TMAllVirtual.cpp@ 23794

Last change on this file since 23794 was 22890, checked in by vboxsync, 15 years ago
VM::cCPUs -> VM::cCpus so it matches all the other cCpus and aCpus members.
Property svn:eol-style set to `native` Property svn:keywords set to `Id`
File size: 32.1 KB

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1	/* $Id: TMAllVirtual.cpp 22890 2009-09-09 23:11:31Z vboxsync $ */
2	/** @file
3	* TM - Timeout Manager, Virtual Time, All Contexts.
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	* Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa
18	* Clara, CA 95054 USA or visit http://www.sun.com if you need
19	* additional information or have any questions.
20	*/
21
22
23	/*******************************************************************************
24	* Header Files *
25	*******************************************************************************/
26	#define LOG_GROUP LOG_GROUP_TM
27	#include <VBox/tm.h>
28	#ifdef IN_RING3
29	# include <VBox/rem.h>
30	# include <iprt/thread.h>
31	#endif
32	#include "TMInternal.h"
33	#include <VBox/vm.h>
34	#include <VBox/vmm.h>
35	#include <VBox/err.h>
36	#include <VBox/log.h>
37	#include <VBox/sup.h>
38
39	#include <iprt/time.h>
40	#include <iprt/assert.h>
41	#include <iprt/asm.h>
42
43
44
45	/**
46	* Helper function that's used by the assembly routines when something goes bust.
47	*
48	* @param pData Pointer to the data structure.
49	* @param u64NanoTS The calculated nano ts.
50	* @param u64DeltaPrev The delta relative to the previously returned timestamp.
51	* @param u64PrevNanoTS The previously returned timestamp (as it was read it).
52	*/
53	DECLEXPORT(void) tmVirtualNanoTSBad(PRTTIMENANOTSDATA pData, uint64_t u64NanoTS, uint64_t u64DeltaPrev, uint64_t u64PrevNanoTS)
54	{
55	//PVM pVM = (PVM)((uint8_t *)pData - RT_OFFSETOF(VM, CTXALLSUFF(s.tm.VirtualGetRawData)));
56	pData->cBadPrev++;
57	if ((int64_t)u64DeltaPrev < 0)
58	LogRel(("TM: u64DeltaPrev=%RI64 u64PrevNanoTS=0x%016RX64 u64NanoTS=0x%016RX64\n",
59	u64DeltaPrev, u64PrevNanoTS, u64NanoTS));
60	else
61	Log(("TM: u64DeltaPrev=%RI64 u64PrevNanoTS=0x%016RX64 u64NanoTS=0x%016RX64 (debugging?)\n",
62	u64DeltaPrev, u64PrevNanoTS, u64NanoTS));
63	}
64
65
66	/**
67	* Called the first time somebody asks for the time or when the GIP
68	* is mapped/unmapped.
69	*
70	* This should never ever happen.
71	*/
72	DECLEXPORT(uint64_t) tmVirtualNanoTSRediscover(PRTTIMENANOTSDATA pData)
73	{
74	//PVM pVM = (PVM)((uint8_t *)pData - RT_OFFSETOF(VM, CTXALLSUFF(s.tm.VirtualGetRawData)));
75	PSUPGLOBALINFOPAGE pGip = g_pSUPGlobalInfoPage;
76	AssertFatalMsgFailed(("pGip=%p u32Magic=%#x\n", pGip, VALID_PTR(pGip) ? pGip->u32Magic : 0));
77	}
78
79
80	#if 1
81
82	/**
83	* Wrapper around the IPRT GIP time methods.
84	*/
85	DECLINLINE(uint64_t) tmVirtualGetRawNanoTS(PVM pVM)
86	{
87	#ifdef IN_RING3
88	return CTXALLSUFF(pVM->tm.s.pfnVirtualGetRaw)(&CTXALLSUFF(pVM->tm.s.VirtualGetRawData));
89	# else /* !IN_RING3 */
90	uint32_t cPrevSteps = pVM->tm.s.CTX_SUFF(VirtualGetRawData).c1nsSteps;
91	uint64_t u64 = pVM->tm.s.CTX_SUFF(pfnVirtualGetRaw)(&pVM->tm.s.CTX_SUFF(VirtualGetRawData));
92	if (cPrevSteps != pVM->tm.s.CTX_SUFF(VirtualGetRawData).c1nsSteps)
93	VMCPU_FF_SET(VMMGetCpu(pVM), VMCPU_FF_TO_R3);
94	return u64;
95	# endif /* !IN_RING3 */
96	}
97
98	#else
99
100	/**
101	* This is (mostly) the same as rtTimeNanoTSInternal() except
102	* for the two globals which live in TM.
103	*
104	* @returns Nanosecond timestamp.
105	* @param pVM The VM handle.
106	*/
107	static uint64_t tmVirtualGetRawNanoTS(PVM pVM)
108	{
109	uint64_t u64Delta;
110	uint32_t u32NanoTSFactor0;
111	uint64_t u64TSC;
112	uint64_t u64NanoTS;
113	uint32_t u32UpdateIntervalTSC;
114	uint64_t u64PrevNanoTS;
115
116	/*
117	* Read the GIP data and the previous value.
