/* $Id: TMAllCpu.cpp 12549 2008-09-17 18:02:02Z vboxsync $ */ /** @file * TM - Timeout Manager, CPU Time, All Contexts. */ /* * Copyright (C) 2006-2007 Sun Microsystems, Inc. * * 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. * * Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa * Clara, CA 95054 USA or visit http://www.sun.com if you need * additional information or have any questions. */ /******************************************************************************* * Header Files * *******************************************************************************/ #define LOG_GROUP LOG_GROUP_TM #include #include "../TMInternal.h" #include #include #include #include #include #include #include /** * Gets the raw cpu tick from current virtual time. */ DECLINLINE(uint64_t) tmCpuTickGetRawVirtual(PVM pVM, bool fCheckTimers) { uint64_t u64 = TMVirtualSyncGetEx(pVM, fCheckTimers); if (u64 != TMCLOCK_FREQ_VIRTUAL) u64 = ASMMultU64ByU32DivByU32(u64, pVM->tm.s.cTSCTicksPerSecond, TMCLOCK_FREQ_VIRTUAL); return u64; } /** * Resumes the CPU timestamp counter ticking. * * @returns VBox status code. * @param pVM The VM to operate on. * @internal */ int tmCpuTickResume(PVM pVM) { if (!pVM->tm.s.fTSCTicking) { pVM->tm.s.fTSCTicking = true; if (pVM->tm.s.fTSCVirtualized) { if (pVM->tm.s.fTSCUseRealTSC) pVM->tm.s.u64TSCOffset = ASMReadTSC() - pVM->tm.s.u64TSC; else pVM->tm.s.u64TSCOffset = tmCpuTickGetRawVirtual(pVM, false /* don't check for pending timers */) - pVM->tm.s.u64TSC; } return VINF_SUCCESS; } AssertFailed(); return VERR_INTERNAL_ERROR; } /** * Resumes the CPU timestamp counter ticking. * * @returns VBox status code. * @param pVM The VM to operate on. * @todo replace this with TMNotifyResume */ TMDECL(int) TMCpuTickResume(PVM pVM) { if (!pVM->tm.s.fTSCTiedToExecution) return tmCpuTickResume(pVM); /* ignored */ return VINF_SUCCESS; } /** * Pauses the CPU timestamp counter ticking. * * @returns VBox status code. * @param pVM The VM to operate on. * @internal */ int tmCpuTickPause(PVM pVM) { if (pVM->tm.s.fTSCTicking) { pVM->tm.s.u64TSC = TMCpuTickGet(pVM); pVM->tm.s.fTSCTicking = false; return VINF_SUCCESS; } AssertFailed(); return VERR_INTERNAL_ERROR; } /** * Pauses the CPU timestamp counter ticking. * * @returns VBox status code. * @param pVM The VM to operate on. * @todo replace this with TMNotifySuspend */ TMDECL(int) TMCpuTickPause(PVM pVM) { if (!pVM->tm.s.fTSCTiedToExecution) return tmCpuTickPause(pVM); /* ignored */ return VINF_SUCCESS; } /** * Checks if AMD-V / VT-x can use an offsetted hardware TSC or not. * * @returns true/false accordingly. * @param pVM The VM handle. * @param poffRealTSC The offset against the TSC of the current CPU. * Can be NULL. * @thread EMT. */ TMDECL(bool) TMCpuTickCanUseRealTSC(PVM pVM, uint64_t *poffRealTSC) { /* * We require: * 1. A fixed TSC, this is checked at init time. * 2. That the TSC is ticking (we shouldn't be here if it isn't) * 3. Either that we're using the real TSC as time source or * a) we don't have any lag to catch up, and * b) the virtual sync clock hasn't been halted by an expired timer, and * c) we're not using warp drive (accelerated virtual guest time). */ if ( pVM->tm.s.fMaybeUseOffsettedHostTSC && RT_LIKELY(pVM->tm.s.fTSCTicking) && ( pVM->tm.s.fTSCUseRealTSC || ( !pVM->tm.s.fVirtualSyncCatchUp && RT_LIKELY(pVM->tm.s.fVirtualSyncTicking) && !pVM->tm.s.fVirtualWarpDrive)) ) { if (!pVM->tm.s.fTSCUseRealTSC) { /* The source is the timer synchronous virtual clock. */ Assert(pVM->tm.s.fTSCVirtualized); if (poffRealTSC) { uint64_t u64Now = tmCpuTickGetRawVirtual(pVM, false /* don't check for pending timers */) - pVM->tm.s.u64TSCOffset; /** @todo When we start collecting statistics on how much time we spend executing * guest code before exiting, we should check this against the next virtual sync * timer timeout. If it's lower than the avg. length, we should trap rdtsc to increase * the chance that we'll get interrupted right after the timer expired. */ *poffRealTSC = u64Now - ASMReadTSC(); } } else if (poffRealTSC) { /* The source is the real TSC. */ if (pVM->tm.s.fTSCVirtualized) *poffRealTSC = pVM->tm.s.u64TSCOffset; else *poffRealTSC = 0; } return true; } return false; } /** * Read the current CPU timstamp counter. * * @returns Gets the CPU tsc. * @param pVM The VM to operate on. */ TMDECL(uint64_t) TMCpuTickGet(PVM pVM) { uint64_t u64; if (RT_LIKELY(pVM->tm.s.fTSCTicking)) { if (pVM->tm.s.fTSCVirtualized) { if (pVM->tm.s.fTSCUseRealTSC) u64 = ASMReadTSC(); else u64 = tmCpuTickGetRawVirtual(pVM, true /* check for pending timers */); u64 -= pVM->tm.s.u64TSCOffset; } else u64 = ASMReadTSC(); } else u64 = pVM->tm.s.u64TSC; return u64; } /** * Sets the current CPU timestamp counter. * * @returns VBox status code. * @param pVM The VM to operate on. * @param u64Tick The new timestamp value. */ TMDECL(int) TMCpuTickSet(PVM pVM, uint64_t u64Tick) { Assert(!pVM->tm.s.fTSCTicking); pVM->tm.s.u64TSC = u64Tick; return VINF_SUCCESS; } /** * Get the timestamp frequency. * * @returns Number of ticks per second. * @param pVM The VM. */ TMDECL(uint64_t) TMCpuTicksPerSecond(PVM pVM) { if (pVM->tm.s.fTSCUseRealTSC) { uint64_t cTSCTicksPerSecond = SUPGetCpuHzFromGIP(g_pSUPGlobalInfoPage); if (RT_LIKELY(cTSCTicksPerSecond != ~(uint64_t)0)) return cTSCTicksPerSecond; } return pVM->tm.s.cTSCTicksPerSecond; }