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-rw-r--r--src/VBox/Runtime/testcase/tstTSC.cpp451
1 files changed, 451 insertions, 0 deletions
diff --git a/src/VBox/Runtime/testcase/tstTSC.cpp b/src/VBox/Runtime/testcase/tstTSC.cpp
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+++ b/src/VBox/Runtime/testcase/tstTSC.cpp
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+/* $Id: tstTSC.cpp $ */
+/** @file
+ * IPRT Testcase - SMP TSC testcase.
+ */
+
+/*
+ * Copyright (C) 2006-2019 Oracle Corporation
+ *
+ * This file is part of VirtualBox Open Source Edition (OSE), as
+ * available from http://www.virtualbox.org. This file is free software;
+ * you can redistribute it and/or modify it under the terms of the GNU
+ * General Public License (GPL) as published by the Free Software
+ * Foundation, in version 2 as it comes in the "COPYING" file of the
+ * VirtualBox OSE distribution. VirtualBox OSE is distributed in the
+ * hope that it will be useful, but WITHOUT ANY WARRANTY of any kind.
+ *
+ * The contents of this file may alternatively be used under the terms
+ * of the Common Development and Distribution License Version 1.0
+ * (CDDL) only, as it comes in the "COPYING.CDDL" file of the
+ * VirtualBox OSE distribution, in which case the provisions of the
+ * CDDL are applicable instead of those of the GPL.
+ *
+ * You may elect to license modified versions of this file under the
+ * terms and conditions of either the GPL or the CDDL or both.
+ */
+
+
+/*********************************************************************************************************************************
+* Header Files *
+*********************************************************************************************************************************/
+#include <iprt/asm-amd64-x86.h>
+#include <iprt/asm.h>
+#include <iprt/getopt.h>
+#include <iprt/initterm.h>
+#include <iprt/mp.h>
+#include <iprt/stream.h>
+#include <iprt/string.h>
+#include <iprt/thread.h>
+#include <iprt/time.h>
+
+
+/*********************************************************************************************************************************
+* Structures and Typedefs *
+*********************************************************************************************************************************/
+typedef struct TSCDATA
+{
+ /** The TSC. */
+ uint64_t volatile TSC;
+ /** The APIC ID. */
+ uint8_t volatile u8ApicId;
+ /** Did it succeed? */
+ bool volatile fRead;
+ /** Did it fail? */
+ bool volatile fFailed;
+ /** The thread handle. */
+ RTTHREAD Thread;
+} TSCDATA, *PTSCDATA;
+
+
+/*********************************************************************************************************************************
+* Global Variables *
+*********************************************************************************************************************************/
+/** The number of CPUs waiting on their user event semaphore. */
+static volatile uint32_t g_cWaiting;
+/** The number of CPUs ready (in spin) to do the TSC read. */
+static volatile uint32_t g_cReady;
+/** The variable the CPUs are spinning on.
+ * 0: Spin.
+ * 1: Go ahead.
+ * 2: You're too late, back to square one. */
+static volatile uint32_t g_u32Go;
+/** The number of CPUs that managed to read the TSC. */
+static volatile uint32_t g_cRead;
+/** The number of CPUs that failed to read the TSC. */
+static volatile uint32_t g_cFailed;
+
+/** Indicator forcing the threads to quit. */
+static volatile bool g_fDone;
+
+
+/*********************************************************************************************************************************
+* Internal Functions *
+*********************************************************************************************************************************/
+static DECLCALLBACK(int) ThreadFunction(RTTHREAD Thread, void *pvUser);
+
+
+/**
+ * Thread function for catching the other cpus.
+ *
+ * @returns VINF_SUCCESS (we don't care).
+ * @param Thread The thread handle.
+ * @param pvUser PTSCDATA.
+ */
+static DECLCALLBACK(int) ThreadFunction(RTTHREAD Thread, void *pvUser)
+{
+ PTSCDATA pTscData = (PTSCDATA)pvUser;
+
+ while (!g_fDone)
+ {
+ /*
+ * Wait.
+ */
+ ASMAtomicIncU32(&g_cWaiting);
+ RTThreadUserWait(Thread, RT_INDEFINITE_WAIT);
+ RTThreadUserReset(Thread);
+ ASMAtomicDecU32(&g_cWaiting);
+ if (g_fDone)
+ break;
+
+ /*
+ * Spin.