118	*/
119	for (;;)
120	{
121	uint32_t u32TransactionId;
122	PSUPGLOBALINFOPAGE pGip = g_pSUPGlobalInfoPage;
123	#ifdef IN_RING3
124	if (RT_UNLIKELY(!pGip \|\| pGip->u32Magic != SUPGLOBALINFOPAGE_MAGIC))
125	return RTTimeSystemNanoTS();
126	#endif
127
128	if (pGip->u32Mode != SUPGIPMODE_ASYNC_TSC)
129	{
130	u32TransactionId = pGip->aCPUs[0].u32TransactionId;
131	#ifdef RT_OS_L4
132	Assert((u32TransactionId & 1) == 0);
133	#endif
134	u32UpdateIntervalTSC = pGip->aCPUs[0].u32UpdateIntervalTSC;
135	u64NanoTS = pGip->aCPUs[0].u64NanoTS;
136	u64TSC = pGip->aCPUs[0].u64TSC;
137	u32NanoTSFactor0 = pGip->u32UpdateIntervalNS;
138	u64Delta = ASMReadTSC();
139	u64PrevNanoTS = ASMAtomicReadU64(&pVM->tm.s.u64VirtualRawPrev);
140	if (RT_UNLIKELY( pGip->aCPUs[0].u32TransactionId != u32TransactionId
141	\|\| (u32TransactionId & 1)))
142	continue;
143	}
144	else
145	{
146	/* SUPGIPMODE_ASYNC_TSC */
147	PSUPGIPCPU pGipCpu;
148
149	uint8_t u8ApicId = ASMGetApicId();
150	if (RT_LIKELY(u8ApicId < RT_ELEMENTS(pGip->aCPUs)))
151	pGipCpu = &pGip->aCPUs[u8ApicId];
152	else
153	{
154	AssertMsgFailed(("%x\n", u8ApicId));
155	pGipCpu = &pGip->aCPUs[0];
156	}
157
158	u32TransactionId = pGipCpu->u32TransactionId;
159	#ifdef RT_OS_L4
160	Assert((u32TransactionId & 1) == 0);
161	#endif
162	u32UpdateIntervalTSC = pGipCpu->u32UpdateIntervalTSC;
163	u64NanoTS = pGipCpu->u64NanoTS;
164	u64TSC = pGipCpu->u64TSC;
165	u32NanoTSFactor0 = pGip->u32UpdateIntervalNS;
166	u64Delta = ASMReadTSC();
167	u64PrevNanoTS = ASMAtomicReadU64(&pVM->tm.s.u64VirtualRawPrev);
168	#ifdef IN_RC
169	Assert(!(ASMGetFlags() & X86_EFL_IF));
170	#else
171	if (RT_UNLIKELY(u8ApicId != ASMGetApicId()))
172	continue;
173	if (RT_UNLIKELY( pGipCpu->u32TransactionId != u32TransactionId
174	\|\| (u32TransactionId & 1)))
175	continue;
176	#endif
177	}
178	break;
179	}
180
181	/*
182	* Calc NanoTS delta.
183	*/
184	u64Delta -= u64TSC;
185	if (u64Delta > u32UpdateIntervalTSC)
186	{
187	/*
188	* We've expired the interval, cap it. If we're here for the 2nd
189	* time without any GIP update inbetween, the checks against
190	* pVM->tm.s.u64VirtualRawPrev below will force 1ns stepping.
191	*/
192	u64Delta = u32UpdateIntervalTSC;
193	}
194	#if !defined(_MSC_VER) \|\| defined(RT_ARCH_AMD64) /* GCC makes very pretty code from these two inline calls, while MSC cannot. */
195	u64Delta = ASMMult2xU32RetU64((uint32_t)u64Delta, u32NanoTSFactor0);
196	u64Delta = ASMDivU64ByU32RetU32(u64Delta, u32UpdateIntervalTSC);
197	#else
198	__asm
199	{
200	mov eax, dword ptr [u64Delta]
201	mul dword ptr [u32NanoTSFactor0]
202	div dword ptr [u32UpdateIntervalTSC]
203	mov dword ptr [u64Delta], eax
204	xor edx, edx
205	mov dword ptr [u64Delta + 4], edx
206	}
207	#endif
208
209	/*
210	* Calculate the time and compare it with the previously returned value.
211	*
212	* Since this function is called very frequently when the VM is running
213	* and then mostly on EMT, we can restrict the valid range of the delta
214	* (-1s to 2*GipUpdates) and simplify/optimize the default path.
215	*/
216	u64NanoTS += u64Delta;
217	uint64_t u64DeltaPrev = u64NanoTS - u64PrevNanoTS;
218	if (RT_LIKELY(u64DeltaPrev < 1000000000 /* 1s */))
219	/* frequent - less than 1s since last call. */;
220	else if ( (int64_t)u64DeltaPrev < 0
221	&& (int64_t)u64DeltaPrev + u32NanoTSFactor0 * 2 > 0)
222	{
223	/* occasional - u64NanoTS is in the 'past' relative to previous returns. */
224	ASMAtomicIncU32(&pVM->tm.s.CTX_SUFF(VirtualGetRawData).c1nsSteps);
225	u64NanoTS = u64PrevNanoTS + 1;
226	#ifndef IN_RING3
227	VM_FF_SET(pVM, VM_FF_TO_R3); /* S10 hack */
228	#endif
229	}
230	else if (u64PrevNanoTS)
231	{
232	/* Something has gone bust, if negative offset it's real bad. */
233	ASMAtomicIncU32(&pVM->tm.s.CTX_SUFF(VirtualGetRawData).cBadPrev);
234	if ((int64_t)u64DeltaPrev < 0)
235	LogRel(("TM: u64DeltaPrev=%RI64 u64PrevNanoTS=0x%016RX64 u64NanoTS=0x%016RX64 u64Delta=%#RX64\n",
236	u64DeltaPrev, u64PrevNanoTS, u64NanoTS, u64Delta));
237	else
238	Log(("TM: u64DeltaPrev=%RI64 u64PrevNanoTS=0x%016RX64 u64NanoTS=0x%016RX64 u64Delta=%#RX64 (debugging?)\n",
239	u64DeltaPrev, u64PrevNanoTS, u64NanoTS, u64Delta));
240	#ifdef DEBUG_bird
241	/** @todo there are some hickups during boot and reset that can cause 2-5 seconds delays. Investigate... */
242	AssertMsg(u64PrevNanoTS > UINT64_C(100000000000) /* 100s */,
243	("u64DeltaPrev=%RI64 u64PrevNanoTS=0x%016RX64 u64NanoTS=0x%016RX64 u64Delta=%#RX64\n",
244	u64DeltaPrev, u64PrevNanoTS, u64NanoTS, u64Delta));
245	#endif
246	}
247	/* else: We're resuming (see TMVirtualResume). */
248	if (RT_LIKELY(ASMAtomicCmpXchgU64(&pVM->tm.s.u64VirtualRawPrev, u64NanoTS, u64PrevNanoTS)))
249	return u64NanoTS;
250
251	/*
252	* Attempt updating the previous value, provided we're still ahead of it.
