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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-11 08:17:27 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-11 08:17:27 +0000
commitf215e02bf85f68d3a6106c2a1f4f7f063f819064 (patch)
tree6bb5b92c046312c4e95ac2620b10ddf482d3fa8b /src/VBox/Runtime/generic/spinlock-generic.cpp
parentInitial commit. (diff)
downloadvirtualbox-f215e02bf85f68d3a6106c2a1f4f7f063f819064.tar.xz
virtualbox-f215e02bf85f68d3a6106c2a1f4f7f063f819064.zip
Adding upstream version 7.0.14-dfsg.upstream/7.0.14-dfsg
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'src/VBox/Runtime/generic/spinlock-generic.cpp')
-rw-r--r--src/VBox/Runtime/generic/spinlock-generic.cpp237
1 files changed, 237 insertions, 0 deletions
diff --git a/src/VBox/Runtime/generic/spinlock-generic.cpp b/src/VBox/Runtime/generic/spinlock-generic.cpp
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+/* $Id: spinlock-generic.cpp $ */
+/** @file
+ * IPRT - Spinlock, generic implementation.
+ */
+
+/*
+ * Copyright (C) 2006-2023 Oracle and/or its affiliates.
+ *
+ * This file is part of VirtualBox base platform packages, as
+ * available from https://www.virtualbox.org.
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation, in version 3 of the
+ * License.
+ *
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ * General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, see <https://www.gnu.org/licenses>.
+ *
+ * The contents of this file may alternatively be used under the terms
+ * of the Common Development and Distribution License Version 1.0
+ * (CDDL), a copy of it is provided in the "COPYING.CDDL" file included
+ * in the VirtualBox 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.
+ *
+ * SPDX-License-Identifier: GPL-3.0-only OR CDDL-1.0
+ */
+
+
+/*********************************************************************************************************************************
+* Defined Constants And Macros *
+*********************************************************************************************************************************/
+/** @def RT_CFG_SPINLOCK_GENERIC_DO_SLEEP
+ * Force cpu yields after spinning the number of times indicated by the define.
+ * If 0 we will spin forever. */
+#define RT_CFG_SPINLOCK_GENERIC_DO_SLEEP 100000
+
+
+/*********************************************************************************************************************************
+* Header Files *
+*********************************************************************************************************************************/
+#include <iprt/spinlock.h>
+#include "internal/iprt.h"
+
+#include <iprt/alloc.h>
+#include <iprt/asm.h>
+#if defined(RT_ARCH_AMD64) || defined(RT_ARCH_X86)
+# include <iprt/asm-amd64-x86.h>
+#endif
+#include <iprt/errcore.h>
+#include <iprt/assert.h>
+#if RT_CFG_SPINLOCK_GENERIC_DO_SLEEP
+# include <iprt/thread.h>
+#endif
+
+#include "internal/magics.h"
+
+
+/*********************************************************************************************************************************
+* Structures and Typedefs *
+*********************************************************************************************************************************/
+/**
+ * Generic spinlock structure.
+ */
+typedef struct RTSPINLOCKINTERNAL
+{
+ /** Spinlock magic value (RTSPINLOCK_GEN_MAGIC). */
+ uint32_t u32Magic;
+ /** The spinlock creation flags. */
+ uint32_t fFlags;
+ /** The spinlock. */
+ uint32_t volatile fLocked;
+ /** The saved CPU interrupt. */
+ uint32_t volatile fIntSaved;
+} RTSPINLOCKINTERNAL, *PRTSPINLOCKINTERNAL;
+
+
+RTDECL(int) RTSpinlockCreate(PRTSPINLOCK pSpinlock, uint32_t fFlags, const char *pszName)
+{
+ PRTSPINLOCKINTERNAL pThis;
+ AssertReturn(fFlags == RTSPINLOCK_FLAGS_INTERRUPT_SAFE || fFlags == RTSPINLOCK_FLAGS_INTERRUPT_UNSAFE, VERR_INVALID_PARAMETER);
+ RT_NOREF_PV(pszName);
+
+ /*
+ * Allocate.
+ */
+ pThis = (PRTSPINLOCKINTERNAL)RTMemAlloc(sizeof(*pThis));
+ if (!pThis)
+ return VERR_NO_MEMORY;
+
+ /*
+ * Initialize and return.
+ */
+ pThis->u32Magic = RTSPINLOCK_GEN_MAGIC;
+ pThis->fFlags = fFlags;
+ pThis->fIntSaved = 0;
+ ASMAtomicWriteU32(&pThis->fLocked, 0);
+
+ *pSpinlock = pThis;
+ return VINF_SUCCESS;
+}
+RT_EXPORT_SYMBOL(RTSpinlockCreate);
+
+
+RTDECL(int) RTSpinlockDestroy(RTSPINLOCK Spinlock)
+{
+ /*
+ * Validate input.
