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
21 static inline long long timespec_to_ns(const struct timespec *ts)
22 {
23 return ((long long) ts->tv_sec * UM_NSEC_PER_SEC) + ts->tv_nsec;
24 }
25
26 long long os_persistent_clock_emulation(void)
27 {
28 struct timespec realtime_tp;
29
30 clock_gettime(CLOCK_REALTIME, &realtime_tp);
31 return timespec_to_ns(&realtime_tp);
32 }
33
34 /**
35 * os_timer_create() - create an new posix (interval) timer
36 */
37 int os_timer_create(void)
38 {
39 timer_t *t = &event_high_res_timer;
40
41 if (timer_create(CLOCK_MONOTONIC, NULL, t) == -1)
42 return -1;
43
44 return 0;
45 }
46
47 int os_timer_set_interval(unsigned long long nsecs)
48 {
49 struct itimerspec its;
50
51 its.it_value.tv_sec = nsecs / UM_NSEC_PER_SEC;
52 its.it_value.tv_nsec = nsecs % UM_NSEC_PER_SEC;
53
54 its.it_interval.tv_sec = nsecs / UM_NSEC_PER_SEC;
55 its.it_interval.tv_nsec = nsecs % UM_NSEC_PER_SEC;
56
57 if (timer_settime(event_high_res_timer, 0, &its, NULL) == -1)
58 return -errno;
59
60 return 0;
61 }
62
63 int os_timer_one_shot(unsigned long long nsecs)
64 {
65 struct itimerspec its = {
66 .it_value.tv_sec = nsecs / UM_NSEC_PER_SEC,
67 .it_value.tv_nsec = nsecs % UM_NSEC_PER_SEC,
68
69 .it_interval.tv_sec = 0,
70 .it_interval.tv_nsec = 0, // we cheat here
71 };
72
73 timer_settime(event_high_res_timer, 0, &its, NULL);
74 return 0;
75 }
76
77 /**
78 * os_timer_disable() - disable the posix (interval) timer
79 */
80 void os_timer_disable(void)
81 {
82 struct itimerspec its;
83
84 memset(&its, 0, sizeof(struct itimerspec));
85 timer_settime(event_high_res_timer, 0, &its, NULL);
86 }
87
88 long long os_nsecs(void)
89 {
90 struct timespec ts;
91
92 clock_gettime(CLOCK_MONOTONIC,&ts);
93 return timespec_to_ns(&ts);
94 }
95
96 /**
97 * os_idle_sleep() - sleep until interrupted
98 */
99 void os_idle_sleep(void)
100 {
101 struct itimerspec its;
102 sigset_t set, old;
103
104 /* block SIGALRM while we analyze the timer state */
105 sigemptyset(&set);
106 sigaddset(&set, SIGALRM);
107 sigprocmask(SIG_BLOCK, &set, &old);
108
109 /* check the timer, and if it'll fire then wait for it */
110 timer_gettime(event_high_res_timer, &its);
111 if (its.it_value.tv_sec || its.it_value.tv_nsec)
112 sigsuspend(&old);
113 /* either way, restore the signal mask */
114 sigprocmask(SIG_UNBLOCK, &set, NULL);
115 }
116
Linux® is a registered trademark of Linus Torvalds in the United States and other countries.
TOMOYO® is a registered trademark of NTT DATA CORPORATION.