#include "BaseSynchronizationLibInternals.h"

Macros
#define	SPIN_LOCK_RELEASED ((UINTN) 1)

#define	SPIN_LOCK_ACQUIRED ((UINTN) 2)

Functions
UINTN EFIAPI	GetSpinLockProperties (VOID)

SPIN_LOCK *EFIAPI	InitializeSpinLock (OUT SPIN_LOCK *SpinLock)

SPIN_LOCK *EFIAPI	AcquireSpinLock (IN OUT SPIN_LOCK *SpinLock)

BOOLEAN EFIAPI	AcquireSpinLockOrFail (IN OUT SPIN_LOCK *SpinLock)

SPIN_LOCK *EFIAPI	ReleaseSpinLock (IN OUT SPIN_LOCK *SpinLock)

UINT32 EFIAPI	InterlockedIncrement (IN volatile UINT32 *Value)

UINT32 EFIAPI	InterlockedDecrement (IN volatile UINT32 *Value)

UINT16 EFIAPI	InterlockedCompareExchange16 (IN OUT volatile UINT16 *Value, IN UINT16 CompareValue, IN UINT16 ExchangeValue)

UINT32 EFIAPI	InterlockedCompareExchange32 (IN OUT volatile UINT32 *Value, IN UINT32 CompareValue, IN UINT32 ExchangeValue)

UINT64 EFIAPI	InterlockedCompareExchange64 (IN OUT volatile UINT64 *Value, IN UINT64 CompareValue, IN UINT64 ExchangeValue)

VOID *EFIAPI	InterlockedCompareExchangePointer (IN OUT VOID volatile Value, IN VOID CompareValue, IN VOID ExchangeValue)

Detailed Description

Implementation of synchronization functions.

Copyright (c) 2006 - 2018, Intel Corporation. All rights reserved.
SPDX-License-Identifier: BSD-2-Clause-Patent

Definition in file Synchronization.c.

Macro Definition Documentation

◆ SPIN_LOCK_ACQUIRED

#define SPIN_LOCK_ACQUIRED ((UINTN) 2)

Definition at line 12 of file Synchronization.c.

◆ SPIN_LOCK_RELEASED

#define SPIN_LOCK_RELEASED ((UINTN) 1)

Definition at line 11 of file Synchronization.c.

Function Documentation

◆ AcquireSpinLock()

SPIN_LOCK *EFIAPI AcquireSpinLock ( IN OUT SPIN_LOCK * SpinLock )

Waits until a spin lock can be placed in the acquired state.

This function checks the state of the spin lock specified by SpinLock. If SpinLock is in the released state, then this function places SpinLock in the acquired state and returns SpinLock. Otherwise, this function waits indefinitely for the spin lock to be released, and then places it in the acquired state and returns SpinLock. All state transitions of SpinLock must be performed using MP safe mechanisms.

If SpinLock is NULL, then ASSERT(). If SpinLock was not initialized with InitializeSpinLock(), then ASSERT(). If PcdSpinLockTimeout is not zero, and SpinLock is can not be acquired in PcdSpinLockTimeout microseconds, then ASSERT().

Parameters

SpinLock A pointer to the spin lock to place in the acquired state.

Returns: SpinLock acquired the lock.

Definition at line 88 of file Synchronization.c.

◆ AcquireSpinLockOrFail()

BOOLEAN EFIAPI AcquireSpinLockOrFail ( IN OUT SPIN_LOCK * SpinLock )

Attempts to place a spin lock in the acquired state.

This function checks the state of the spin lock specified by SpinLock. If SpinLock is in the released state, then this function places SpinLock in the acquired state and returns TRUE. Otherwise, FALSE is returned. All state transitions of SpinLock must be performed using MP safe mechanisms.

If SpinLock is NULL, then ASSERT(). If SpinLock was not initialized with InitializeSpinLock(), then ASSERT().

Parameters

SpinLock A pointer to the spin lock to place in the acquired state.

Return values

TRUE	SpinLock was placed in the acquired state.
FALSE	SpinLock could not be acquired.

Definition at line 176 of file Synchronization.c.

◆ GetSpinLockProperties()

UINTN EFIAPI GetSpinLockProperties ( VOID )

Retrieves the architecture specific spin lock alignment requirements for optimal spin lock performance.

This function retrieves the spin lock alignment requirements for optimal performance on a given CPU architecture. The spin lock alignment is byte alignment. It must be a power of two and is returned by this function. If there are no alignment requirements, then 1 must be returned. The spin lock synchronization functions must function correctly if the spin lock size and alignment values returned by this function are not used at all. These values are hints to the consumers of the spin lock synchronization functions to obtain optimal spin lock performance.

Returns: The architecture specific spin lock alignment.

Definition at line 32 of file Synchronization.c.

◆ InitializeSpinLock()

SPIN_LOCK *EFIAPI InitializeSpinLock ( OUT SPIN_LOCK * SpinLock )

Initializes a spin lock to the released state and returns the spin lock.

This function initializes the spin lock specified by SpinLock to the released state, and returns SpinLock. Optimal performance can be achieved by calling GetSpinLockProperties() to determine the size and alignment requirements for SpinLock.

If SpinLock is NULL, then ASSERT().

Parameters

SpinLock A pointer to the spin lock to initialize to the released state.

Returns: SpinLock is in release state.

Definition at line 57 of file Synchronization.c.

