tstTSC.cpp@ 16684

Last change on this file since 16684 was 12548, checked in by vboxsync, 16 years ago
iprt/tstTSC: Extended it with an option (-f) for sampling the frequency instead of calcing the TSC drift.
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1	/* $Id: tstTSC.cpp 12548 2008-09-17 17:59:49Z vboxsync $ */
2	/** @file
3	* IPRT Testcase - SMP TSC testcase.
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	* Header Files *
33	*******************************************************************************/
34	#include <iprt/asm.h>
35	#include <iprt/getopt.h>
36	#include <iprt/initterm.h>
37	#include <iprt/mp.h>
38	#include <iprt/stream.h>
39	#include <iprt/string.h>
40	#include <iprt/thread.h>
41	#include <iprt/time.h>
42
43
44	/*******************************************************************************
45	* Structures and Typedefs *
46	*******************************************************************************/
47	typedef struct TSCDATA
48	{
49	/** The TSC. */
50	uint64_t volatile TSC;
51	/** The APIC ID. */
52	uint8_t volatile u8ApicId;
53	/** Did it succeed? */
54	bool volatile fRead;
55	/** Did it fail? */
56	bool volatile fFailed;
57	/** The thread handle. */
58	RTTHREAD Thread;
59	} TSCDATA, *PTSCDATA;
60
61
62	/*******************************************************************************
63	* Global Variables *
64	*******************************************************************************/
65	/** The number of CPUs waiting on their user event semaphore. */
66	static volatile uint32_t g_cWaiting;
67	/** The number of CPUs ready (in spin) to do the TSC read. */
68	static volatile uint32_t g_cReady;
69	/** The variable the CPUs are spinning on.
70	* 0: Spin.
71	* 1: Go ahead.
72	* 2: You're too late, back to square one. */
73	static volatile uint32_t g_u32Go;
74	/** The number of CPUs that managed to read the TSC. */
75	static volatile uint32_t g_cRead;
76	/** The number of CPUs that failed to read the TSC. */
77	static volatile uint32_t g_cFailed;
78
79	/** Indicator forcing the threads to quit. */
80	static volatile bool g_fDone;
81
82
83	/*******************************************************************************
84	* Internal Functions *
85	*******************************************************************************/
86	static DECLCALLBACK(int) ThreadFunction(RTTHREAD Thread, void *pvUser);
87
88
89	/**
90	* Thread function for catching the other cpus.
91	*
92	* @returns VINF_SUCCESS (we don't care).
93	* @param Thread The thread handle.
94	* @param pvUser PTSCDATA.
95	*/
96	static DECLCALLBACK(int) ThreadFunction(RTTHREAD Thread, void *pvUser)
97	{
98	PTSCDATA pTscData = (PTSCDATA)pvUser;
99
100	while (!g_fDone)
101	{
102	/*
103	* Wait.
104	*/
105	ASMAtomicIncU32(&g_cWaiting);
106	RTThreadUserWait(Thread, RT_INDEFINITE_WAIT);
107	RTThreadUserReset(Thread);
108	ASMAtomicDecU32(&g_cWaiting);
109	if (g_fDone)
110	break;
111
112	/*
113	* Spin.
114	*/
115	ASMAtomicIncU32(&g_cReady);
116	while (!g_fDone)
117	{
118	const uint8_t ApicId1 = ASMGetApicId();
119	const uint64_t TSC1 = ASMReadTSC();
120	const uint32_t u32Go = g_u32Go;
121	if (u32Go == 0)
122	continue;
123
124	if (u32Go == 1)
125	{
126	/* do the reading. */
127	const uint8_t ApicId2 = ASMGetApicId();
128	const uint64_t TSC2 = ASMReadTSC();
129	const uint8_t ApicId3 = ASMGetApicId();
130	const uint64_t TSC3 = ASMReadTSC();
131	const uint8_t ApicId4 = ASMGetApicId();
132
133	if ( ApicId1 == ApicId2
134	&& ApicId1 == ApicId3
135	&& ApicId1 == ApicId4
136	&& TSC3 - TSC1 < 2250 /* WARNING: This is just a guess, increase if it doesn't work for you. */
137	&& TSC2 - TSC1 < TSC3 - TSC1
138	)
139	{
140	/* succeeded. */
141	pTscData->TSC = TSC2;
142	pTscData->u8ApicId = ApicId1;
143	pTscData->fFailed = false;
144	pTscData->fRead = true;
145	ASMAtomicIncU32(&g_cRead);
146	break;
147	}
148	}
149
150	/* failed */
151	pTscData->fFailed = true;
152	pTscData->fRead = false;
153	ASMAtomicIncU32(&g_cFailed);
154	break;
155	}
156	}
157
158	return VINF_SUCCESS;
159	}
160
161	static int tstTSCCalcDrift(void)
162	{
163	/*
164	* This is only relevant to on SMP systems.
