/* $Id: PDMCritSect.cpp 14657 2008-11-26 18:08:15Z vboxsync $ */ /** @file * PDM - Critical Sections, Ring-3. */ /* * 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_PDM//_CRITSECT #include "PDMInternal.h" #include #include #include #include #include #include #include #include /******************************************************************************* * Internal Functions * *******************************************************************************/ static int pdmR3CritSectDeleteOne(PVM pVM, PPDMCRITSECTINT pCritSect, PPDMCRITSECTINT pPrev, bool fFinal); /** * Initializes the critical section subcomponent. * * @returns VBox status code. * @param pVM The VM handle. * @remark Not to be confused with PDMR3CritSectInit and pdmR3CritSectInitDevice which are * for initializing a critical section. */ int pdmR3CritSectInit(PVM pVM) { STAM_REG(pVM, &pVM->pdm.s.StatQueuedCritSectLeaves, STAMTYPE_COUNTER, "/PDM/QueuedCritSectLeaves", STAMUNIT_OCCURENCES, "Number of times a critical section leave requesed needed to be queued for ring-3 execution."); return VINF_SUCCESS; } /** * Relocates all the critical sections. * * @param pVM The VM handle. */ void pdmR3CritSectRelocate(PVM pVM) { for (PPDMCRITSECTINT pCur = pVM->pdm.s.pCritSects; pCur; pCur = pCur->pNext) pCur->pVMRC = pVM->pVMRC; } /** * Deletes all remaining critical sections. * * This is called at the end of the termination process. * * @returns VBox status. * First error code, rest is lost. * @param pVM The VM handle. * @remark Don't confuse this with PDMR3CritSectDelete. */ VMMDECL(int) PDMR3CritSectTerm(PVM pVM) { int rc = VINF_SUCCESS; while (pVM->pdm.s.pCritSects) { int rc2 = pdmR3CritSectDeleteOne(pVM, pVM->pdm.s.pCritSects, NULL, true /* final */); AssertRC(rc2); if (RT_FAILURE(rc2) && RT_SUCCESS(rc)) rc = rc2; } return rc; } /** * Initalizes a critical section and inserts it into the list. * * @returns VBox status code. * @param pVM The Vm handle. * @param pCritSect The critical section. * @param pvKey The owner key. * @param pszName The name of the critical section (for statistics). */ static int pdmR3CritSectInitOne(PVM pVM, PPDMCRITSECTINT pCritSect, void *pvKey, const char *pszName) { VM_ASSERT_EMT(pVM); int rc = RTCritSectInit(&pCritSect->Core); if (RT_SUCCESS(rc)) { pCritSect->pVMR3 = pVM; pCritSect->pVMR0 = pVM->pVMR0; pCritSect->pVMRC = pVM->pVMRC; pCritSect->pvKey = pvKey; pCritSect->EventToSignal = NIL_RTSEMEVENT; pCritSect->pNext = pVM->pdm.s.pCritSects; pVM->pdm.s.pCritSects = pCritSect; #ifdef VBOX_WITH_STATISTICS STAMR3RegisterF(pVM, &pCritSect->StatContentionRZLock, STAMTYPE_COUNTER, STAMVISIBILITY_ALWAYS, STAMUNIT_OCCURENCES, NULL, "/PDM/CritSects/%s/ContentionRZLock", pszName); STAMR3RegisterF(pVM, &pCritSect->StatContentionRZUnlock,STAMTYPE_COUNTER, STAMVISIBILITY_ALWAYS, STAMUNIT_OCCURENCES, NULL, "/PDM/CritSects/%s/ContentionRZUnlock", pszName); STAMR3RegisterF(pVM, &pCritSect->StatContentionR3, STAMTYPE_COUNTER, STAMVISIBILITY_ALWAYS, STAMUNIT_OCCURENCES, NULL, "/PDM/CritSects/%s/ContentionR3", pszName); STAMR3RegisterF(pVM, &pCritSect->StatLocked, STAMTYPE_PROFILE_ADV, STAMVISIBILITY_ALWAYS, STAMUNIT_TICKS_PER_OCCURENCE, NULL, "/PDM/CritSects/%s/Locked", pszName); #endif } return rc; } /** * Initializes a PDM critical section for internal use. * * The PDM critical sections are derived from the IPRT critical sections, but * works in GC as well. * * @returns VBox status code. * @param pVM The VM handle. * @param pDevIns Device instance. * @param pCritSect Pointer to the critical section. * @param pszName The name of the critical section (for statistics). */ VMMR3DECL(int) PDMR3CritSectInit(PVM pVM, PPDMCRITSECT pCritSect, const char *pszName) { #if HC_ARCH_BITS == 64 && GC_ARCH_BITS == 32 AssertCompile(sizeof(pCritSect->padding) >= sizeof(pCritSect->s)); #endif return pdmR3CritSectInitOne(pVM, &pCritSect->s, pCritSect, pszName); } /** * Initializes a PDM critical section. * * The PDM critical sections are derived from the IPRT critical sections, but * works in GC as well. * * @returns VBox status code. * @param pVM The VM handle. * @param pDevIns Device instance. * @param pCritSect Pointer to the critical section. * @param pszName The name of the critical section (for statistics). */ int pdmR3CritSectInitDevice(PVM pVM, PPDMDEVINS pDevIns, PPDMCRITSECT pCritSect, const char *pszName) { return pdmR3CritSectInitOne(pVM, &pCritSect->s, pDevIns, pszName); } /** * Deletes one critical section. * * @returns Return code