tcp, tap: Turn tcp_probe_mem() into sock_probe_mem(), use for AF_UNIX socket too

Signed-off-by: Stefano Brivio <sbrivio@redhat.com>

passt.c

@@ -374,6 +374,7 @@ int main(int argc, char **argv)
 		perror("setrlimit");
 		exit(EXIT_FAILURE);
 	}
+	sock_probe_mem(&c);
 
 	proto_update_l2_buf(c.mac_guest, c.mac, &c.addr4);
 

passt.h

@@ -126,6 +126,8 @@ enum passt_modes {
  * @no_dhcpv6:		Disable DHCPv6 server
  * @no_ndp:		Disable NDP handler altogether
  * @no_ra:		Disable router advertisements
+ * @low_wmem:		Low probed net.core.wmem_max
+ * @low_rmem:		Low probed net.core.rmem_max
  */
 struct ctx {
 	enum passt_modes mode;
@@ -177,6 +179,9 @@ struct ctx {
 	int no_dhcpv6;
 	int no_ndp;
 	int no_ra;
+
+	int low_wmem;
+	int low_rmem;
 };
 
 void proto_update_l2_buf(unsigned char *eth_d, unsigned char *eth_s,

tap.c

@@ -773,7 +773,7 @@ static void tap_sock_init_unix(struct ctx *c)
 	struct sockaddr_un addr = {
 		.sun_family = AF_UNIX,
 	};
-	int i, ret;
+	int i, ret, v = INT_MAX / 2;
 
 	if (c->fd_tap_listen)
 		close(c->fd_tap_listen);
@@ -833,6 +833,12 @@ static void tap_sock_init_unix(struct ctx *c)
 	     addr.sun_path);
 
 	c->fd_tap = accept(fd, NULL, NULL);
+
+	if (!c->low_rmem)
+		setsockopt(c->fd_tap, SOL_SOCKET, SO_RCVBUF, &v, sizeof(v));
+
+	if (!c->low_wmem)
+		setsockopt(c->fd_tap, SOL_SOCKET, SO_SNDBUF, &v, sizeof(v));
 }
 
 static int tun_ns_fd = -1;

tcp.c

@@ -341,9 +341,6 @@
 
 #define TCP_TAP_FRAMES			32
 
-#define RCVBUF_BIG			(2 * 1024 * 1024)
-#define SNDBUF_BIG			(2 * 1024 * 1024)
-#define SNDBUF_SMALL			(128 * 1024)
 #define MAX_PIPE_SIZE			(2 * 1024 * 1024)
 
 #define TCP_HASH_TABLE_LOAD		70		/* % */
@@ -753,33 +750,6 @@ static void tcp_splice_state(struct tcp_splice_conn *conn, enum tcp_state state)
 	conn->state = state;
 }
 
-/**
- * tcp_probe_mem() - Check if setting high SO_SNDBUF and SO_RCVBUF is allowed
- * @c:		Execution context
- */
-static void tcp_probe_mem(struct ctx *c)
-{
-	int v = INT_MAX / 2, s;
-	socklen_t sl;
-
-	if ((s = socket(AF_INET, SOCK_STREAM, IPPROTO_TCP)) < 0) {
-		c->tcp.low_wmem = c->tcp.low_rmem = 1;
-		return;
-	}
-
-	sl = sizeof(v);
-	if (setsockopt(s, SOL_SOCKET, SO_SNDBUF, &v, sizeof(v))	||
-	    getsockopt(s, SOL_SOCKET, SO_SNDBUF, &v, &sl) || v < SNDBUF_BIG)
-		c->tcp.low_wmem = 1;
-
-	v = INT_MAX / 2;
-	if (setsockopt(s, SOL_SOCKET, SO_RCVBUF, &v, sizeof(v))	||
-	    getsockopt(s, SOL_SOCKET, SO_RCVBUF, &v, &sl) || v < RCVBUF_BIG)
-		c->tcp.low_rmem = 1;
-
-	close(s);
-}
-
 /**
  * tcp_get_sndbuf() - Get, scale SO_SNDBUF between thresholds (1 to 0.5 usage)
  * @conn:	Connection pointer
@@ -814,10 +784,10 @@ static void tcp_sock_set_bufsize(struct ctx *c, int s)
 	if (s == -1)
 		return;
 
-	if (!c->tcp.low_rmem)
+	if (!c->low_rmem)
 		setsockopt(s, SOL_SOCKET, SO_RCVBUF, &v, sizeof(v));
 
