Rwlock

Rwlock 的协作图:

结构体
struct	OsRwlock

类型定义
typedef struct OsRwlock	LosRwlock

函数
UINT32	LOS_RwlockInit (LosRwlock *rwlock)
	Init a rwlock. 更多...
UINT32	LOS_RwlockDestroy (LosRwlock *rwlock)
	Destroy a rwlock. 更多...
UINT32	LOS_RwlockRdLock (LosRwlock *rwlock, UINT32 timeout)
	Wait to lock a read lock. 更多...
UINT32	LOS_RwlockTryRdLock (LosRwlock *rwlock)
	Try wait to lock a read lock. 更多...
UINT32	LOS_RwlockWrLock (LosRwlock *rwlock, UINT32 timeout)
	Wait to lock a write lock. 更多...
UINT32	LOS_RwlockTryWrLock (LosRwlock *rwlock)
	Try wait to lock a write lock. 更多...
UINT32	LOS_RwlockUnLock (LosRwlock *rwlock)
	Release a rwlock. 更多...

详细描述

类型定义说明

LosRwlock

typedef struct OsRwlock LosRwlock

Rwlock object.

函数说明

LOS_RwlockDestroy()

UINT32 LOS_RwlockDestroy

(

LosRwlock *

rwlock

)

Destroy a rwlock.

Description:

This API is used to delete a specified rwlock. Return LOS_OK on deleting successfully, return specific error code otherwise.

注意

• The specific rwlock should be created firstly.
• The rwlock can be deleted successfully only if no other tasks pend on it.

参数

rwlock

[IN] Handle of the rwlock to be deleted.

返回值

#LOS_EINVAL	The rwlock pointer is NULL.
#LOS_EBUSY	Tasks pended on this rwlock.
#LOS_EBADF	The lock has been destroyed or broken.
#LOS_OK	The rwlock is successfully deleted.

Dependency:

• los_rwlock.h: the header file that contains the API declaration.

参见

LOS_RwlockInit

Destroy a rwlock.

在文件 los_rwlock.c 第 102 行定义.

{
    UINT32 intSave;
 
    if (rwlock == NULL) {
        return LOS_EINVAL;
    }
 
    SCHEDULER_LOCK(intSave);
    if ((rwlock->magic & RWLOCK_COUNT_MASK) != OS_RWLOCK_MAGIC) {
        SCHEDULER_UNLOCK(intSave);
        return LOS_EBADF;
    }
 
    if (rwlock->rwCount != 0) {
        SCHEDULER_UNLOCK(intSave);
        return LOS_EBUSY;
    }
 
    (VOID)memset_s(rwlock, sizeof(LosRwlock), 0, sizeof(LosRwlock));
    SCHEDULER_UNLOCK(intSave);
    return LOS_OK;
}

LOS_RwlockInit()

UINT32 LOS_RwlockInit

(

LosRwlock *

rwlock

)

Init a rwlock.

Description:

This API is used to Init a rwlock. A rwlock handle is assigned to rwlockHandle when the rwlock is init successfully. Return LOS_OK on creating successful, return specific error code otherwise.

参数

rwlock

[IN] Handle pointer of the successfully init rwlock.

返回值

#LOS_EINVAL	The rwlock pointer is NULL.
#LOS_EPERM	Multiply initialization.
#LOS_OK	The rwlock is successfully created.

Dependency:

• los_rwlock.h: the header file that contains the API declaration.

参见

LOS_RwlockDestroy

Init a rwlock.

在文件 los_rwlock.c 第 79 行定义.

