VirtualBox

source: vbox/trunk/src/VBox/Runtime/generic/timer-generic.cpp@ 9380

Last change on this file since 9380 was 9308, checked in by vboxsync, 17 years ago

Comment.
  • Property svn:eol-style set to native
  • Property svn:keywords set to Id
File size: 9.5 KB
Line 
1/** $Id: timer-generic.cpp 9308 2008-06-02 15:08:15Z vboxsync $ */
2/** @file
3 * IPRT - Timers, Generic.
4 */
5
6/*
7 * Copyright (C) 2006-2007 Sun Microsystems, Inc.
8 *
9 * This file is part of VirtualBox Open Source Edition (OSE), as
10 * available from http://www.virtualbox.org. This file is free software;
11 * you can redistribute it and/or modify it under the terms of the GNU
12 * General Public License (GPL) as published by the Free Software
13 * Foundation, in version 2 as it comes in the "COPYING" file of the
14 * VirtualBox OSE distribution. VirtualBox OSE is distributed in the
15 * hope that it will be useful, but WITHOUT ANY WARRANTY of any kind.
16 *
17 * The contents of this file may alternatively be used under the terms
18 * of the Common Development and Distribution License Version 1.0
19 * (CDDL) only, as it comes in the "COPYING.CDDL" file of the
20 * VirtualBox OSE distribution, in which case the provisions of the
21 * CDDL are applicable instead of those of the GPL.
22 *
23 * You may elect to license modified versions of this file under the
24 * terms and conditions of either the GPL or the CDDL or both.
25 *
26 * Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa
27 * Clara, CA 95054 USA or visit http://www.sun.com if you need
28 * additional information or have any questions.
29 */
30
31
32/*******************************************************************************
33* Header Files *
34*******************************************************************************/
35#include <iprt/timer.h>
36#include <iprt/thread.h>
37#include <iprt/err.h>
38#include <iprt/assert.h>
39#include <iprt/alloc.h>
40#include <iprt/asm.h>
41#include <iprt/semaphore.h>
42#include <iprt/time.h>
43#include <iprt/log.h>
44#include "internal/magics.h"
45
46
47
48/*******************************************************************************
49* Structures and Typedefs *
50*******************************************************************************/
51/**
52 * The internal representation of a timer handle.
53 */
54typedef struct RTTIMER
55{
56 /** Magic.
57 * This is RTTIMER_MAGIC, but changes to something else before the timer
58 * is destroyed to indicate clearly that thread should exit. */
59 uint32_t volatile u32Magic;
60 /** Flag indicating the the timer is suspended. */
61 uint8_t volatile fSuspended;
62 /** Flag indicating that the timer has been destroyed. */
63 uint8_t volatile fDestroyed;
64 /** Callback. */
65 PFNRTTIMER pfnTimer;
66 /** User argument. */
67 void *pvUser;
68 /** The timer thread. */
69 RTTHREAD Thread;
70 /** Event semaphore on which the thread is blocked. */
71 RTSEMEVENT Event;
72 /** The timer interval. 0 if one-shot. */
73 uint64_t u64NanoInterval;
74 /** The start of the current run (ns).
75 * This is used to calculate when the timer ought to fire the next time. */
76 uint64_t volatile u64StartTS;
77 /** The start of the current run (ns).
78 * This is used to calculate when the timer ought to fire the next time. */
79 uint64_t volatile u64NextTS;
80 /** The current tick number (since u64StartTS). */
81 uint64_t volatile iTick;
82} RTTIMER;
83
84
85/*******************************************************************************
86* Internal Functions *
87*******************************************************************************/
88static DECLCALLBACK(int) rtTimerThread(RTTHREAD Thread, void *pvUser);
89
90
91RTDECL(int) RTTimerCreateEx(PRTTIMER *ppTimer, uint64_t u64NanoInterval, unsigned fFlags, PFNRTTIMER pfnTimer, void *pvUser)
92{
93 *ppTimer = NULL;
94
95 /*
96 * Allocate and initialize the timer handle.
