summaryrefslogtreecommitdiff
path: root/src/pulsecore/core-rtclock.c
blob: 6632cc6deeaad223bcc59a41a4149a29e36bdb9b (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
/***
  This file is part of PulseAudio.

  Copyright 2004-2006 Lennart Poettering
  Copyright 2006 Pierre Ossman <ossman@cendio.se> for Cendio AB

  PulseAudio is free software; you can redistribute it and/or modify
  it under the terms of the GNU Lesser General Public License as
  published by the Free Software Foundation; either version 2.1 of the
  License, or (at your option) any later version.

  PulseAudio is distributed in the hope that it will be useful, but
  WITHOUT ANY WARRANTY; without even the implied warranty of
  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
  Lesser General Public License for more details.

  You should have received a copy of the GNU Lesser General Public
  License along with PulseAudio; if not, write to the Free Software
  Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307
  USA.
***/

#ifdef HAVE_CONFIG_H
#include <config.h>
#endif

#ifdef OS_IS_DARWIN
#define _POSIX_C_SOURCE 1
#endif

#include <stddef.h>
#include <time.h>
#include <sys/time.h>
#include <errno.h>

#ifdef HAVE_SYS_PRCTL_H
#include <sys/prctl.h>
#endif

#ifdef OS_IS_DARWIN
#include <CoreServices/CoreServices.h>
#include <mach/mach.h>
#include <mach/mach_time.h>
#include <unistd.h>
#endif

#ifdef HAVE_WINDOWS_H
#include <windows.h>
#endif

#include <pulse/timeval.h>
#include <pulsecore/macro.h>
#include <pulsecore/core-error.h>

#include "core-rtclock.h"

#ifdef OS_IS_WIN32
static int64_t counter_freq = 0;
#endif

pa_usec_t pa_rtclock_age(const struct timeval *tv) {
    struct timeval now;
    pa_assert(tv);

    return pa_timeval_diff(pa_rtclock_get(&now), tv);
}

struct timeval *pa_rtclock_get(struct timeval *tv) {

#if defined(OS_IS_DARWIN)
    uint64_t val, abs_time = mach_absolute_time();
    Nanoseconds nanos;

    nanos = AbsoluteToNanoseconds(*(AbsoluteTime *) &abs_time);
    val = *(uint64_t *) &nanos;

    tv->tv_sec = val / PA_NSEC_PER_SEC;
    tv->tv_usec = (val % PA_NSEC_PER_SEC) / PA_NSEC_PER_USEC;

    return tv;

#elif defined(HAVE_CLOCK_GETTIME)
    struct timespec ts;

#ifdef CLOCK_MONOTONIC
    /* No locking or atomic ops for no_monotonic here */
    static pa_bool_t no_monotonic = FALSE;

    if (!no_monotonic)
        if (clock_gettime(CLOCK_MONOTONIC, &ts) < 0)
            no_monotonic = TRUE;

    if (no_monotonic)
#endif /* CLOCK_MONOTONIC */
        pa_assert_se(clock_gettime(CLOCK_REALTIME, &ts) == 0);

    pa_assert(tv);

    tv->tv_sec = ts.tv_sec;
    tv->tv_usec = ts.tv_nsec / PA_NSEC_PER_USEC;

    return tv;
#elif defined(OS_IS_WIN32)
    if (counter_freq > 0) {
        LARGE_INTEGER count;

        pa_assert_se(QueryPerformanceCounter(&count));

        tv->tv_sec = count.QuadPart / counter_freq;
        tv->tv_usec = (count.QuadPart % counter_freq) * PA_USEC_PER_SEC / counter_freq;

        return tv;
    }
#endif /* HAVE_CLOCK_GETTIME */

    return pa_gettimeofday(tv);
}

pa_bool_t pa_rtclock_hrtimer(void) {

#if defined (OS_IS_DARWIN)
    mach_timebase_info_data_t tbi;
    uint64_t time_nsec;

    mach_timebase_info(&tbi);

    /* nsec = nticks * (N/D) - we want 1 tick == resolution !? */
    time_nsec = tbi.numer / tbi.denom;
    return time_nsec <= (long) (PA_HRTIMER_THRESHOLD_USEC*PA_NSEC_PER_USEC);

#elif defined(HAVE_CLOCK_GETTIME)
    struct timespec ts;

#ifdef CLOCK_MONOTONIC

    if (clock_getres(CLOCK_MONOTONIC, &ts) >= 0)
        return ts.tv_sec == 0 && ts.tv_nsec <= (long) (PA_HRTIMER_THRESHOLD_USEC*PA_NSEC_PER_USEC);