+ */
+ PRTSPINLOCKINTERNAL pThis = (PRTSPINLOCKINTERNAL)Spinlock;
+ if (!pThis)
+ return VERR_INVALID_PARAMETER;
+ if (pThis->u32Magic != RTSPINLOCK_GEN_MAGIC)
+ {
+ AssertMsgFailed(("Invalid spinlock %p magic=%#x\n", pThis, pThis->u32Magic));
+ return VERR_INVALID_PARAMETER;
+ }
+
+ ASMAtomicIncU32(&pThis->u32Magic);
+ RTMemFree(pThis);
+ return VINF_SUCCESS;
+}
+RT_EXPORT_SYMBOL(RTSpinlockDestroy);
+
+
+RTDECL(void) RTSpinlockAcquire(RTSPINLOCK Spinlock)
+{
+ PRTSPINLOCKINTERNAL pThis = (PRTSPINLOCKINTERNAL)Spinlock;
+ AssertMsg(pThis && pThis->u32Magic == RTSPINLOCK_GEN_MAGIC,
+ ("pThis=%p u32Magic=%08x\n", pThis, pThis ? (int)pThis->u32Magic : 0));
+
+ if (pThis->fFlags & RTSPINLOCK_FLAGS_INTERRUPT_SAFE)
+ {
+#if defined(RT_ARCH_AMD64) || defined(RT_ARCH_X86)
+ uint32_t fIntSaved = ASMGetFlags();
+#endif
+
+#if RT_CFG_SPINLOCK_GENERIC_DO_SLEEP
+ for (;;)
+ {
+#if defined(RT_ARCH_AMD64) || defined(RT_ARCH_X86)
+ ASMIntDisable();
+#endif
+ for (int c = RT_CFG_SPINLOCK_GENERIC_DO_SLEEP; c > 0; c--)
+ {
+ if (ASMAtomicCmpXchgU32(&pThis->fLocked, 1, 0))
+ {
+# if defined(RT_ARCH_AMD64) || defined(RT_ARCH_X86)
+ pThis->fIntSaved = fIntSaved;
+# endif
+ return;
+ }
+ ASMNopPause();
+ }
+#if defined(RT_ARCH_AMD64) || defined(RT_ARCH_X86)
+ ASMSetFlags(fIntSaved);
+#endif
+ RTThreadYield();
+ }
+#else
+ for (;;)
+ {
+#if defined(RT_ARCH_AMD64) || defined(RT_ARCH_X86)
+ ASMIntDisable();
+#endif
+ if (ASMAtomicCmpXchgU32(&pThis->fLocked, 1, 0))
+ {
+# if defined(RT_ARCH_AMD64) || defined(RT_ARCH_X86)
+ pThis->fIntSaved = fIntSaved;
+# endif
+ return;
+ }
+#if defined(RT_ARCH_AMD64) || defined(RT_ARCH_X86)
+ ASMSetFlags(fIntSaved);
+#endif
+ ASMNopPause();
+ }
+#endif
+ }
+ else
+ {
+#if RT_CFG_SPINLOCK_GENERIC_DO_SLEEP
+ for (;;)
+ {
+ for (int c = RT_CFG_SPINLOCK_GENERIC_DO_SLEEP; c > 0; c--)
+ {
+ if (ASMAtomicCmpXchgU32(&pThis->fLocked, 1, 0))
+ return;
+ ASMNopPause();
+ }
+ RTThreadYield();
+ }
+#else
+ while (!ASMAtomicCmpXchgU32(&pThis->fLocked, 1, 0))
+ ASMNopPause();
+#endif
+ }
+}
+RT_EXPORT_SYMBOL(RTSpinlockAcquire);
+
+
+RTDECL(void) RTSpinlockRelease(RTSPINLOCK Spinlock)
+{
+ PRTSPINLOCKINTERNAL pThis = (PRTSPINLOCKINTERNAL)Spinlock;
+ AssertMsg(pThis && pThis->u32Magic == RTSPINLOCK_GEN_MAGIC,
+ ("pThis=%p u32Magic=%08x\n", pThis, pThis ? (int)pThis->u32Magic : 0));
+
+ if (pThis->fFlags & RTSPINLOCK_FLAGS_INTERRUPT_SAFE)
+ {
+#if defined(RT_ARCH_AMD64) || defined(RT_ARCH_X86)
+ uint32_t fIntSaved = pThis->fIntSaved;
+ pThis->fIntSaved = 0;
+#endif
+
+ if (!ASMAtomicCmpXchgU32(&pThis->fLocked, 0, 1))
+ AssertMsgFailed(("Spinlock %p was not locked!\n", pThis));
+
+#if defined(RT_ARCH_AMD64) || defined(RT_ARCH_X86)
+ ASMSetFlags(fIntSaved);
+#endif
+ }
+ else
+ {
+ if (!ASMAtomicCmpXchgU32(&pThis->fLocked, 0, 1))
+ AssertMsgFailed(("Spinlock %p was not locked!\n", pThis));
+ }
+}
+RT_EXPORT_SYMBOL(RTSpinlockRelease);
+