selftests/timers: Add alarmtimer-suspend test from timetests suite

This adds the alarmtimer-suspend test from the timetests suite,
which tests that the alarmtimers wake the system up from suspend
shortly after the time they were set to fire.

Cc: Shuah Khan <shuahkh@osg.samsung.com>
Cc: Prarit Bhargava <prarit@redhat.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Richard Cochran <richardcochran@gmail.com>
Signed-off-by: John Stultz <john.stultz@linaro.org>
Tested-by: Prarit Bhargava <prarit@redhat.com>
Signed-off-by: Shuah Khan <shuahkh@osg.samsung.com>

tools/testing/selftests/timers/Makefile

@@ -3,7 +3,8 @@ BUILD_FLAGS = -DKTEST
 CFLAGS += -O3 -Wl,-no-as-needed -Wall $(BUILD_FLAGS)
 LDFLAGS += -lrt -lpthread
 bins = posix_timers nanosleep inconsistency-check nsleep-lat raw_skew \
-	set-timer-lat threadtest mqueue-lat valid-adjtimex
+	set-timer-lat threadtest mqueue-lat valid-adjtimex \
+	alarmtimer-suspend
 
 all: ${bins}
 
@@ -22,7 +23,8 @@ run_tests: all
 # these tests require escalated privledges
 # and may modify the system time or trigger
 # other behavior like suspend
-run_destructive_tests: all
+run_destructive_tests: run_tests
+	./alarmtimer-suspend
 	./valid-adjtimex
 
 clean:

