Sweden-Number/scheduler/critsection.c

350 lines
9.8 KiB
C

/*
* Win32 critical sections
*
* Copyright 1998 Alexandre Julliard
*/
#include <assert.h>
#include <errno.h>
#include <stdio.h>
#include <sys/types.h>
#include "winerror.h"
#include "winbase.h"
#include "ntddk.h"
#include "heap.h"
#include "debugtools.h"
#include "thread.h"
DEFAULT_DEBUG_CHANNEL(win32);
DECLARE_DEBUG_CHANNEL(relay);
/***********************************************************************
* get_semaphore
*/
static inline HANDLE get_semaphore( CRITICAL_SECTION *crit )
{
HANDLE ret = crit->LockSemaphore;
if (!ret)
{
HANDLE sem = CreateSemaphoreA( NULL, 0, 1, NULL );
if (!(ret = (HANDLE)InterlockedCompareExchange( (PVOID *)&crit->LockSemaphore,
(PVOID)sem, 0 )))
ret = sem;
else
CloseHandle(sem); /* somebody beat us to it */
}
return ret;
}
/***********************************************************************
* InitializeCriticalSection (KERNEL32.472) (NTDLL.406)
*/
void WINAPI InitializeCriticalSection( CRITICAL_SECTION *crit )
{
crit->LockCount = -1;
crit->RecursionCount = 0;
crit->OwningThread = 0;
crit->LockSemaphore = 0;
}
/***********************************************************************
* DeleteCriticalSection (KERNEL32.185) (NTDLL.327)
*/
void WINAPI DeleteCriticalSection( CRITICAL_SECTION *crit )
{
if (crit->RecursionCount && crit->OwningThread != GetCurrentThreadId())
ERR("Deleting owned critical section (%p)\n", crit );
crit->LockCount = -1;
crit->RecursionCount = 0;
crit->OwningThread = 0;
if (crit->LockSemaphore) CloseHandle( crit->LockSemaphore );
crit->LockSemaphore = 0;
}
/***********************************************************************
* RtlpWaitForCriticalSection (NTDLL.@)
*/
void WINAPI RtlpWaitForCriticalSection( CRITICAL_SECTION *crit )
{
for (;;)
{
EXCEPTION_RECORD rec;
HANDLE sem = get_semaphore( crit );
DWORD res = WaitForSingleObject( sem, 5000L );
if ( res == WAIT_TIMEOUT )
{
ERR("Critical section %p wait timed out, retrying (60 sec)\n", crit );
res = WaitForSingleObject( sem, 60000L );
if ( res == WAIT_TIMEOUT && TRACE_ON(relay) )
{
ERR("Critical section %p wait timed out, retrying (5 min)\n", crit );
res = WaitForSingleObject( sem, 300000L );
}
}
if (res == STATUS_WAIT_0) break;
rec.ExceptionCode = EXCEPTION_CRITICAL_SECTION_WAIT;
rec.ExceptionFlags = 0;
rec.ExceptionRecord = NULL;
rec.ExceptionAddress = RtlRaiseException; /* sic */
rec.NumberParameters = 1;
rec.ExceptionInformation[0] = (DWORD)crit;
RtlRaiseException( &rec );
}
}
/***********************************************************************
* RtlpUnWaitCriticalSection (NTDLL.@)
*/
void WINAPI RtlpUnWaitCriticalSection( CRITICAL_SECTION *crit )
{
HANDLE sem = get_semaphore( crit );
ReleaseSemaphore( sem, 1, NULL );
}
/***********************************************************************
* EnterCriticalSection (KERNEL32.195) (NTDLL.344)
*/
void WINAPI EnterCriticalSection( CRITICAL_SECTION *crit )
{
if (InterlockedIncrement( &crit->LockCount ))
{
if (crit->OwningThread == GetCurrentThreadId())
{
crit->RecursionCount++;
return;
}
/* Now wait for it */
RtlpWaitForCriticalSection( crit );
}
crit->OwningThread = GetCurrentThreadId();
crit->RecursionCount = 1;
}
/***********************************************************************
* TryEnterCriticalSection (KERNEL32.898) (NTDLL.969)
*/
BOOL WINAPI TryEnterCriticalSection( CRITICAL_SECTION *crit )
{
BOOL ret = FALSE;
if (InterlockedCompareExchange( (PVOID *)&crit->LockCount,
(PVOID)0L, (PVOID)-1L ) == (PVOID)-1L)
{
crit->OwningThread = GetCurrentThreadId();
crit->RecursionCount = 1;
ret = TRUE;
}
else if (crit->OwningThread == GetCurrentThreadId())
{
InterlockedIncrement( &crit->LockCount );
crit->RecursionCount++;
ret = TRUE;
}
return ret;
}
/***********************************************************************
* LeaveCriticalSection (KERNEL32.494) (NTDLL.426)
*/
void WINAPI LeaveCriticalSection( CRITICAL_SECTION *crit )
{
if (crit->OwningThread != GetCurrentThreadId()) return;
if (--crit->RecursionCount)
{
InterlockedDecrement( &crit->LockCount );
return;
}
crit->OwningThread = 0;
if (InterlockedDecrement( &crit->LockCount ) >= 0)
{
/* Someone is waiting */
RtlpUnWaitCriticalSection( crit );
}
}
/***********************************************************************
* MakeCriticalSectionGlobal (KERNEL32.515)
