WebSVN – Kolibri OS – Diff – /drivers/include/linux/mutex.h


/*
 * Mutexes: blocking mutual exclusion locks
 *
 * started by Ingo Molnar:
 *
 *  Copyright (C) 2004, 2005, 2006 Red Hat, Inc., Ingo Molnar 
 *
 * This file contains the main data structure and API definitions.
 */
#ifndef __LINUX_MUTEX_H
#define __LINUX_MUTEX_H
 
#include 
#include 
#include 
#include 
#include 
#include 
#include 
 
/*
 * Simple, straightforward mutexes with strict semantics:
 *
 * - only one task can hold the mutex at a time
 * - only the owner can unlock the mutex
 * - multiple unlocks are not permitted
 * - recursive locking is not permitted
 * - a mutex object must be initialized via the API
 * - a mutex object must not be initialized via memset or copying
 * - task may not exit with mutex held
 * - memory areas where held locks reside must not be freed
 * - held mutexes must not be reinitialized
 * - mutexes may not be used in hardware or software interrupt
 *   contexts such as tasklets and timers
 *
 * These semantics are fully enforced when DEBUG_MUTEXES is
 * enabled. Furthermore, besides enforcing the above rules, the mutex
 * debugging code also implements a number of additional features
 * that make lock debugging easier and faster:
 *
 * - uses symbolic names of mutexes, whenever they are printed in debug output
 * - point-of-acquire tracking, symbolic lookup of function names
 * - list of all locks held in the system, printout of them
 * - owner tracking
 * - detects self-recursing locks and prints out all relevant info
 * - detects multi-task circular deadlocks and prints out all affected
 *   locks and tasks (and only those tasks)
 */
struct mutex {
	/* 1: unlocked, 0: locked, negative: locked, possible waiters */
	struct list_head	wait_list;
	atomic_t            	count;
};
 
/*
 * This is the control structure for tasks blocked on mutex,
 * which resides on the blocked task's kernel stack:
 */
struct mutex_waiter {
	struct list_head	list;
	void		*task;
};
 
 
#define __MUTEX_INITIALIZER(lockname) \
                { .wait_list = LIST_HEAD_INIT(lockname.wait_list), \
                  .count = ATOMIC_INIT(1) \
                }
 
#define DEFINE_MUTEX(mutexname) \
        struct mutex mutexname = __MUTEX_INITIALIZER(mutexname)
 
void __attribute__ ((fastcall)) __attribute__ ((dllimport))
     mutex_init(struct mutex*)__asm__("MutexInit");
void __attribute__ ((fastcall)) __attribute__ ((dllimport))
     mutex_lock(struct mutex*)__asm__("MutexLock");
void __attribute__ ((fastcall)) __attribute__ ((dllimport))
     mutex_unlock(struct mutex*)__asm__("MutexUnlock");
 
static inline int mutex_lock_interruptible(struct mutex *lock)
{
    mutex_lock(lock);
    return 0;
}
 
# define mutex_lock_nest_lock(lock, nest_lock) mutex_lock(lock)
 
 
/**
 * mutex_is_locked - is the mutex locked
 * @lock: the mutex to be queried
 *
 * Returns 1 if the mutex is locked, 0 if unlocked.
 */
static inline int mutex_is_locked(struct mutex *lock)
{
	return atomic_read(&lock->count) != 1;
}
 
static inline int mutex_trylock(struct mutex *lock)
{
    if (likely(atomic_cmpxchg(&lock->count, 1, 0) == 1))
        return 1;
    return 0;
}
 
static inline void mutex_destroy(struct mutex *lock)
{
 
};
 
