- reuseport is attempted, then fallback to without on failure.

git-svn-id: file:///svn/unbound/trunk@3054 be551aaa-1e26-0410-a405-d3ace91eadb9

daemon/daemon.c

@@ -256,32 +256,52 @@ daemon_open_shared_ports(struct daemon* daemon)
 	log_assert(daemon);
 	if(daemon->cfg->port != daemon->listening_port) {
 		size_t i;
-#if defined(__linux__) && defined(SO_REUSEPORT)
-		if(daemon->cfg->so_reuseport && daemon->cfg->num_threads > 0)
-			daemon->num_ports = daemon->cfg->num_threads;
-		else
-			daemon->num_ports = 1;
-#else
-		daemon->num_ports = 1;
-#endif
+		int reuseport = 0;
+		struct listen_port* p0;
+		/* free and close old ports */
 		if(daemon->ports != NULL) {
 			for(i=0; i<daemon->num_ports; i++)
 				listening_ports_free(daemon->ports[i]);
 			free(daemon->ports);
 			daemon->ports = NULL;
 		}
-		if(!(daemon->ports = (struct listen_port**)calloc(
-			daemon->num_ports, sizeof(*daemon->ports)))) {
+		/* see if we want to reuseport */
+#if defined(__linux__) && defined(SO_REUSEPORT)
+		if(daemon->cfg->so_reuseport && daemon->cfg->num_threads > 0)
+			reuseport = 1;
+#endif
+		/* try to use reuseport */
+		p0 = listening_ports_open(daemon->cfg, &reuseport);
+		if(!p0) {
+			listening_ports_free(p0);
 			return 0;
 		}
-		for(i=0; i<daemon->num_ports; i++) {
-			if(!(daemon->ports[i]=
-				listening_ports_open(daemon->cfg))) {
-				for(i=0; i<daemon->num_ports; i++)
-					listening_ports_free(daemon->ports[i]);
-				free(daemon->ports);
-				daemon->ports = NULL;
-				return 0;
+		if(reuseport) {
+			/* reuseport was successful, allocate for it */
+			daemon->num_ports = daemon->cfg->num_threads;
+		} else {
+			/* do the normal, singleportslist thing,
+			 * reuseport not enabled or did not work */
+			daemon->num_ports = 1;
+		}
+		if(!(daemon->ports = (struct listen_port**)calloc(
+			daemon->num_ports, sizeof(*daemon->ports)))) {
+			listening_ports_free(p0);
+			return 0;
+		}
+		daemon->ports[0] = p0;
+		if(reuseport) {
+			/* continue to use reuseport */
+			for(i=1; i<daemon->num_ports; i++) {
+				if(!(daemon->ports[i]=
+					listening_ports_open(daemon->cfg,
+						&reuseport)) || !reuseport ) {
+					for(i=0; i<daemon->num_ports; i++)
+						listening_ports_free(daemon->ports[i]);
+					free(daemon->ports);
+					daemon->ports = NULL;
+					return 0;
+				}
 			}
 		}
 		daemon->listening_port = daemon->cfg->port;

doc/Changelog

@@ -1,3 +1,6 @@
+27 January 2014: Wouter
+	- reuseport is attempted, then fallback to without on failure.
+
 24 January 2014: Wouter
 	- Change unbound-event.h to use void* buffer, length idiom.
 	- iana portlist updated.

doc/unbound.conf.5.in

@@ -254,7 +254,10 @@ to so\-rcvbuf.
 If yes, then open dedicated listening sockets for incoming queries for each
 thread and try to set the SO_REUSEPORT socket option on each socket.  May
 distribute incoming queries to threads more evenly.  Default is no.  Only
-supported on Linux >= 3.9.
+supported on Linux >= 3.9.  You can enable it (on any platform and kernel),
+it then attempts to open the port and passes the option if it was available
+at compile time, if that works it is used, if it fails, it continues
+silently (unless verbosity 3) without the option.
 .TP
 .B rrset\-cache\-size: \fI<number>
 Number of bytes size of the RRset cache. Default is 4 megabytes.