+ */
+ ASMAtomicIncU32(&g_cReady);
+ while (!g_fDone)
+ {
+ const uint8_t ApicId1 = ASMGetApicId();
+ const uint64_t TSC1 = ASMReadTSC();
+ const uint32_t u32Go = g_u32Go;
+ if (u32Go == 0)
+ continue;
+
+ if (u32Go == 1)
+ {
+ /* do the reading. */
+ const uint8_t ApicId2 = ASMGetApicId();
+ const uint64_t TSC2 = ASMReadTSC();
+ const uint8_t ApicId3 = ASMGetApicId();
+ const uint64_t TSC3 = ASMReadTSC();
+ const uint8_t ApicId4 = ASMGetApicId();
+
+ if ( ApicId1 == ApicId2
+ && ApicId1 == ApicId3
+ && ApicId1 == ApicId4
+ && TSC3 - TSC1 < 2250 /* WARNING: This is just a guess, increase if it doesn't work for you. */
+ && TSC2 - TSC1 < TSC3 - TSC1
+ )
+ {
+ /* succeeded. */
+ pTscData->TSC = TSC2;
+ pTscData->u8ApicId = ApicId1;
+ pTscData->fFailed = false;
+ pTscData->fRead = true;
+ ASMAtomicIncU32(&g_cRead);
+ break;
+ }
+ }
+
+ /* failed */
+ pTscData->fFailed = true;
+ pTscData->fRead = false;
+ ASMAtomicIncU32(&g_cFailed);
+ break;
+ }
+ }
+
+ return VINF_SUCCESS;
+}
+
+static int tstTSCCalcDrift(void)
+{
+ /*
+ * This is only relevant to on SMP systems.
+ */
+ const unsigned cCpus = RTMpGetOnlineCount();
+ if (cCpus <= 1)
+ {
+ RTPrintf("tstTSC: SKIPPED - Only relevant on SMP systems\n");
+ return 0;
+ }
+
+ /*
+ * Create the threads.
+ */
+ static TSCDATA s_aData[254];
+ uint32_t i;
+ if (cCpus > RT_ELEMENTS(s_aData))
+ {
+ RTPrintf("tstTSC: FAILED - too many CPUs (%u)\n", cCpus);
+ return 1;
+ }
+
+ /* ourselves. */
+ s_aData[0].Thread = RTThreadSelf();
+
+ /* the others */
+ for (i = 1; i < cCpus; i++)
+ {
+ int rc = RTThreadCreate(&s_aData[i].Thread, ThreadFunction, &s_aData[i], 0, RTTHREADTYPE_TIMER, RTTHREADFLAGS_WAITABLE, "OTHERCPU");
+ if (RT_FAILURE(rc))
+ {
+ RTPrintf("tstTSC: FAILURE - RTThreatCreate failed when creating thread #%u, rc=%Rrc!\n", i, rc);
+ ASMAtomicXchgSize(&g_fDone, true);
+ while (i-- > 1)
+ {
+ RTThreadUserSignal(s_aData[i].Thread);
+ RTThreadWait(s_aData[i].Thread, 5000, NULL);
+ }
+ return 1;
+ }
+ }
+
+ /*
+ * Retry until we get lucky (or give up).
+ */
+ for (unsigned cTries = 0; ; cTries++)
+ {
+ if (cTries > 10240)
+ {
+ RTPrintf("tstTSC: FAILURE - %d attempts, giving.\n", cTries);
+ break;
+ }
+
+ /*
+ * Wait for the other threads to get ready (brute force active wait, I'm lazy).
+ */
+ i = 0;
+ while (g_cWaiting < cCpus - 1)
+ {
+ if (i++ > _2G32)
+ break;
+ RTThreadSleep(i & 0xf);
+ }
+ if (g_cWaiting != cCpus - 1)
+ {
+ RTPrintf("tstTSC: FAILURE - threads failed to get waiting (%d != %d (i=%d))\n", g_cWaiting + 1, cCpus, i);
+ break;
+ }
+
+ /*
+ * Send them spinning.