253	*
254	* There is no point in recalculating u64NanoTS because we got preemted or if
255	* we raced somebody while the GIP was updated, since these are events
256	* that might occure at any point in the return path as well.
257	*/
258	for (int cTries = 50;;)
259	{
260	u64PrevNanoTS = ASMAtomicReadU64(&pVM->tm.s.u64VirtualRawPrev);
261	if (u64PrevNanoTS >= u64NanoTS)
262	break;
263	if (ASMAtomicCmpXchgU64(&pVM->tm.s.u64VirtualRawPrev, u64NanoTS, u64PrevNanoTS))
264	break;
265	AssertBreak(--cTries <= 0);
266	if (cTries < 25 && !VM_IS_EMT(pVM)) /* give up early */
267	break;
268	}
269
270	return u64NanoTS;
271	}
272
273	#endif
274
275
276	/**
277	* Get the time when we're not running at 100%
278	*
279	* @returns The timestamp.
280	* @param pVM The VM handle.
281	*/
282	static uint64_t tmVirtualGetRawNonNormal(PVM pVM)
283	{
284	/*
285	* Recalculate the RTTimeNanoTS() value for the period where
286	* warp drive has been enabled.
287	*/
288	uint64_t u64 = tmVirtualGetRawNanoTS(pVM);
289	u64 -= pVM->tm.s.u64VirtualWarpDriveStart;
290	u64 *= pVM->tm.s.u32VirtualWarpDrivePercentage;
291	u64 /= 100;
292	u64 += pVM->tm.s.u64VirtualWarpDriveStart;
293
294	/*
295	* Now we apply the virtual time offset.
296	* (Which is the negated tmVirtualGetRawNanoTS() value for when the virtual
297	* machine started if it had been running continuously without any suspends.)
298	*/
299	u64 -= pVM->tm.s.u64VirtualOffset;
300	return u64;
301	}
302
303
304	/**
305	* Get the raw virtual time.
306	*
307	* @returns The current time stamp.
308	* @param pVM The VM handle.
309	*/
310	DECLINLINE(uint64_t) tmVirtualGetRaw(PVM pVM)
311	{
312	if (RT_LIKELY(!pVM->tm.s.fVirtualWarpDrive))
313	return tmVirtualGetRawNanoTS(pVM) - pVM->tm.s.u64VirtualOffset;
314	return tmVirtualGetRawNonNormal(pVM);
315	}
316
317
318	/**
319	* Inlined version of tmVirtualGetEx.
320	*/
321	DECLINLINE(uint64_t) tmVirtualGet(PVM pVM, bool fCheckTimers)
322	{
323	uint64_t u64;
324	if (RT_LIKELY(pVM->tm.s.cVirtualTicking))
325	{
326	STAM_COUNTER_INC(&pVM->tm.s.StatVirtualGet);
327	u64 = tmVirtualGetRaw(pVM);
328
329	/*
330	* Use the chance to check for expired timers.
331	*/
332	if (fCheckTimers)
333	{
334	PVMCPU pVCpuDst = &pVM->aCpus[pVM->tm.s.idTimerCpu];
335	if ( !VMCPU_FF_ISSET(pVCpuDst, VMCPU_FF_TIMER)
336	&& !pVM->tm.s.fRunningQueues
337	&& ( pVM->tm.s.CTX_SUFF(paTimerQueues)[TMCLOCK_VIRTUAL].u64Expire <= u64
338	\|\| ( pVM->tm.s.fVirtualSyncTicking
339	&& pVM->tm.s.CTX_SUFF(paTimerQueues)[TMCLOCK_VIRTUAL_SYNC].u64Expire <= u64 - pVM->tm.s.offVirtualSync
340	)
341	)
342	&& !pVM->tm.s.fRunningQueues
343	)
344	{
345	STAM_COUNTER_INC(&pVM->tm.s.StatVirtualGetSetFF);
346	Log5(("TMAllVirtual(%u): FF: %d -> 1\n", __LINE__, VMCPU_FF_ISPENDING(pVCpuDst, VMCPU_FF_TIMER)));
347	VMCPU_FF_SET(pVCpuDst, VMCPU_FF_TIMER);
348	#ifdef IN_RING3
349	REMR3NotifyTimerPending(pVM, pVCpuDst);
350	VMR3NotifyCpuFFU(pVCpuDst->pUVCpu, VMNOTIFYFF_FLAGS_DONE_REM);
351	#endif
352	}
353	}
354	}
355	else
356	u64 = pVM->tm.s.u64Virtual;
357	return u64;
358	}
359
360
361	/**
362	* Gets the current TMCLOCK_VIRTUAL time
363	*
364	* @returns The timestamp.
365	* @param pVM VM handle.
