blob: 0710788c023f3bfb7834f07dabc651a77816b0f5 (
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
|
/*************************************************************************
* Copyright (C) 2008 Tavian Barnes <tavianator@gmail.com> *
* *
* This file is part of The Sandglass Library. *
* *
* The Sandglass Library 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 *
* 3 of the License, or (at your option) any later version. *
* *
* The Sandglass Library 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 this program. If not, see *
* <http://www.gnu.org/licenses/>. *
*************************************************************************/
#include "sandglass_impl.h"
#include "sandglass.h"
#include <unistd.h>
#include <time.h>
#include <errno.h>
int
sandglass_init_introspective(sandglass_t *sandglass, sandglass_resolution_t res)
{
switch (res) {
case SANDGLASS_CPUTIME:
if (sysconf(_SC_THREAD_CPUTIME) > 0 || sysconf(_SC_CPUTIME) > 0) {
sandglass->freq = 1e9;
sandglass->loops = 1;
} else {
errno = ENOTSUP;
return -1;
}
break;
case SANDGLASS_SYSTEM:
sandglass->freq = CLOCKS_PER_SEC;
sandglass->loops = 1;
break;
default:
errno = EINVAL;
return -1;
}
sandglass->incrementation = SANDGLASS_INTROSPECTIVE;
sandglass->resolution = res;
return 0;
}
int
sandglass_init_monotonic(sandglass_t *sandglass, sandglass_resolution_t res)
{
switch (res) {
case SANDGLASS_CPUTIME:
#if SANDGLASS_TSC
sandglass->freq = sandglass_tsc_freq();
sandglass->loops = sandglass_tsc_loops();
break;
#else
errno = ENOTSUP;
return -1;
#endif
case SANDGLASS_SYSTEM:
sandglass->freq = 1e9;
sandglass->loops = 1;
break;
default:
errno = EINVAL;
return -1;
}
sandglass->incrementation = SANDGLASS_MONOTONIC;
sandglass->resolution = res;
return 0;
}
/* Store a timer value in sandglass->grains */
static int sandglass_real_gettime(sandglass_t *sandglass);
/* Start timing */
int
sandglass_begin(sandglass_t *sandglass)
{
return sandglass_real_gettime(sandglass);
}
/* Finish timing */
int
sandglass_elapse(sandglass_t *sandglass)
{
long oldgrains = sandglass->grains;
if (sandglass_real_gettime(sandglass))
return -1;
sandglass->grains -= oldgrains;
if (sandglass->grains < 0)
/* Magical correction for timespec-based grains */
sandglass->grains += sandglass->adjustment;
return 0;
}
/* Store a timer value in sandglass->grains */
static int
sandglass_real_gettime(sandglass_t *sandglass)
{
struct timespec ts;
clock_t clock_ticks;
switch (sandglass->incrementation) {
case SANDGLASS_MONOTONIC:
switch (sandglass->resolution) {
case SANDGLASS_CPUTIME:
#if SANDGLASS_TSC
sandglass->grains = sandglass_get_tsc();
break;
#else
errno = ENOTSUP;
return -1;
#endif
case SANDGLASS_SYSTEM:
if (sysconf(_SC_MONOTONIC_CLOCK) > 0) {
if (clock_gettime(CLOCK_MONOTONIC, &ts) != 0)
return -1;
} else {
if (clock_gettime(CLOCK_REALTIME, &ts) != 0)
return -1;
}
sandglass->grains = ts.tv_nsec;
sandglass->adjustment = 1000000000L;
break;
default:
errno = EINVAL;
return -1;
}
break;
case SANDGLASS_INTROSPECTIVE:
switch (sandglass->resolution) {
case SANDGLASS_CPUTIME:
if (sysconf(_SC_THREAD_CPUTIME) > 0) {
if (clock_gettime(CLOCK_THREAD_CPUTIME_ID, &ts) != 0)
return -1;
} else if (sysconf(_SC_CPUTIME) > 0) {
if (clock_gettime(CLOCK_PROCESS_CPUTIME_ID, &ts) != 0)
return -1;
} else {
errno = EINVAL;
return -1;
}
sandglass->grains = ts.tv_nsec;
sandglass->adjustment = 1000000000L;
break;
case SANDGLASS_SYSTEM:
if ((clock_ticks = clock()) == -1)
return -1;
sandglass->grains = clock_ticks;
break;
default:
errno = EINVAL;
return -1;
}
break;
default:
errno = EINVAL;
return -1;
}
return 0;
}
|
