tstTSC.cpp@ 35761

Last change on this file since 35761 was 33540, checked in by vboxsync, 14 years ago
*: spelling fixes, thanks Timeless!
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1	/* $Id: tstTSC.cpp 33540 2010-10-28 09:27:05Z vboxsync $ */
2	/** @file
3	* IPRT Testcase - SMP TSC testcase.
4	*/
5
6	/*
7	* Copyright (C) 2006-2007 Oracle Corporation
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
27	/*******************************************************************************
28	* Header Files *
29	*******************************************************************************/
30	#include <iprt/asm-amd64-x86.h>
31	#include <iprt/asm.h>
32	#include <iprt/getopt.h>
33	#include <iprt/initterm.h>
34	#include <iprt/mp.h>
35	#include <iprt/stream.h>
36	#include <iprt/string.h>
37	#include <iprt/thread.h>
38	#include <iprt/time.h>
39
40
41	/*******************************************************************************
42	* Structures and Typedefs *
43	*******************************************************************************/
44	typedef struct TSCDATA
45	{
46	/** The TSC. */
47	uint64_t volatile TSC;
48	/** The APIC ID. */
49	uint8_t volatile u8ApicId;
50	/** Did it succeed? */
51	bool volatile fRead;
52	/** Did it fail? */
53	bool volatile fFailed;
54	/** The thread handle. */
55	RTTHREAD Thread;
56	} TSCDATA, *PTSCDATA;
57
58
59	/*******************************************************************************
60	* Global Variables *
61	*******************************************************************************/
62	/** The number of CPUs waiting on their user event semaphore. */
63	static volatile uint32_t g_cWaiting;
64	/** The number of CPUs ready (in spin) to do the TSC read. */
65	static volatile uint32_t g_cReady;
66	/** The variable the CPUs are spinning on.
67	* 0: Spin.
68	* 1: Go ahead.
69	* 2: You're too late, back to square one. */
70	static volatile uint32_t g_u32Go;
71	/** The number of CPUs that managed to read the TSC. */
72	static volatile uint32_t g_cRead;
73	/** The number of CPUs that failed to read the TSC. */
74	static volatile uint32_t g_cFailed;
75
76	/** Indicator forcing the threads to quit. */
77	static volatile bool g_fDone;
78
79
80	/*******************************************************************************
81	* Internal Functions *
82	*******************************************************************************/
83	static DECLCALLBACK(int) ThreadFunction(RTTHREAD Thread, void *pvUser);
84
85
86	/**
87	* Thread function for catching the other cpus.
88	*
89	* @returns VINF_SUCCESS (we don't care).
90	* @param Thread The thread handle.
91	* @param pvUser PTSCDATA.
92	*/
93	static DECLCALLBACK(int) ThreadFunction(RTTHREAD Thread, void *pvUser)
94	{
95	PTSCDATA pTscData = (PTSCDATA)pvUser;
96
97	while (!g_fDone)
98	{
99	/*
100	* Wait.
101	*/
102	ASMAtomicIncU32(&g_cWaiting);
103	RTThreadUserWait(Thread, RT_INDEFINITE_WAIT);
104	RTThreadUserReset(Thread);
105	ASMAtomicDecU32(&g_cWaiting);
106	if (g_fDone)
107	break;
108
109	/*
110	* Spin.
