1/* Make sure timers don't return early
  2 *              by: john stultz (johnstul@us.ibm.com)
  3 *		    John Stultz (john.stultz@linaro.org)
  4 *              (C) Copyright IBM 2012
  5 *              (C) Copyright Linaro 2013 2015
  6 *              Licensed under the GPLv2
  7 *
  8 *  To build:
  9 *	$ gcc nanosleep.c -o nanosleep -lrt
 10 *
 11 *   This program is free software: you can redistribute it and/or modify
 12 *   it under the terms of the GNU General Public License as published by
 13 *   the Free Software Foundation, either version 2 of the License, or
 14 *   (at your option) any later version.
 15 *
 16 *   This program is distributed in the hope that it will be useful,
 17 *   but WITHOUT ANY WARRANTY; without even the implied warranty of
 18 *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 19 *   GNU General Public License for more details.
 20 */
 21
 22#include <errno.h>
 23#include <stdio.h>
 24#include <stdlib.h>
 25#include <time.h>
 26#include <sys/time.h>
 27#include <sys/timex.h>
 28#include <string.h>
 29#include <signal.h>
 30#include "../kselftest.h"
 31
 32#define NSEC_PER_SEC 1000000000ULL
 33
 34#define CLOCK_REALTIME			0
 35#define CLOCK_MONOTONIC			1
 36#define CLOCK_PROCESS_CPUTIME_ID	2
 37#define CLOCK_THREAD_CPUTIME_ID		3
 38#define CLOCK_MONOTONIC_RAW		4
 39#define CLOCK_REALTIME_COARSE		5
 40#define CLOCK_MONOTONIC_COARSE		6
 41#define CLOCK_BOOTTIME			7
 42#define CLOCK_REALTIME_ALARM		8
 43#define CLOCK_BOOTTIME_ALARM		9
 44#define CLOCK_HWSPECIFIC		10
 45#define CLOCK_TAI			11
 46#define NR_CLOCKIDS			12
 47
 48#define UNSUPPORTED 0xf00f
 49
 50char *clockstring(int clockid)
 51{
 52	switch (clockid) {
 53	case CLOCK_REALTIME:
 54		return "CLOCK_REALTIME";
 55	case CLOCK_MONOTONIC:
 56		return "CLOCK_MONOTONIC";
 57	case CLOCK_PROCESS_CPUTIME_ID:
 58		return "CLOCK_PROCESS_CPUTIME_ID";
 59	case CLOCK_THREAD_CPUTIME_ID:
 60		return "CLOCK_THREAD_CPUTIME_ID";
 61	case CLOCK_MONOTONIC_RAW:
 62		return "CLOCK_MONOTONIC_RAW";
 63	case CLOCK_REALTIME_COARSE:
 64		return "CLOCK_REALTIME_COARSE";
 65	case CLOCK_MONOTONIC_COARSE:
 66		return "CLOCK_MONOTONIC_COARSE";
 67	case CLOCK_BOOTTIME:
 68		return "CLOCK_BOOTTIME";
 69	case CLOCK_REALTIME_ALARM:
 70		return "CLOCK_REALTIME_ALARM";
 71	case CLOCK_BOOTTIME_ALARM:
 72		return "CLOCK_BOOTTIME_ALARM";
 73	case CLOCK_TAI:
 74		return "CLOCK_TAI";
 75	};
 76	return "UNKNOWN_CLOCKID";
 77}
 78
 79/* returns 1 if a <= b, 0 otherwise */
 80static inline int in_order(struct timespec a, struct timespec b)
 81{
 82	if (a.tv_sec < b.tv_sec)
 83		return 1;
 84	if (a.tv_sec > b.tv_sec)
 85		return 0;
 86	if (a.tv_nsec > b.tv_nsec)
 87		return 0;
 88	return 1;
 89}
 90
 91struct timespec timespec_add(struct timespec ts, unsigned long long ns)
 92{
 93	ts.tv_nsec += ns;
 94	while (ts.tv_nsec >= NSEC_PER_SEC) {
 95		ts.tv_nsec -= NSEC_PER_SEC;
 96		ts.tv_sec++;
 97	}
 98	return ts;
 99}
100
101int nanosleep_test(int clockid, long long ns)
102{
103	struct timespec now, target, rel;
104
105	/* First check abs time */
106	if (clock_gettime(clockid, &now))
107		return UNSUPPORTED;
108	target = timespec_add(now, ns);
109
110	if (clock_nanosleep(clockid, TIMER_ABSTIME, &target, NULL))
111		return UNSUPPORTED;
112	clock_gettime(clockid, &now);
113
114	if (!in_order(target, now))
115		return -1;
116
117	/* Second check reltime */
118	clock_gettime(clockid, &now);
119	rel.tv_sec = 0;
120	rel.tv_nsec = 0;
121	rel = timespec_add(rel, ns);
122	target = timespec_add(now, ns);
123	clock_nanosleep(clockid, 0, &rel, NULL);
124	clock_gettime(clockid, &now);
125
126	if (!in_order(target, now))
127		return -1;
128	return 0;
129}
130
131int main(int argc, char **argv)
132{
133	long long length;
134	int clockid, ret;
135
136	ksft_print_header();
137	ksft_set_plan(NR_CLOCKIDS);
138
139	for (clockid = CLOCK_REALTIME; clockid < NR_CLOCKIDS; clockid++) {
140
141		/* Skip cputime clockids since nanosleep won't increment cputime */
142		if (clockid == CLOCK_PROCESS_CPUTIME_ID ||
143				clockid == CLOCK_THREAD_CPUTIME_ID ||
144				clockid == CLOCK_HWSPECIFIC) {
145			ksft_test_result_skip("%-31s\n", clockstring(clockid));
146			continue;
147		}
148
149		fflush(stdout);
150
151		length = 10;
152		while (length <= (NSEC_PER_SEC * 10)) {
153			ret = nanosleep_test(clockid, length);
154			if (ret == UNSUPPORTED) {
155				ksft_test_result_skip("%-31s\n", clockstring(clockid));
156				goto next;
157			}
158			if (ret < 0) {
159				ksft_test_result_fail("%-31s\n", clockstring(clockid));
160				ksft_exit_fail();
161			}
162			length *= 100;
163		}
164		ksft_test_result_pass("%-31s\n", clockstring(clockid));
165next:
166		ret = 0;
167	}
168	ksft_exit_pass();
169}