services/listen_dnsport.c

@@ -92,7 +92,7 @@ verbose_print_addr(struct addrinfo *addr)
 int
 create_udp_sock(int family, int socktype, struct sockaddr* addr,
         socklen_t addrlen, int v6only, int* inuse, int* noproto,
-	int rcv, int snd, int listen, int reuseport)
+	int rcv, int snd, int listen, int* reuseport)
 {
 	int s;
 #if defined(SO_REUSEADDR) || defined(SO_REUSEPORT) || defined(IPV6_USE_MIN_MTU)
@@ -154,15 +154,16 @@ create_udp_sock(int family, int socktype, struct sockaddr* addr,
 		 * Each thread must have its own socket bound to the same port,
 		 * with SO_REUSEPORT set on each socket.
 		 */
-		if (reuseport &&
+		if (reuseport && *reuseport &&
 		    setsockopt(s, SOL_SOCKET, SO_REUSEPORT, (void*)&on,
 			(socklen_t)sizeof(on)) < 0) {
-			log_err("setsockopt(.. SO_REUSEPORT ..) failed: %s",
-				strerror(errno));
-			close(s);
-			*noproto = 0;
-			*inuse = 0;
-			return -1;
+#ifdef ENOPROTOOPT
+			if(errno != ENOPROTOOPT || verbosity >= 3)
+				log_warn("setsockopt(.. SO_REUSEPORT ..) failed: %s",
+					strerror(errno));
+#endif
+			/* this option is not essential, we can continue */
+			*reuseport = 0;
 		}
 #else
 		(void)reuseport;
@@ -431,7 +432,7 @@ create_udp_sock(int family, int socktype, struct sockaddr* addr,
 
 int
 create_tcp_accept_sock(struct addrinfo *addr, int v6only, int* noproto,
-	int reuseport)
+	int* reuseport)
 {
 	int s;
 #if defined(SO_REUSEADDR) || defined(SO_REUSEPORT) || defined(IPV6_V6ONLY)
@@ -478,12 +479,16 @@ create_tcp_accept_sock(struct addrinfo *addr, int v6only, int* noproto,
 	 * Each thread must have its own socket bound to the same port,
 	 * with SO_REUSEPORT set on each socket.
 	 */
-	if (reuseport && setsockopt(s, SOL_SOCKET, SO_REUSEPORT, (void*)&on,
+	if (reuseport && *reuseport &&
+		setsockopt(s, SOL_SOCKET, SO_REUSEPORT, (void*)&on,
 		(socklen_t)sizeof(on)) < 0) {
-		log_err("setsockopt(.. SO_REUSEPORT ..) failed: %s",
-			strerror(errno));
-		close(s);
-		return -1;
+#ifdef ENOPROTOOPT
+		if(errno != ENOPROTOOPT || verbosity >= 3)
+			log_warn("setsockopt(.. SO_REUSEPORT ..) failed: %s",
+				strerror(errno));
+#endif
+		/* this option is not essential, we can continue */
+		*reuseport = 0;
 	}
 #else
 	(void)reuseport;
@@ -556,7 +561,7 @@ create_tcp_accept_sock(struct addrinfo *addr, int v6only, int* noproto,
 static int
 make_sock(int stype, const char* ifname, const char* port, 
 	struct addrinfo *hints, int v6only, int* noip6, size_t rcv, size_t snd,
-	int reuseport)
+	int* reuseport)
 {
 	struct addrinfo *res = NULL;
 	int r, s, inuse, noproto;
@@ -604,7 +609,7 @@ make_sock(int stype, const char* ifname, const char* port,
 static int
 make_sock_port(int stype, const char* ifname, const char* port, 
 	struct addrinfo *hints, int v6only, int* noip6, size_t rcv, size_t snd,
-	int reuseport)
+	int* reuseport)
 {
 	char* s = strchr(ifname, '@');
 	if(s) {
@@ -721,13 +726,14 @@ set_recvpktinfo(int s, int family)
  * @param rcv: receive buffer size for UDP
  * @param snd: send buffer size for UDP
  * @param ssl_port: ssl service port number
- * @param reuseport: try to set SO_REUSEPORT.
+ * @param reuseport: try to set SO_REUSEPORT if nonNULL and true.
+ * 	set to false on exit if reuseport failed due to no kernel support.
  * @return: returns false on error.
  */
 static int
 ports_create_if(const char* ifname, int do_auto, int do_udp, int do_tcp, 
 	struct addrinfo *hints, const char* port, struct listen_port** list,
-	size_t rcv, size_t snd, int ssl_port, int reuseport)
+	size_t rcv, size_t snd, int ssl_port, int* reuseport)
 {
 	int s, noip6=0;
 	if(!do_udp && !do_tcp)
@@ -901,7 +907,7 @@ listen_delete(struct listen_dnsport* front)
 }
 