165	*/
166	const unsigned cCpus = RTMpGetOnlineCount();
167	if (cCpus <= 1)
168	{
169	RTPrintf("tstTSC: SKIPPED - Only relevant on SMP systems\n");
170	return 0;
171	}
172
173	/*
174	* Create the threads.
175	*/
176	static TSCDATA s_aData[254];
177	uint32_t i;
178	if (cCpus > RT_ELEMENTS(s_aData))
179	{
180	RTPrintf("tstTSC: FAILED - too many CPUs (%u)\n", cCpus);
181	return 1;
182	}
183
184	/* ourselves. */
185	s_aData[0].Thread = RTThreadSelf();
186
187	/* the others */
188	for (i = 1; i < cCpus; i++)
189	{
190	int rc = RTThreadCreate(&s_aData[i].Thread, ThreadFunction, &s_aData[i], 0, RTTHREADTYPE_TIMER, RTTHREADFLAGS_WAITABLE, "OTHERCPU");
191	if (RT_FAILURE(rc))
192	{
193	RTPrintf("tstTSC: FAILURE - RTThreatCreate failed when creating thread #%u, rc=%Rrc!\n", i, rc);
194	ASMAtomicXchgSize(&g_fDone, true);
195	while (i-- > 1)
196	{
197	RTThreadUserSignal(s_aData[i].Thread);
198	RTThreadWait(s_aData[i].Thread, 5000, NULL);
199	}
200	return 1;
201	}
202	}
203
204	/*
205	* Retry untill we get lucky (or give up).
206	*/
207	for (unsigned cTries = 0; ; cTries++)
208	{
209	if (cTries > 10240)
210	{
211	RTPrintf("tstTSC: FAILURE - %d attempts, giving.\n", cTries);
212	break;
213	}
214
215	/*
216	* Wait for the other threads to get ready (brute force active wait, I'm lazy).
217	*/
218	i = 0;
219	while (g_cWaiting < cCpus - 1)
220	{
221	if (i++ > _2G32)
222	break;
223	RTThreadSleep(i & 0xf);
224	}
225	if (g_cWaiting != cCpus - 1)
226	{
227	RTPrintf("tstTSC: FAILURE - threads failed to get waiting (%d != %d (i=%d))\n", g_cWaiting + 1, cCpus, i);
228	break;
229	}
230
231	/*
232	* Send them spinning.
233	*/
234	ASMAtomicXchgU32(&g_cReady, 0);
235	ASMAtomicXchgU32(&g_u32Go, 0);
236	ASMAtomicXchgU32(&g_cRead, 0);
237	ASMAtomicXchgU32(&g_cFailed, 0);
238	for (i = 1; i < cCpus; i++)
239	{
240	ASMAtomicXchgSize(&s_aData[i].fFailed, false);
241	ASMAtomicXchgSize(&s_aData[i].fRead, false);
242	ASMAtomicXchgU8(&s_aData[i].u8ApicId, 0xff);
243
244	int rc = RTThreadUserSignal(s_aData[i].Thread);
245	if (RT_FAILURE(rc))
246	RTPrintf("tstTSC: WARNING - RTThreadUserSignal(%#u) -> rc=%Rrc!\n", i, rc);
247	}
248
249	/* wait for them to get ready. */
250	i = 0;
251	while (g_cReady < cCpus - 1)
252	{
253	if (i++ > _2G32)
254	break;
255	}
256	if (g_cReady != cCpus - 1)
257	{
258	RTPrintf("tstTSC: FAILURE - threads failed to get ready (%d != %d, i=%d)\n", g_cWaiting + 1, cCpus, i);
259	break;
260	}
261
262	/*
263	* Flip the "go" switch and do our readings.
