[RPC] Add the IPV6 support for server side auto tuning (#2462)

* use IPV6 instead of IPV4

* backward compatible

* add error report

* fix linter

* more linter

* fix the python2 api

python/tvm/exec/rpc_server.py

@@ -12,7 +12,7 @@ def main(args):
     """Main function"""
 
     if args.tracker:
-        url, port = args.tracker.split(":")
+        url, port = args.tracker.rsplit(":", 1)
         port = int(port)
         tracker_addr = (url, port)
         if not args.key:

python/tvm/rpc/base.py

@@ -42,6 +42,11 @@ class TrackerCode(object):
 RPC_SESS_MASK = 128
 
 
+def get_addr_family(addr):
+    res = socket.getaddrinfo(addr[0], addr[1], 0, 0, socket.IPPROTO_TCP)
+    return res[0][0]
+
+
 def recvall(sock, nbytes):
     """Receive all nbytes from socket.
 
@@ -142,7 +147,7 @@ def connect_with_retry(addr, timeout=60, retry_period=5):
     tstart = time.time()
     while True:
         try:
-            sock = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
+            sock = socket.socket(get_addr_family(addr), socket.SOCK_STREAM)
             sock.connect(addr)
             return sock
         except socket.error as sock_err:

python/tvm/rpc/proxy.py

@@ -298,7 +298,8 @@ class ProxyServerHandler(object):
         """Update information on tracker."""
         try:
             if self._tracker_conn is None:
-                self._tracker_conn = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
+                self._tracker_conn = socket.socket(base.get_addr_family(self._tracker_addr),
+                                                   socket.SOCK_STREAM)
                 self._tracker_conn.connect(self._tracker_addr)
                 self._tracker_conn.sendall(struct.pack("<i", base.RPC_TRACKER_MAGIC))
                 magic = struct.unpack("<i", base.recvall(self._tracker_conn, 4))[0]
@@ -481,7 +482,7 @@ class Proxy(object):
                  tracker_addr=None,
                  index_page=None,
                  resource_files=None):
-        sock = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
+        sock = socket.socket(base.get_addr_family((host, port)), socket.SOCK_STREAM)
         self.port = None
         for my_port in range(port, port_end):
             try:

python/tvm/rpc/server.py

@@ -201,7 +201,7 @@ def _connect_proxy_loop(addr, key, load_library):
     retry_period = 5
     while True:
         try:
-            sock = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
+            sock = socket.socket(base.get_addr_family(addr), socket.SOCK_STREAM)
             sock.connect(addr)
             sock.sendall(struct.pack("<i", base.RPC_MAGIC))
             sock.sendall(struct.pack("<i", len(key)))
@@ -334,7 +334,7 @@ class Server(object):
             self.proc = subprocess.Popen(cmd, preexec_fn=os.setsid)
             time.sleep(0.5)
         elif not is_proxy:
-            sock = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
+            sock = socket.socket(base.get_addr_family((host, port)), socket.SOCK_STREAM)
             self.port = None
             for my_port in range(port, port_end):
                 try:

python/tvm/rpc/tracker.py

@@ -366,7 +366,7 @@ class Tracker(object):
         if silent:
             logger.setLevel(logging.WARN)
 
-        sock = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
+        sock = socket.socket(base.get_addr_family((host, port)), socket.SOCK_STREAM)
         self.port = None
         self.stop_key = base.random_key("tracker")
         for my_port in range(port, port_end):
@@ -391,7 +391,7 @@ class Tracker(object):
         sock.close()
 
     def _stop_tracker(self):
-        sock = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
+        sock = socket.socket(base.get_addr_family((self.host, self.port)), socket.SOCK_STREAM)
         sock.connect((self.host, self.port))
         sock.sendall(struct.pack("<i", base.RPC_TRACKER_MAGIC))
         magic = struct.unpack("<i", base.recvall(sock, 4))[0]

