1 // SPDX-License-Identifier: GPL-2.0
2 /*
3 * Copyright (C) 2015 Anton Ivanov (aivanov@{brocade.com,kot-begemot.co.uk})
4 * Copyright (C) 2015 Thomas Meyer (thomas@m3y3r.de)
5 * Copyright (C) 2012-2014 Cisco Systems
6 * Copyright (C) 2000 - 2007 Jeff Dike (jdike{addtoit,linux.intel}.com)
7 */
8
9 #include <stddef.h>
10 #include <unistd.h>
11 #include <errno.h>
12 #include <signal.h>
13 #include <time.h>
14 #include <sys/time.h>
15 #include <kern_util.h>
16 #include <os.h>
17 #include <string.h>
18
19 static timer_t event_high_res_timer = 0;
20
timeval_to_ns(const struct timeval * tv)21 static inline long long timeval_to_ns(const struct timeval *tv)
22 {
23 return ((long long) tv->tv_sec * UM_NSEC_PER_SEC) +
24 tv->tv_usec * UM_NSEC_PER_USEC;
25 }
26
timespec_to_ns(const struct timespec * ts)27 static inline long long timespec_to_ns(const struct timespec *ts)
28 {
29 return ((long long) ts->tv_sec * UM_NSEC_PER_SEC) + ts->tv_nsec;
30 }
31
os_persistent_clock_emulation(void)32 long long os_persistent_clock_emulation(void)
33 {
34 struct timespec realtime_tp;
35
36 clock_gettime(CLOCK_REALTIME, &realtime_tp);
37 return timespec_to_ns(&realtime_tp);
38 }
39
40 /**
41 * os_timer_create() - create an new posix (interval) timer
42 */
os_timer_create(void)43 int os_timer_create(void)
44 {
45 timer_t *t = &event_high_res_timer;
46
47 if (timer_create(CLOCK_MONOTONIC, NULL, t) == -1)
48 return -1;
49
50 return 0;
51 }
52
os_timer_set_interval(unsigned long long nsecs)53 int os_timer_set_interval(unsigned long long nsecs)
54 {
55 struct itimerspec its;
56
57 its.it_value.tv_sec = nsecs / UM_NSEC_PER_SEC;
58 its.it_value.tv_nsec = nsecs % UM_NSEC_PER_SEC;
59
60 its.it_interval.tv_sec = nsecs / UM_NSEC_PER_SEC;
61 its.it_interval.tv_nsec = nsecs % UM_NSEC_PER_SEC;
62
63 if (timer_settime(event_high_res_timer, 0, &its, NULL) == -1)
64 return -errno;
65
66 return 0;
67 }
68
os_timer_one_shot(unsigned long long nsecs)69 int os_timer_one_shot(unsigned long long nsecs)
70 {
71 struct itimerspec its = {
72 .it_value.tv_sec = nsecs / UM_NSEC_PER_SEC,
73 .it_value.tv_nsec = nsecs % UM_NSEC_PER_SEC,
74
75 .it_interval.tv_sec = 0,
76 .it_interval.tv_nsec = 0, // we cheat here
77 };
78
79 timer_settime(event_high_res_timer, 0, &its, NULL);
80 return 0;
81 }
82
83 /**
84 * os_timer_disable() - disable the posix (interval) timer
85 */
os_timer_disable(void)86 void os_timer_disable(void)
87 {
88 struct itimerspec its;
89
90 memset(&its, 0, sizeof(struct itimerspec));
91 timer_settime(event_high_res_timer, 0, &its, NULL);
92 }
93
os_nsecs(void)94 long long os_nsecs(void)
95 {
96 struct timespec ts;
97
98 clock_gettime(CLOCK_MONOTONIC,&ts);
99 return timespec_to_ns(&ts);
100 }
101
102 /**
103 * os_idle_sleep() - sleep until interrupted
104 */
os_idle_sleep(void)105 void os_idle_sleep(void)
106 {
107 struct itimerspec its;
108 sigset_t set, old;
109
110 /* block SIGALRM while we analyze the timer state */
111 sigemptyset(&set);
112 sigaddset(&set, SIGALRM);
113 sigprocmask(SIG_BLOCK, &set, &old);
114
115 /* check the timer, and if it'll fire then wait for it */
116 timer_gettime(event_high_res_timer, &its);
117 if (its.it_value.tv_sec || its.it_value.tv_nsec)
118 sigsuspend(&old);
119 /* either way, restore the signal mask */
120 sigprocmask(SIG_UNBLOCK, &set, NULL);
121 }
122