111	*/
112	ASMAtomicIncU32(&g_cReady);
113	while (!g_fDone)
114	{
115	const uint8_t ApicId1 = ASMGetApicId();
116	const uint64_t TSC1 = ASMReadTSC();
117	const uint32_t u32Go = g_u32Go;
118	if (u32Go == 0)
119	continue;
120
121	if (u32Go == 1)
122	{
123	/* do the reading. */
124	const uint8_t ApicId2 = ASMGetApicId();
125	const uint64_t TSC2 = ASMReadTSC();
126	const uint8_t ApicId3 = ASMGetApicId();
127	const uint64_t TSC3 = ASMReadTSC();
128	const uint8_t ApicId4 = ASMGetApicId();
129
130	if ( ApicId1 == ApicId2
131	&& ApicId1 == ApicId3
132	&& ApicId1 == ApicId4
133	&& TSC3 - TSC1 < 2250 /* WARNING: This is just a guess, increase if it doesn't work for you. */
134	&& TSC2 - TSC1 < TSC3 - TSC1
135	)
136	{
137	/* succeeded. */
138	pTscData->TSC = TSC2;
139	pTscData->u8ApicId = ApicId1;
140	pTscData->fFailed = false;
141	pTscData->fRead = true;
142	ASMAtomicIncU32(&g_cRead);
143	break;
144	}
145	}
146
147	/* failed */
148	pTscData->fFailed = true;
149	pTscData->fRead = false;
150	ASMAtomicIncU32(&g_cFailed);
151	break;
152	}
153	}
154
155	return VINF_SUCCESS;
156	}
157
158	static int tstTSCCalcDrift(void)
159	{
160	/*
161	* This is only relevant to on SMP systems.
162	*/
163	const unsigned cCpus = RTMpGetOnlineCount();
164	if (cCpus <= 1)
165	{
166	RTPrintf("tstTSC: SKIPPED - Only relevant on SMP systems\n");
167	return 0;
168	}
169
170	/*
171	* Create the threads.
172	*/
173	static TSCDATA s_aData[254];
174	uint32_t i;
175	if (cCpus > RT_ELEMENTS(s_aData))
176	{
177	RTPrintf("tstTSC: FAILED - too many CPUs (%u)\n", cCpus);
178	return 1;
179	}
180
181	/* ourselves. */
182	s_aData[0].Thread = RTThreadSelf();
183
184	/* the others */
185	for (i = 1; i < cCpus; i++)
186	{
187	int rc = RTThreadCreate(&s_aData[i].Thread, ThreadFunction, &s_aData[i], 0, RTTHREADTYPE_TIMER, RTTHREADFLAGS_WAITABLE, "OTHERCPU");
188	if (RT_FAILURE(rc))
189	{
190	RTPrintf("tstTSC: FAILURE - RTThreatCreate failed when creating thread #%u, rc=%Rrc!\n", i, rc);
191	ASMAtomicXchgSize(&g_fDone, true);
192	while (i-- > 1)
193	{
194	RTThreadUserSignal(s_aData[i].Thread);
195	RTThreadWait(s_aData[i].Thread, 5000, NULL);
196	}
197	return 1;
198	}
199	}
200
201	/*
202	* Retry until we get lucky (or give up).
203	*/
204	for (unsigned cTries = 0; ; cTries++)
205	{
206	if (cTries > 10240)
207	{
208	RTPrintf("tstTSC: FAILURE - %d attempts, giving.\n", cTries);
209	break;
210	}
211
212	/*
213	* Wait for the other threads to get ready (brute force active wait, I'm lazy).
214	*/
215	i = 0;
216	while (g_cWaiting < cCpus - 1)
217	{
218	if (i++ > _2G32)
219	break;
220	RTThreadSleep(i & 0xf);
221	}
222	if (g_cWaiting != cCpus - 1)
223	{
224	RTPrintf("tstTSC: FAILURE - threads failed to get waiting (%d != %d (i=%d))\n", g_cWaiting + 1, cCpus, i);
225	break;
226	}
227
228	/*
229	* Send them spinning.
230	*/
231	ASMAtomicXchgU32(&g_cReady, 0);
232	ASMAtomicXchgU32(&g_u32Go, 0);
233	ASMAtomicXchgU32(&g_cRead, 0);
234	ASMAtomicXchgU32(&g_cFailed, 0);
235	for (i = 1; i < cCpus; i++)
236	{
237	ASMAtomicXchgSize(&s_aData[i].fFailed, false);
238	ASMAtomicXchgSize(&s_aData[i].fRead, false);
239	ASMAtomicXchgU8(&s_aData[i].u8ApicId, 0xff);
240
241	int rc = RTThreadUserSignal(s_aData[i].Thread);
242	if (RT_FAILURE(rc))
243	RTPrintf("tstTSC: WARNING - RTThreadUserSignal(%#u) -> rc=%Rrc!\n", i, rc);
244	}
245
246	/* wait for them to get ready. */
247	i = 0;
248	while (g_cReady < cCpus - 1)
249	{
250	if (i++ > _2G32)
251	break;
252	}
253	if (g_cReady != cCpus - 1)
254	{
255	RTPrintf("tstTSC: FAILURE - threads failed to get ready (%d != %d, i=%d)\n", g_cWaiting + 1, cCpus, i);
256	break;
257	}
258
259	/*
260	* Flip the "go" switch and do our readings.