{
    UINT32 intSave;
 
    if (rwlock == NULL) {
        return LOS_EINVAL;
    }
 
    SCHEDULER_LOCK(intSave);
    if ((rwlock->magic & RWLOCK_COUNT_MASK) == OS_RWLOCK_MAGIC) {
        SCHEDULER_UNLOCK(intSave);
        return LOS_EPERM;
    }
 
    rwlock->rwCount = 0;
    rwlock->writeOwner = NULL;
    LOS_ListInit(&(rwlock->readList));
    LOS_ListInit(&(rwlock->writeList));
    rwlock->magic = OS_RWLOCK_MAGIC;
    SCHEDULER_UNLOCK(intSave);
    return LOS_OK;
}

函数调用图:

LOS_RwlockRdLock()

UINT32 LOS_RwlockRdLock	(	LosRwlock *	rwlock,
		UINT32	timeout
	)

Wait to lock a read lock.

Description:

This API is used to wait for a specified period of time to lock a read lock.

注意

• The specific rwlock should be created firstly.
• The function fails if the rwlock that is waited on is already locked by another thread when the task scheduling is disabled.
• Do not wait on a rwlock during an interrupt.
• The function fails when other tasks have the write lock or there are some task pending on the write list with the higher priority.
• A recursive rwlock can be locked more than once by the same thread.
• Do not call this API in software timer callback.

参数

rwlock	[IN] Handle of the rwlock to be waited on.
timeout	[IN] Waiting time. The value range is [0, LOS_WAIT_FOREVER](unit: Tick).

返回值

#LOS_EINVAL	The rwlock pointer is NULL, The timeout is zero or Lock status error.
#LOS_EINTR	The rwlock is being locked during an interrupt.
#LOS_EBADF	The lock has been destroyed or broken.
#LOS_EDEADLK	Rwlock error check failed or System locked task scheduling.
#LOS_ETIMEDOUT	The rwlock waiting times out.
#LOS_EPERM	The rwlock is used in system tasks.
#LOS_OK	The rwlock is successfully locked.

Dependency:

• los_rwlock.h: the header file that contains the API declaration.

参见

LOS_RwlockInit | LOS_RwlockUnLock

Wait to lock a read lock.

在文件 los_rwlock.c 第 321 行定义.

{
    UINT32 intSave;
 
    UINT32 ret = OsRwlockCheck(rwlock);
    if (ret != LOS_OK) {
        return ret;
    }
 
    SCHEDULER_LOCK(intSave);
    ret = OsRwlockRdUnsafe(rwlock, timeout);
    SCHEDULER_UNLOCK(intSave);
    return ret;
}

函数调用图:

LOS_RwlockTryRdLock()

UINT32 LOS_RwlockTryRdLock

(

LosRwlock *

rwlock

)

Try wait to lock a read lock.

Description:

This API is used to wait for a specified period of time to lock a read lock.

注意

• The specific rwlock should be created firstly.
• The function fails if the rwlock that is waited on is already locked by another thread when the task scheduling is disabled.
• Do not wait on a rwlock during an interrupt.
• The function fails when other tasks have the write lock or there are some task pending on the write list with the higher priority.
• A recursive rwlock can be locked more than once by the same thread.
• Do not call this API in software timer callback.

参数

rwlock

[IN] Handle of the rwlock to be waited on.

返回值

#LOS_EINVAL	The rwlock pointer is NULL or Lock status error.
#LOS_EINTR	The rwlock is being locked during an interrupt.
#LOS_EBUSY	Fail to get the rwlock, the rwlock has been used.
#LOS_EBADF	The lock has been destroyed or broken.
#LOS_EDEADLK	rwlock error check failed or System locked task scheduling.
#LOS_ETIMEDOUT	The rwlock waiting times out.
#LOS_EPERM	The rwlock is used in system tasks.
#LOS_OK	The rwlock is successfully locked.

Dependency:

• los_rwlock.h: the header file that contains the API declaration.

参见

LOS_RwlockInit | LOS_RwlockUnLock

Try wait to lock a read lock.

在文件 los_rwlock.c 第 336 行定义.