 struct listen_port* 
-listening_ports_open(struct config_file* cfg)
+listening_ports_open(struct config_file* cfg, int* reuseport)
 {
 	struct listen_port* list = NULL;
 	struct addrinfo hints;
@@ -937,7 +943,7 @@ listening_ports_open(struct config_file* cfg)
 				do_auto, cfg->do_udp, do_tcp, 
 				&hints, portbuf, &list,
 				cfg->so_rcvbuf, cfg->so_sndbuf,
-				cfg->ssl_port, cfg->so_reuseport)) {
+				cfg->ssl_port, reuseport)) {
 				listening_ports_free(list);
 				return NULL;
 			}
@@ -948,7 +954,7 @@ listening_ports_open(struct config_file* cfg)
 				do_auto, cfg->do_udp, do_tcp, 
 				&hints, portbuf, &list,
 				cfg->so_rcvbuf, cfg->so_sndbuf,
-				cfg->ssl_port, cfg->so_reuseport)) {
+				cfg->ssl_port, reuseport)) {
 				listening_ports_free(list);
 				return NULL;
 			}
@@ -961,7 +967,7 @@ listening_ports_open(struct config_file* cfg)
 			if(!ports_create_if(cfg->ifs[i], 0, cfg->do_udp, 
 				do_tcp, &hints, portbuf, &list, 
 				cfg->so_rcvbuf, cfg->so_sndbuf,
-				cfg->ssl_port, cfg->so_reuseport)) {
+				cfg->ssl_port, reuseport)) {
 				listening_ports_free(list);
 				return NULL;
 			}
@@ -972,7 +978,7 @@ listening_ports_open(struct config_file* cfg)
 			if(!ports_create_if(cfg->ifs[i], 0, cfg->do_udp, 
 				do_tcp, &hints, portbuf, &list, 
 				cfg->so_rcvbuf, cfg->so_sndbuf,
-				cfg->ssl_port, cfg->so_reuseport)) {
+				cfg->ssl_port, reuseport)) {
 				listening_ports_free(list);
 				return NULL;
 			}

services/listen_dnsport.h

@@ -107,9 +107,13 @@ struct listen_port {
  * interfaces for IP4 and/or IP6, for UDP and/or TCP.
  * On the given port number. It creates the sockets.
  * @param cfg: settings on what ports to open.
+ * @param reuseport: set to true if you want reuseport, or NULL to not have it,
+ *   set to false on exit if reuseport failed to apply (because of no
+ *   kernel support).
  * @return: linked list of ports or NULL on error.
  */
-struct listen_port* listening_ports_open(struct config_file* cfg);
+struct listen_port* listening_ports_open(struct config_file* cfg,
+	int* reuseport);
 
 /**
  * Close and delete the (list of) listening ports.
@@ -181,22 +185,24 @@ void listen_start_accept(struct listen_dnsport* listen);
  * @param snd: set size on sndbuf with socket option, if 0 it is not set.
  * @param listen: if true, this is a listening UDP port, eg port 53, and 
  * 	set SO_REUSEADDR on it.
- * @param reuseport: if true, try to set SO_REUSEPORT on listening UDP port.
+ * @param reuseport: if nonNULL and true, try to set SO_REUSEPORT on
+ * 	listening UDP port.  Set to false on return if it failed to do so.
  * @return: the socket. -1 on error.
  */
 int create_udp_sock(int family, int socktype, struct sockaddr* addr, 
 	socklen_t addrlen, int v6only, int* inuse, int* noproto, int rcv,
-	int snd, int listen, int reuseport);
+	int snd, int listen, int* reuseport);
 
 /**
  * Create and bind TCP listening socket
  * @param addr: address info ready to make socket.
  * @param v6only: enable ip6 only flag on ip6 sockets.
  * @param noproto: if error caused by lack of protocol support.
- * @param reuseport: if true, try to set SO_REUSEPORT.
+ * @param reuseport: if nonNULL and true, try to set SO_REUSEPORT on
+ * 	listening UDP port.  Set to false on return if it failed to do so.
  * @return: the socket. -1 on error.
  */
 int create_tcp_accept_sock(struct addrinfo *addr, int v6only, int* noproto,
-	int reuseport);
+	int* reuseport);
 
 #endif /* LISTEN_DNSPORT_H */

services/outside_network.c

@@ -849,13 +849,13 @@ udp_sockport(struct sockaddr_storage* addr, socklen_t addrlen, int port,
 		sa->sin6_port = (in_port_t)htons((uint16_t)port);
 		fd = create_udp_sock(AF_INET6, SOCK_DGRAM, 
 			(struct sockaddr*)addr, addrlen, 1, inuse, &noproto,
-			0, 0, 0, 0);
+			0, 0, 0, NULL);
 	} else {
 		struct sockaddr_in* sa = (struct sockaddr_in*)addr;
 		sa->sin_port = (in_port_t)htons((uint16_t)port);
 		fd = create_udp_sock(AF_INET, SOCK_DGRAM, 
 			(struct sockaddr*)addr, addrlen, 1, inuse, &noproto,
-			0, 0, 0, 0);
+			0, 0, 0, NULL);
 	}
 	return fd;
 }

testcode/fake_event.c

@@ -1142,7 +1142,8 @@ void outnet_serviced_query_stop(struct serviced_query* sq, void* cb_arg)
 	log_info("double delete of pending serviced query");
 }
 
-struct listen_port* listening_ports_open(struct config_file* ATTR_UNUSED(cfg))
+struct listen_port* listening_ports_open(struct config_file* ATTR_UNUSED(cfg),
+	int* ATTR_UNUSED(reuseport))
 {
 	return calloc(1, 1);
 }