+ */
+ ASMAtomicXchgU32(&g_cReady, 0);
+ ASMAtomicXchgU32(&g_u32Go, 0);
+ ASMAtomicXchgU32(&g_cRead, 0);
+ ASMAtomicXchgU32(&g_cFailed, 0);
+ for (i = 1; i < cCpus; i++)
+ {
+ ASMAtomicXchgSize(&s_aData[i].fFailed, false);
+ ASMAtomicXchgSize(&s_aData[i].fRead, false);
+ ASMAtomicXchgU8(&s_aData[i].u8ApicId, 0xff);
+
+ int rc = RTThreadUserSignal(s_aData[i].Thread);
+ if (RT_FAILURE(rc))
+ RTPrintf("tstTSC: WARNING - RTThreadUserSignal(%#u) -> rc=%Rrc!\n", i, rc);
+ }
+
+ /* wait for them to get ready. */
+ i = 0;
+ while (g_cReady < cCpus - 1)
+ {
+ if (i++ > _2G32)
+ break;
+ }
+ if (g_cReady != cCpus - 1)
+ {
+ RTPrintf("tstTSC: FAILURE - threads failed to get ready (%d != %d, i=%d)\n", g_cWaiting + 1, cCpus, i);
+ break;
+ }
+
+ /*
+ * Flip the "go" switch and do our readings.
+ * We give the other threads the slack it takes to two extra TSC and APIC ID reads.
+ */
+ const uint8_t ApicId1 = ASMGetApicId();
+ const uint64_t TSC1 = ASMReadTSC();
+ ASMAtomicXchgU32(&g_u32Go, 1);
+ const uint8_t ApicId2 = ASMGetApicId();
+ const uint64_t TSC2 = ASMReadTSC();
+ const uint8_t ApicId3 = ASMGetApicId();
+ const uint64_t TSC3 = ASMReadTSC();
+ const uint8_t ApicId4 = ASMGetApicId();
+ const uint64_t TSC4 = ASMReadTSC();
+ ASMAtomicXchgU32(&g_u32Go, 2);
+ const uint8_t ApicId5 = ASMGetApicId();
+ const uint64_t TSC5 = ASMReadTSC();
+ const uint8_t ApicId6 = ASMGetApicId();
+
+ /* Compose our own result. */
+ if ( ApicId1 == ApicId2
+ && ApicId1 == ApicId3
+ && ApicId1 == ApicId4
+ && ApicId1 == ApicId5
+ && ApicId1 == ApicId6
+ && TSC5 - TSC1 < 2750 /* WARNING: This is just a guess, increase if it doesn't work for you. */
+ && TSC4 - TSC1 < TSC5 - TSC1
+ && TSC3 - TSC1 < TSC4 - TSC1
+ && TSC2 - TSC1 < TSC3 - TSC1
+ )
+ {
+ /* succeeded. */
+ s_aData[0].TSC = TSC2;
+ s_aData[0].u8ApicId = ApicId1;
+ s_aData[0].fFailed = false;
+ s_aData[0].fRead = true;
+ ASMAtomicIncU32(&g_cRead);
+ }
+ else
+ {
+ /* failed */
+ s_aData[0].fFailed = true;
+ s_aData[0].fRead = false;
+ ASMAtomicIncU32(&g_cFailed);
+ }
+
+ /*
+ * Wait a little while to let the other ones to finish.
+ */
+ i = 0;
+ while (g_cRead + g_cFailed < cCpus)
+ {
+ if (i++ > _2G32)
+ break;
+ if (i > _1M)
+ RTThreadSleep(i & 0xf);
+ }
+ if (g_cRead + g_cFailed != cCpus)
+ {
+ RTPrintf("tstTSC: FAILURE - threads failed to complete reading (%d + %d != %d)\n", g_cRead, g_cFailed, cCpus);
+ break;
+ }
+
+ /*
+ * If everone succeeded, print the results.
+ */
+ if (!g_cFailed)
+ {
+ /* sort it by apic id first. */
+ bool fDone;
+ do
+ {
+ for (i = 1, fDone = true; i < cCpus; i++)
+ if (s_aData[i - 1].u8ApicId > s_aData[i].u8ApicId)
+ {
+ TSCDATA Tmp = s_aData[i - 1];
+ s_aData[i - 1] = s_aData[i];
+ s_aData[i] = Tmp;
+ fDone = false;
+ }
+ } while (!fDone);
+
+ RTPrintf(" # ID TSC delta0 (decimal)\n"
+ "-----------------------------------------\n");
+ RTPrintf("%2d %02x %RX64\n", 0, s_aData[0].u8ApicId, s_aData[0].TSC);
+ for (i = 1; i < cCpus; i++)
+ RTPrintf("%2d %02x %RX64 %s%lld\n", i, s_aData[i].u8ApicId, s_aData[i].TSC,
+ s_aData[i].TSC > s_aData[0].TSC ? "+" : "", s_aData[i].TSC - s_aData[0].TSC);
+ RTPrintf("(Needed %u attempt%s.)\n", cTries + 1, cTries ? "s" : "");
+ break;
+ }
+ }
+
+ /*
+ * Destroy the threads.