-	if (!c->tcp.low_wmem)
+	if (!c->low_wmem)
 		setsockopt(s, SOL_SOCKET, SO_SNDBUF, &v, sizeof(v));
 }
 
@@ -1325,7 +1295,7 @@ static int tcp_send_to_tap(struct ctx *c, struct tcp_tap_conn *conn, int flags,
 			else
 				mss -= sizeof(struct ipv6hdr);
 
-			if (c->tcp.low_wmem &&
+			if (c->low_wmem &&
 			    !conn->local && !tcp_rtt_dst_low(conn))
 				mss = MIN(mss, PAGE_SIZE);
 			else
@@ -3342,8 +3312,6 @@ int tcp_sock_init(struct ctx *c, struct timespec *now)
 
 	getrandom(&c->tcp.hash_secret, sizeof(c->tcp.hash_secret), GRND_RANDOM);
 
-	tcp_probe_mem(c);
-
 	for (port = 0; port < USHRT_MAX; port++) {
 		if (!bitmap_isset(c->tcp.port_to_tap, port))
 			continue;

tcp.h

@@ -51,8 +51,6 @@ union tcp_epoll_ref {
  * @pipe_size:		Size of pipes for spliced connections
  * @refill_ts:		Time of last refill operation for pools of sockets/pipes
  * @port_detect_ts:	Time of last TCP port detection/rebind, if enabled
- * @low_wmem:		Low probed net.core.wmem_max
- * @low_rmem:		Low probed net.core.rmem_max
  */
 struct tcp_ctx {
 	uint64_t hash_secret[2];
@@ -67,8 +65,6 @@ struct tcp_ctx {
 	size_t pipe_size;
 	struct timespec refill_ts;
 	struct timespec port_detect_ts;
-	int low_wmem;
-	int low_rmem;
 };
 
 #endif /* TCP_H */

util.c

@@ -212,6 +212,34 @@ int sock_l4(struct ctx *c, int af, uint8_t proto, uint16_t port,
 	return fd;
 }
 
+/**
+ * sock_probe_mem() - Check if setting high SO_SNDBUF and SO_RCVBUF is allowed
+ * @c:		Execution context
+ */
+void sock_probe_mem(struct ctx *c)
+{
+	int v = INT_MAX / 2, s;
+	socklen_t sl;
+
+	if ((s = socket(AF_INET, SOCK_STREAM, IPPROTO_TCP)) < 0) {
+		c->low_wmem = c->low_rmem = 1;
+		return;
+	}
+
+	sl = sizeof(v);
+	if (setsockopt(s, SOL_SOCKET, SO_SNDBUF, &v, sizeof(v))	||
+	    getsockopt(s, SOL_SOCKET, SO_SNDBUF, &v, &sl) || v < SNDBUF_BIG)
+		c->low_wmem = 1;
+
+	v = INT_MAX / 2;
+	if (setsockopt(s, SOL_SOCKET, SO_RCVBUF, &v, sizeof(v))	||
+	    getsockopt(s, SOL_SOCKET, SO_RCVBUF, &v, &sl) || v < RCVBUF_BIG)
+		c->low_rmem = 1;
+
+	close(s);
+}
+
+
 /**
  * timespec_diff_ms() - Report difference in milliseconds between two timestamps
  * @a:		Minuend timestamp

util.h

@@ -116,6 +116,10 @@ void debug(const char *format, ...);
 		.daddr		= IN6ADDR_ANY_INIT,			\
 	}
 
+#define RCVBUF_BIG		(2 * 1024 * 1024)
+#define SNDBUF_BIG		(4 * 1024 * 1024)
+#define SNDBUF_SMALL		(128 * 1024)
+
 #include <linux/ipv6.h>
 #include <net/if.h>
 #include <linux/ip.h>
@@ -133,6 +137,7 @@ struct ctx;
 char *ipv6_l4hdr(struct ipv6hdr *ip6h, uint8_t *proto);
 int sock_l4(struct ctx *c, int af, uint8_t proto, uint16_t port,
 	    enum bind_type bind_addr, uint32_t data);
+void sock_probe_mem(struct ctx *c);
 int timespec_diff_ms(struct timespec *a, struct timespec *b);
 void bitmap_set(uint8_t *map, int bit);
 void bitmap_clear(uint8_t *map, int bit);