264	* We give the other threads the slack it takes to two extra TSC and APIC ID reads.
265	*/
266	const uint8_t ApicId1 = ASMGetApicId();
267	const uint64_t TSC1 = ASMReadTSC();
268	ASMAtomicXchgU32(&g_u32Go, 1);
269	const uint8_t ApicId2 = ASMGetApicId();
270	const uint64_t TSC2 = ASMReadTSC();
271	const uint8_t ApicId3 = ASMGetApicId();
272	const uint64_t TSC3 = ASMReadTSC();
273	const uint8_t ApicId4 = ASMGetApicId();
274	const uint64_t TSC4 = ASMReadTSC();
275	ASMAtomicXchgU32(&g_u32Go, 2);
276	const uint8_t ApicId5 = ASMGetApicId();
277	const uint64_t TSC5 = ASMReadTSC();
278	const uint8_t ApicId6 = ASMGetApicId();
279
280	/* Compose our own result. */
281	if ( ApicId1 == ApicId2
282	&& ApicId1 == ApicId3
283	&& ApicId1 == ApicId4
284	&& ApicId1 == ApicId5
285	&& ApicId1 == ApicId6
286	&& TSC5 - TSC1 < 2750 /* WARNING: This is just a guess, increase if it doesn't work for you. */
287	&& TSC4 - TSC1 < TSC5 - TSC1
288	&& TSC3 - TSC1 < TSC4 - TSC1
289	&& TSC2 - TSC1 < TSC3 - TSC1
290	)
291	{
292	/* succeeded. */
293	s_aData[0].TSC = TSC2;
294	s_aData[0].u8ApicId = ApicId1;
295	s_aData[0].fFailed = false;
296	s_aData[0].fRead = true;
297	ASMAtomicIncU32(&g_cRead);
298	}
299	else
300	{
301	/* failed */
302	s_aData[0].fFailed = true;
303	s_aData[0].fRead = false;
304	ASMAtomicIncU32(&g_cFailed);
305	}
306
307	/*
308	* Wait a little while to let the other ones to finish.
309	*/
310	i = 0;
311	while (g_cRead + g_cFailed < cCpus)
312	{
313	if (i++ > _2G32)
314	break;
315	if (i > _1M)
316	RTThreadSleep(i & 0xf);
317	}
318	if (g_cRead + g_cFailed != cCpus)
319	{
320	RTPrintf("tstTSC: FAILURE - threads failed to complete reading (%d + %d != %d)\n", g_cRead, g_cFailed, cCpus);
321	break;
322	}
323
324	/*
325	* If everone succeeded, print the results.
326	*/
327	if (!g_cFailed)
328	{
329	/* sort it by apic id first. */
330	bool fDone;
331	do
332	{
333	for (i = 1, fDone = true; i < cCpus; i++)
334	if (s_aData[i - 1].u8ApicId > s_aData[i].u8ApicId)
335	{
336	TSCDATA Tmp = s_aData[i - 1];
337	s_aData[i - 1] = s_aData[i];
338	s_aData[i] = Tmp;
339	fDone = false;
340	}
341	} while (!fDone);
342
343	RTPrintf(" # ID TSC delta0 (decimal)\n"
344	"-----------------------------------------\n");
345	RTPrintf("%2d %02x %RX64\n", 0, s_aData[0].u8ApicId, s_aData[0].TSC);
346	for (i = 1; i < cCpus; i++)
347	RTPrintf("%2d %02x %RX64 %s%lld\n", i, s_aData[i].u8ApicId, s_aData[i].TSC,
348	s_aData[i].TSC > s_aData[0].TSC ? "+" : "", s_aData[i].TSC - s_aData[0].TSC);
349	RTPrintf("(Needed %u attempt%s.)\n", cTries + 1, cTries ? "s" : "");
350	break;
351	}
352	}
353
354	/*
355	* Destroy the threads.