src/common/socket.h

@@ -45,7 +45,7 @@ inline std::string GetHostName() {
  * \brief Common data structure fornetwork address.
  */
 struct SockAddr {
-  sockaddr_in addr;
+  sockaddr_storage addr;
   SockAddr() {}
   /*!
    * \brief construc address by url and port
@@ -63,30 +63,63 @@ struct SockAddr {
   void Set(const char *host, int port) {
     addrinfo hints;
     memset(&hints, 0, sizeof(hints));
-    hints.ai_family = AF_INET;
+    hints.ai_family = PF_UNSPEC;
+    hints.ai_flags = AI_PASSIVE;
     hints.ai_protocol = SOCK_STREAM;
     addrinfo *res = NULL;
     int sig = getaddrinfo(host, NULL, &hints, &res);
     CHECK(sig == 0 && res != NULL)
         << "cannot obtain address of " <<  host;
-    CHECK(res->ai_family == AF_INET)
-        << "Does not support IPv6";
-    memcpy(&addr, res->ai_addr, res->ai_addrlen);
-    addr.sin_port = htons(port);
+    switch (res->ai_family) {
+      case AF_INET: {
+          sockaddr_in *addr4 = reinterpret_cast<sockaddr_in *>(&addr);
+          memcpy(addr4, res->ai_addr, res->ai_addrlen);
+          addr4->sin_port = htons(port);
+          addr4->sin_family = AF_INET;
+        }
+        break;
+      case AF_INET6: {
+          sockaddr_in6 *addr6 = reinterpret_cast<sockaddr_in6 *>(&addr);
+          memcpy(addr6, res->ai_addr, res->ai_addrlen);
+          addr6->sin6_port = htons(port);
+          addr6->sin6_family = AF_INET6;
+        }
+        break;
+      default:
+        CHECK(false) << "cannot decode address";
+    }
     freeaddrinfo(res);
   }
   /*! \brief return port of the address */
   int port() const {
-    return ntohs(addr.sin_port);
+    return ntohs((addr.ss_family == AF_INET6)? \
+                    reinterpret_cast<const sockaddr_in6 *>(&addr)->sin6_port : \
+                    reinterpret_cast<const sockaddr_in *>(&addr)->sin_port);
+  }
+  /*! \brief return the ip address family */
+  int ss_family() const {
+    return addr.ss_family;
   }
   /*! \return a string representation of the address */
   std::string AsString() const {
     std::string buf; buf.resize(256);
+
+  const void *sinx_addr = nullptr;
+  if (addr.ss_family == AF_INET6) {
+    const in6_addr& addr6 = reinterpret_cast<const sockaddr_in6 *>(&addr)->sin6_addr;
+    sinx_addr = reinterpret_cast<const void *>(&addr6);
+  } else if (addr.ss_family == AF_INET) {
+    const in_addr& addr4 = reinterpret_cast<const sockaddr_in *>(&addr)->sin_addr;
+    sinx_addr = reinterpret_cast<const void *>(&addr4);
+  } else {
+    CHECK(false) << "illegal address";
+  }
+
 #ifdef _WIN32
-    const char *s = inet_ntop(AF_INET, (PVOID)&addr.sin_addr,
+    const char *s = inet_ntop(addr.ss_family, sinx_addr,
                               &buf[0], buf.length());
 #else
-    const char *s = inet_ntop(AF_INET, &addr.sin_addr,
+    const char *s = inet_ntop(addr.ss_family, sinx_addr,
                               &buf[0], static_cast<socklen_t>(buf.length()));
 #endif
     CHECK(s != nullptr) << "cannot decode address";
@@ -294,7 +327,7 @@ class TCPSocket : public Socket {
    * \param af domain
    */
   void Create(int af = PF_INET) {
-    sockfd = socket(PF_INET, SOCK_STREAM, 0);
+    sockfd = socket(af, SOCK_STREAM, 0);
     if (sockfd == INVALID_SOCKET) {
       Socket::Error("Create");
     }

src/runtime/rpc/rpc_socket_impl.cc

@@ -43,7 +43,7 @@ std::shared_ptr<RPCSession>
 RPCConnect(std::string url, int port, std::string key) {
   common::TCPSocket sock;
   common::SockAddr addr(url.c_str(), port);
-  sock.Create();
+  sock.Create(addr.ss_family());
   CHECK(sock.Connect(addr))
       << "Connect to " << addr.AsString() << " failed";
   // hand shake