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 #ifdef KTEST
32 #include "../kselftest.h"
33 #else
34 static inline int ksft_exit_pass(void)
35 {
36 	exit(0);
37 }
38 static inline int ksft_exit_fail(void)
39 {
40 	exit(1);
41 }
42 #endif
43 
44 #define CLOCK_REALTIME			0
45 #define CLOCK_MONOTONIC			1
46 #define CLOCK_PROCESS_CPUTIME_ID	2
47 #define CLOCK_THREAD_CPUTIME_ID		3
48 #define CLOCK_MONOTONIC_RAW		4
49 #define CLOCK_REALTIME_COARSE		5
50 #define CLOCK_MONOTONIC_COARSE		6
51 #define CLOCK_BOOTTIME			7
52 #define CLOCK_REALTIME_ALARM		8
53 #define CLOCK_BOOTTIME_ALARM		9
54 #define CLOCK_HWSPECIFIC		10
55 #define CLOCK_TAI			11
56 #define NR_CLOCKIDS			12
57 
58 
59 #define NSEC_PER_SEC 1000000000ULL
60 #define UNREASONABLE_LAT (NSEC_PER_SEC * 5) /* hopefully we resume in 5 secs */
61 
62 #define SUSPEND_SECS 15
63 int alarmcount;
64 int alarm_clock_id;
65 struct timespec start_time;
66 
67 
68 char *clockstring(int clockid)
69 {
70 	switch (clockid) {
71 	case CLOCK_REALTIME:
72 		return "CLOCK_REALTIME";
73 	case CLOCK_MONOTONIC:
74 		return "CLOCK_MONOTONIC";
75 	case CLOCK_PROCESS_CPUTIME_ID:
76 		return "CLOCK_PROCESS_CPUTIME_ID";
77 	case CLOCK_THREAD_CPUTIME_ID:
78 		return "CLOCK_THREAD_CPUTIME_ID";
79 	case CLOCK_MONOTONIC_RAW:
80 		return "CLOCK_MONOTONIC_RAW";
81 	case CLOCK_REALTIME_COARSE:
82 		return "CLOCK_REALTIME_COARSE";
83 	case CLOCK_MONOTONIC_COARSE:
84 		return "CLOCK_MONOTONIC_COARSE";
85 	case CLOCK_BOOTTIME:
86 		return "CLOCK_BOOTTIME";
87 	case CLOCK_REALTIME_ALARM:
88 		return "CLOCK_REALTIME_ALARM";
89 	case CLOCK_BOOTTIME_ALARM:
90 		return "CLOCK_BOOTTIME_ALARM";
91 	case CLOCK_TAI:
92 		return "CLOCK_TAI";
93 	};
94 	return "UNKNOWN_CLOCKID";
95 }
96 
97 
98 long long timespec_sub(struct timespec a, struct timespec b)
99 {
100 	long long ret = NSEC_PER_SEC * b.tv_sec + b.tv_nsec;
101 
102 	ret -= NSEC_PER_SEC * a.tv_sec + a.tv_nsec;
103 	return ret;
104 }
105 
106 int final_ret = 0;
107 
108 void sigalarm(int signo)
109 {
110 	long long delta_ns;
111 	struct timespec ts;
112 
113 	clock_gettime(alarm_clock_id, &ts);
114 	alarmcount++;
115 
116 	delta_ns = timespec_sub(start_time, ts);
117 	delta_ns -= NSEC_PER_SEC * SUSPEND_SECS * alarmcount;
118 
119 	printf("ALARM(%i): %ld:%ld latency: %lld ns ", alarmcount, ts.tv_sec,
120 							ts.tv_nsec, delta_ns);
121 
122 	if (delta_ns > UNREASONABLE_LAT) {
123 		printf("[FAIL]\n");
124 		final_ret = -1;
125 	} else
126 		printf("[OK]\n");
127 
128 }
129 
130 int main(void)
131 {
132 	timer_t tm1;
133 	struct itimerspec its1, its2;
134 	struct sigevent se;
135 	struct sigaction act;
136 	int signum = SIGRTMAX;
137 
138 	/* Set up signal handler: */
139 	sigfillset(&act.sa_mask);
140 	act.sa_flags = 0;
141 	act.sa_handler = sigalarm;
142 	sigaction(signum, &act, NULL);
143 
144 	/* Set up timer: */
145 	memset(&se, 0, sizeof(se));
146 	se.sigev_notify = SIGEV_SIGNAL;
147 	se.sigev_signo = signum;
148 	se.sigev_value.sival_int = 0;
149 
150 	for (alarm_clock_id = CLOCK_REALTIME_ALARM;
151 			alarm_clock_id <= CLOCK_BOOTTIME_ALARM;
152 			alarm_clock_id++) {
153 
154 		alarmcount = 0;
155 		if (timer_create(alarm_clock_id, &se, &tm1) == -1) {
156 			printf("timer_create failed, %s unsupported?\n",
157 					clockstring(alarm_clock_id));
158 			break;
159 		}
160 
161 		clock_gettime(alarm_clock_id, &start_time);
162 		printf("Start time (%s): %ld:%ld\n", clockstring(alarm_clock_id),
163 				start_time.tv_sec, start_time.tv_nsec);
164 		printf("Setting alarm for every %i seconds\n", SUSPEND_SECS);
165 		its1.it_value = start_time;
166 		its1.it_value.tv_sec += SUSPEND_SECS;
167 		its1.it_interval.tv_sec = SUSPEND_SECS;
168 		its1.it_interval.tv_nsec = 0;
169 
170 		timer_settime(tm1, TIMER_ABSTIME, &its1, &its2);
171 
172 		while (alarmcount < 5)
173 			sleep(1); /* First 5 alarms, do nothing */
174 
175 		printf("Starting suspend loops\n");
176 		while (alarmcount < 10) {
177 			int ret;
178 
179 			sleep(3);
180 			ret = system("echo mem > /sys/power/state");
181 			if (ret)
182 				break;
183 		}
184 		timer_delete(tm1);
185 	}
186 	if (final_ret)
187 		return ksft_exit_fail();
188 	return ksft_exit_pass();
189 }
190