1ea5ca46c7
2. added some internal functions header for BaseLib 3. added EFIAPI for some internal assembly files declare git-svn-id: https://edk2.svn.sourceforge.net/svnroot/edk2/trunk/edk2@1050 6f19259b-4bc3-4df7-8a09-765794883524
103 lines
3.2 KiB
C
103 lines
3.2 KiB
C
/** @file
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Implementation of synchronization functions on Itanium.
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Copyright (c) 2006, Intel Corporation<BR>
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All rights reserved. This program and the accompanying materials
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are licensed and made available under the terms and conditions of the BSD License
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which accompanies this distribution. The full text of the license may be found at
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http://opensource.org/licenses/bsd-license.php
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THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,
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WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.
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Module Name: Synchronization.c
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**/
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/**
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Performs an atomic compare exchange operation on a 32-bit unsigned integer.
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Performs an atomic compare exchange operation on the 32-bit unsigned integer
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specified by Value. If Value is equal to CompareValue, then Value is set to
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ExchangeValue and CompareValue is returned. If Value is not equal to CompareValue,
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then Value is returned. The compare exchange operation must be performed using
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MP safe mechanisms.
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@param Value A pointer to the 32-bit value for the compare exchange
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operation.
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@param CompareValue 32-bit value used in compare operation.
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@param ExchangeValue 32-bit value used in exchange operation.
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@return The original *Value before exchange.
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**/
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UINT32
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EFIAPI
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InternalSyncCompareExchange32 (
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IN volatile UINT32 *Value,
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IN UINT32 CompareValue,
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IN UINT32 ExchangeValue
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);
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/**
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Performs an atomic increment of an 32-bit unsigned integer.
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Performs an atomic increment of the 32-bit unsigned integer specified by
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Value and returns the incremented value. The increment operation must be
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performed using MP safe mechanisms. The state of the return value is not
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guaranteed to be MP safe.
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@param Value A pointer to the 32-bit value to increment.
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@return The incremented value.
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**/
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UINT32
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EFIAPI
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InternalSyncIncrement (
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IN volatile UINT32 *Value
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)
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{
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UINT32 OriginalValue;
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do {
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OriginalValue = *Value;
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} while (OriginalValue != InternalSyncCompareExchange32 (
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Value,
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OriginalValue,
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OriginalValue + 1
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));
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return OriginalValue + 1;
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}
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/**
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Performs an atomic decrement of an 32-bit unsigned integer.
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Performs an atomic decrement of the 32-bit unsigned integer specified by
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Value and returns the decrement value. The decrement operation must be
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performed using MP safe mechanisms. The state of the return value is not
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guaranteed to be MP safe.
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@param Value A pointer to the 32-bit value to decrement.
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@return The decrement value.
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**/
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UINT32
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EFIAPI
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InternalSyncDecrement (
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IN volatile UINT32 *Value
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)
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{
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UINT32 OriginalValue;
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do {
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OriginalValue = *Value;
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} while (OriginalValue != InternalSyncCompareExchange32 (
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Value,
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OriginalValue,
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OriginalValue - 1
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));
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return OriginalValue - 1;
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}
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