366	*
367	* @remark While the flow of time will never go backwards, the speed of the
368	* progress varies due to inaccurate RTTimeNanoTS and TSC. The latter can be
369	* influenced by power saving (SpeedStep, PowerNow!), while the former
370	* makes use of TSC and kernel timers.
371	*/
372	VMM_INT_DECL(uint64_t) TMVirtualGet(PVM pVM)
373	{
374	return tmVirtualGet(pVM, true /* check timers */);
375	}
376
377
378	/**
379	* Gets the current TMCLOCK_VIRTUAL time without checking
380	* timers or anything.
381	*
382	* Meaning, this has no side effect on FFs like TMVirtualGet may have.
383	*
384	* @returns The timestamp.
385	* @param pVM VM handle.
386	*
387	* @remarks See TMVirtualGet.
388	*/
389	VMM_INT_DECL(uint64_t) TMVirtualGetNoCheck(PVM pVM)
390	{
391	return tmVirtualGet(pVM, false /fCheckTimers/);
392	}
393
394
395	/**
396	* tmVirtualSyncGetLocked worker for handling catch-up when owning the lock.
397	*
398	* @returns The timestamp.
399	* @param pVM VM handle.
400	* @param u64 raw virtual time.
401	* @param off offVirtualSync.
402	*/
403	DECLINLINE(uint64_t) tmVirtualSyncGetHandleCatchUpLocked(PVM pVM, uint64_t u64, uint64_t off)
404	{
405	STAM_COUNTER_INC(&pVM->tm.s.StatVirtualSyncGetLocked);
406
407	/*
408	* Don't make updates untill
409	*/
410	bool fUpdatePrev = true;
411	bool fUpdateOff = true;
412	bool fStop = false;
413	const uint64_t u64Prev = pVM->tm.s.u64VirtualSyncCatchUpPrev;
414	uint64_t u64Delta = u64 - u64Prev;
415	if (RT_LIKELY(!(u64Delta >> 32)))
416	{
417	uint64_t u64Sub = ASMMultU64ByU32DivByU32(u64Delta, pVM->tm.s.u32VirtualSyncCatchUpPercentage, 100);
418	if (off > u64Sub + pVM->tm.s.offVirtualSyncGivenUp)
419	{
420	off -= u64Sub;
421	Log4(("TM: %'RU64/-%'8RU64: sub %RU32 [vsghcul]\n", u64 - off, off - pVM->tm.s.offVirtualSyncGivenUp, u64Sub));
422	}
423	else
424	{
425	/* we've completely caught up. */
426	STAM_PROFILE_ADV_STOP(&pVM->tm.s.StatVirtualSyncCatchup, c);
427	off = pVM->tm.s.offVirtualSyncGivenUp;
428	fStop = true;
429	Log4(("TM: %'RU64/0: caught up [vsghcul]\n", u64));
430	}
431	}
432	else
433	{
434	/* More than 4 seconds since last time (or negative), ignore it. */
435	fUpdateOff = false;
436	fUpdatePrev = !(u64Delta & RT_BIT_64(63));
437	Log(("TMVirtualGetSync: u64Delta=%RX64\n", u64Delta));
438	}
439
440	/*
441	* Complete the calculation of the current TMCLOCK_VIRTUAL_SYNC time. The current
442	* approach is to never pass the head timer. So, when we do stop the clock and
443	* set the timer pending flag.
444	*/
445	u64 -= off;
446	uint64_t u64Expire = ASMAtomicReadU64(&pVM->tm.s.CTX_SUFF(paTimerQueues)[TMCLOCK_VIRTUAL_SYNC].u64Expire);
447	if (u64 < u64Expire)
448	{
449	if (fUpdateOff)
450	ASMAtomicWriteU64(&pVM->tm.s.offVirtualSync, off);
451	if (fStop)
452	ASMAtomicWriteBool(&pVM->tm.s.fVirtualSyncCatchUp, false);
453	if (fUpdatePrev)
454	ASMAtomicWriteU64(&pVM->tm.s.u64VirtualSyncCatchUpPrev, u64);
455	tmVirtualSyncUnlock(pVM);
456	}
457	else
458	{
459	u64 = u64Expire;
460	ASMAtomicWriteU64(&pVM->tm.s.u64VirtualSync, u64);
461	ASMAtomicWriteBool(&pVM->tm.s.fVirtualSyncTicking, false);
462
463	VM_FF_SET(pVM, VM_FF_TM_VIRTUAL_SYNC);
464	PVMCPU pVCpuDst = &pVM->aCpus[pVM->tm.s.idTimerCpu];
465	VMCPU_FF_SET(pVCpuDst, VMCPU_FF_TIMER);
466	Log5(("TMAllVirtual(%u): FF: %d -> 1\n", __LINE__, VMCPU_FF_ISPENDING(pVCpuDst, VMCPU_FF_TIMER)));
467	Log4(("TM: %'RU64/-%'8RU64: exp tmr=>ff [vsghcul]\n", u64, pVM->tm.s.offVirtualSync - pVM->tm.s.offVirtualSyncGivenUp));
468	tmVirtualSyncUnlock(pVM);
469
470	#ifdef IN_RING3
471	REMR3NotifyTimerPending(pVM, pVCpuDst);
472	VMR3NotifyCpuFFU(pVCpuDst->pUVCpu, VMNOTIFYFF_FLAGS_DONE_REM);
473	#endif
474	STAM_COUNTER_INC(&pVM->tm.s.StatVirtualSyncGetSetFF);
475	STAM_COUNTER_INC(&pVM->tm.s.StatVirtualSyncGetExpired);
476	}
477	STAM_COUNTER_INC(&pVM->tm.s.StatVirtualSyncGetLocked);
478
479	Log6(("tmVirtualSyncGetHandleCatchUpLocked -> %'RU64\n", u64));
480	return u64;
481	}
482
483
484	/**
485	* tmVirtualSyncGetEx worker for when we get the lock.