97 */
98 PRTTIMER pTimer = (PRTTIMER)RTMemAlloc(sizeof(*pTimer));
99 if (!pTimer)
100 return VERR_NO_MEMORY;
101
102 pTimer->u32Magic = RTTIMER_MAGIC;
103 pTimer->fSuspended = true;
104 pTimer->fDestroyed = false;
105 pTimer->pfnTimer = pfnTimer;
106 pTimer->pvUser = pvUser;
107 pTimer->Thread = NIL_RTTHREAD;
108 pTimer->Event = NIL_RTSEMEVENT;
109 pTimer->u64NanoInterval = u64NanoInterval;
110 pTimer->u64StartTS = 0;
111
112 int rc = RTSemEventCreate(&pTimer->Event);
113 if (RT_SUCCESS(rc))
114 {
115 rc = RTThreadCreate(&pTimer->Thread, rtTimerThread, pTimer, 0, RTTHREADTYPE_TIMER, RTTHREADFLAGS_WAITABLE, "TIMER");
116 if (RT_SUCCESS(rc))
117 {
118 *ppTimer = pTimer;
119 return VINF_SUCCESS;
120 }
121
122 pTimer->u32Magic = 0;
123 RTSemEventDestroy(pTimer->Event);
124 pTimer->Event = NIL_RTSEMEVENT;
125 }
126 RTMemFree(pTimer);
127
128 return rc;
129}
130
131
132/**
133 * Validates the timer handle.
134 *
135 * @returns true if valid, false if invalid.
136 * @param pTimer The handle.
137 */
138DECLINLINE(bool) rtTimerIsValid(PRTTIMER pTimer)
139{
140 AssertReturn(VALID_PTR(pTimer), false);
141 AssertReturn(pTimer->u32Magic == RTTIMER_MAGIC, false);
142 AssertReturn(!pTimer->fDestroyed, false);
143 return true;
144}
145
146
147RTDECL(int) RTTimerDestroy(PRTTIMER pTimer)
148{
149 /* It's ok to pass NULL pointer. */
150 if (pTimer == /*NIL_RTTIMER*/ NULL)
151 return VINF_SUCCESS;
152 if (!rtTimerIsValid(pTimer))
153 return VERR_INVALID_HANDLE;
154
155 /*
156 * If the timer is active, we just flag it to self destruct on the next tick.
157 * If it's suspended we can safely set the destroy flag and signal it.
158 */
159 RTTHREAD Thread = pTimer->Thread;
160 if (!pTimer->fSuspended)
161 {
162 ASMAtomicXchgU8(&pTimer->fSuspended, true);
163 ASMAtomicXchgU8(&pTimer->fDestroyed, true);
164 }
165 else
166 {
167 ASMAtomicXchgU8(&pTimer->fDestroyed, true);
168 int rc = RTSemEventSignal(pTimer->Event);
169 if (rc == VERR_ALREADY_POSTED)
170 rc = VINF_SUCCESS;
171 AssertRC(rc);
172 }
173
174 RTThreadWait(Thread, 250, NULL);
175 return VINF_SUCCESS;
176}
177
178
179RTDECL(int) RTTimerStart(PRTTIMER pTimer, uint64_t u64First)
180{
181 if (!rtTimerIsValid(pTimer))
182 return VERR_INVALID_HANDLE;
183 if (!pTimer->fSuspended)
184 return VERR_TIMER_ACTIVE;
185
186 /*
187 * Calc when it should start fireing and give the thread a kick so it get going.
188 */
189 u64First += RTTimeNanoTS();
190 ASMAtomicXchgU64(&pTimer->iTick, 0);
191 ASMAtomicXchgU64(&pTimer->u64StartTS, u64First);
192 ASMAtomicXchgU64(&pTimer->u64NextTS, u64First);
193 ASMAtomicXchgU8(&pTimer->fSuspended, false);
194 int rc = RTSemEventSignal(pTimer->Event);
195 if (rc == VERR_ALREADY_POSTED)
196 rc = VINF_SUCCESS;
197 AssertRC(rc);
198 return rc;
199}
200
201
202RTDECL(int) RTTimerStop(PRTTIMER pTimer)
203{
204 if (!rtTimerIsValid(pTimer))
205 return VERR_INVALID_HANDLE;
206 if (pTimer->fSuspended)
207 return VERR_TIMER_SUSPENDED;
208
209 /*
210 * Mark it as suspended and kick the thread.