+ */
+ ASMAtomicXchgSize(&g_fDone, true);
+ for (i = 0; i < cCpus; i++)
+ if (s_aData[i].Thread != RTThreadSelf())
+ {
+ int rc = RTThreadUserSignal(s_aData[i].Thread);
+ if (RT_FAILURE(rc))
+ RTPrintf("tstTSC: WARNING - RTThreadUserSignal(%#u) -> rc=%Rrc! (2)\n", i, rc);
+ }
+ for (i = 0; i < cCpus; i++)
+ if (s_aData[i].Thread != RTThreadSelf())
+ {
+ int rc = RTThreadWait(s_aData[i].Thread, 5000, NULL);
+ if (RT_FAILURE(rc))
+ RTPrintf("tstTSC: WARNING - RTThreadWait(%#u) -> rc=%Rrc!\n", i, rc);
+ }
+
+ return g_cFailed != 0 || g_cRead != cCpus;
+}
+
+
+static int tstTSCCalcFrequency(uint32_t cMsDuration)
+{
+ /*
+ * Sample the TSC and time, sleep the requested time and calc the deltas.
+ */
+ uint64_t uNanoTS = RTTimeSystemNanoTS();
+ uint64_t uTSC = ASMReadTSC();
+ RTThreadSleep(cMsDuration);
+ uNanoTS = RTTimeSystemNanoTS() - uNanoTS;
+ uTSC = ASMReadTSC() - uTSC;
+
+ /*
+ * Calc the frequency.
+ */
+ RTPrintf("tstTSC: %RU64 ticks in %RU64 ns\n", uTSC, uNanoTS);
+ uint64_t cHz = (uint64_t)(uTSC / ((long double)uNanoTS / (long double)1000000000));
+ RTPrintf("tstTSC: Frequency %RU64 Hz", cHz);
+ if (cHz > _1G)
+ {
+ cHz += _1G / 20;
+ RTPrintf(" %RU64.%RU64 GHz", cHz / _1G, (cHz % _1G) / (_1G / 10));
+ }
+ else if (cHz > _1M)
+ {
+ cHz += _1M / 20;
+ RTPrintf(" %RU64.%RU64 MHz", cHz / _1M, (cHz % _1M) / (_1M / 10));
+ }
+ RTPrintf("\n");
+ return 0;
+}
+
+
+int main(int argc, char **argv)
+{
+ RTR3InitExe(argc, &argv, 0);
+
+ /*
+ * Parse arguments.
+ */
+ bool fCalcFrequency = false;
+ uint32_t cMsDuration = 1000; /* 1 sec */
+ static const RTGETOPTDEF s_aOptions[] =
+ {
+ { "--duration", 'd', RTGETOPT_REQ_UINT32 },
+ { "--calc-frequency", 'f', RTGETOPT_REQ_NOTHING },
+ };
+ int ch;
+ RTGETOPTUNION Value;
+ RTGETOPTSTATE GetState;
+ RTGetOptInit(&GetState, argc, argv, s_aOptions, RT_ELEMENTS(s_aOptions), 1, 0 /* fFlags */);
+ while ((ch = RTGetOpt(&GetState, &Value)))
+ switch (ch)
+ {
+ case 'd': cMsDuration = Value.u32;
+ break;
+
+ case 'f': fCalcFrequency = true;
+ break;
+
+ case 'h':
+ RTPrintf("usage: tstTSC\n"
+ " or: tstTSC <-f|--calc-frequency> [--duration|-d ms]\n");
+ return 1;
+
+ case 'V':
+ RTPrintf("$Revision: 127855 $\n");
+ return 0;
+
+ default:
+ return RTGetOptPrintError(ch, &Value);
+ }
+
+ if (fCalcFrequency)
+ return tstTSCCalcFrequency(cMsDuration);
+ return tstTSCCalcDrift();
+}
+
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