1f1986470af9f0bb750dd859b142dc2e952deb20vboxsync/* $Id$ */
1f1986470af9f0bb750dd859b142dc2e952deb20vboxsync/** @file
5b281ba489ca18f0380d7efc7a5108b606cce449vboxsync * IPRT - Spinlocks, Ring-0 Driver, FreeBSD.
1f1986470af9f0bb750dd859b142dc2e952deb20vboxsync */
1f1986470af9f0bb750dd859b142dc2e952deb20vboxsync
1f1986470af9f0bb750dd859b142dc2e952deb20vboxsync/*
1f1986470af9f0bb750dd859b142dc2e952deb20vboxsync * Copyright (c) 2007 knut st. osmundsen <bird-src-spam@anduin.net>
1f1986470af9f0bb750dd859b142dc2e952deb20vboxsync *
1f1986470af9f0bb750dd859b142dc2e952deb20vboxsync * Permission is hereby granted, free of charge, to any person
1f1986470af9f0bb750dd859b142dc2e952deb20vboxsync * obtaining a copy of this software and associated documentation
1f1986470af9f0bb750dd859b142dc2e952deb20vboxsync * files (the "Software"), to deal in the Software without
1f1986470af9f0bb750dd859b142dc2e952deb20vboxsync * restriction, including without limitation the rights to use,
1f1986470af9f0bb750dd859b142dc2e952deb20vboxsync * copy, modify, merge, publish, distribute, sublicense, and/or sell
1f1986470af9f0bb750dd859b142dc2e952deb20vboxsync * copies of the Software, and to permit persons to whom the
1f1986470af9f0bb750dd859b142dc2e952deb20vboxsync * Software is furnished to do so, subject to the following
1f1986470af9f0bb750dd859b142dc2e952deb20vboxsync * conditions:
1f1986470af9f0bb750dd859b142dc2e952deb20vboxsync *
1f1986470af9f0bb750dd859b142dc2e952deb20vboxsync * The above copyright notice and this permission notice shall be
1f1986470af9f0bb750dd859b142dc2e952deb20vboxsync * included in all copies or substantial portions of the Software.
1f1986470af9f0bb750dd859b142dc2e952deb20vboxsync *
1f1986470af9f0bb750dd859b142dc2e952deb20vboxsync * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
1f1986470af9f0bb750dd859b142dc2e952deb20vboxsync * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES
1f1986470af9f0bb750dd859b142dc2e952deb20vboxsync * OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
1f1986470af9f0bb750dd859b142dc2e952deb20vboxsync * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT
1f1986470af9f0bb750dd859b142dc2e952deb20vboxsync * HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY,
1f1986470af9f0bb750dd859b142dc2e952deb20vboxsync * WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
1f1986470af9f0bb750dd859b142dc2e952deb20vboxsync * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
1f1986470af9f0bb750dd859b142dc2e952deb20vboxsync * OTHER DEALINGS IN THE SOFTWARE.