261	* We give the other threads the slack it takes to two extra TSC and APIC ID reads.
262	*/
263	const uint8_t ApicId1 = ASMGetApicId();
264	const uint64_t TSC1 = ASMReadTSC();
265	ASMAtomicXchgU32(&g_u32Go, 1);
266	const uint8_t ApicId2 = ASMGetApicId();
267	const uint64_t TSC2 = ASMReadTSC();
268	const uint8_t ApicId3 = ASMGetApicId();
269	const uint64_t TSC3 = ASMReadTSC();
270	const uint8_t ApicId4 = ASMGetApicId();
271	const uint64_t TSC4 = ASMReadTSC();
272	ASMAtomicXchgU32(&g_u32Go, 2);
273	const uint8_t ApicId5 = ASMGetApicId();
274	const uint64_t TSC5 = ASMReadTSC();
275	const uint8_t ApicId6 = ASMGetApicId();
276
277	/* Compose our own result. */
278	if ( ApicId1 == ApicId2
279	&& ApicId1 == ApicId3
280	&& ApicId1 == ApicId4
281	&& ApicId1 == ApicId5
282	&& ApicId1 == ApicId6
283	&& TSC5 - TSC1 < 2750 /* WARNING: This is just a guess, increase if it doesn't work for you. */
284	&& TSC4 - TSC1 < TSC5 - TSC1
285	&& TSC3 - TSC1 < TSC4 - TSC1
286	&& TSC2 - TSC1 < TSC3 - TSC1
287	)
288	{
289	/* succeeded. */
290	s_aData[0].TSC = TSC2;
291	s_aData[0].u8ApicId = ApicId1;
292	s_aData[0].fFailed = false;
293	s_aData[0].fRead = true;
294	ASMAtomicIncU32(&g_cRead);
295	}
296	else
297	{
298	/* failed */
299	s_aData[0].fFailed = true;
300	s_aData[0].fRead = false;
301	ASMAtomicIncU32(&g_cFailed);
302	}
303
304	/*
305	* Wait a little while to let the other ones to finish.
306	*/
307	i = 0;
308	while (g_cRead + g_cFailed < cCpus)
309	{
310	if (i++ > _2G32)
311	break;
312	if (i > _1M)
313	RTThreadSleep(i & 0xf);
314	}
315	if (g_cRead + g_cFailed != cCpus)
316	{
317	RTPrintf("tstTSC: FAILURE - threads failed to complete reading (%d + %d != %d)\n", g_cRead, g_cFailed, cCpus);
318	break;
319	}
320
321	/*
322	* If everone succeeded, print the results.
323	*/
324	if (!g_cFailed)
325	{
326	/* sort it by apic id first. */
327	bool fDone;
328	do
329	{
330	for (i = 1, fDone = true; i < cCpus; i++)
331	if (s_aData[i - 1].u8ApicId > s_aData[i].u8ApicId)
332	{
333	TSCDATA Tmp = s_aData[i - 1];
334	s_aData[i - 1] = s_aData[i];
335	s_aData[i] = Tmp;
336	fDone = false;
337	}
338	} while (!fDone);
339
340	RTPrintf(" # ID TSC delta0 (decimal)\n"
341	"-----------------------------------------\n");
342	RTPrintf("%2d %02x %RX64\n", 0, s_aData[0].u8ApicId, s_aData[0].TSC);
343	for (i = 1; i < cCpus; i++)
344	RTPrintf("%2d %02x %RX64 %s%lld\n", i, s_aData[i].u8ApicId, s_aData[i].TSC,
345	s_aData[i].TSC > s_aData[0].TSC ? "+" : "", s_aData[i].TSC - s_aData[0].TSC);
346	RTPrintf("(Needed %u attempt%s.)\n", cTries + 1, cTries ? "s" : "");
347	break;
348	}
349	}
350
351	/*
352	* Destroy the threads.