*/
void WINAPI MakeCriticalSectionGlobal( CRITICAL_SECTION *crit )
{
crit->LockSemaphore = ConvertToGlobalHandle( get_semaphore( crit ) );
}
/***********************************************************************
* ReinitializeCriticalSection (KERNEL32.581)
*/
void WINAPI ReinitializeCriticalSection( CRITICAL_SECTION *crit )
{
if ( !crit->LockSemaphore )
InitializeCriticalSection( crit );
}
/***********************************************************************
* UninitializeCriticalSection (KERNEL32.703)
*/
void WINAPI UninitializeCriticalSection( CRITICAL_SECTION *crit )
{
DeleteCriticalSection( crit );
}
#ifdef __i386__
/***********************************************************************
* InterlockCompareExchange (KERNEL32.@)
*/
PVOID WINAPI InterlockedCompareExchange( PVOID *dest, PVOID xchg, PVOID compare );
__ASM_GLOBAL_FUNC(InterlockedCompareExchange,
"movl 12(%esp),%eax\n\t"
"movl 8(%esp),%ecx\n\t"
"movl 4(%esp),%edx\n\t"
"lock; cmpxchgl %ecx,(%edx)\n\t"
"ret $12");
/***********************************************************************
* InterlockedExchange (KERNEL32.@)
*/
LONG WINAPI InterlockedExchange( PLONG dest, LONG val );
__ASM_GLOBAL_FUNC(InterlockedExchange,
"movl 8(%esp),%eax\n\t"
"movl 4(%esp),%edx\n\t"
"lock; xchgl %eax,(%edx)\n\t"
"ret $8");
/***********************************************************************
* InterlockedExchangeAdd (KERNEL32.@)
*/
LONG WINAPI InterlockedExchangeAdd( PLONG dest, LONG incr );
__ASM_GLOBAL_FUNC(InterlockedExchangeAdd,
"movl 8(%esp),%eax\n\t"
"movl 4(%esp),%edx\n\t"
"lock; xaddl %eax,(%edx)\n\t"
"ret $8");
/***********************************************************************
* InterlockedIncrement (KERNEL32.@)
*/
LONG WINAPI InterlockedIncrement( PLONG dest );
__ASM_GLOBAL_FUNC(InterlockedIncrement,
"movl 4(%esp),%edx\n\t"
"movl $1,%eax\n\t"
"lock; xaddl %eax,(%edx)\n\t"
"incl %eax\n\t"
"ret $4");
/***********************************************************************
* InterlockDecrement (KERNEL32.@)
*/
LONG WINAPI InterlockedDecrement( PLONG dest );
__ASM_GLOBAL_FUNC(InterlockedDecrement,
"movl 4(%esp),%edx\n\t"
"movl $-1,%eax\n\t"
"lock; xaddl %eax,(%edx)\n\t"
"decl %eax\n\t"
"ret $4");
#elif defined(__sparc__) && defined(__sun__)
/*
* As the earlier Sparc processors lack necessary atomic instructions,
* I'm simply falling back to the library-provided _lwp_mutex routines
* to ensure mutual exclusion in a way appropriate for the current
* architecture.
*
* FIXME: If we have the compare-and-swap instruction (Sparc v9 and above)
* we could use this to speed up the Interlocked operations ...
*/
#include <synch.h>
static lwp_mutex_t interlocked_mutex = DEFAULTMUTEX;
/***********************************************************************
* InterlockedCompareExchange (KERNEL32.@)
*/
PVOID WINAPI InterlockedCompareExchange( PVOID *dest, PVOID xchg, PVOID compare )
{
_lwp_mutex_lock( &interlocked_mutex );
if ( *dest == compare )
*dest = xchg;
else
compare = *dest;
_lwp_mutex_unlock( &interlocked_mutex );
return compare;
}
/***********************************************************************
* InterlockedExchange (KERNEL32.@)
*/
LONG WINAPI InterlockedExchange( PLONG dest, LONG val )
{
LONG retv;
_lwp_mutex_lock( &interlocked_mutex );
retv = *dest;
*dest = val;
_lwp_mutex_unlock( &interlocked_mutex );
return retv;
}
/***********************************************************************
* InterlockedExchangeAdd (KERNEL32.@)
*/
LONG WINAPI InterlockedExchangeAdd( PLONG dest, LONG incr )
{
LONG retv;
_lwp_mutex_lock( &interlocked_mutex );
retv = *dest;
*dest += incr;
_lwp_mutex_unlock( &interlocked_mutex );
return retv;
}
/***********************************************************************
* InterlockedIncrement (KERNEL32.@)
*/
LONG WINAPI InterlockedIncrement( PLONG dest )
{
LONG retv;
_lwp_mutex_lock( &interlocked_mutex );
retv = ++*dest;
_lwp_mutex_unlock( &interlocked_mutex );
return retv;
}
/***********************************************************************
* InterlockedDecrement (KERNEL32.@)
*/
LONG WINAPI InterlockedDecrement( PLONG dest )
{
LONG retv;
_lwp_mutex_lock( &interlocked_mutex );
retv = --*dest;
_lwp_mutex_unlock( &interlocked_mutex );
return retv;
}
#else
#error You must implement the Interlocked* functions for your CPU
#endif