211 */
212 ASMAtomicXchgU8(&pTimer->fSuspended, true);
213 int rc = RTSemEventSignal(pTimer->Event);
214 if (rc == VERR_ALREADY_POSTED)
215 rc = VINF_SUCCESS;
216 AssertRC(rc);
217 return rc;
218}
219
220
221static DECLCALLBACK(int) rtTimerThread(RTTHREAD Thread, void *pvUser)
222{
223 PRTTIMER pTimer = (PRTTIMER)pvUser;
224
225 /*
226 * The loop.
227 */
228 while (!pTimer->fDestroyed)
229 {
230 if (pTimer->fSuspended)
231 {
232 int rc = RTSemEventWait(pTimer->Event, RT_INDEFINITE_WAIT);
233 if (RT_FAILURE(rc) && rc != VERR_INTERRUPTED)
234 {
235 AssertRC(rc);
236 RTThreadSleep(1000); /* Don't cause trouble! */
237 }
238 }
239 else
240 {
241 const uint64_t u64NanoTS = RTTimeNanoTS();
242 if (u64NanoTS >= pTimer->u64NextTS)
243 {
244 pTimer->iTick++;
245 pTimer->pfnTimer(pTimer, pTimer->pvUser);
246
247 /* status changed? */
248 if (pTimer->fSuspended || pTimer->fDestroyed)
249 continue;
250
251 /* one shot? */
252 if (!pTimer->u64NanoInterval)
253 {
254 ASMAtomicXchgU8(&pTimer->fSuspended, true);
255 continue;
256 }
257
258 /* calc the next time we should fire. */
259 pTimer->u64NextTS = pTimer->u64StartTS + pTimer->iTick * pTimer->u64NanoInterval;
260 if (pTimer->u64NextTS < u64NanoTS)
261#ifdef IN_RING3 /* In ring-3 we'll catch up lost ticks immediately. */
262 pTimer->u64NextTS = u64NanoTS + 1;
263#else
264 pTimer->u64NextTS = u64NanoTS + RTTimerGetSystemGranularity() / 2;
265#endif
266 }
267
268 /* block. */
269 uint64_t cNanoSeconds = pTimer->u64NextTS - u64NanoTS;
270#ifdef IN_RING3 /* In ring-3 we'll catch up lost ticks immediately. */
271 if (cNanoSeconds > 10)
272#endif
273 {
274 int rc = RTSemEventWait(pTimer->Event, cNanoSeconds < 1000000 ? 1 : cNanoSeconds / 1000000);
275 if (RT_FAILURE(rc) && rc != VERR_INTERRUPTED && rc != VERR_TIMEOUT)
276 {
277 AssertRC(rc);
278 RTThreadSleep(1000); /* Don't cause trouble! */
279 }
280 }
281 }
282 }
283
284 /*
285 * Release the timer resources.
286 */
287 ASMAtomicIncU32(&pTimer->u32Magic); /* make the handle invalid. */
288 int rc = RTSemEventDestroy(pTimer->Event); AssertRC(rc);
289 pTimer->Event = NIL_RTSEMEVENT;
290 pTimer->Thread = NIL_RTTHREAD;
291 RTMemFree(pTimer);
292
293 return VINF_SUCCESS;
294}
295
296
297
298
299RTDECL(uint32_t) RTTimerGetSystemGranularity(void)
300{
301 return 10000000; /* 10ms */
302}
303
304
305RTDECL(int) RTTimerRequestSystemGranularity(uint32_t u32Request, uint32_t *pu32Granted)
306{
307 return VERR_NOT_SUPPORTED;
308}
309
310
311RTDECL(int) RTTimerReleaseSystemGranularity(uint32_t u32Granted)
312{
313 return VERR_NOT_SUPPORTED;
314}
315
Note: See TracBrowser for help on using the repository browser.

© 2024 Oracle Support Privacy / Do Not Sell My Info Terms of Use Trademark Policy Automated Access Etiquette