1f1986470af9f0bb750dd859b142dc2e952deb20vboxsync */
1f1986470af9f0bb750dd859b142dc2e952deb20vboxsync
1f1986470af9f0bb750dd859b142dc2e952deb20vboxsync/*******************************************************************************
1f1986470af9f0bb750dd859b142dc2e952deb20vboxsync* Header Files *
1f1986470af9f0bb750dd859b142dc2e952deb20vboxsync*******************************************************************************/
1f1986470af9f0bb750dd859b142dc2e952deb20vboxsync#include "the-freebsd-kernel.h"
3619a23ecce9ab8cdbf52dc55d9c7ff6e8ad7ccavboxsync#include "internal/iprt.h"
1f1986470af9f0bb750dd859b142dc2e952deb20vboxsync
1f1986470af9f0bb750dd859b142dc2e952deb20vboxsync#include <iprt/spinlock.h>
1f1986470af9f0bb750dd859b142dc2e952deb20vboxsync#include <iprt/err.h>
1f1986470af9f0bb750dd859b142dc2e952deb20vboxsync#include <iprt/alloc.h>
1f1986470af9f0bb750dd859b142dc2e952deb20vboxsync#include <iprt/assert.h>
1f1986470af9f0bb750dd859b142dc2e952deb20vboxsync#include <iprt/asm.h>
f737cdef9a611a3ebe4cfd6da04c42ede272344cvboxsync#include <iprt/asm-amd64-x86.h>
3619a23ecce9ab8cdbf52dc55d9c7ff6e8ad7ccavboxsync#include <iprt/thread.h>
3619a23ecce9ab8cdbf52dc55d9c7ff6e8ad7ccavboxsync#include <iprt/mp.h>
1f1986470af9f0bb750dd859b142dc2e952deb20vboxsync
1f1986470af9f0bb750dd859b142dc2e952deb20vboxsync#include "internal/magics.h"
1f1986470af9f0bb750dd859b142dc2e952deb20vboxsync
1f1986470af9f0bb750dd859b142dc2e952deb20vboxsync
1f1986470af9f0bb750dd859b142dc2e952deb20vboxsync/*******************************************************************************
1f1986470af9f0bb750dd859b142dc2e952deb20vboxsync* Structures and Typedefs *
1f1986470af9f0bb750dd859b142dc2e952deb20vboxsync*******************************************************************************/
1f1986470af9f0bb750dd859b142dc2e952deb20vboxsync/**
1f1986470af9f0bb750dd859b142dc2e952deb20vboxsync * Wrapper for the struct mtx type.
1f1986470af9f0bb750dd859b142dc2e952deb20vboxsync */
1f1986470af9f0bb750dd859b142dc2e952deb20vboxsynctypedef struct RTSPINLOCKINTERNAL
1f1986470af9f0bb750dd859b142dc2e952deb20vboxsync{
1f1986470af9f0bb750dd859b142dc2e952deb20vboxsync /** Spinlock magic value (RTSPINLOCK_MAGIC). */
1f1986470af9f0bb750dd859b142dc2e952deb20vboxsync uint32_t volatile u32Magic;
3619a23ecce9ab8cdbf52dc55d9c7ff6e8ad7ccavboxsync /** The spinlock. */
3619a23ecce9ab8cdbf52dc55d9c7ff6e8ad7ccavboxsync uint32_t volatile fLocked;
f0ed7ab5e7f8d2f73b5aa08e46eb3a04cbb31cb2vboxsync /** Saved interrupt flag. */
f0ed7ab5e7f8d2f73b5aa08e46eb3a04cbb31cb2vboxsync uint32_t volatile fIntSaved;
f0ed7ab5e7f8d2f73b5aa08e46eb3a04cbb31cb2vboxsync /** The spinlock creation flags. */
f0ed7ab5e7f8d2f73b5aa08e46eb3a04cbb31cb2vboxsync uint32_t fFlags;
3619a23ecce9ab8cdbf52dc55d9c7ff6e8ad7ccavboxsync#ifdef RT_MORE_STRICT
3619a23ecce9ab8cdbf52dc55d9c7ff6e8ad7ccavboxsync /** The idAssertCpu variable before acquring the lock for asserting after
3619a23ecce9ab8cdbf52dc55d9c7ff6e8ad7ccavboxsync * releasing the spinlock. */
3619a23ecce9ab8cdbf52dc55d9c7ff6e8ad7ccavboxsync RTCPUID volatile idAssertCpu;
3619a23ecce9ab8cdbf52dc55d9c7ff6e8ad7ccavboxsync /** The CPU that owns the lock. */
3619a23ecce9ab8cdbf52dc55d9c7ff6e8ad7ccavboxsync RTCPUID volatile idCpuOwner;
3619a23ecce9ab8cdbf52dc55d9c7ff6e8ad7ccavboxsync#endif
1f1986470af9f0bb750dd859b142dc2e952deb20vboxsync} RTSPINLOCKINTERNAL, *PRTSPINLOCKINTERNAL;
1f1986470af9f0bb750dd859b142dc2e952deb20vboxsync
1f1986470af9f0bb750dd859b142dc2e952deb20vboxsync
f0ed7ab5e7f8d2f73b5aa08e46eb3a04cbb31cb2vboxsyncRTDECL(int) RTSpinlockCreate(PRTSPINLOCK pSpinlock, uint32_t fFlags, const char *pszName)
1f1986470af9f0bb750dd859b142dc2e952deb20vboxsync{
f0ed7ab5e7f8d2f73b5aa08e46eb3a04cbb31cb2vboxsync RT_ASSERT_PREEMPTIBLE();
f0ed7ab5e7f8d2f73b5aa08e46eb3a04cbb31cb2vboxsync AssertReturn(fFlags == RTSPINLOCK_FLAGS_INTERRUPT_SAFE || fFlags == RTSPINLOCK_FLAGS_INTERRUPT_UNSAFE, VERR_INVALID_PARAMETER);
f0ed7ab5e7f8d2f73b5aa08e46eb3a04cbb31cb2vboxsync
1f1986470af9f0bb750dd859b142dc2e952deb20vboxsync /*
1f1986470af9f0bb750dd859b142dc2e952deb20vboxsync * Allocate.
