1 /*
2 * Copyright (C) 2015 Anton Ivanov (aivanov@{brocade.com,kot-begemot.co.uk})
3 * Copyright (C) 2015 Thomas Meyer (thomas@m3y3r.de)
4 * Copyright (C) 2012-2014 Cisco Systems
5 * Copyright (C) 2000 - 2007 Jeff Dike (jdike{addtoit,linux.intel}.com)
6 * Licensed under the GPL
7 */
8
9 #include <stddef.h>
10 #include <errno.h>
11 #include <signal.h>
12 #include <time.h>
13 #include <sys/time.h>
14 #include <kern_util.h>
15 #include <os.h>
16 #include <string.h>
17 #include <timer-internal.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) +
30 ts->tv_nsec;
31 }
32
os_persistent_clock_emulation(void)33 long long os_persistent_clock_emulation (void) {
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 * timer)43 int os_timer_create(void* timer) {
44
45 timer_t* t = timer;
46
47 if(t == NULL) {
48 t = &event_high_res_timer;
49 }
50
51 if (timer_create(
52 CLOCK_MONOTONIC,
53 NULL,
54 t) == -1) {
55 return -1;
56 }
57 return 0;
58 }
59
os_timer_set_interval(void * timer,void * i)60 int os_timer_set_interval(void* timer, void* i)
61 {
62 struct itimerspec its;
63 unsigned long long nsec;
64 timer_t* t = timer;
65 struct itimerspec* its_in = i;
66
67 if(t == NULL) {
68 t = &event_high_res_timer;
69 }
70
71 nsec = UM_NSEC_PER_SEC / UM_HZ;
72
73 if(its_in != NULL) {
74 its.it_value.tv_sec = its_in->it_value.tv_sec;
75 its.it_value.tv_nsec = its_in->it_value.tv_nsec;
76 } else {
77 its.it_value.tv_sec = 0;
78 its.it_value.tv_nsec = nsec;
79 }
80
81 its.it_interval.tv_sec = 0;
82 its.it_interval.tv_nsec = nsec;
83
84 if(timer_settime(*t, 0, &its, NULL) == -1) {
85 return -errno;
86 }
87
88 return 0;
89 }
90
91 /**
92 * os_timer_remain() - returns the remaining nano seconds of the given interval
93 * timer
94 * Because this is the remaining time of an interval timer, which correspondends
95 * to HZ, this value can never be bigger than one second. Just
96 * the nanosecond part of the timer is returned.
97 * The returned time is relative to the start time of the interval timer.
98 * Return an negative value in an error case.
99 */
os_timer_remain(void * timer)100 long os_timer_remain(void* timer)
101 {
102 struct itimerspec its;
103 timer_t* t = timer;
104
105 if(t == NULL) {
106 t = &event_high_res_timer;
107 }
108
109 if(timer_gettime(t, &its) == -1) {
110 return -errno;
111 }
112
113 return its.it_value.tv_nsec;
114 }
115
os_timer_one_shot(int ticks)116 int os_timer_one_shot(int ticks)
117 {
118 struct itimerspec its;
119 unsigned long long nsec;
120 unsigned long sec;
121
122 nsec = (ticks + 1);
123 sec = nsec / UM_NSEC_PER_SEC;
124 nsec = nsec % UM_NSEC_PER_SEC;
125
126 its.it_value.tv_sec = nsec / UM_NSEC_PER_SEC;
127 its.it_value.tv_nsec = nsec;
128
129 its.it_interval.tv_sec = 0;
130 its.it_interval.tv_nsec = 0; // we cheat here
131
132 timer_settime(event_high_res_timer, 0, &its, NULL);
133 return 0;
134 }
135
136 /**
137 * os_timer_disable() - disable the posix (interval) timer
138 * Returns the remaining interval timer time in nanoseconds
139 */
os_timer_disable(void)140 long long os_timer_disable(void)
141 {
142 struct itimerspec its;
143
144 memset(&its, 0, sizeof(struct itimerspec));
145 timer_settime(event_high_res_timer, 0, &its, &its);
146
147 return its.it_value.tv_sec * UM_NSEC_PER_SEC + its.it_value.tv_nsec;
148 }
149
os_vnsecs(void)150 long long os_vnsecs(void)
151 {
152 struct timespec ts;
153
154 clock_gettime(CLOCK_PROCESS_CPUTIME_ID,&ts);
155 return timespec_to_ns(&ts);
156 }
157
os_nsecs(void)158 long long os_nsecs(void)
159 {
160 struct timespec ts;
161
162 clock_gettime(CLOCK_MONOTONIC,&ts);
163 return timespec_to_ns(&ts);
164 }
165
166 /**
167 * os_idle_sleep() - sleep for a given time of nsecs
168 * @nsecs: nanoseconds to sleep
169 */
os_idle_sleep(unsigned long long nsecs)170 void os_idle_sleep(unsigned long long nsecs)
171 {
172 struct timespec ts;
173
174 if (nsecs <= 0) {
175 return;
176 }
177
178 ts = ((struct timespec) {
179 .tv_sec = nsecs / UM_NSEC_PER_SEC,
180 .tv_nsec = nsecs % UM_NSEC_PER_SEC
181 });
182
183 /*
184 * Relay the signal if clock_nanosleep is interrupted.
185 */
186 if (clock_nanosleep(CLOCK_MONOTONIC, 0, &ts, NULL)) {
187 deliver_alarm();
188 }
189 }
190