issue: 3586273 Use XLIO_DEFERRED_CLOSE by default

For incoming sockets - no change.
For outgoing sockets - since outgoing sockets occupy a local port, we
should release it on the socket destructor to prevent race from another
socket to use the same port.
This race might cause XLIO to hold 2 sockets with the same RFS object at
the same time, and this is fatal (particularly for TCP).

Signed-off-by: Iftah Levi <[email protected]>

Author: iftahl

src/core/sock/sock-redirect.cpp

@@ -253,15 +253,13 @@ bool handle_close(int fd, bool cleanup, bool passthrough)
         sockinfo *sockfd = fd_collection_get_sockfd(fd);
         if (sockfd) {
             // Don't call close(2) for objects without a shadow socket (TCP incoming sockets).
-            to_close_now = !passthrough && sockfd->is_shadow_socket_present();
+            to_close_now = !safe_mce_sys().deferred_close && !passthrough &&
+                sockfd->is_shadow_socket_present();
 #if defined(DEFINED_NGINX)
             // Save this value before pointer is destructed
             is_for_udp_pool = sockfd->m_is_for_socket_pool;
 #endif
             g_p_fd_collection->del_sockfd(fd, is_for_udp_pool);
-            if (safe_mce_sys().deferred_close) {
-                to_close_now = false;
-            }
         }
         if (fd_collection_get_epfd(fd)) {
             g_p_fd_collection->del_epfd(fd, cleanup);

src/core/util/sys_vars.h

@@ -872,7 +872,7 @@ extern mce_sys_var &safe_mce_sys();
 #endif /* DEFINED_UTLS */
 
 #define MCE_DEFAULT_LRO                            (option_3::AUTO)
-#define MCE_DEFAULT_DEFERRED_CLOSE                 (false)
+#define MCE_DEFAULT_DEFERRED_CLOSE                 (true)
 #define MCE_DEFAULT_TCP_ABORT_ON_CLOSE             (false)
 #define MCE_DEFAULT_RX_POLL_ON_TX_TCP              (false)
 #define MCE_DEFAULT_TRIGGER_DUMMY_SEND_GETSOCKNAME (false)