1f1986470af9f0bb750dd859b142dc2e952deb20vboxsync */
1f1986470af9f0bb750dd859b142dc2e952deb20vboxsync AssertCompile(sizeof(RTSPINLOCKINTERNAL) > sizeof(void *));
fb27046b613e2b74e6e39910bd69bf35bd344652vboxsync PRTSPINLOCKINTERNAL pThis = (PRTSPINLOCKINTERNAL)RTMemAllocZ(sizeof(*pThis));
fb27046b613e2b74e6e39910bd69bf35bd344652vboxsync if (!pThis)
1f1986470af9f0bb750dd859b142dc2e952deb20vboxsync return VERR_NO_MEMORY;
1f1986470af9f0bb750dd859b142dc2e952deb20vboxsync
1f1986470af9f0bb750dd859b142dc2e952deb20vboxsync /*
1f1986470af9f0bb750dd859b142dc2e952deb20vboxsync * Initialize & return.
1f1986470af9f0bb750dd859b142dc2e952deb20vboxsync */
f0ed7ab5e7f8d2f73b5aa08e46eb3a04cbb31cb2vboxsync pThis->u32Magic = RTSPINLOCK_MAGIC;
f0ed7ab5e7f8d2f73b5aa08e46eb3a04cbb31cb2vboxsync pThis->fLocked = 0;
f0ed7ab5e7f8d2f73b5aa08e46eb3a04cbb31cb2vboxsync pThis->fFlags = fFlags;
f0ed7ab5e7f8d2f73b5aa08e46eb3a04cbb31cb2vboxsync pThis->fIntSaved = 0;
f0ed7ab5e7f8d2f73b5aa08e46eb3a04cbb31cb2vboxsync
fb27046b613e2b74e6e39910bd69bf35bd344652vboxsync *pSpinlock = pThis;
1f1986470af9f0bb750dd859b142dc2e952deb20vboxsync return VINF_SUCCESS;
1f1986470af9f0bb750dd859b142dc2e952deb20vboxsync}
1f1986470af9f0bb750dd859b142dc2e952deb20vboxsync
1f1986470af9f0bb750dd859b142dc2e952deb20vboxsync
1f1986470af9f0bb750dd859b142dc2e952deb20vboxsyncRTDECL(int) RTSpinlockDestroy(RTSPINLOCK Spinlock)
1f1986470af9f0bb750dd859b142dc2e952deb20vboxsync{
1f1986470af9f0bb750dd859b142dc2e952deb20vboxsync /*
1f1986470af9f0bb750dd859b142dc2e952deb20vboxsync * Validate input.
