examples/l2fwd-keepalive: add graceful exit

The l2fwd-keepalive example has infinite processing loops and as a
result the only way to exit it is via SIGINT/SIGTERM (e.g. Control-C).
The resulting shutdown is unclean, which is fixed by adding a signal
handler that causes the processing loops to break.

Fixes: e64833f2273a ("examples/l2fwd-keepalive: add sample application")

Signed-off-by: Remy Horton <remy.horton@intel.com>
Tested-by: Roman Korynkevych <romanx.korynkevych@intel.com>

diff --git a/doc/guides/rel_notes/release_17_05.rst b/doc/guides/rel_notes/release_17_05.rst
index 6c202e6..fb2ee1f 100644 (file)
--- a/doc/guides/rel_notes/release_17_05.rst
+++ b/doc/guides/rel_notes/release_17_05.rst
@@ -346,6 +346,11 @@ Libraries
 Examples
 ~~~~~~~~
 
+* **l2fwd-keepalive: Fixed unclean shutdowns.**
+
+  Added clean shutdown to l2fwd-keepalive so that it can free up
+  stale resources used for inter-process communication.
+
 
 Other
 ~~~~~

diff --git a/examples/l2fwd-keepalive/main.c b/examples/l2fwd-keepalive/main.c
index 4623d2a..5fdbdef 100644 (file)
--- a/examples/l2fwd-keepalive/main.c
+++ b/examples/l2fwd-keepalive/main.c
@@ -44,6 +44,7 @@
 #include <ctype.h>
 #include <errno.h>
 #include <getopt.h>
+#include <signal.h>
 
 #include <rte_common.h>
 #include <rte_log.h>
@@ -142,6 +143,15 @@ static int64_t check_period = 5; /* default check cycle is 5ms */
 /* Keepalive structure */
 struct rte_keepalive *rte_global_keepalive_info;
 
+/* Termination signalling */
+static int terminate_signal_received;
+
+/* Termination signal handler */
+static void handle_sigterm(__rte_unused int value)
+{
+       terminate_signal_received = 1;
+}
+
 /* Print out statistics on packets dropped */
 static void
 print_stats(__attribute__((unused)) struct rte_timer *ptr_timer,
@@ -251,7 +261,7 @@ l2fwd_main_loop(void)
        uint64_t tsc_initial = rte_rdtsc();
        uint64_t tsc_lifetime = (rand()&0x07) * rte_get_tsc_hz();
 
-       while (1) {
+       while (!terminate_signal_received) {
                /* Keepalive heartbeat */
                rte_keepalive_mark_alive(rte_global_keepalive_info);
 
@@ -526,6 +536,8 @@ check_all_ports_link_status(uint8_t port_num, uint32_t port_mask)
 static void
 dead_core(__rte_unused void *ptr_data, const int id_core)
 {
+       if (terminate_signal_received)
+               return;
        printf("Dead core %i - restarting..\n", id_core);
        if (rte_eal_get_lcore_state(id_core) == FINISHED) {
                rte_eal_wait_lcore(id_core);
@@ -554,6 +566,15 @@ main(int argc, char **argv)
        uint8_t portid, last_port;
        unsigned lcore_id, rx_lcore_id;
        unsigned nb_ports_in_mask = 0;
+       struct sigaction signal_handler;
+
+       memset(&signal_handler, 0, sizeof(signal_handler));
+       terminate_signal_received = 0;
+       signal_handler.sa_handler = &handle_sigterm;
+       if (sigaction(SIGINT, &signal_handler, NULL) == -1 ||
+                       sigaction(SIGTERM, &signal_handler, NULL) == -1)
+               rte_exit(EXIT_FAILURE, "SIGNAL\n");
+
 
        /* init EAL */
        ret = rte_eal_init(argc, argv);
@@ -782,7 +803,7 @@ main(int argc, char **argv)
                                lcore_id);
                }
        }
-       for (;;) {
+       while (!terminate_signal_received) {
                rte_timer_manage();
                rte_delay_ms(5);
                }