486	*
487	* @returns timesamp.
488	* @param pVM The VM handle.
489	* @param u64 The virtual clock timestamp.
490	*/
491	DECLINLINE(uint64_t) tmVirtualSyncGetLocked(PVM pVM, uint64_t u64)
492	{
493	/*
494	* Not ticking?
495	*/
496	if (!pVM->tm.s.fVirtualSyncTicking)
497	{
498	u64 = ASMAtomicUoReadU64(&pVM->tm.s.u64VirtualSync);
499	tmVirtualSyncUnlock(pVM);
500	STAM_COUNTER_INC(&pVM->tm.s.StatVirtualSyncGetLocked);
501	Log6(("tmVirtualSyncGetLocked -> %'RU64 [stopped]\n", u64));
502	return u64;
503	}
504
505	/*
506	* Handle catch up in a separate function.
507	*/
508	uint64_t off = ASMAtomicUoReadU64(&pVM->tm.s.offVirtualSync);
509	if (ASMAtomicUoReadBool(&pVM->tm.s.fVirtualSyncCatchUp))
510	return tmVirtualSyncGetHandleCatchUpLocked(pVM, u64, off);
511
512	/*
513	* Complete the calculation of the current TMCLOCK_VIRTUAL_SYNC time. The current
514	* approach is to never pass the head timer. So, when we do stop the clock and
515	* set the timer pending flag.
516	*/
517	u64 -= off;
518	uint64_t u64Expire = ASMAtomicReadU64(&pVM->tm.s.CTX_SUFF(paTimerQueues)[TMCLOCK_VIRTUAL_SYNC].u64Expire);
519	if (u64 < u64Expire)
520	tmVirtualSyncUnlock(pVM);
521	else
522	{
523	u64 = u64Expire;
524	ASMAtomicWriteU64(&pVM->tm.s.u64VirtualSync, u64);
525	ASMAtomicWriteBool(&pVM->tm.s.fVirtualSyncTicking, false);
526
527	VM_FF_SET(pVM, VM_FF_TM_VIRTUAL_SYNC);
528	PVMCPU pVCpuDst = &pVM->aCpus[pVM->tm.s.idTimerCpu];
529	VMCPU_FF_SET(pVCpuDst, VMCPU_FF_TIMER);
530	Log5(("TMAllVirtual(%u): FF: %d -> 1\n", __LINE__, !!VMCPU_FF_ISPENDING(pVCpuDst, VMCPU_FF_TIMER)));
531	Log4(("TM: %'RU64/-%'8RU64: exp tmr=>ff [vsgl]\n", u64, pVM->tm.s.offVirtualSync - pVM->tm.s.offVirtualSyncGivenUp));
532	tmVirtualSyncUnlock(pVM);
533
534	#ifdef IN_RING3
535	REMR3NotifyTimerPending(pVM, pVCpuDst);
536	VMR3NotifyCpuFFU(pVCpuDst->pUVCpu, VMNOTIFYFF_FLAGS_DONE_REM);
537	#endif
538	STAM_COUNTER_INC(&pVM->tm.s.StatVirtualSyncGetSetFF);
539	STAM_COUNTER_INC(&pVM->tm.s.StatVirtualSyncGetExpired);
540	}
541	STAM_COUNTER_INC(&pVM->tm.s.StatVirtualSyncGetLocked);
542	Log6(("tmVirtualSyncGetLocked -> %'RU64\n", u64));
543	return u64;
544	}
545
546
547	/**
548	* Gets the current TMCLOCK_VIRTUAL_SYNC time.
549	*
550	* @returns The timestamp.
551	* @param pVM VM handle.
552	* @param fCheckTimers Check timers or not
553	* @thread EMT.
554	*/
555	DECLINLINE(uint64_t) tmVirtualSyncGetEx(PVM pVM, bool fCheckTimers)
556	{
557	STAM_COUNTER_INC(&pVM->tm.s.StatVirtualSyncGet);
558
559	if (!pVM->tm.s.fVirtualSyncTicking)
560	return pVM->tm.s.u64VirtualSync;
561
562	/*
563	* Query the virtual clock and do the usual expired timer check.
564	*/
565	Assert(pVM->tm.s.cVirtualTicking);
566	uint64_t u64 = tmVirtualGetRaw(pVM);
567	if (fCheckTimers)
568	{
569	PVMCPU pVCpuDst = &pVM->aCpus[pVM->tm.s.idTimerCpu];
570	if ( !VMCPU_FF_ISSET(pVCpuDst, VMCPU_FF_TIMER)
571	&& pVM->tm.s.CTX_SUFF(paTimerQueues)[TMCLOCK_VIRTUAL].u64Expire <= u64)
572	{
573	Log5(("TMAllVirtual(%u): FF: 0 -> 1\n", __LINE__));
574	VMCPU_FF_SET(pVCpuDst, VMCPU_FF_TIMER);
575	#ifdef IN_RING3
576	REMR3NotifyTimerPending(pVM, pVCpuDst);
577	VMR3NotifyCpuFFU(pVCpuDst->pUVCpu, VMNOTIFYFF_FLAGS_DONE_REM /** @todo \|VMNOTIFYFF_FLAGS_POKE*/);
578	#endif
579	STAM_COUNTER_INC(&pVM->tm.s.StatVirtualSyncGetSetFF);
580	}
581	}
582
583	/*
584	* When the clock is ticking, not doing catch ups and not running into an
585	* expired time, we can get away without locking. Try this first.
