watchfrr: Send operational state to systemd

When watchfrr has noticed issues, send operational state
to systemd so operators issuing `systemd status frr` can
see a more nuanced state of the daemon.

Add the `--operational-timeout X` value to the cli. After
the daemon has been restarted and communication re-established
wait this time before reporting to systemd that the daemon
is up and running.

Default value of 60 seconds was choosen to allow some small
delay in reporting so that, if the daemon is in a crash loop
status will not ping pong.

Signed-off-by: Donald Sharp <sharpd@nvidia.com>

1 files changed, 42 insertions, 7 deletions

diff --git a/watchfrr/watchfrr.c b/watchfrr/watchfrr.c
index 3a5919ede..e5afa6898 100644
--- a/watchfrr/watchfrr.c
+++ b/watchfrr/watchfrr.c
@@ -54,6 +54,7 @@
 #define DEFAULT_LOGLEVEL	LOG_INFO
 #define DEFAULT_MIN_RESTART	60
 #define DEFAULT_MAX_RESTART	600
+#define DEFAULT_OPERATIONAL_TIMEOUT 60
 
 #define DEFAULT_RESTART_CMD	WATCHFRR_SH_PATH " restart %s"
 #define DEFAULT_START_CMD	WATCHFRR_SH_PATH " start %s"
@@ -106,12 +107,14 @@ static struct global_state {
 	enum restart_phase phase;
 	struct thread *t_phase_hanging;
 	struct thread *t_startup_timeout;
+	struct thread *t_operational;
 	const char *vtydir;
 	long period;
 	long timeout;
 	long restart_timeout;
 	long min_restart_interval;
 	long max_restart_interval;
+	long operational_timeout;
 	struct daemon *daemons;
 	const char *restart_command;
 	const char *start_command;
@@ -131,6 +134,7 @@ static struct global_state {
 	.loglevel = DEFAULT_LOGLEVEL,
 	.min_restart_interval = DEFAULT_MIN_RESTART,
 	.max_restart_interval = DEFAULT_MAX_RESTART,
+	.operational_timeout = DEFAULT_OPERATIONAL_TIMEOUT,
 	.restart_command = DEFAULT_RESTART_CMD,
 	.start_command = DEFAULT_START_CMD,
 	.stop_command = DEFAULT_STOP_CMD,
@@ -177,6 +181,7 @@ struct daemon {
 #define OPTION_MAXRESTART 2001
 #define OPTION_DRY        2002
 #define OPTION_NETNS      2003
+#define OPTION_MAXOPERATIONAL 2004
 
 static const struct option longopts[] = {
 	{"daemon", no_argument, NULL, 'd'},
@@ -191,6 +196,7 @@ static const struct option longopts[] = {
 	{"dry", no_argument, NULL, OPTION_DRY},
 	{"min-restart-interval", required_argument, NULL, OPTION_MINRESTART},
 	{"max-restart-interval", required_argument, NULL, OPTION_MAXRESTART},
+	{"operational-timeout", required_argument, NULL, OPTION_MAXOPERATIONAL},
 	{"pid-file", required_argument, NULL, 'p'},
 	{"blank-string", required_argument, NULL, 'b'},
 #ifdef GNU_LINUX
@@ -265,6 +271,9 @@ Otherwise, the interval is doubled (but capped at the -M value).\n\n",
     --max-restart-interval\n\
 		Set the maximum seconds to wait between invocations of daemon\n\
 		restart commands (default is %d).\n\
+    --operational-timeout\n\
+                Set the time before systemd is notified that we are considered\n\
+                operational again after a daemon restart (default is %d).\n\
 -i, --interval	Set the status polling interval in seconds (default is %d)\n\
 -t, --timeout	Set the unresponsiveness timeout in seconds (default is %d)\n\
 -T, --restart-timeout\n\
@@ -296,10 +305,10 @@ Otherwise, the interval is doubled (but capped at the -M value).\n\n",
 -v, --version	Print program version\n\
 -h, --help	Display this help and exit\n",
 		frr_vtydir, DEFAULT_LOGLEVEL, LOG_EMERG, LOG_DEBUG, LOG_DEBUG,
-		DEFAULT_MIN_RESTART, DEFAULT_MAX_RESTART, DEFAULT_PERIOD,
-		DEFAULT_TIMEOUT, DEFAULT_RESTART_TIMEOUT,
-		DEFAULT_RESTART_CMD, DEFAULT_START_CMD, DEFAULT_STOP_CMD,
-		frr_vtydir);
+		DEFAULT_MIN_RESTART, DEFAULT_MAX_RESTART,
+		DEFAULT_OPERATIONAL_TIMEOUT, DEFAULT_PERIOD, DEFAULT_TIMEOUT,
+		DEFAULT_RESTART_TIMEOUT, DEFAULT_RESTART_CMD, DEFAULT_START_CMD,
+		DEFAULT_STOP_CMD, frr_vtydir);
 }
 