356	*/
357	ASMAtomicXchgSize(&g_fDone, true);
358	for (i = 0; i < cCpus; i++)
359	if (s_aData[i].Thread != RTThreadSelf())
360	{
361	int rc = RTThreadUserSignal(s_aData[i].Thread);
362	if (RT_FAILURE(rc))
363	RTPrintf("tstTSC: WARNING - RTThreadUserSignal(%#u) -> rc=%Rrc! (2)\n", i, rc);
364	}
365	for (i = 0; i < cCpus; i++)
366	if (s_aData[i].Thread != RTThreadSelf())
367	{
368	int rc = RTThreadWait(s_aData[i].Thread, 5000, NULL);
369	if (RT_FAILURE(rc))
370	RTPrintf("tstTSC: WARNING - RTThreadWait(%#u) -> rc=%Rrc!\n", i, rc);
371	}
372
373	return g_cFailed != 0 \|\| g_cRead != cCpus;
374	}
375
376
377	static int tstTSCCalcFrequency(uint32_t cMsDuration)
378	{
379	/*
380	* Sample the TSC and time, sleep the requested time and calc the deltas.
381	*/
382	uint64_t uNanoTS = RTTimeSystemNanoTS();
383	uint64_t uTSC = ASMReadTSC();
384	RTThreadSleep(cMsDuration);
385	uNanoTS = RTTimeSystemNanoTS() - uNanoTS;
386	uTSC = ASMReadTSC() - uTSC;
387
388	/*
389	* Calc the frequency.
390	*/
391	RTPrintf("tstTSC: %RU64 ticks in %RU64 ns\n", uTSC, uNanoTS);
392	uint64_t cHz = uTSC / ((long double)uNanoTS / (long double)1000000000);
393	RTPrintf("tstTSC: Frequency %RU64 Hz", cHz);
394	if (cHz > _1G)
395	{
396	cHz += _1G / 20;
397	RTPrintf(" %RU64.%RU64 GHz", cHz / _1G, (cHz % _1G) / (_1G / 10));
398	}
399	else if (cHz > _1M)
400	{
401	cHz += _1M / 20;
402	RTPrintf(" %RU64.%RU64 MHz", cHz / _1M, (cHz % _1M) / (_1M / 10));
403	}
404	RTPrintf("\n");
405	return 0;
406	}
407
408
409	int main(int argc, char **argv)
410	{
411	RTR3Init();
412
413	/*
414	* Parse arguments.
415	*/
416	bool fCalcFrequency = false;
417	uint32_t cMsDuration = 1000; /* 1 sec */
418	static const RTOPTIONDEF s_aOptions[] =
419	{
420	{ "--duration", 'd', RTGETOPT_REQ_UINT32 },
421	{ "--calc-frequency", 'f', RTGETOPT_REQ_NOTHING },
422	{ "--help", 'h', RTGETOPT_REQ_NOTHING }
423	};
424	int iArg = 1;
425	int ch;
426	RTOPTIONUNION Value;
427	while ((ch = RTGetOpt(argc, argv, s_aOptions, RT_ELEMENTS(s_aOptions), &iArg, &Value)))
428	switch (ch)
429	{
430	case 'd': cMsDuration = Value.u32; break;
431	case 'f': fCalcFrequency = true; break;
432	case 'h':
433	RTPrintf("usage: tstTSC\n"
434	" or: tstTSC <-f\|--calc-frequency> [--duration\|-d ms]\n");
435	return 1;
436	default:
437	RTStrmPrintf(g_pStdErr, "tstTSC: Unknown arg or error (ch=%d)\n", ch);
438	return 1;
439	}
440	if (iArg != argc)
441	{
442	RTStrmPrintf(g_pStdErr, "tstTSC: too many arguments\n");
443	return 1;
444	}
445
446	if (fCalcFrequency)
447	return tstTSCCalcFrequency(cMsDuration);
448	return tstTSCCalcDrift();
449	}
450

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source: vbox/trunk/src/VBox/Runtime/testcase/tstTSC.cpp@ 16684

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