reactos/ntoskrnl/hal/x86/fmutex.c

   1 /* $Id: fmutex.c,v 1.1 2000/06/09 20:05:00 ekohl Exp $
   2  *
   3  * COPYRIGHT:       See COPYING in the top level directory
   4  * PROJECT:         ReactOS kernel
   5  * FILE:            ntoskrnl/hal/x86/fmutex.c
   6  * PURPOSE:         Implements fast mutexes
   7  * PROGRAMMER:      David Welch (welch@cwcom.net)
   8  *                  Eric Kohl (ekohl@rz-online.de)
   9  * UPDATE HISTORY:
  10  *                  Created 09/06/2000
  11  */
  12
  13 /* INCLUDES *****************************************************************/
  14
  15 #include <ddk/ntddk.h>
  16
  17 #include <internal/debug.h>
  18
  19 /* FUNCTIONS *****************************************************************/
  20
  21 VOID
  22 FASTCALL
  23 EXPORTED
  24 ExAcquireFastMutex (
  25         PFAST_MUTEX     FastMutex
  26         )
  27 {
  28    KeEnterCriticalRegion();
  29    if (InterlockedDecrement(&(FastMutex->Count))==0)
  30      {
  31         return;
  32      }
  33    FastMutex->Contention++;
  34    KeWaitForSingleObject(&(FastMutex->Event),
  35                          Executive,
  36                          KernelMode,
  37                          FALSE,
  38                          NULL);
  39    FastMutex->Owner=KeGetCurrentThread();
  40 }
  41
  42
  43 VOID
  44 FASTCALL
  45 EXPORTED
  46 ExReleaseFastMutex (
  47         PFAST_MUTEX     FastMutex
  48         )
  49 {
  50    assert(FastMutex->Owner == KeGetCurrentThread());
  51    FastMutex->Owner=NULL;
  52    if (InterlockedIncrement(&(FastMutex->Count))<=0)
  53      {
  54         return;
  55      }
  56    KeSetEvent(&(FastMutex->Event),0,FALSE);
  57
  58    KeLeaveCriticalRegion();
  59 }
  60
  61
  62 BOOLEAN
  63 FASTCALL
  64 EXPORTED
  65 ExTryToAcquireFastMutex (
  66         PFAST_MUTEX     FastMutex
  67         )
  68 {
  69    UNIMPLEMENTED;
  70 }
  71
  72 /* EOF */