test/zdtm: add a new test to check non-periodic timers

It creates a few timers with log expiration intervals, waites for C/R
and check that timers are armed and their intervals have been restored.

Signed-off-by: Austin Kuo <hsuanchikuo@gmail.com>

test/zdtm/static/Makefile

@@ -24,6 +24,7 @@ TST_NOFILE	:=				\
 		sse20				\
 		mprotect00			\
 		timers				\
+		timers01			\
 		timerfd				\
 		unbound_sock			\
 		sched_prio00			\

test/zdtm/static/timers01.c

@@ -0,0 +1,74 @@
+#include <stdlib.h>
+#include <signal.h>
+#include <sys/time.h>
+
+#include "zdtmtst.h"
+
+const char *test_doc = "Checks non-periodic timers\n";
+const char *test_author = "Andrei Vagin <avagin@gmail.com>";
+
+static struct {
+	const int timer_type;
+	const int signal;
+	volatile sig_atomic_t count;
+} timer_tests[] = {
+	/* from slowest to fastest */
+	{ ITIMER_VIRTUAL, SIGVTALRM },
+	{ ITIMER_PROF, SIGPROF },
+	{ ITIMER_REAL, SIGALRM },
+};
+
+#define NUM_TIMERS (sizeof(timer_tests) / sizeof(timer_tests[0]))
+#define TIMER_TIMEOUT 3600
+#define TIMER_ALLOWED_DELTA 300
+
+static void setup_timers(void)
+{
+	int i;
+	struct itimerval tv = {
+		.it_interval = { .tv_sec = 0, .tv_usec = 0 },
+		.it_value = { .tv_sec = TIMER_TIMEOUT, .tv_usec = 0 },
+	};
+
+	for (i = 0; i < NUM_TIMERS; i++) {
+		if (setitimer(timer_tests[i].timer_type, &tv, NULL) < 0) {
+			pr_perror("can't set timer %d", i);
+			exit(1);
+		}
+	}
+}
+
+static void check_timers(void)
+{
+	int i;
+
+	for (i = 0; i < NUM_TIMERS; i++) {
+		struct itimerval tv = {};
+
+		if (getitimer(timer_tests[i].timer_type, &tv)) {
+			pr_perror("gettimer");
+			exit(1);
+		}
+		if (tv.it_value.tv_sec > TIMER_TIMEOUT ||
+		    tv.it_value.tv_sec < TIMER_TIMEOUT - TIMER_ALLOWED_DELTA) {
+			fail("%ld isn't in [%d, %d]", (long)tv.it_value.tv_sec,
+					TIMER_TIMEOUT,
+					TIMER_TIMEOUT - TIMER_ALLOWED_DELTA);
+			exit(1);
+		}
+	}
+	pass();
+}
+
+int main(int argc, char **argv)
+{
+	test_init(argc, argv);
+
+	setup_timers();
+
+	test_daemon();
+	test_waitsig();
+
+	check_timers();
+	return 0;
+}