1f1986470af9f0bb750dd859b142dc2e952deb20vboxsync */
3619a23ecce9ab8cdbf52dc55d9c7ff6e8ad7ccavboxsync RT_ASSERT_INTS_ON();
fb27046b613e2b74e6e39910bd69bf35bd344652vboxsync PRTSPINLOCKINTERNAL pThis = (PRTSPINLOCKINTERNAL)Spinlock;
fb27046b613e2b74e6e39910bd69bf35bd344652vboxsync if (!pThis)
1f1986470af9f0bb750dd859b142dc2e952deb20vboxsync return VERR_INVALID_PARAMETER;
fb27046b613e2b74e6e39910bd69bf35bd344652vboxsync AssertMsgReturn(pThis->u32Magic == RTSPINLOCK_MAGIC,
fb27046b613e2b74e6e39910bd69bf35bd344652vboxsync ("Invalid spinlock %p magic=%#x\n", pThis, pThis->u32Magic),
1f1986470af9f0bb750dd859b142dc2e952deb20vboxsync VERR_INVALID_PARAMETER);
1f1986470af9f0bb750dd859b142dc2e952deb20vboxsync
1f1986470af9f0bb750dd859b142dc2e952deb20vboxsync /*
1f1986470af9f0bb750dd859b142dc2e952deb20vboxsync * Make the lock invalid and release the memory.
1f1986470af9f0bb750dd859b142dc2e952deb20vboxsync */
fb27046b613e2b74e6e39910bd69bf35bd344652vboxsync ASMAtomicIncU32(&pThis->u32Magic);
fb27046b613e2b74e6e39910bd69bf35bd344652vboxsync RTMemFree(pThis);
1f1986470af9f0bb750dd859b142dc2e952deb20vboxsync return VINF_SUCCESS;
1f1986470af9f0bb750dd859b142dc2e952deb20vboxsync}
1f1986470af9f0bb750dd859b142dc2e952deb20vboxsync
1f1986470af9f0bb750dd859b142dc2e952deb20vboxsync
f0ed7ab5e7f8d2f73b5aa08e46eb3a04cbb31cb2vboxsyncRTDECL(void) RTSpinlockAcquire(RTSPINLOCK Spinlock)
1f1986470af9f0bb750dd859b142dc2e952deb20vboxsync{
fb27046b613e2b74e6e39910bd69bf35bd344652vboxsync PRTSPINLOCKINTERNAL pThis = (PRTSPINLOCKINTERNAL)Spinlock;
f0ed7ab5e7f8d2f73b5aa08e46eb3a04cbb31cb2vboxsync RT_ASSERT_PREEMPT_CPUID_VAR();
fb27046b613e2b74e6e39910bd69bf35bd344652vboxsync AssertPtr(pThis);
fb27046b613e2b74e6e39910bd69bf35bd344652vboxsync Assert(pThis->u32Magic == RTSPINLOCK_MAGIC);
3619a23ecce9ab8cdbf52dc55d9c7ff6e8ad7ccavboxsync
f0ed7ab5e7f8d2f73b5aa08e46eb3a04cbb31cb2vboxsync if (pThis->fFlags & RTSPINLOCK_FLAGS_INTERRUPT_SAFE)
3619a23ecce9ab8cdbf52dc55d9c7ff6e8ad7ccavboxsync {
fb27046b613e2b74e6e39910bd69bf35bd344652vboxsync for (;;)
fb27046b613e2b74e6e39910bd69bf35bd344652vboxsync {
f0ed7ab5e7f8d2f73b5aa08e46eb3a04cbb31cb2vboxsync uint32_t fIntSaved = ASMIntDisableFlags();
f0ed7ab5e7f8d2f73b5aa08e46eb3a04cbb31cb2vboxsync critical_enter();
f0ed7ab5e7f8d2f73b5aa08e46eb3a04cbb31cb2vboxsync
f0ed7ab5e7f8d2f73b5aa08e46eb3a04cbb31cb2vboxsync int c = 50;