586	*/
587	uint64_t off;
588	if (ASMAtomicUoReadBool(&pVM->tm.s.fVirtualSyncTicking))
589	{
590	if (!ASMAtomicUoReadBool(&pVM->tm.s.fVirtualSyncCatchUp))
591	{
592	off = ASMAtomicReadU64(&pVM->tm.s.offVirtualSync);
593	if (RT_LIKELY( ASMAtomicUoReadBool(&pVM->tm.s.fVirtualSyncTicking)
594	&& !ASMAtomicUoReadBool(&pVM->tm.s.fVirtualSyncCatchUp)
595	&& off == ASMAtomicReadU64(&pVM->tm.s.offVirtualSync)))
596	{
597	off = u64 - off;
598	if (off < ASMAtomicReadU64(&pVM->tm.s.CTX_SUFF(paTimerQueues)[TMCLOCK_VIRTUAL_SYNC].u64Expire))
599	{
600	STAM_COUNTER_INC(&pVM->tm.s.StatVirtualSyncGetLockless);
601	Log6(("tmVirtualSyncGetEx -> %'RU64 [lockless]\n", off));
602	return off;
603	}
604	}
605	}
606	}
607	else
608	{
609	off = ASMAtomicReadU64(&pVM->tm.s.u64VirtualSync);
610	if (RT_LIKELY(!ASMAtomicReadBool(&pVM->tm.s.fVirtualSyncTicking)))
611	{
612	STAM_COUNTER_INC(&pVM->tm.s.StatVirtualSyncGetLockless);
613	Log6(("tmVirtualSyncGetEx -> %'RU64 [lockless/stopped]\n", off));
614	return off;
615	}
616	}
617
618	/*
619	* Read the offset and adjust if we're playing catch-up.
620	*
621	* The catch-up adjusting work by us decrementing the offset by a percentage of
622	* the time elapsed since the previous TMVirtualGetSync call.
623	*
624	* It's possible to get a very long or even negative interval between two read
625	* for the following reasons:
626	* - Someone might have suspended the process execution, frequently the case when
627	* debugging the process.
628	* - We might be on a different CPU which TSC isn't quite in sync with the
629	* other CPUs in the system.
630	* - Another thread is racing us and we might have been preemnted while inside
631	* this function.
632	*
633	* Assuming nano second virtual time, we can simply ignore any intervals which has
634	* any of the upper 32 bits set.
635	*/
636	AssertCompile(TMCLOCK_FREQ_VIRTUAL == 1000000000);
637	int cOuterTries = 42;
638	for (;; cOuterTries--)
639	{
640	/* Try grab the lock, things get simpler when owning the lock. */
641	int rcLock = tmVirtualSyncTryLock(pVM);
642	if (RT_SUCCESS_NP(rcLock))
643	return tmVirtualSyncGetLocked(pVM, u64);
644
645	/* Re-check the ticking flag. */
646	if (!ASMAtomicReadBool(&pVM->tm.s.fVirtualSyncTicking))
647	{
648	off = ASMAtomicReadU64(&pVM->tm.s.u64VirtualSync);
649	if ( ASMAtomicReadBool(&pVM->tm.s.fVirtualSyncTicking)
650	&& cOuterTries > 0)
651	continue;
652	Log6(("tmVirtualSyncGetEx -> %'RU64 [stopped]\n", off));
653	return off;
654	}
655
656	off = ASMAtomicReadU64(&pVM->tm.s.offVirtualSync);
657	if (ASMAtomicReadBool(&pVM->tm.s.fVirtualSyncCatchUp))
658	{
659	/* No changes allowed, try get a consistent set of parameters. */
660	uint64_t const u64Prev = ASMAtomicReadU64(&pVM->tm.s.u64VirtualSyncCatchUpPrev);
661	uint64_t const offGivenUp = ASMAtomicReadU64(&pVM->tm.s.offVirtualSyncGivenUp);
662	uint32_t const u32Pct = ASMAtomicReadU32(&pVM->tm.s.u32VirtualSyncCatchUpPercentage);
663	if ( ( u64Prev == ASMAtomicReadU64(&pVM->tm.s.u64VirtualSyncCatchUpPrev)
664	&& offGivenUp == ASMAtomicReadU64(&pVM->tm.s.offVirtualSyncGivenUp)
665	&& u32Pct == ASMAtomicReadU32(&pVM->tm.s.u32VirtualSyncCatchUpPercentage)
666	&& ASMAtomicReadBool(&pVM->tm.s.fVirtualSyncCatchUp))
667	\|\| cOuterTries <= 0)
668	{
669	uint64_t u64Delta = u64 - u64Prev;
670	if (RT_LIKELY(!(u64Delta >> 32)))
671	{
672	uint64_t u64Sub = ASMMultU64ByU32DivByU32(u64Delta, u32Pct, 100);
673	if (off > u64Sub + offGivenUp)
674	{
675	off -= u64Sub;
676	Log4(("TM: %'RU64/-%'8RU64: sub %RU32 [NoLock]\n", u64 - off, pVM->tm.s.offVirtualSync - offGivenUp, u64Sub));
677	}
678	else
679	{
680	/* we've completely caught up. */
681	STAM_PROFILE_ADV_STOP(&pVM->tm.s.StatVirtualSyncCatchup, c);
682	off = offGivenUp;
683	Log4(("TM: %'RU64/0: caught up [NoLock]\n", u64));
684	}
685	}
686	else
687	/* More than 4 seconds since last time (or negative), ignore it. */
688	Log(("TMVirtualGetSync: u64Delta=%RX64 (NoLock)\n", u64Delta));
689
690	/* Check that we're still running and in catch up. */
691	if ( ASMAtomicUoReadBool(&pVM->tm.s.fVirtualSyncTicking)
692	&& ASMAtomicReadBool(&pVM->tm.s.fVirtualSyncCatchUp))
693	break;
694	if (cOuterTries <= 0)
695	break; /* enough */
696	}
697	}
698	else if ( off == ASMAtomicReadU64(&pVM->tm.s.offVirtualSync)
699	&& !ASMAtomicReadBool(&pVM->tm.s.fVirtualSyncCatchUp))
700	break; /* Got an consistent offset */
701	else if (cOuterTries <= 0)
702	break; /* enough */
703	}
704	if (cOuterTries <= 0)
705	STAM_COUNTER_INC(&pVM->tm.s.StatVirtualSyncGetELoop);
706
707	/*
708	* Complete the calculation of the current TMCLOCK_VIRTUAL_SYNC time. The current
709	* approach is to never pass the head timer. So, when we do stop the clock and
710	* set the timer pending flag.
