Move function to more logical place.

SendDummyPacket() is completely specific to the UDP interconnect
implementation.

Along the way, I couldn't resist some cosmetic cleanup: use %m rather than
strerror(errno), avoid unnecessary variable initializations, and pgindent.

src/backend/cdb/motion/ic_common.c

@@ -793,114 +793,6 @@ void adjustMasterRouting(Slice *recvSlice)
 	}
 }
 
-void
-SendDummyPacket(void)
-{
-	int sockfd = -1;
-	int ret = -1;
-	struct addrinfo* addrs = NULL;
-	struct addrinfo* rp = NULL;
-	struct addrinfo hint;
-	uint16 udp_listener;
-	char	port_str[32] = {0};
-	char* dummy_pkt = "stop it";
-
-	/*
-	 * Get address info from interconnect udp listener port
-	 */
-	udp_listener = Gp_listener_port;
-	snprintf(port_str, sizeof(port_str), "%d", udp_listener);
-
-	MemSet(&hint, 0, sizeof(hint));
-	hint.ai_socktype = SOCK_DGRAM;
-	hint.ai_family = AF_UNSPEC; /* Allow for IPv4 or IPv6  */
-
-#ifdef AI_NUMERICSERV
-	hint.ai_flags = AI_NUMERICHOST | AI_NUMERICSERV;  /* Never do name resolution */
-#else
-	hint.ai_flags = AI_NUMERICHOST;  /* Never do name resolution */
-#endif
-
-	ret = pg_getaddrinfo_all(NULL, port_str, &hint, &addrs);
-	if (ret || !addrs)
-	{
-		elog(LOG, "Send dummy packet failed, pg_getaddrinfo_all(): %s", strerror(errno));
-		goto send_error;
-	}
-
-	for (rp = addrs; rp != NULL; rp = rp->ai_next)
-	{
-		/* Create socket according to pg_getaddrinfo_all() */
-		sockfd = socket(rp->ai_family, rp->ai_socktype, rp->ai_protocol);
-		if (sockfd < 0)
-		{
-			continue;
-		}
-
-		if (!pg_set_noblock(sockfd))
-		{
-			if (sockfd >= 0)
-			{
-				closesocket(sockfd);
-				sockfd = -1;
-			}
-			continue;
-		}
-		break;
-	}
-
-	if (rp == NULL)
-	{
-		elog(LOG, "Send dummy packet failed, create socket failed: %s", strerror(errno));
-		goto send_error;
-	}
-
-	/*
-	 * Send a dummy package to the interconnect listener, try 10 times
-	 */
-	int counter = 0;
-	while (counter < 10)
-	{
-		counter++;
-		ret = sendto(sockfd, dummy_pkt, strlen(dummy_pkt), 0, rp->ai_addr, rp->ai_addrlen);
-		if (ret < 0)
-		{
-			if (errno == EINTR || errno == EAGAIN || errno == EWOULDBLOCK)
-			{
-				continue;
-			}
-			else
-			{
-				elog(LOG, "Send dummy packet failed, sendto failed: %s", strerror(errno));
-				goto send_error;
-			}
-		}
-		break;
-	}
-
-	if (counter >= 10)
-	{
-		elog(LOG, "Send dummy packet failed, sendto failed: %s", strerror(errno));
-		goto send_error;
-	}
-
-	pg_freeaddrinfo_all(hint.ai_family, addrs);
-	closesocket(sockfd);
-	return;
-
-send_error:
-
-	if (addrs)
-	{
-		pg_freeaddrinfo_all(hint.ai_family, addrs);
-	}
-	if (sockfd != -1)
-	{
-		closesocket(sockfd);
-	}
-	return;
-}
-
 /*
 * WaitInterconnectQuit
 *

src/backend/cdb/motion/ic_udpifc.c

@@ -643,6 +643,7 @@ static void setMainThreadWaiting(ThreadWaitingState *state, int motNodeId, int r
 static void checkRxThreadError(void);
 static void setRxThreadError(int eno);
 static void resetRxThreadError(void);
+static void SendDummyPacket(void);
 