f0ed7ab5e7f8d2f73b5aa08e46eb3a04cbb31cb2vboxsync for (;;)
3619a23ecce9ab8cdbf52dc55d9c7ff6e8ad7ccavboxsync {
f0ed7ab5e7f8d2f73b5aa08e46eb3a04cbb31cb2vboxsync if (ASMAtomicCmpXchgU32(&pThis->fLocked, 1, 0))
f0ed7ab5e7f8d2f73b5aa08e46eb3a04cbb31cb2vboxsync {
f0ed7ab5e7f8d2f73b5aa08e46eb3a04cbb31cb2vboxsync RT_ASSERT_PREEMPT_CPUID_SPIN_ACQUIRED(pThis);
f0ed7ab5e7f8d2f73b5aa08e46eb3a04cbb31cb2vboxsync pThis->fIntSaved = fIntSaved;
f0ed7ab5e7f8d2f73b5aa08e46eb3a04cbb31cb2vboxsync return;
f0ed7ab5e7f8d2f73b5aa08e46eb3a04cbb31cb2vboxsync }
f0ed7ab5e7f8d2f73b5aa08e46eb3a04cbb31cb2vboxsync if (--c <= 0)
f0ed7ab5e7f8d2f73b5aa08e46eb3a04cbb31cb2vboxsync break;
f0ed7ab5e7f8d2f73b5aa08e46eb3a04cbb31cb2vboxsync cpu_spinwait();
3619a23ecce9ab8cdbf52dc55d9c7ff6e8ad7ccavboxsync }
3619a23ecce9ab8cdbf52dc55d9c7ff6e8ad7ccavboxsync
f0ed7ab5e7f8d2f73b5aa08e46eb3a04cbb31cb2vboxsync /* Enable interrupts while we sleep. */
f0ed7ab5e7f8d2f73b5aa08e46eb3a04cbb31cb2vboxsync ASMSetFlags(fIntSaved);
07ce17b51374f83a935f97f1041f38b174d8aa47vboxsync critical_exit();
f0ed7ab5e7f8d2f73b5aa08e46eb3a04cbb31cb2vboxsync DELAY(1);
f0ed7ab5e7f8d2f73b5aa08e46eb3a04cbb31cb2vboxsync }
3619a23ecce9ab8cdbf52dc55d9c7ff6e8ad7ccavboxsync }
f0ed7ab5e7f8d2f73b5aa08e46eb3a04cbb31cb2vboxsync else
3619a23ecce9ab8cdbf52dc55d9c7ff6e8ad7ccavboxsync {
fb27046b613e2b74e6e39910bd69bf35bd344652vboxsync for (;;)
fb27046b613e2b74e6e39910bd69bf35bd344652vboxsync {
f0ed7ab5e7f8d2f73b5aa08e46eb3a04cbb31cb2vboxsync critical_enter();
f0ed7ab5e7f8d2f73b5aa08e46eb3a04cbb31cb2vboxsync
f0ed7ab5e7f8d2f73b5aa08e46eb3a04cbb31cb2vboxsync int c = 50;
f0ed7ab5e7f8d2f73b5aa08e46eb3a04cbb31cb2vboxsync for (;;)
3619a23ecce9ab8cdbf52dc55d9c7ff6e8ad7ccavboxsync {
f0ed7ab5e7f8d2f73b5aa08e46eb3a04cbb31cb2vboxsync if (ASMAtomicCmpXchgU32(&pThis->fLocked, 1, 0))
f0ed7ab5e7f8d2f73b5aa08e46eb3a04cbb31cb2vboxsync {
f0ed7ab5e7f8d2f73b5aa08e46eb3a04cbb31cb2vboxsync RT_ASSERT_PREEMPT_CPUID_SPIN_ACQUIRED(pThis);
f0ed7ab5e7f8d2f73b5aa08e46eb3a04cbb31cb2vboxsync return;
f0ed7ab5e7f8d2f73b5aa08e46eb3a04cbb31cb2vboxsync }
f0ed7ab5e7f8d2f73b5aa08e46eb3a04cbb31cb2vboxsync if (--c <= 0)
f0ed7ab5e7f8d2f73b5aa08e46eb3a04cbb31cb2vboxsync break;
f0ed7ab5e7f8d2f73b5aa08e46eb3a04cbb31cb2vboxsync cpu_spinwait();
3619a23ecce9ab8cdbf52dc55d9c7ff6e8ad7ccavboxsync }
3619a23ecce9ab8cdbf52dc55d9c7ff6e8ad7ccavboxsync