353	*/
354	ASMAtomicXchgSize(&g_fDone, true);
355	for (i = 0; i < cCpus; i++)
356	if (s_aData[i].Thread != RTThreadSelf())
357	{
358	int rc = RTThreadUserSignal(s_aData[i].Thread);
359	if (RT_FAILURE(rc))
360	RTPrintf("tstTSC: WARNING - RTThreadUserSignal(%#u) -> rc=%Rrc! (2)\n", i, rc);
361	}
362	for (i = 0; i < cCpus; i++)
363	if (s_aData[i].Thread != RTThreadSelf())
364	{
365	int rc = RTThreadWait(s_aData[i].Thread, 5000, NULL);
366	if (RT_FAILURE(rc))
367	RTPrintf("tstTSC: WARNING - RTThreadWait(%#u) -> rc=%Rrc!\n", i, rc);
368	}
369
370	return g_cFailed != 0 \|\| g_cRead != cCpus;
371	}
372
373
374	static int tstTSCCalcFrequency(uint32_t cMsDuration)
375	{
376	/*
377	* Sample the TSC and time, sleep the requested time and calc the deltas.
378	*/
379	uint64_t uNanoTS = RTTimeSystemNanoTS();
380	uint64_t uTSC = ASMReadTSC();
381	RTThreadSleep(cMsDuration);
382	uNanoTS = RTTimeSystemNanoTS() - uNanoTS;
383	uTSC = ASMReadTSC() - uTSC;
384
385	/*
386	* Calc the frequency.
387	*/
388	RTPrintf("tstTSC: %RU64 ticks in %RU64 ns\n", uTSC, uNanoTS);
389	uint64_t cHz = (uint64_t)(uTSC / ((long double)uNanoTS / (long double)1000000000));
390	RTPrintf("tstTSC: Frequency %RU64 Hz", cHz);
391	if (cHz > _1G)
392	{
393	cHz += _1G / 20;
394	RTPrintf(" %RU64.%RU64 GHz", cHz / _1G, (cHz % _1G) / (_1G / 10));
395	}
396	else if (cHz > _1M)
397	{
398	cHz += _1M / 20;
399	RTPrintf(" %RU64.%RU64 MHz", cHz / _1M, (cHz % _1M) / (_1M / 10));
400	}
401	RTPrintf("\n");
402	return 0;
403	}
404
405
406	int main(int argc, char **argv)
407	{
408	RTR3Init();
409
410	/*
411	* Parse arguments.
412	*/
413	bool fCalcFrequency = false;
414	uint32_t cMsDuration = 1000; /* 1 sec */
415	static const RTGETOPTDEF s_aOptions[] =
416	{
417	{ "--duration", 'd', RTGETOPT_REQ_UINT32 },
418	{ "--calc-frequency", 'f', RTGETOPT_REQ_NOTHING },
419	};
420	int iArg = 1;
421	int ch;
422	RTGETOPTUNION Value;
423	RTGETOPTSTATE GetState;
424	RTGetOptInit(&GetState, argc, argv, s_aOptions, RT_ELEMENTS(s_aOptions), 1, 0 /* fFlags */);
425	while ((ch = RTGetOpt(&GetState, &Value)))
426	switch (ch)
427	{
428	case 'd': cMsDuration = Value.u32;
429	break;
430
431	case 'f': fCalcFrequency = true;
432	break;
433
434	case 'h':
435	RTPrintf("usage: tstTSC\n"
436	" or: tstTSC <-f\|--calc-frequency> [--duration\|-d ms]\n");
437	return 1;
438
439	case 'V':
440	RTPrintf("$Revision: $\n");
441	return 0;
442
443	default:
444	return RTGetOptPrintError(ch, &Value);
445	}
446
447	if (fCalcFrequency)
448	return tstTSCCalcFrequency(cMsDuration);
449	return tstTSCCalcDrift();
450	}
451

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source: vbox/trunk/src/VBox/Runtime/testcase/tstTSC.cpp@ 35761

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