tools/testing/selftests/timers/alarmtimer-suspend.c

+/* alarmtimer suspend test
+ *		John Stultz (john.stultz@linaro.org)
+ *              (C) Copyright Linaro 2013
+ *              Licensed under the GPLv2
+ *
+ *   This test makes sure the alarmtimer & RTC wakeup code is
+ *   functioning.
+ *
+ *  To build:
+ *	$ gcc alarmtimer-suspend.c -o alarmtimer-suspend -lrt
+ *
+ *   This program is free software: you can redistribute it and/or modify
+ *   it under the terms of the GNU General Public License as published by
+ *   the Free Software Foundation, either version 2 of the License, or
+ *   (at your option) any later version.
+ *
+ *   This program is distributed in the hope that it will be useful,
+ *   but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *   GNU General Public License for more details.
+ */
+
+
+#include <stdio.h>
+#include <unistd.h>
+#include <time.h>
+#include <string.h>
+#include <signal.h>
+#include <stdlib.h>
+#include <pthread.h>
+#ifdef KTEST
+#include "../kselftest.h"
+#else
+static inline int ksft_exit_pass(void)
+{
+	exit(0);
+}
+static inline int ksft_exit_fail(void)
+{
+	exit(1);
+}
+#endif
+
+#define CLOCK_REALTIME			0
+#define CLOCK_MONOTONIC			1
+#define CLOCK_PROCESS_CPUTIME_ID	2
+#define CLOCK_THREAD_CPUTIME_ID		3
+#define CLOCK_MONOTONIC_RAW		4
+#define CLOCK_REALTIME_COARSE		5
+#define CLOCK_MONOTONIC_COARSE		6
+#define CLOCK_BOOTTIME			7
+#define CLOCK_REALTIME_ALARM		8
+#define CLOCK_BOOTTIME_ALARM		9
+#define CLOCK_HWSPECIFIC		10
+#define CLOCK_TAI			11
+#define NR_CLOCKIDS			12
+
+
+#define NSEC_PER_SEC 1000000000ULL
+#define UNREASONABLE_LAT (NSEC_PER_SEC * 4) /* hopefully we resume in 4secs */
+
+#define SUSPEND_SECS 15
+int alarmcount;
+int alarm_clock_id;
+struct timespec start_time;
+
+
+char *clockstring(int clockid)
+{
+	switch (clockid) {
+	case CLOCK_REALTIME:
+		return "CLOCK_REALTIME";
+	case CLOCK_MONOTONIC:
+		return "CLOCK_MONOTONIC";
+	case CLOCK_PROCESS_CPUTIME_ID:
+		return "CLOCK_PROCESS_CPUTIME_ID";
+	case CLOCK_THREAD_CPUTIME_ID:
+		return "CLOCK_THREAD_CPUTIME_ID";
+	case CLOCK_MONOTONIC_RAW:
+		return "CLOCK_MONOTONIC_RAW";
+	case CLOCK_REALTIME_COARSE:
+		return "CLOCK_REALTIME_COARSE";
+	case CLOCK_MONOTONIC_COARSE:
+		return "CLOCK_MONOTONIC_COARSE";
+	case CLOCK_BOOTTIME:
+		return "CLOCK_BOOTTIME";
+	case CLOCK_REALTIME_ALARM:
+		return "CLOCK_REALTIME_ALARM";
+	case CLOCK_BOOTTIME_ALARM:
+		return "CLOCK_BOOTTIME_ALARM";
+	case CLOCK_TAI:
+		return "CLOCK_TAI";
+	};
+	return "UNKNOWN_CLOCKID";
+}
+
+
+long long timespec_sub(struct timespec a, struct timespec b)
+{
+	long long ret = NSEC_PER_SEC * b.tv_sec + b.tv_nsec;
+
+	ret -= NSEC_PER_SEC * a.tv_sec + a.tv_nsec;
+	return ret;
+}
+
+int final_ret = 0;
+
+void sigalarm(int signo)
+{
+	long long delta_ns;
+	struct timespec ts;
+
+	clock_gettime(alarm_clock_id, &ts);
+	alarmcount++;
+
+	delta_ns = timespec_sub(start_time, ts);
+	delta_ns -= NSEC_PER_SEC * SUSPEND_SECS * alarmcount;
+
+	printf("ALARM(%i): %ld:%ld latency: %lld ns ", alarmcount, ts.tv_sec,
+							ts.tv_nsec, delta_ns);
+
+	if (delta_ns > UNREASONABLE_LAT) {
+		printf("[FAIL]\n");
+		final_ret = -1;
+	} else
+		printf("[OK]\n");
+
+}
+
+int main(void)
+{
+	timer_t tm1;
+	struct itimerspec its1, its2;
+	struct sigevent se;
+	struct sigaction act;
+	int signum = SIGRTMAX;
+
+	/* Set up signal handler: */
+	sigfillset(&act.sa_mask);
+	act.sa_flags = 0;
+	act.sa_handler = sigalarm;
+	sigaction(signum, &act, NULL);
+
+	/* Set up timer: */
+	memset(&se, 0, sizeof(se));
+	se.sigev_notify = SIGEV_SIGNAL;
+	se.sigev_signo = signum;
+	se.sigev_value.sival_int = 0;
+
+	for (alarm_clock_id = CLOCK_REALTIME_ALARM;
+			alarm_clock_id <= CLOCK_BOOTTIME_ALARM;
+			alarm_clock_id++) {
+
+		alarmcount = 0;
+		timer_create(alarm_clock_id, &se, &tm1);
+
+		clock_gettime(alarm_clock_id, &start_time);
+		printf("Start time (%s): %ld:%ld\n", clockstring(alarm_clock_id),
+				start_time.tv_sec, start_time.tv_nsec);
+		printf("Setting alarm for every %i seconds\n", SUSPEND_SECS);
+		its1.it_value = start_time;
+		its1.it_value.tv_sec += SUSPEND_SECS;
+		its1.it_interval.tv_sec = SUSPEND_SECS;
+		its1.it_interval.tv_nsec = 0;
+
+		timer_settime(tm1, TIMER_ABSTIME, &its1, &its2);
+
+		while (alarmcount < 5)
+			sleep(1); /* First 5 alarms, do nothing */
+
+		printf("Starting suspend loops\n");
+		while (alarmcount < 10) {
+			int ret;
+
+			sleep(1);
+			ret = system("echo mem > /sys/power/state");
+			if (ret)
+				break;
+		}
+		timer_delete(tm1);
+	}
+	if (final_ret)
+		return ksft_exit_fail();
+	return ksft_exit_pass();
+}