eal: close multi-process socket during cleanup

When secondary process quit, the mp_socket* file still exist, that
cause rte_mp_request_sync fail when try to send message on a floating
socket.

The patch fix the issue by introduce a function rte_mp_channel_cleanup.
This function will be called by rte_eal_cleanup and it will close the
mp socket and delete the mp_socket* file.

Fixes: bacaa2754017 ("eal: add channel for multi-process communication")
Cc: stable@dpdk.org

Signed-off-by: Qi Zhang <qi.z.zhang@intel.com>

lib/librte_eal/bsdapp/eal/eal.c

@@ -922,6 +922,7 @@ int __rte_experimental
 rte_eal_cleanup(void)
 {
 	rte_service_finalize();
+	rte_mp_channel_cleanup();
 	return 0;
 }
 

lib/librte_eal/common/eal_common_proc.c

@@ -37,6 +37,7 @@ static int mp_fd = -1;
 static char mp_filter[PATH_MAX];   /* Filter for secondary process sockets */
 static char mp_dir_path[PATH_MAX]; /* The directory path for all mp sockets */
 static pthread_mutex_t mp_mutex_action = PTHREAD_MUTEX_INITIALIZER;
+static char peer_name[PATH_MAX];
 
 struct action_entry {
 	TAILQ_ENTRY(action_entry) next;
@@ -511,9 +512,9 @@ async_reply_handle(void *arg)
 static int
 open_socket_fd(void)
 {
-	char peer_name[PATH_MAX] = {0};
 	struct sockaddr_un un;
 
+	peer_name[0] = '\0';
 	if (rte_eal_process_type() == RTE_PROC_SECONDARY)
 		snprintf(peer_name, sizeof(peer_name),
 				"%d_%"PRIx64, getpid(), rte_rdtsc());
@@ -542,6 +543,19 @@ open_socket_fd(void)
 	return mp_fd;
 }
 
+static void
+close_socket_fd(void)
+{
+	char path[PATH_MAX];
+
+	if (mp_fd < 0)
+		return;
+
+	close(mp_fd);
+	create_socket_path(peer_name, path, sizeof(path));
+	unlink(path);
+}
+
 int
 rte_mp_channel_init(void)
 {
@@ -602,6 +616,12 @@ rte_mp_channel_init(void)
 	return 0;
 }
 
+void
+rte_mp_channel_cleanup(void)
+{
+	close_socket_fd();
+}
+
 /**
  * Return -1, as fail to send message and it's caused by the local side.
  * Return 0, as fail to send message and it's caused by the remote side.

lib/librte_eal/common/eal_private.h

@@ -255,9 +255,13 @@ struct rte_bus *rte_bus_find_by_device_name(const char *str);
  *   0 on success;
  *   (<0) on failure.
  */
-
 int rte_mp_channel_init(void);
 
+/**
+ * Primary/secondary communication cleanup.
+ */
+void rte_mp_channel_cleanup(void);
+
 /**
  * @internal
  * Parse a device string and store its information in an

lib/librte_eal/linuxapp/eal/eal.c

@@ -1237,6 +1237,7 @@ rte_eal_cleanup(void)
 	if (rte_eal_process_type() == RTE_PROC_PRIMARY)
 		rte_memseg_walk(mark_freeable, NULL);
 	rte_service_finalize();
+	rte_mp_channel_cleanup();
 	return 0;
 }