#endif

Subversion Repositories Kolibri OS

(root)/drivers/include/linux/mutex.h – Rev 6082 → 9833

Rev 6082		Rev 9833
1	/*	1	/*
2	* Mutexes: blocking mutual exclusion locks	2	* Mutexes: blocking mutual exclusion locks
3	*	3	*
4	* started by Ingo Molnar:	4	* started by Ingo Molnar:
5	*	5	*
6	* Copyright (C) 2004, 2005, 2006 Red Hat, Inc., Ingo Molnar	6	* Copyright (C) 2004, 2005, 2006 Red Hat, Inc., Ingo Molnar
7	*	7	*
8	* This file contains the main data structure and API definitions.	8	* This file contains the main data structure and API definitions.
9	*/	9	*/
10	#ifndef __LINUX_MUTEX_H	10	#ifndef __LINUX_MUTEX_H
11	#define __LINUX_MUTEX_H	11	#define __LINUX_MUTEX_H
12		12
13	#include	13	#include
14	#include	14	#include
15	#include	15	#include
16	#include	16	#include
17	#include	17	#include
18	#include	18	#include
19	#include	19	#include
20		20
21	/*	21	/*
22	* Simple, straightforward mutexes with strict semantics:	22	* Simple, straightforward mutexes with strict semantics:
23	*	23	*
24	* - only one task can hold the mutex at a time	24	* - only one task can hold the mutex at a time
25	* - only the owner can unlock the mutex	25	* - only the owner can unlock the mutex
26	* - multiple unlocks are not permitted	26	* - multiple unlocks are not permitted
27	* - recursive locking is not permitted	27	* - recursive locking is not permitted
28	* - a mutex object must be initialized via the API	28	* - a mutex object must be initialized via the API
29	* - a mutex object must not be initialized via memset or copying	29	* - a mutex object must not be initialized via memset or copying
30	* - task may not exit with mutex held	30	* - task may not exit with mutex held
31	* - memory areas where held locks reside must not be freed	31	* - memory areas where held locks reside must not be freed
32	* - held mutexes must not be reinitialized	32	* - held mutexes must not be reinitialized
33	* - mutexes may not be used in hardware or software interrupt	33	* - mutexes may not be used in hardware or software interrupt
34	* contexts such as tasklets and timers	34	* contexts such as tasklets and timers
35	*	35	*
36	* These semantics are fully enforced when DEBUG_MUTEXES is	36	* These semantics are fully enforced when DEBUG_MUTEXES is
37	* enabled. Furthermore, besides enforcing the above rules, the mutex	37	* enabled. Furthermore, besides enforcing the above rules, the mutex
38	* debugging code also implements a number of additional features	38	* debugging code also implements a number of additional features
39	* that make lock debugging easier and faster:	39	* that make lock debugging easier and faster:
40	*	40	*
41	* - uses symbolic names of mutexes, whenever they are printed in debug output	41	* - uses symbolic names of mutexes, whenever they are printed in debug output
42	* - point-of-acquire tracking, symbolic lookup of function names	42	* - point-of-acquire tracking, symbolic lookup of function names
43	* - list of all locks held in the system, printout of them	43	* - list of all locks held in the system, printout of them
44	* - owner tracking	44	* - owner tracking
45	* - detects self-recursing locks and prints out all relevant info	45	* - detects self-recursing locks and prints out all relevant info
46	* - detects multi-task circular deadlocks and prints out all affected	46	* - detects multi-task circular deadlocks and prints out all affected
47	* locks and tasks (and only those tasks)	47	* locks and tasks (and only those tasks)
48	*/	48	*/
49	struct mutex {	49	struct mutex {
50	/* 1: unlocked, 0: locked, negative: locked, possible waiters */	50	/* 1: unlocked, 0: locked, negative: locked, possible waiters */
51	struct list_head wait_list;	51	struct list_head wait_list;
52	atomic_t count;	52	atomic_t count;
53	};	53	};
54		54
55	/*	55	/*
56	* This is the control structure for tasks blocked on mutex,	56	* This is the control structure for tasks blocked on mutex,
57	* which resides on the blocked task's kernel stack:	57	* which resides on the blocked task's kernel stack:
58	*/	58	*/
59	struct mutex_waiter {	59	struct mutex_waiter {
60	struct list_head list;	60	struct list_head list;
61	int *task;	61	void *task;
62	};	62	};
63		63
64		64
65	#define __MUTEX_INITIALIZER(lockname) \	65	#define __MUTEX_INITIALIZER(lockname) \
66	{ .wait_list = LIST_HEAD_INIT(lockname.wait_list), \	66	{ .wait_list = LIST_HEAD_INIT(lockname.wait_list), \
67	.count = ATOMIC_INIT(1) \	67	.count = ATOMIC_INIT(1) \
68	}	68	}
69		69
70	#define DEFINE_MUTEX(mutexname) \	70	#define DEFINE_MUTEX(mutexname) \
71	struct mutex mutexname = __MUTEX_INITIALIZER(mutexname)	71	struct mutex mutexname = __MUTEX_INITIALIZER(mutexname)
72		72
73	void __attribute__ ((fastcall)) __attribute__ ((dllimport))	73	void __attribute__ ((fastcall)) __attribute__ ((dllimport))
74	mutex_init(struct mutex*)__asm__("MutexInit");	74	mutex_init(struct mutex*)__asm__("MutexInit");
75	void __attribute__ ((fastcall)) __attribute__ ((dllimport))	75	void __attribute__ ((fastcall)) __attribute__ ((dllimport))
76	mutex_lock(struct mutex*)__asm__("MutexLock");	76	mutex_lock(struct mutex*)__asm__("MutexLock");
77	void __attribute__ ((fastcall)) __attribute__ ((dllimport))	77	void __attribute__ ((fastcall)) __attribute__ ((dllimport))
78	mutex_unlock(struct mutex*)__asm__("MutexUnlock");	78	mutex_unlock(struct mutex*)__asm__("MutexUnlock");
79		79
80	static inline int mutex_lock_interruptible(struct mutex *lock)	80	static inline int mutex_lock_interruptible(struct mutex *lock)
81	{	81	{
82	mutex_lock(lock);	82	mutex_lock(lock);
83	return 0;	83	return 0;
84	}	84	}
85		85
86	# define mutex_lock_nest_lock(lock, nest_lock) mutex_lock(lock)	86	# define mutex_lock_nest_lock(lock, nest_lock) mutex_lock(lock)
87		87
88		88
89	/**	89	/**
90	* mutex_is_locked - is the mutex locked	90	* mutex_is_locked - is the mutex locked
91	* @lock: the mutex to be queried	91	* @lock: the mutex to be queried
92	*	92	*
93	* Returns 1 if the mutex is locked, 0 if unlocked.	93	* Returns 1 if the mutex is locked, 0 if unlocked.
94	*/	94	*/
95	static inline int mutex_is_locked(struct mutex *lock)	95	static inline int mutex_is_locked(struct mutex *lock)
96	{	96	{
97	return atomic_read(&lock->count) != 1;	97	return atomic_read(&lock->count) != 1;
98	}	98	}
99		99
100	static inline int mutex_trylock(struct mutex *lock)	100	static inline int mutex_trylock(struct mutex *lock)
101	{	101	{
102	if (likely(atomic_cmpxchg(&lock->count, 1, 0) == 1))	102	if (likely(atomic_cmpxchg(&lock->count, 1, 0) == 1))
103	return 1;	103	return 1;
104	return 0;	104	return 0;
105	}	105	}
106		106
107	static inline void mutex_destroy(struct mutex *lock)	107	static inline void mutex_destroy(struct mutex *lock)
108	{	108	{
109		109
110	};	110	};
111		111
112	#endif	112	#endif