_family == AF_INET6) {
         assert(NULL != &btl_endpoint->endpoint_btl->tcp_ifaddr_6);
-        if (bind(btl_endpoint->endpoint_sd, (struct sockaddr*) &btl_endpoint->endpoint_btl->tcp_ifaddr_6,
+        if (bind(btl_endpoint->endpoint_sd, (struct sockaddr*) &btl_endpoint->endpoint_btl->tcp_ifaddr,
                  sizeof(struct sockaddr_in6)) < 0) {
             BTL_ERROR(("bind on local address (%s:%d) failed: %s (%d)",
                        opal_net_get_hostname((struct sockaddr*) &btl_endpoint->endpoint_btl->tcp_ifaddr),
-                       htons(((struct sockaddr_in*)&btl_endpoint->endpoint_btl->tcp_ifaddr)->sin_port),
+                       htons(((struct sockaddr_in6*)&btl_endpoint->endpoint_btl->tcp_ifaddr)->sin6_port),
                        strerror(opal_socket_errno), opal_socket_errno));
 
             CLOSE_THE_SOCKET(btl_endpoint->endpoint_sd);