711	*/
712	u64 -= off;
713	uint64_t u64Expire = ASMAtomicReadU64(&pVM->tm.s.CTX_SUFF(paTimerQueues)[TMCLOCK_VIRTUAL_SYNC].u64Expire);
714	if (u64 >= u64Expire)
715	{
716	PVMCPU pVCpuDst = &pVM->aCpus[pVM->tm.s.idTimerCpu];
717	if (!VMCPU_FF_ISSET(pVCpuDst, VMCPU_FF_TIMER))
718	{
719	Log5(("TMAllVirtual(%u): FF: %d -> 1 (NoLock)\n", __LINE__, VMCPU_FF_ISPENDING(pVCpuDst, VMCPU_FF_TIMER)));
720	VM_FF_SET(pVM, VM_FF_TM_VIRTUAL_SYNC); /* Hmm? */
721	VMCPU_FF_SET(pVCpuDst, VMCPU_FF_TIMER);
722	#ifdef IN_RING3
723	REMR3NotifyTimerPending(pVM, pVCpuDst);
724	VMR3NotifyCpuFFU(pVCpuDst->pUVCpu, VMNOTIFYFF_FLAGS_DONE_REM);
725	#endif
726	STAM_COUNTER_INC(&pVM->tm.s.StatVirtualSyncGetSetFF);
727	Log4(("TM: %'RU64/-%'8RU64: exp tmr=>ff [NoLock]\n", u64, pVM->tm.s.offVirtualSync - pVM->tm.s.offVirtualSyncGivenUp));
728	}
729	else
730	Log4(("TM: %'RU64/-%'8RU64: exp tmr [NoLock]\n", u64, pVM->tm.s.offVirtualSync - pVM->tm.s.offVirtualSyncGivenUp));
731	STAM_COUNTER_INC(&pVM->tm.s.StatVirtualSyncGetExpired);
732	}
733
734	Log6(("tmVirtualSyncGetEx -> %'RU64\n", u64));
735	return u64;
736	}
737
738
739	/**
740	* Gets the current TMCLOCK_VIRTUAL_SYNC time.
741	*
742	* @returns The timestamp.
743	* @param pVM VM handle.
744	* @thread EMT.
745	* @remarks May set the timer and virtual sync FFs.
746	*/
747	VMM_INT_DECL(uint64_t) TMVirtualSyncGet(PVM pVM)
748	{
749	return tmVirtualSyncGetEx(pVM, true /* check timers */);
750	}
751
752
753	/**
754	* Gets the current TMCLOCK_VIRTUAL_SYNC time without checking timers running on
755	* TMCLOCK_VIRTUAL.
756	*
757	* @returns The timestamp.
758	* @param pVM VM handle.
759	* @thread EMT.
760	* @remarks May set the timer and virtual sync FFs.
761	*/
762	VMM_INT_DECL(uint64_t) TMVirtualSyncGetNoCheck(PVM pVM)
763	{
764	return tmVirtualSyncGetEx(pVM, false /* check timers */);
765	}
766
767
768	/**
769	* Gets the current TMCLOCK_VIRTUAL_SYNC time.
770	*
771	* @returns The timestamp.
772	* @param pVM VM handle.
773	* @param fCheckTimers Check timers on the virtual clock or not.
774	* @thread EMT.
775	* @remarks May set the timer and virtual sync FFs.
776	*/
777	VMM_INT_DECL(uint64_t) TMVirtualSyncGetEx(PVM pVM, bool fCheckTimers)
778	{
779	return tmVirtualSyncGetEx(pVM, fCheckTimers);
780	}
781
782
783	/**
784	* Gets the current lag of the synchronous virtual clock (relative to the virtual clock).
785	*
786	* @return The current lag.
787	* @param pVM VM handle.
788	*/
789	VMM_INT_DECL(uint64_t) TMVirtualSyncGetLag(PVM pVM)
790	{
791	return pVM->tm.s.offVirtualSync - pVM->tm.s.offVirtualSyncGivenUp;
792	}
793
794
795	/**
796	* Get the current catch-up percent.
797	*
798	* @return The current catch0up percent. 0 means running at the same speed as the virtual clock.
799	* @param pVM VM handle.
800	*/
801	VMM_INT_DECL(uint32_t) TMVirtualSyncGetCatchUpPct(PVM pVM)
802	{
803	if (pVM->tm.s.fVirtualSyncCatchUp)
804	return pVM->tm.s.u32VirtualSyncCatchUpPercentage;
805	return 0;
806	}
807
808
809	/**
810	* Gets the current TMCLOCK_VIRTUAL frequency.
811	*
812	* @returns The freqency.
813	* @param pVM VM handle.
814	*/
815	VMM_INT_DECL(uint64_t) TMVirtualGetFreq(PVM pVM)
816	{
817	return TMCLOCK_FREQ_VIRTUAL;
818	}
819
820
821	/**
822	* Worker for TMR3PauseClocks.