f0ed7ab5e7f8d2f73b5aa08e46eb3a04cbb31cb2vboxsync critical_exit();
f0ed7ab5e7f8d2f73b5aa08e46eb3a04cbb31cb2vboxsync DELAY(1);
f0ed7ab5e7f8d2f73b5aa08e46eb3a04cbb31cb2vboxsync }
3619a23ecce9ab8cdbf52dc55d9c7ff6e8ad7ccavboxsync }
1f1986470af9f0bb750dd859b142dc2e952deb20vboxsync}
1f1986470af9f0bb750dd859b142dc2e952deb20vboxsync
1f1986470af9f0bb750dd859b142dc2e952deb20vboxsync
f0ed7ab5e7f8d2f73b5aa08e46eb3a04cbb31cb2vboxsyncRTDECL(void) RTSpinlockRelease(RTSPINLOCK Spinlock)
1f1986470af9f0bb750dd859b142dc2e952deb20vboxsync{
fb27046b613e2b74e6e39910bd69bf35bd344652vboxsync PRTSPINLOCKINTERNAL pThis = (PRTSPINLOCKINTERNAL)Spinlock;
3619a23ecce9ab8cdbf52dc55d9c7ff6e8ad7ccavboxsync RT_ASSERT_PREEMPT_CPUID_SPIN_RELEASE_VARS();
3619a23ecce9ab8cdbf52dc55d9c7ff6e8ad7ccavboxsync
fb27046b613e2b74e6e39910bd69bf35bd344652vboxsync AssertPtr(pThis);
fb27046b613e2b74e6e39910bd69bf35bd344652vboxsync Assert(pThis->u32Magic == RTSPINLOCK_MAGIC);
fb27046b613e2b74e6e39910bd69bf35bd344652vboxsync RT_ASSERT_PREEMPT_CPUID_SPIN_RELEASE(pThis);
1f1986470af9f0bb750dd859b142dc2e952deb20vboxsync
f0ed7ab5e7f8d2f73b5aa08e46eb3a04cbb31cb2vboxsync if (pThis->fFlags & RTSPINLOCK_FLAGS_INTERRUPT_SAFE)
f0ed7ab5e7f8d2f73b5aa08e46eb3a04cbb31cb2vboxsync {
f0ed7ab5e7f8d2f73b5aa08e46eb3a04cbb31cb2vboxsync uint32_t fIntSaved = pThis->fIntSaved;
f0ed7ab5e7f8d2f73b5aa08e46eb3a04cbb31cb2vboxsync pThis->fIntSaved = 0;
f0ed7ab5e7f8d2f73b5aa08e46eb3a04cbb31cb2vboxsync if (ASMAtomicCmpXchgU32(&pThis->fLocked, 0, 1))
07ce17b51374f83a935f97f1041f38b174d8aa47vboxsync ASMSetFlags(fIntSaved);
f0ed7ab5e7f8d2f73b5aa08e46eb3a04cbb31cb2vboxsync else
f0ed7ab5e7f8d2f73b5aa08e46eb3a04cbb31cb2vboxsync AssertMsgFailed(("Spinlock %p was not locked!\n", pThis));
f0ed7ab5e7f8d2f73b5aa08e46eb3a04cbb31cb2vboxsync }
f0ed7ab5e7f8d2f73b5aa08e46eb3a04cbb31cb2vboxsync else
f0ed7ab5e7f8d2f73b5aa08e46eb3a04cbb31cb2vboxsync {
f0ed7ab5e7f8d2f73b5aa08e46eb3a04cbb31cb2vboxsync if (!ASMAtomicCmpXchgU32(&pThis->fLocked, 0, 1))
f0ed7ab5e7f8d2f73b5aa08e46eb3a04cbb31cb2vboxsync AssertMsgFailed(("Spinlock %p was not locked!\n", pThis));
f0ed7ab5e7f8d2f73b5aa08e46eb3a04cbb31cb2vboxsync }
3619a23ecce9ab8cdbf52dc55d9c7ff6e8ad7ccavboxsync
3619a23ecce9ab8cdbf52dc55d9c7ff6e8ad7ccavboxsync critical_exit();
1f1986470af9f0bb750dd859b142dc2e952deb20vboxsync}
1f1986470af9f0bb750dd859b142dc2e952deb20vboxsync