◆ InterlockedCompareExchange16()

UINT16 EFIAPI InterlockedCompareExchange16	(	IN OUT volatile UINT16 *	Value,
		IN UINT16	CompareValue,
		IN UINT16	ExchangeValue
	)

Performs an atomic compare exchange operation on a 16-bit unsigned integer.

Performs an atomic compare exchange operation on the 16-bit unsigned integer specified by Value. If Value is equal to CompareValue, then Value is set to ExchangeValue and CompareValue is returned. If Value is not equal to CompareValue, then Value is returned. The compare exchange operation must be performed using MP safe mechanisms.

If Value is NULL, then ASSERT().

Parameters

Value	A pointer to the 16-bit value for the compare exchange operation.
CompareValue	16-bit value used in compare operation.
ExchangeValue	16-bit value used in exchange operation.

Returns: The original *Value before exchange.

Definition at line 296 of file Synchronization.c.

◆ InterlockedCompareExchange32()

UINT32 EFIAPI InterlockedCompareExchange32	(	IN OUT volatile UINT32 *	Value,
		IN UINT32	CompareValue,
		IN UINT32	ExchangeValue
	)

Performs an atomic compare exchange operation on a 32-bit unsigned integer.

Performs an atomic compare exchange operation on the 32-bit unsigned integer specified by Value. If Value is equal to CompareValue, then Value is set to ExchangeValue and CompareValue is returned. If Value is not equal to CompareValue, then Value is returned. The compare exchange operation must be performed using MP safe mechanisms.

If Value is NULL, then ASSERT().

Parameters

Value	A pointer to the 32-bit value for the compare exchange operation.
CompareValue	32-bit value used in compare operation.
ExchangeValue	32-bit value used in exchange operation.

Returns: The original *Value before exchange.

Definition at line 327 of file Synchronization.c.

◆ InterlockedCompareExchange64()

UINT64 EFIAPI InterlockedCompareExchange64	(	IN OUT volatile UINT64 *	Value,
		IN UINT64	CompareValue,
		IN UINT64	ExchangeValue
	)

Performs an atomic compare exchange operation on a 64-bit unsigned integer.

Performs an atomic compare exchange operation on the 64-bit unsigned integer specified by Value. If Value is equal to CompareValue, then Value is set to ExchangeValue and CompareValue is returned. If Value is not equal to CompareValue, then Value is returned. The compare exchange operation must be performed using MP safe mechanisms.

If Value is NULL, then ASSERT().

Parameters

Value	A pointer to the 64-bit value for the compare exchange operation.
CompareValue	64-bit value used in compare operation.
ExchangeValue	64-bit value used in exchange operation.

Returns: The original *Value before exchange.

Definition at line 357 of file Synchronization.c.

◆ InterlockedCompareExchangePointer()

VOID *EFIAPI InterlockedCompareExchangePointer	(	IN OUT VOID volatile	Value,
		IN VOID *	CompareValue,
		IN VOID *	ExchangeValue
	)

Performs an atomic compare exchange operation on a pointer value.

Performs an atomic compare exchange operation on the pointer value specified by Value. If Value is equal to CompareValue, then Value is set to ExchangeValue and CompareValue is returned. If Value is not equal to CompareValue, then Value is returned. The compare exchange operation must be performed using MP safe mechanisms.

If Value is NULL, then ASSERT().

Parameters

Value	A pointer to the pointer value for the compare exchange operation.
CompareValue	Pointer value used in compare operation.
ExchangeValue	Pointer value used in exchange operation.

Returns: The original *Value before exchange.

Definition at line 387 of file Synchronization.c.

◆ InterlockedDecrement()

UINT32 EFIAPI InterlockedDecrement ( IN volatile UINT32 * Value )

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 decremented value. The decrement operation must be performed using MP safe mechanisms.

If Value is NULL, then ASSERT().

Parameters

Value A pointer to the 32-bit value to decrement.

Returns: The decremented value.

Definition at line 267 of file Synchronization.c.

◆ InterlockedIncrement()

UINT32 EFIAPI InterlockedIncrement ( IN volatile UINT32 * Value )

Performs an atomic increment of an 32-bit unsigned integer.

Performs an atomic increment of the 32-bit unsigned integer specified by Value and returns the incremented value. The increment operation must be performed using MP safe mechanisms.

If Value is NULL, then ASSERT().

Parameters

Value A pointer to the 32-bit value to increment.

Returns: The incremented value.

Definition at line 243 of file Synchronization.c.

◆ ReleaseSpinLock()

SPIN_LOCK *EFIAPI ReleaseSpinLock ( IN OUT SPIN_LOCK * SpinLock )

Releases a spin lock.

This function places the spin lock specified by SpinLock in the release state and returns SpinLock.

If SpinLock is NULL, then ASSERT(). If SpinLock was not initialized with InitializeSpinLock(), then ASSERT().

Parameters

SpinLock A pointer to the spin lock to release.

Returns: SpinLock released lock.

Definition at line 212 of file Synchronization.c.

Macros

Functions

Detailed Description

Macro Definition Documentation

◆ SPIN_LOCK_ACQUIRED

◆ SPIN_LOCK_RELEASED

Function Documentation

◆ AcquireSpinLock()

◆ AcquireSpinLockOrFail()

◆ GetSpinLockProperties()

◆ InitializeSpinLock()

◆ InterlockedCompareExchange16()

◆ InterlockedCompareExchange32()

◆ InterlockedCompareExchange64()

◆ InterlockedCompareExchangePointer()

◆ InterlockedDecrement()

◆ InterlockedIncrement()

◆ ReleaseSpinLock()