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Rev	Author	Line No.	Line
2726	vana	1	/*++
		2
		3	Copyright (c) 1998 Intel Corporation
		4
		5	Module Name:
		6
		7	lock.c
		8
		9	Abstract:
		10
		11	Implements FLOCK
		12
		13
		14
		15	Revision History
		16
		17	--*/
		18
		19
		20	#include "lib.h"
		21
		22
		23	VOID
		24	InitializeLock (
		25	IN OUT FLOCK *Lock,
		26	IN EFI_TPL Priority
		27	)
		28	/*++
		29
		30	Routine Description:
		31
		32	Initialize a basic mutual exclusion lock. Each lock
		33	provides mutual exclusion access at it's task priority
		34	level. Since there is no-premption (at any TPL) or
		35	multiprocessor support, acquiring the lock only consists
		36	of raising to the locks TPL.
		37
		38	Note on a debug build the lock is acquired and released
		39	to help ensure proper usage.
		40
		41	Arguments:
		42
		43	Lock - The FLOCK structure to initialize
		44
		45	Priority - The task priority level of the lock
		46
		47
		48	Returns:
		49
		50	An initialized F Lock structure.
		51
		52	--*/
		53	{
		54	Lock->Tpl = Priority;
		55	Lock->OwnerTpl = 0;
		56	Lock->Lock = 0;
		57	}
		58
		59
		60	VOID
		61	AcquireLock (
		62	IN FLOCK *Lock
		63	)
		64	/*++
		65
		66	Routine Description:
		67
		68	Raising to the task priority level of the mutual exclusion
		69	lock, and then acquires ownership of the lock.
		70
		71	Arguments:
		72
		73	Lock - The lock to acquire
		74
		75	Returns:
		76
		77	Lock owned
		78
		79	--*/
		80	{
		81	RtAcquireLock (Lock);
		82	}
		83
		84
		85	VOID
		86	ReleaseLock (
		87	IN FLOCK *Lock
		88	)
		89	/*++
		90
		91	Routine Description:
		92
		93	Releases ownership of the mutual exclusion lock, and
		94	restores the previous task priority level.
		95
		96	Arguments:
		97
		98	Lock - The lock to release
		99
		100	Returns:
		101
		102	Lock unowned
		103
		104	--*/
		105	{
		106	RtReleaseLock (Lock);
		107	}

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