Michael Kinney 4cee954ea8 MdePkg/BaseSynchronizationLib: Add volatile Interlocked*() APIs
The SpinLock functions in the SynchronicationLib use volatile
parameters to keep compiler from optimizing these functions
too much.  The volatile keyword is missing from the Interlocked*()
functions in this same library instance.  Update the library instance
to consistently use volatile on all functions in the
SynchronizationLib class.

Cc: Liming Gao <liming.gao@intel.com>
Cc: Laszlo Ersek <lersek@redhat.com>
Cc: Andrew Fish <afish@apple.com>
Cc: Jeff Fan <jeff.fan@intel.com>
Contributed-under: TianoCore Contribution Agreement 1.0
Signed-off-by: Michael Kinney <michael.d.kinney@intel.com>
Reviewed-by: Laszlo Ersek <lersek@redhat.com>
Reviewed-by: Liming Gao <liming.gao@intel.com>
2016-11-17 17:08:19 -08:00

47 lines
1.3 KiB
C

/** @file
InterlockedDecrement function
Copyright (c) 2006 - 2016, Intel Corporation. All rights reserved.<BR>
This program and the accompanying materials
are licensed and made available under the terms and conditions of the BSD License
which accompanies this distribution. The full text of the license may be found at
http://opensource.org/licenses/bsd-license.php.
THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,
WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.
**/
/**
Microsoft Visual Studio 7.1 Function Prototypes for I/O Intrinsics.
**/
long _InterlockedDecrement(
long * lpAddend
);
#pragma intrinsic(_InterlockedDecrement)
/**
Performs an atomic decrement of an 32-bit unsigned integer.
Performs an atomic decrement of the 32-bit unsigned integer specified by
Value and returns the decrement value. The decrement operation must be
performed using MP safe mechanisms. The state of the return value is not
guaranteed to be MP safe.
@param Value A pointer to the 32-bit value to decrement.
@return The decrement value.
**/
UINT32
EFIAPI
InternalSyncDecrement (
IN volatile UINT32 *Value
)
{
return _InterlockedDecrement ((long *)(UINTN)(Value));
}