/**
* Internal worker for waking up the waiting thread.
*/
static void rtFileAioCtxWakeup(PRTFILEAIOCTXINTERNAL pCtxInt)
{
/*
* Read the thread handle before the status flag.
* If we read the handle after the flag we might
* end up with an invalid handle because the thread
* waiting in RTFileAioCtxWakeup() might get scheduled
* before we read the flag and returns.
* We can ensure that the handle is valid if fWaiting is true
* when reading the handle before the status flag.
*/
RTTHREAD hThread;
ASMAtomicReadHandle(&pCtxInt->hThreadWait, &hThread);
bool fWaiting = ASMAtomicReadBool(&pCtxInt->fWaiting);
if (fWaiting)
{
/*
* If a thread waits the handle must be valid.
* It is possible that the thread returns from
* aio_suspend() before the signal is send.
* This is no problem because we already set fWokenUp
* to true which will let the thread return VERR_INTERRUPTED
* and the next call to RTFileAioCtxWait() will not
* return VERR_INTERRUPTED because signals are not saved
* and will simply vanish if the destination thread can't
* receive it.
*/
Assert(hThread != NIL_RTTHREAD);
RTThreadPoke(hThread);
}
}
/**
* Resolves the address space handle into a real handle if it's an alias.
*
* @returns Real address space handle. NIL_RTDBGAS if invalid handle.
*
* @param pUVM The user mode VM handle.
* @param hAlias The possibly address space alias.
*
* @remarks Doesn't take any locks.
*/
VMMR3DECL(RTDBGAS) DBGFR3AsResolve(PUVM pUVM, RTDBGAS hAlias)
{
UVM_ASSERT_VALID_EXT_RETURN(pUVM, NULL);
AssertCompileNS(NIL_RTDBGAS == (RTDBGAS)0);
uintptr_t iAlias = DBGF_AS_ALIAS_2_INDEX(hAlias);
if (iAlias < DBGF_AS_COUNT)
ASMAtomicReadHandle(&pUVM->dbgf.s.ahAsAliases[iAlias], &hAlias);
return hAlias;
}
RTDECL(bool) RTSemMutexIsOwned(RTSEMMUTEX hMutexSem)
{
/*
* Validate.
*/
RTSEMMUTEXINTERNAL *pThis = hMutexSem;
AssertPtrReturn(pThis, false);
AssertReturn(pThis->u32Magic == RTSEMMUTEX_MAGIC, false);
RTNATIVETHREAD hNativeOwner;
ASMAtomicReadHandle(&pThis->hNativeOwner, &hNativeOwner);
return hNativeOwner != NIL_RTNATIVETHREAD;
}
RTDECL(int) RTSemMutexRelease(RTSEMMUTEX hMutexSem)
{
/*
* Validate.
*/
RTSEMMUTEXINTERNAL *pThis = hMutexSem;
AssertPtrReturn(pThis, VERR_INVALID_HANDLE);
AssertReturn(pThis->u32Magic == RTSEMMUTEX_MAGIC, VERR_INVALID_HANDLE);
/*
* Check ownership and recursions.
*/
RTNATIVETHREAD hNativeSelf = RTThreadNativeSelf();
RTNATIVETHREAD hNativeOwner;
ASMAtomicReadHandle(&pThis->hNativeOwner, &hNativeOwner);
if (RT_UNLIKELY(hNativeOwner != hNativeSelf))
{
AssertMsgFailed(("Not owner of mutex %p!! hNativeSelf=%RTntrd Owner=%RTntrd cRecursions=%d\n",
pThis, hNativeSelf, hNativeOwner, pThis->cRecursions));
return VERR_NOT_OWNER;
}
if (pThis->cRecursions > 1)
{
#ifdef RTSEMMUTEX_STRICT
int rc9 = RTLockValidatorRecExclUnwind(&pThis->ValidatorRec);
if (RT_FAILURE(rc9))
return rc9;
#endif
ASMAtomicDecU32(&pThis->cRecursions);
return VINF_SUCCESS;
}
/*
* Unlock mutex semaphore.
*/
#ifdef RTSEMMUTEX_STRICT
int rc9 = RTLockValidatorRecExclReleaseOwner(&pThis->ValidatorRec, false);
if (RT_FAILURE(rc9))
return rc9;
#endif
ASMAtomicWriteU32(&pThis->cRecursions, 0);
ASMAtomicWriteHandle(&pThis->hNativeOwner, NIL_RTNATIVETHREAD);
if (ReleaseMutex(pThis->hMtx))
return VINF_SUCCESS;
int rc = RTErrConvertFromWin32(GetLastError());
AssertMsgFailed(("%p/%p, rc=%Rrc lasterr=%d\n", pThis, pThis->hMtx, rc, GetLastError()));
return rc;
}
RTDECL(int) RTFileAioCtxWakeup(RTFILEAIOCTX hAioCtx)
{
PRTFILEAIOCTXINTERNAL pCtxInt = hAioCtx;
RTFILEAIOCTX_VALID_RETURN(pCtxInt);
/** @todo r=bird: Define the protocol for how to resume work after calling
* this function. */
bool fWokenUp = ASMAtomicXchgBool(&pCtxInt->fWokenUp, true);
/*
* Read the thread handle before the status flag.
