issue: 601270 optimize accept() call

1. do poll OS only if bound to any address
2. do one CQ poll and go to sleep (unless infinite polling was set)

TODO:
1. do one CQ poll and go to sleep even if infinite polling was set
2. do poll OS only if waken-up by OS fd

Change-Id: Ifab922f1323fca202bf4d09813bd939d38d57161
Signed-off-by: Or Kehati <[email protected]>

src/vma/sock/sockinfo_tcp.cpp

@@ -2031,7 +2031,8 @@ int sockinfo_tcp::listen(int backlog)
 int sockinfo_tcp::accept_helper(struct sockaddr *__addr, socklen_t *__addrlen, int __flags /* = 0 */)
 {
 	sockinfo_tcp *ns;
-	int poll_count = 0;
+	//todo do one CQ poll and go to sleep even if infinite polling was set
+	int poll_count = mce_sys.rx_poll_num; //do one poll and go to sleep (if blocking)
 	int ret;
 
 	si_tcp_logfuncall("");
@@ -2063,25 +2064,29 @@ int sockinfo_tcp::accept_helper(struct sockaddr *__addr, socklen_t *__addrlen, i
 			errno = EINVAL;
 			return -1;
 		}
-		// Poll OS socket for pending connection
-		// smart bit to switch between the two
-		pollfd os_fd[1];
-		os_fd[0].fd = m_fd;
-		os_fd[0].events = POLLIN;
-		ret = orig_os_api.poll(os_fd, 1, 0); // Zero timeout - just poll and return quickly
-		if (unlikely(ret == -1)) {
-			m_p_socket_stats->counters.n_rx_os_errors++;
-			si_tcp_logdbg("orig_os_api.poll returned with error (errno=%d %m)", errno);
-			unlock_tcp_con();
-			return -1;
-		}
-		if (ret == 1) {
-			si_tcp_logdbg("orig_os_api.poll returned with packet");
-			unlock_tcp_con();
-			if (__flags)
-				return orig_os_api.accept4(m_fd, __addr, __addrlen, __flags);
-			else
-				return orig_os_api.accept(m_fd, __addr, __addrlen);
+
+		//todo instead of doing blind poll, check if waken-up by OS fd in rx_wait
+		if (m_bound.is_anyaddr()) {
+			// Poll OS socket for pending connection
+			// smart bit to switch between the two
+			pollfd os_fd[1];
+			os_fd[0].fd = m_fd;
+			os_fd[0].events = POLLIN;
+			ret = orig_os_api.poll(os_fd, 1, 0); // Zero timeout - just poll and return quickly
+			if (unlikely(ret == -1)) {
+				m_p_socket_stats->counters.n_rx_os_errors++;
+				si_tcp_logdbg("orig_os_api.poll returned with error (errno=%d %m)", errno);
+				unlock_tcp_con();
+				return -1;
+			}
+			if (ret == 1) {
+				si_tcp_logdbg("orig_os_api.poll returned with packet");
+				unlock_tcp_con();
+				if (__flags)
+					return orig_os_api.accept4(m_fd, __addr, __addrlen, __flags);
+				else
+					return orig_os_api.accept(m_fd, __addr, __addrlen);
+			}
 		}
 
 		if (rx_wait(poll_count, m_b_blocking) < 0) {