823	*
824	* @returns VINF_SUCCESS or VERR_INTERNAL_ERROR (asserted).
825	* @param pVM The VM handle.
826	*/
827	int tmVirtualPauseLocked(PVM pVM)
828	{
829	uint32_t c = ASMAtomicDecU32(&pVM->tm.s.cVirtualTicking);
830	AssertMsgReturn(c < pVM->cCpus, ("%u vs %u\n", c, pVM->cCpus), VERR_INTERNAL_ERROR);
831	if (c == 0)
832	{
833	STAM_COUNTER_INC(&pVM->tm.s.StatVirtualPause);
834	pVM->tm.s.u64Virtual = tmVirtualGetRaw(pVM);
835	ASMAtomicWriteBool(&pVM->tm.s.fVirtualSyncTicking, false);
836	}
837	return VINF_SUCCESS;
838	}
839
840
841	/**
842	* Worker for TMR3ResumeClocks.
843	*
844	* @returns VINF_SUCCESS or VERR_INTERNAL_ERROR (asserted).
845	* @param pVM The VM handle.
846	*/
847	int tmVirtualResumeLocked(PVM pVM)
848	{
849	uint32_t c = ASMAtomicIncU32(&pVM->tm.s.cVirtualTicking);
850	AssertMsgReturn(c <= pVM->cCpus, ("%u vs %u\n", c, pVM->cCpus), VERR_INTERNAL_ERROR);
851	if (c == 1)
852	{
853	STAM_COUNTER_INC(&pVM->tm.s.StatVirtualResume);
854	pVM->tm.s.u64VirtualRawPrev = 0;
855	pVM->tm.s.u64VirtualWarpDriveStart = tmVirtualGetRawNanoTS(pVM);
856	pVM->tm.s.u64VirtualOffset = pVM->tm.s.u64VirtualWarpDriveStart - pVM->tm.s.u64Virtual;
857	ASMAtomicWriteBool(&pVM->tm.s.fVirtualSyncTicking, true);
858	}
859	return VINF_SUCCESS;
860	}
861
862
863	/**
864	* Converts from virtual ticks to nanoseconds.
865	*
866	* @returns nanoseconds.
867	* @param pVM The VM handle.
868	* @param u64VirtualTicks The virtual ticks to convert.
869	* @remark There could be rounding errors here. We just do a simple integere divide
870	* without any adjustments.
871	*/
872	VMM_INT_DECL(uint64_t) TMVirtualToNano(PVM pVM, uint64_t u64VirtualTicks)
873	{
874	AssertCompile(TMCLOCK_FREQ_VIRTUAL == 1000000000);
875	return u64VirtualTicks;
876	}
877
878
879	/**
880	* Converts from virtual ticks to microseconds.
881	*
882	* @returns microseconds.
883	* @param pVM The VM handle.
884	* @param u64VirtualTicks The virtual ticks to convert.
885	* @remark There could be rounding errors here. We just do a simple integere divide
886	* without any adjustments.
887	*/
888	VMM_INT_DECL(uint64_t) TMVirtualToMicro(PVM pVM, uint64_t u64VirtualTicks)
889	{
890	AssertCompile(TMCLOCK_FREQ_VIRTUAL == 1000000000);
891	return u64VirtualTicks / 1000;
892	}
893
894
895	/**
896	* Converts from virtual ticks to milliseconds.
897	*
898	* @returns milliseconds.
899	* @param pVM The VM handle.
900	* @param u64VirtualTicks The virtual ticks to convert.
901	* @remark There could be rounding errors here. We just do a simple integere divide
902	* without any adjustments.
903	*/
904	VMM_INT_DECL(uint64_t) TMVirtualToMilli(PVM pVM, uint64_t u64VirtualTicks)
905	{
906	AssertCompile(TMCLOCK_FREQ_VIRTUAL == 1000000000);
907	return u64VirtualTicks / 1000000;
908	}
909
910
911	/**
912	* Converts from nanoseconds to virtual ticks.
913	*
914	* @returns virtual ticks.
915	* @param pVM The VM handle.
916	* @param u64NanoTS The nanosecond value ticks to convert.
917	* @remark There could be rounding and overflow errors here.
918	*/
919	VMM_INT_DECL(uint64_t) TMVirtualFromNano(PVM pVM, uint64_t u64NanoTS)
920	{
921	AssertCompile(TMCLOCK_FREQ_VIRTUAL == 1000000000);
922	return u64NanoTS;
923	}
924
925
926	/**
927	* Converts from microseconds to virtual ticks.
928	*
929	* @returns virtual ticks.
930	* @param pVM The VM handle.
931	* @param u64MicroTS The microsecond value ticks to convert.
932	* @remark There could be rounding and overflow errors here.
933	*/
934	VMM_INT_DECL(uint64_t) TMVirtualFromMicro(PVM pVM, uint64_t u64MicroTS)
935	{
936	AssertCompile(TMCLOCK_FREQ_VIRTUAL == 1000000000);
937	return u64MicroTS * 1000;
938	}
939
940
941	/**
942	* Converts from milliseconds to virtual ticks.
943	*
944	* @returns virtual ticks.
945	* @param pVM The VM handle.
946	* @param u64MilliTS The millisecond value ticks to convert.
947	* @remark There could be rounding and overflow errors here.
948	*/
949	VMM_INT_DECL(uint64_t) TMVirtualFromMilli(PVM pVM, uint64_t u64MilliTS)
950	{
951	AssertCompile(TMCLOCK_FREQ_VIRTUAL == 1000000000);
952	return u64MilliTS * 1000000;
953	}
954

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source: vbox/trunk/src/VBox/VMM/VMMAll/TMAllVirtual.cpp@ 23794

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