1 /**************************************************************************
2 *
3 * Copyright 2008-2010 VMware, Inc.
4 * All Rights Reserved.
5 *
6 * Permission is hereby granted, free of charge, to any person obtaining a
7 * copy of this software and associated documentation files (the
8 * "Software"), to deal in the Software without restriction, including
9 * without limitation the rights to use, copy, modify, merge, publish,
10 * distribute, sub license, and/or sell copies of the Software, and to
11 * permit persons to whom the Software is furnished to do so, subject to
12 * the following conditions:
13 *
14 * The above copyright notice and this permission notice (including the
15 * next paragraph) shall be included in all copies or substantial portions
16 * of the Software.
17 *
18 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
19 * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
20 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT.
21 * IN NO EVENT SHALL VMWARE AND/OR ITS SUPPLIERS BE LIABLE FOR
22 * ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT,
23 * TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE
24 * SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
25 *
26 **************************************************************************/
27
28 /**
29 * @file
30 * OS independent time-manipulation functions.
31 *
32 * @author Jose Fonseca <jfonseca@vmware.com>
33 */
34
35
36 #include "pipe/p_defines.h"
37 #include "util/u_atomic.h"
38
39 #if defined(PIPE_OS_UNIX)
40 # include <time.h> /* timeval */
41 # include <sys/time.h> /* timeval */
42 # include <sched.h> /* sched_yield */
43 # include <errno.h>
44 #elif defined(PIPE_SUBSYSTEM_WINDOWS_USER)
45 # include <windows.h>
46 #else
47 # error Unsupported OS
48 #endif
49
50 #include "os_time.h"
51
52
53 int64_t
os_time_get_nano(void)54 os_time_get_nano(void)
55 {
56 #if defined(PIPE_OS_LINUX)
57
58 struct timespec tv;
59 clock_gettime(CLOCK_MONOTONIC, &tv);
60 return tv.tv_nsec + tv.tv_sec*INT64_C(1000000000);
61
62 #elif defined(PIPE_OS_UNIX)
63
64 struct timeval tv;
65 gettimeofday(&tv, NULL);
66 return tv.tv_usec*INT64_C(1000) + tv.tv_sec*INT64_C(1000000000);
67
68 #elif defined(PIPE_SUBSYSTEM_WINDOWS_USER)
69
70 static LARGE_INTEGER frequency;
71 LARGE_INTEGER counter;
72 if(!frequency.QuadPart)
73 QueryPerformanceFrequency(&frequency);
74 QueryPerformanceCounter(&counter);
75 return counter.QuadPart*INT64_C(1000000000)/frequency.QuadPart;
76
77 #else
78
79 #error Unsupported OS
80
81 #endif
82 }
83
84
85
86 void
os_time_sleep(int64_t usecs)87 os_time_sleep(int64_t usecs)
88 {
89 #if defined(PIPE_OS_LINUX)
90 struct timespec time;
91 time.tv_sec = usecs / 1000000;
92 time.tv_nsec = (usecs % 1000000) * 1000;
93 while (clock_nanosleep(CLOCK_MONOTONIC, 0, &time, &time) == EINTR);
94
95 #elif defined(PIPE_OS_UNIX)
96 usleep(usecs);
97
98 #elif defined(PIPE_SUBSYSTEM_WINDOWS_USER)
99 DWORD dwMilliseconds = (DWORD) ((usecs + 999) / 1000);
100 /* Avoid Sleep(O) as that would cause to sleep for an undetermined duration */
101 if (dwMilliseconds) {
102 Sleep(dwMilliseconds);
103 }
104 #else
105 # error Unsupported OS
106 #endif
107 }
108
109
110
111 int64_t
os_time_get_absolute_timeout(uint64_t timeout)112 os_time_get_absolute_timeout(uint64_t timeout)
113 {
114 int64_t time, abs_timeout;
115
116 /* Also check for the type upper bound. */
117 if (timeout == PIPE_TIMEOUT_INFINITE || timeout > INT64_MAX)
118 return PIPE_TIMEOUT_INFINITE;
119
120 time = os_time_get_nano();
121 abs_timeout = time + (int64_t)timeout;
122
123 /* Check for overflow. */
124 if (abs_timeout < time)
125 return PIPE_TIMEOUT_INFINITE;
126
127 return abs_timeout;
128 }
129
130
131 bool
os_wait_until_zero(volatile int * var,uint64_t timeout)132 os_wait_until_zero(volatile int *var, uint64_t timeout)
133 {
134 if (!p_atomic_read(var))
135 return true;
136
137 if (!timeout)
138 return false;
139
140 if (timeout == PIPE_TIMEOUT_INFINITE) {
141 while (p_atomic_read(var)) {
142 #if defined(PIPE_OS_UNIX)
143 sched_yield();
144 #endif
145 }
146 return true;
147 }
148 else {
149 int64_t start_time = os_time_get_nano();
150 int64_t end_time = start_time + timeout;
151
152 while (p_atomic_read(var)) {
153 if (os_time_timeout(start_time, end_time, os_time_get_nano()))
154 return false;
155
156 #if defined(PIPE_OS_UNIX)
157 sched_yield();
158 #endif
159 }
160 return true;
161 }
162 }
163
164
165 bool
os_wait_until_zero_abs_timeout(volatile int * var,int64_t timeout)166 os_wait_until_zero_abs_timeout(volatile int *var, int64_t timeout)
167 {
168 if (!p_atomic_read(var))
169 return true;
170
171 if (timeout == PIPE_TIMEOUT_INFINITE)
172 return os_wait_until_zero(var, PIPE_TIMEOUT_INFINITE);
173
174 while (p_atomic_read(var)) {
175 if (os_time_get_nano() >= timeout)
176 return false;
177
178 #if defined(PIPE_OS_UNIX)
179 sched_yield();
180 #endif
181 }
182 return true;
183 }
184