#endif /* CLOCK_MONOTONIC */

    pa_assert_se(clock_getres(CLOCK_REALTIME, &ts) == 0);
    return ts.tv_sec == 0 && ts.tv_nsec <= (long) (PA_HRTIMER_THRESHOLD_USEC*PA_NSEC_PER_USEC);

#elif defined(OS_IS_WIN32)

    if (counter_freq > 0)
        return counter_freq >= (int64_t) (PA_USEC_PER_SEC/PA_HRTIMER_THRESHOLD_USEC);

#endif /* HAVE_CLOCK_GETTIME */

    return FALSE;
}

#define TIMER_SLACK_NS (int) ((500 * PA_NSEC_PER_USEC))

void pa_rtclock_hrtimer_enable(void) {

#ifdef PR_SET_TIMERSLACK
    int slack_ns;

    if ((slack_ns = prctl(PR_GET_TIMERSLACK, 0, 0, 0, 0)) < 0) {
        pa_log_info("PR_GET_TIMERSLACK/PR_SET_TIMERSLACK not supported.");
        return;
    }

    pa_log_debug("Timer slack is set to %i us.", (int) (slack_ns/PA_NSEC_PER_USEC));

    if (slack_ns > TIMER_SLACK_NS) {
        slack_ns = TIMER_SLACK_NS;

        pa_log_debug("Setting timer slack to %i us.", (int) (slack_ns/PA_NSEC_PER_USEC));

        if (prctl(PR_SET_TIMERSLACK, slack_ns, 0, 0, 0) < 0) {
            pa_log_warn("PR_SET_TIMERSLACK failed: %s", pa_cstrerror(errno));
            return;
        }
    }

#elif defined(OS_IS_WIN32)
    LARGE_INTEGER freq;

    pa_assert_se(QueryPerformanceFrequency(&freq));
    counter_freq = freq.QuadPart;

#endif
}

struct timeval* pa_rtclock_from_wallclock(struct timeval *tv) {
    struct timeval wc_now, rt_now;

    pa_assert(tv);

    pa_gettimeofday(&wc_now);
    pa_rtclock_get(&rt_now);

    /* pa_timeval_sub() saturates on underflow! */

    if (pa_timeval_cmp(&wc_now, tv) < 0)
        pa_timeval_add(&rt_now, pa_timeval_diff(tv, &wc_now));
    else
        pa_timeval_sub(&rt_now, pa_timeval_diff(&wc_now, tv));

    *tv = rt_now;

    return tv;
}

#ifdef HAVE_CLOCK_GETTIME
pa_usec_t pa_timespec_load(const struct timespec *ts) {

    if (PA_UNLIKELY(!ts))
        return PA_USEC_INVALID;

    return
        (pa_usec_t) ts->tv_sec * PA_USEC_PER_SEC +
        (pa_usec_t) ts->tv_nsec / PA_NSEC_PER_USEC;
}

struct timespec* pa_timespec_store(struct timespec *ts, pa_usec_t v) {
    pa_assert(ts);

    if (PA_UNLIKELY(v == PA_USEC_INVALID)) {
        ts->tv_sec = PA_INT_TYPE_MAX(time_t);
        ts->tv_nsec = (long) (PA_NSEC_PER_SEC-1);
        return NULL;
    }

    ts->tv_sec = (time_t) (v / PA_USEC_PER_SEC);
    ts->tv_nsec = (long) ((v % PA_USEC_PER_SEC) * PA_NSEC_PER_USEC);

    return ts;
}
#endif

static struct timeval* wallclock_from_rtclock(struct timeval *tv) {
    struct timeval wc_now, rt_now;

    pa_assert(tv);

    pa_gettimeofday(&wc_now);
    pa_rtclock_get(&rt_now);

    /* pa_timeval_sub() saturates on underflow! */

    if (pa_timeval_cmp(&rt_now, tv) < 0)
        pa_timeval_add(&wc_now, pa_timeval_diff(tv, &rt_now));
    else
        pa_timeval_sub(&wc_now, pa_timeval_diff(&rt_now, tv));

    *tv = wc_now;

    return tv;
}

struct timeval* pa_timeval_rtstore(struct timeval *tv, pa_usec_t v, pa_bool_t rtclock) {
    pa_assert(tv);

    if (v == PA_USEC_INVALID)
        return NULL;

    pa_timeval_store(tv, v);

    if (rtclock)
        tv->tv_usec |= PA_TIMEVAL_RTCLOCK;
    else
        wallclock_from_rtclock(tv);

    return tv;
}