 static void getSockAddr(struct sockaddr_storage * peer, socklen_t * peer_len, const char * listenerAddr, int listenerPort);
 static void setXmitSocketOptions(int txfd);
@@ -6686,3 +6687,109 @@ WaitInterconnectQuitUDPIFC(void)
 	}
 	ic_control_info.threadCreated = false;
 }
+
+/*
+ * Send a dummy packet to interconnect thread to exit poll() immediately
+ */
+static void
+SendDummyPacket(void)
+{
+	int			sockfd = -1;
+	int			ret;
+	struct addrinfo *addrs = NULL;
+	struct addrinfo *rp;
+	struct addrinfo hint;
+	uint16		udp_listener;
+	char		port_str[32] = {0};
+	char	   *dummy_pkt = "stop it";
+	int			counter;
+
+	/*
+	 * Get address info from interconnect udp listener port
+	 */
+	udp_listener = Gp_listener_port;
+	snprintf(port_str, sizeof(port_str), "%d", udp_listener);
+
+	MemSet(&hint, 0, sizeof(hint));
+	hint.ai_socktype = SOCK_DGRAM;
+	hint.ai_family = AF_UNSPEC; /* Allow for IPv4 or IPv6  */
+
+	/* Never do name resolution */
+#ifdef AI_NUMERICSERV
+	hint.ai_flags = AI_NUMERICHOST | AI_NUMERICSERV;
+#else
+	hint.ai_flags = AI_NUMERICHOST;
+#endif
+
+	ret = pg_getaddrinfo_all(NULL, port_str, &hint, &addrs);
+	if (ret || !addrs)
+	{
+		elog(LOG, "send dummy packet failed, pg_getaddrinfo_all(): %m");
+		goto send_error;
+	}
+
+	for (rp = addrs; rp != NULL; rp = rp->ai_next)
+	{
+		/* Create socket according to pg_getaddrinfo_all() */
+		sockfd = socket(rp->ai_family, rp->ai_socktype, rp->ai_protocol);
+		if (sockfd < 0)
+			continue;
+
+		if (!pg_set_noblock(sockfd))
+		{
+			if (sockfd >= 0)
+			{
+				closesocket(sockfd);
+				sockfd = -1;
+			}
+			continue;
+		}
+		break;
+	}
+
+	if (rp == NULL)
+	{
+		elog(LOG, "send dummy packet failed, create socket failed: %m");
+		goto send_error;
+	}
+
+	/*
+	 * Send a dummy package to the interconnect listener, try 10 times
+	 */
+
+	counter = 0;
+	while (counter < 10)
+	{
+		counter++;
+		ret = sendto(sockfd, dummy_pkt, strlen(dummy_pkt), 0, rp->ai_addr, rp->ai_addrlen);
+		if (ret < 0)
+		{
+			if (errno == EINTR || errno == EAGAIN || errno == EWOULDBLOCK)
+				continue;
+			else
+			{
+				elog(LOG, "send dummy packet failed, sendto failed: %m");
+				goto send_error;
+			}
+		}
+		break;
+	}
+
+	if (counter >= 10)
+	{
+		elog(LOG, "send dummy packet failed, sendto failed: %m");
+		goto send_error;
+	}
+
+	pg_freeaddrinfo_all(hint.ai_family, addrs);
+	closesocket(sockfd);
+	return;
+
+send_error:
+
+	if (addrs)
+		pg_freeaddrinfo_all(hint.ai_family, addrs);
+	if (sockfd != -1)
+		closesocket(sockfd);
+	return;
+}

src/include/cdb/ml_ipc.h

@@ -50,11 +50,6 @@ extern void CleanUpMotionLayerIPC(void);
  */
 extern void WaitInterconnectQuit(void);
 
-/*
-* Send a dummy packet to interconnect thread to exit poll() immediately
-*/
-extern void SendDummyPacket(void);
-
 /* Returns the fd of the socket that connects to the seqserver.  This value
  * is -1 if it has not been setup.
  */