* If we read the handle after the flag we might
* end up with an invalid handle because the thread
* waiting in RTFileAioCtxWakeup() might get scheduled
* before we read the flag and returns.
* We can ensure that the handle is valid if fWaiting is true
* when reading the handle before the status flag.
*/
RTTHREAD hThread;
ASMAtomicReadHandle(&pCtxInt->hThreadWait, &hThread);
bool fWaiting = ASMAtomicReadBool(&pCtxInt->fWaiting);
if ( !fWokenUp
&& fWaiting)
{
/*
* If a thread waits the handle must be valid.
* It is possible that the thread returns from
* rtFileAsyncIoLinuxGetEvents() before the signal
* is send.
* This is no problem because we already set fWokenUp
* to true which will let the thread return VERR_INTERRUPTED
* and the next call to RTFileAioCtxWait() will not
* return VERR_INTERRUPTED because signals are not saved
* and will simply vanish if the destination thread can't
* receive it.
*/
Assert(hThread != NIL_RTTHREAD);
RTThreadPoke(hThread);
}
return VINF_SUCCESS;
}
/**
* Internal worker for RTSemMutexRequestNoResume and it's debug companion.
*
* @returns Same as RTSEmMutexRequestNoResume
* @param hMutexSem The mutex handle.
* @param cMillies The number of milliseconds to wait.
* @param pSrcPos The source position of the caller.
*/
DECL_FORCE_INLINE(int) rtSemMutexRequestNoResume(RTSEMMUTEX hMutexSem, RTMSINTERVAL cMillies, PCRTLOCKVALSRCPOS pSrcPos)
{
/*
* Validate.
*/
RTSEMMUTEXINTERNAL *pThis = hMutexSem;
AssertPtrReturn(pThis, VERR_INVALID_HANDLE);
AssertReturn(pThis->u32Magic == RTSEMMUTEX_MAGIC, VERR_INVALID_HANDLE);
/*
* Check for recursive entry.
*/
RTNATIVETHREAD hNativeSelf = RTThreadNativeSelf();
RTNATIVETHREAD hNativeOwner;
ASMAtomicReadHandle(&pThis->hNativeOwner, &hNativeOwner);
if (hNativeOwner == hNativeSelf)
{
#ifdef RTSEMMUTEX_STRICT
int rc9 = RTLockValidatorRecExclRecursion(&pThis->ValidatorRec, pSrcPos);
if (RT_FAILURE(rc9))
return rc9;
#endif
ASMAtomicIncU32(&pThis->cRecursions);
return VINF_SUCCESS;
}
/*
* Lock mutex semaphore.
*/
RTTHREAD hThreadSelf = NIL_RTTHREAD;
if (cMillies > 0)
{
#ifdef RTSEMMUTEX_STRICT
hThreadSelf = RTThreadSelfAutoAdopt();
int rc9 = RTLockValidatorRecExclCheckOrderAndBlocking(&pThis->ValidatorRec, hThreadSelf, pSrcPos, true,
cMillies, RTTHREADSTATE_MUTEX, true);
if (RT_FAILURE(rc9))
return rc9;
#else
hThreadSelf = RTThreadSelf();
RTThreadBlocking(hThreadSelf, RTTHREADSTATE_MUTEX, true);
#endif
}
DWORD rc = WaitForSingleObjectEx(pThis->hMtx,
cMillies == RT_INDEFINITE_WAIT ? INFINITE : cMillies,
TRUE /*fAlertable*/);
RTThreadUnblocked(hThreadSelf, RTTHREADSTATE_MUTEX);
switch (rc)
{
case WAIT_OBJECT_0:
#ifdef RTSEMMUTEX_STRICT
RTLockValidatorRecExclSetOwner(&pThis->ValidatorRec, hThreadSelf, pSrcPos, true);
#endif
ASMAtomicWriteHandle(&pThis->hNativeOwner, hNativeSelf);
ASMAtomicWriteU32(&pThis->cRecursions, 1);
return VINF_SUCCESS;
case WAIT_TIMEOUT: return VERR_TIMEOUT;
case WAIT_IO_COMPLETION: return VERR_INTERRUPTED;
case WAIT_ABANDONED: return VERR_SEM_OWNER_DIED;
default:
AssertMsgFailed(("%u\n", rc));
case WAIT_FAILED:
{
int rc2 = RTErrConvertFromWin32(GetLastError());
AssertMsgFailed(("Wait on hMutexSem %p failed, rc=%d lasterr=%d\n", hMutexSem, rc, GetLastError()));
if (rc2 != VINF_SUCCESS)
return rc2;
AssertMsgFailed(("WaitForSingleObject(event) -> rc=%d while converted lasterr=%d\n", rc, rc2));
return VERR_INTERNAL_ERROR;
}
}
}