 static pid_t run_background(char *shell_cmd)
@@ -502,8 +511,6 @@ static int run_job(struct restart_info *restart, const char *cmdtype,
 			restart->pid = 0;
 	}
 
-	systemd_send_status("FRR Operational");
-
 	/* Calculate the new restart interval. */
 	if (update_interval) {
 		if (delay.tv_sec > 2 * gs.max_restart_interval)
@@ -584,6 +591,11 @@ static void restart_done(struct daemon *dmn)
 		SET_WAKEUP_DOWN(dmn);
 }
 
+static void daemon_restarting_operational(struct thread *thread)
+{
+	systemd_send_status("FRR Operational");
+}
+
 static void daemon_down(struct daemon *dmn, const char *why)
 {
 	if (IS_UP(dmn) || (dmn->state == DAEMON_INIT))
@@ -603,6 +615,8 @@ static void daemon_down(struct daemon *dmn, const char *why)
 	THREAD_OFF(dmn->t_wakeup);
 	if (try_connect(dmn) < 0)
 		SET_WAKEUP_DOWN(dmn);
+
+	systemd_send_status("FRR partially operational");
 	phase_check();
 }
 
@@ -721,8 +735,15 @@ static void daemon_up(struct daemon *dmn, const char *why)
 	gs.numdown--;
 	dmn->connect_tries = 0;
 	zlog_notice("%s state -> up : %s", dmn->name, why);
-	if (gs.numdown == 0)
+	if (gs.numdown == 0) {
 		daemon_send_ready(0);
+
+		THREAD_OFF(gs.t_operational);
+
+		thread_add_timer(master, daemon_restarting_operational, NULL,
+				 gs.operational_timeout, &gs.t_operational);
+	}
+
 	SET_WAKEUP_ECHO(dmn);
 	phase_check();
 }
@@ -889,6 +910,7 @@ static void phase_check(void)
 	case PHASE_WAITING_DOWN:
 		if (gs.numdown + IS_UP(gs.special) < gs.numdaemons)
 			break;
+		systemd_send_status("Phased Restart");
 		zlog_info("Phased restart: all routing daemons now down.");
 		run_job(&gs.special->restart, "restart", gs.restart_command, 1,
 			1);
@@ -898,6 +920,7 @@ static void phase_check(void)
 	case PHASE_ZEBRA_RESTART_PENDING:
 		if (gs.special->restart.pid)
 			break;
+		systemd_send_status("Zebra Restarting");
 		zlog_info("Phased restart: %s restart job completed.",
 			  gs.special->name);
 		set_phase(PHASE_WAITING_ZEBRA_UP);
@@ -1395,6 +1418,18 @@ int main(int argc, char **argv)
 				frr_help_exit(1);
 			}
 		} break;
+		case OPTION_MAXOPERATIONAL: {
+			char garbage[3];
+
+			if ((sscanf(optarg, "%ld%1s", &gs.operational_timeout,
+				    garbage) != 1) ||
+			    (gs.max_restart_interval < 0)) {
+				fprintf(stderr,
+					"Invalid Operational_timeout argument: %s\n",
+					optarg);
+				frr_help_exit(1);
+			}
+		} break;
 		case OPTION_NETNS:
 			netns_en = true;
 			if (optarg && strchr(optarg, '/')) {