xref: /linux/tools/testing/selftests/timers/alarmtimer-suspend.c (revision cdd30ebb1b9f36159d66f088b61aee264e649d7a)
1 /* alarmtimer suspend test
2  *		John Stultz (john.stultz@linaro.org)
3  *              (C) Copyright Linaro 2013
4  *              Licensed under the GPLv2
5  *
6  *   This test makes sure the alarmtimer & RTC wakeup code is
7  *   functioning.
8  *
9  *  To build:
10  *	$ gcc alarmtimer-suspend.c -o alarmtimer-suspend -lrt
11  *
12  *   This program is free software: you can redistribute it and/or modify
13  *   it under the terms of the GNU General Public License as published by
14  *   the Free Software Foundation, either version 2 of the License, or
15  *   (at your option) any later version.
16  *
17  *   This program is distributed in the hope that it will be useful,
18  *   but WITHOUT ANY WARRANTY; without even the implied warranty of
19  *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
20  *   GNU General Public License for more details.
21  */
22 
23 
24 #include <stdio.h>
25 #include <unistd.h>
26 #include <time.h>
27 #include <string.h>
28 #include <signal.h>
29 #include <stdlib.h>
30 #include <pthread.h>
31 #include <include/vdso/time64.h>
32 #include <errno.h>
33 #include "../kselftest.h"
34 
35 #define UNREASONABLE_LAT (NSEC_PER_SEC * 5) /* hopefully we resume in 5 secs */
36 
37 #define SUSPEND_SECS 15
38 int alarmcount;
39 int alarm_clock_id;
40 struct timespec start_time;
41 
42 
43 char *clockstring(int clockid)
44 {
45 	switch (clockid) {
46 	case CLOCK_REALTIME:
47 		return "CLOCK_REALTIME";
48 	case CLOCK_MONOTONIC:
49 		return "CLOCK_MONOTONIC";
50 	case CLOCK_PROCESS_CPUTIME_ID:
51 		return "CLOCK_PROCESS_CPUTIME_ID";
52 	case CLOCK_THREAD_CPUTIME_ID:
53 		return "CLOCK_THREAD_CPUTIME_ID";
54 	case CLOCK_MONOTONIC_RAW:
55 		return "CLOCK_MONOTONIC_RAW";
56 	case CLOCK_REALTIME_COARSE:
57 		return "CLOCK_REALTIME_COARSE";
58 	case CLOCK_MONOTONIC_COARSE:
59 		return "CLOCK_MONOTONIC_COARSE";
60 	case CLOCK_BOOTTIME:
61 		return "CLOCK_BOOTTIME";
62 	case CLOCK_REALTIME_ALARM:
63 		return "CLOCK_REALTIME_ALARM";
64 	case CLOCK_BOOTTIME_ALARM:
65 		return "CLOCK_BOOTTIME_ALARM";
66 	case CLOCK_TAI:
67 		return "CLOCK_TAI";
68 	}
69 	return "UNKNOWN_CLOCKID";
70 }
71 
72 
73 long long timespec_sub(struct timespec a, struct timespec b)
74 {
75 	long long ret = NSEC_PER_SEC * b.tv_sec + b.tv_nsec;
76 
77 	ret -= NSEC_PER_SEC * a.tv_sec + a.tv_nsec;
78 	return ret;
79 }
80 
81 int final_ret;
82 
83 void sigalarm(int signo)
84 {
85 	long long delta_ns;
86 	struct timespec ts;
87 
88 	clock_gettime(alarm_clock_id, &ts);
89 	alarmcount++;
90 
91 	delta_ns = timespec_sub(start_time, ts);
92 	delta_ns -= NSEC_PER_SEC * SUSPEND_SECS * alarmcount;
93 
94 	printf("ALARM(%i): %ld:%ld latency: %lld ns ", alarmcount, ts.tv_sec,
95 							ts.tv_nsec, delta_ns);
96 
97 	if (delta_ns > UNREASONABLE_LAT) {
98 		printf("[FAIL]\n");
99 		final_ret = -1;
100 	} else
101 		printf("[OK]\n");
102 
103 }
104 
105 int main(void)
106 {
107 	timer_t tm1;
108 	struct itimerspec its1, its2;
109 	struct sigevent se;
110 	struct sigaction act;
111 	int signum = SIGRTMAX;
112 
113 	/* Set up signal handler: */
114 	sigfillset(&act.sa_mask);
115 	act.sa_flags = 0;
116 	act.sa_handler = sigalarm;
117 	sigaction(signum, &act, NULL);
118 
119 	/* Set up timer: */
120 	memset(&se, 0, sizeof(se));
121 	se.sigev_notify = SIGEV_SIGNAL;
122 	se.sigev_signo = signum;
123 	se.sigev_value.sival_int = 0;
124 
125 	for (alarm_clock_id = CLOCK_REALTIME_ALARM;
126 			alarm_clock_id <= CLOCK_BOOTTIME_ALARM;
127 			alarm_clock_id++) {
128 
129 		alarmcount = 0;
130 		if (timer_create(alarm_clock_id, &se, &tm1) == -1) {
131 			printf("timer_create failed, %s unsupported?: %s\n",
132 					clockstring(alarm_clock_id), strerror(errno));
133 			break;
134 		}
135 
136 		clock_gettime(alarm_clock_id, &start_time);
137 		printf("Start time (%s): %ld:%ld\n", clockstring(alarm_clock_id),
138 				start_time.tv_sec, start_time.tv_nsec);
139 		printf("Setting alarm for every %i seconds\n", SUSPEND_SECS);
140 		its1.it_value = start_time;
141 		its1.it_value.tv_sec += SUSPEND_SECS;
142 		its1.it_interval.tv_sec = SUSPEND_SECS;
143 		its1.it_interval.tv_nsec = 0;
144 
145 		timer_settime(tm1, TIMER_ABSTIME, &its1, &its2);
146 
147 		while (alarmcount < 5)
148 			sleep(1); /* First 5 alarms, do nothing */
149 
150 		printf("Starting suspend loops\n");
151 		while (alarmcount < 10) {
152 			int ret;
153 
154 			sleep(3);
155 			ret = system("echo mem > /sys/power/state");
156 			if (ret)
157 				break;
158 		}
159 		timer_delete(tm1);
160 	}
161 	if (final_ret)
162 		ksft_exit_fail();
163 	ksft_exit_pass();
164 }
165