MdePkg/Library/BaseLib/Ipf/Synchronization.c

   1 /** @file
   2   Implementation of synchronization functions on Itanium.
   3
   4   Copyright (c) 2006, Intel Corporation<BR>
   5   All rights reserved. This program and the accompanying materials
   6   are licensed and made available under the terms and conditions of the BSD License
   7   which accompanies this distribution.  The full text of the license may be found at
   8   http://opensource.org/licenses/bsd-license.php
   9
  10   THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,
  11   WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.
  12
  13   Module Name:  Synchronization.c
  14
  15 **/
  16
  17 UINT32
  18 EFIAPI
  19 InternalSyncCompareExchange32 (
  20   IN      volatile UINT32           *Value,
  21   IN      UINT32                    CompareValue,
  22   IN      UINT32                    ExchangeValue
  23   );
  24
  25 UINT32
  26 EFIAPI
  27 InternalSyncIncrement (
  28   IN      volatile UINT32           *Value
  29   )
  30 {
  31   UINT32                            OriginalValue;
  32
  33   do {
  34     OriginalValue = *Value;
  35   } while (OriginalValue == InternalSyncCompareExchange32 (
  36                               Value,
  37                               OriginalValue,
  38                               OriginalValue + 1
  39                               ));
  40   return OriginalValue + 1;
  41 }
  42
  43 UINT32
  44 EFIAPI
  45 InternalSyncDecrement (
  46   IN      volatile UINT32           *Value
  47   )
  48 {
  49   UINT32                            OriginalValue;
  50
  51   do {
  52     OriginalValue = *Value;
  53   } while (OriginalValue == InternalSyncCompareExchange32 (
  54                               Value,
  55                               OriginalValue,
  56                               OriginalValue - 1
  57                               ));
  58   return OriginalValue - 1;
  59 }