from RTCritSectDelete. * @param pVM The VM handle. * @param pCritSect The critical section. * @param pPrev The previous critical section in the list. * @param fFinal Set if this is the final call and statistics shouldn't be deregistered. */ static int pdmR3CritSectDeleteOne(PVM pVM, PPDMCRITSECTINT pCritSect, PPDMCRITSECTINT pPrev, bool fFinal) { /* ulink */ if (pPrev) pPrev->pNext = pCritSect->pNext; else pVM->pdm.s.pCritSects = pCritSect->pNext; /* delete */ pCritSect->pNext = NULL; pCritSect->pvKey = NULL; pCritSect->pVMR3 = NULL; pCritSect->pVMR0 = NIL_RTR0PTR; pCritSect->pVMRC = NIL_RTRCPTR; #ifdef VBOX_WITH_STATISTICS if (!fFinal) { STAMR3Deregister(pVM, &pCritSect->StatContentionRZLock); STAMR3Deregister(pVM, &pCritSect->StatContentionRZUnlock); STAMR3Deregister(pVM, &pCritSect->StatContentionR3); STAMR3Deregister(pVM, &pCritSect->StatLocked); } #endif return RTCritSectDelete(&pCritSect->Core); } /** * Deletes all critical sections with a give initializer key. * * @returns VBox status code. * The entire list is processed on failure, so we'll only * return the first error code. This shouldn't be a problem * since errors really shouldn't happen here. * @param pVM The VM handle. * @param pvKey The initializer key. */ static int pdmR3CritSectDeleteByKey(PVM pVM, void *pvKey) { /* * Iterate the list and match key. */ int rc = VINF_SUCCESS; PPDMCRITSECTINT pPrev = NULL; PPDMCRITSECTINT pCur = pVM->pdm.s.pCritSects; while (pCur) { if (pCur->pvKey == pvKey) { int rc2 = pdmR3CritSectDeleteOne(pVM, pCur, pPrev, false /* not final */); AssertRC(rc2); if (RT_FAILURE(rc2) && RT_SUCCESS(rc)) rc = rc2; } /* next */ pPrev = pCur; pCur = pCur->pNext; } return rc; } /** * Deletes all undeleted critical sections initalized by a given device. * * @returns VBox status code. * @param pVM The VM handle. * @param pDevIns The device handle. */ int pdmR3CritSectDeleteDevice(PVM pVM, PPDMDEVINS pDevIns) { return pdmR3CritSectDeleteByKey(pVM, pDevIns); } /** * Deletes the critical section. * * @returns VBox status code. * @param pCritSect The PDM critical section to destroy. */ VMMR3DECL(int) PDMR3CritSectDelete(PPDMCRITSECT pCritSect) { if (!RTCritSectIsInitialized(&pCritSect->s.Core)) return VINF_SUCCESS; /* * Find and unlink it. */ PVM pVM = pCritSect->s.pVMR3; AssertReleaseReturn(pVM, VERR_INTERNAL_ERROR); PPDMCRITSECTINT pPrev = NULL; PPDMCRITSECTINT pCur = pVM->pdm.s.pCritSects; while (pCur) { if (pCur == &pCritSect->s) return pdmR3CritSectDeleteOne(pVM, pCur, pPrev, false /* not final */); /* next */ pPrev = pCur; pCur = pCur->pNext; } AssertReleaseMsgFailed(("pCritSect=%p wasn't found!\n", pCritSect)); return VERR_INTERNAL_ERROR; } /** * Process the critical sections queued for ring-3 'leave'. * * @param pVM The VM handle. */ VMMR3DECL(void) PDMR3CritSectFF(PVM pVM) { Assert(pVM->pdm.s.cQueuedCritSectLeaves > 0); const RTUINT c = pVM->pdm.s.cQueuedCritSectLeaves; for (RTUINT i = 0; i < c; i++) { PPDMCRITSECT pCritSect = pVM->pdm.s.apQueuedCritSectsLeaves[i]; int rc = RTCritSectLeave(&pCritSect->s.Core); LogFlow(("PDMR3CritSectFF: %p - %Rrc\n", pCritSect, rc)); AssertRC(rc); } pVM->pdm.s.cQueuedCritSectLeaves = 0; VM_FF_CLEAR(pVM, VM_FF_PDM_CRITSECT); } /** * Try enter a critical section. * * @returns VINF_SUCCESS on success. * @returns VERR_SEM_BUSY if the critsect was owned. * @returns VERR_SEM_NESTED if nested enter on a no nesting section. (Asserted.) * @returns VERR_SEM_DESTROYED if RTCritSectDelete was called while waiting. * @param pCritSect The critical section. */ VMMR3DECL(int) PDMR3CritSectTryEnter(PPDMCRITSECT pCritSect) { return RTCritSectTryEnter(&pCritSect->s.Core); } /** * Schedule a event semaphore for signalling upon critsect exit. * * @returns VINF_SUCCESS on success. * @returns VERR_TOO_MANY_SEMAPHORES if an event was already scheduled. * @returns VERR_NOT_OWNER if we're not the critsect owner. * @returns VERR_SEM_DESTROYED if RTCritSectDelete was called while waiting. * @param pCritSect The critical section. * @param EventToSignal The semapore that should be signalled. */ VMMR3DECL(int) PDMR3CritSectScheduleExitEvent(PPDMCRITSECT pCritSect, RTSEMEVENT EventToSignal) { Assert(EventToSignal != NIL_RTSEMEVENT); if (RT_UNLIKELY(!RTCritSectIsOwner(&pCritSect->s.Core))) return VERR_NOT_OWNER; if (RT_LIKELY( pCritSect->s.EventToSignal == NIL_RTSEMEVENT || pCritSect->s.EventToSignal == EventToSignal)) { pCritSect->s.EventToSignal = EventToSignal; return VINF_SUCCESS; } return VERR_TOO_MANY_SEMAPHORES; }