{
    UINT32 intSave;
 
    UINT32 ret = OsRwlockCheck(rwlock);
    if (ret != LOS_OK) {
        return ret;
    }
 
    SCHEDULER_LOCK(intSave);
    ret = OsRwlockTryRdUnsafe(rwlock, 0);//所谓尝试就是没锁爷就返回,不等待,不纠结.当前任务也不会被挂起
    SCHEDULER_UNLOCK(intSave);
    return ret;
}

函数调用图:

LOS_RwlockTryWrLock()

UINT32 LOS_RwlockTryWrLock

(

LosRwlock *

rwlock

)

Try wait to lock a write lock.

Description:

This API is used to wait for a specified period of time to lock a write lock.

注意

• The specific rwlock should be created firstly.
• The function fails if the rwlock that is waited on is already locked by another thread when the task scheduling. is disabled.
• Do not wait on a rwlock during an interrupt.
• The funtion fails when other tasks have the read or write lock.
• A recursive rwlock can be locked more than once by the same thread.
• Do not call this API in software timer callback.

参数

rwlock

[IN] Handle of the rwlock to be waited on.

返回值

#LOS_EINVAL	The rwlock pointer is NULL or Lock status error.
#LOS_EINTR	The rwlock is being locked during an interrupt.
#LOS_EBUSY	Fail to get the rwlock, the rwlock has been used.
#LOS_EBADF	The lock has been destroyed or broken.
#LOS_EDEADLK	rwlock error check failed or System locked task scheduling.
#LOS_ETIMEDOUT	The rwlock waiting times out.
#LOS_EPERM	The rwlock is used in system tasks.
#LOS_OK	The rwlock is successfully locked.

Dependency:

• los_rwlock.h: the header file that contains the API declaration.

参见

LOS_RwlockInit | LOS_RwlockUnLock

Try wait to lock a write lock.

在文件 los_rwlock.c 第 366 行定义.

{
    UINT32 intSave;
 
    UINT32 ret = OsRwlockCheck(rwlock);
    if (ret != LOS_OK) {
        return ret;
    }
 
    SCHEDULER_LOCK(intSave);
    ret = OsRwlockTryWrUnsafe(rwlock, 0);//所谓尝试就是没锁爷就返回,不等待,不纠结.当前任务也不会被挂起
    SCHEDULER_UNLOCK(intSave);
    return ret;
}

函数调用图:

LOS_RwlockUnLock()

UINT32 LOS_RwlockUnLock

(

LosRwlock *

rwlock

)

Release a rwlock.

Description:

This API is used to release a specified rwlock.

注意

• The specific rwlock should be created firstly.
• Do not release a rwlock during an interrupt.
• When the write list is null and the read list is not null, all the task pending on the read list will be waken.
• When the write list is not null and the read list is null, the task pending on the read list will be waken by the priority.
• When the write list and the read list are not null, all the task pending on the both list will be waken by the priority.
• If the task on the write list has the same priority as the task on the read list, the forth will be waken.
• If a recursive rwlock is locked for many times, it must be unlocked for the same times to be released.

参数

rwlock

[IN] Handle of the rwlock to be released.

返回值

#LOS_EINVAL	The rwlock pointer is NULL, The timeout is zero or Lock status error.
#LOS_EINTR	The rwlock is being locked during an interrupt.
#LOS_EPERM	The rwlock is not locked or has been used.
#LOS_EBADF	The lock has been destroyed or broken.
#LOS_EDEADLK	rwlock error check failed or System locked task scheduling.
#LOS_ETIMEDOUT	The rwlock waiting times out.
#LOS_EPERM	The rwlock is used in system tasks.
#LOS_OK	The rwlock is successfully locked.

Dependency:

• los_mux.h: the header file that contains the API declaration.

参见

LOS_RwlockInit | LOS_ReadLock | LOS_WriteLock

Release a rwlock.

在文件 los_rwlock.c 第 482 行定义.

{
    UINT32 intSave;
    BOOL needSched = FALSE;
 
    UINT32 ret = OsRwlockCheck(rwlock);
    if (ret != LOS_OK) {
        return ret;
    }
 
    SCHEDULER_LOCK(intSave);
    ret = OsRwlockUnlockUnsafe(rwlock, &needSched);
    SCHEDULER_UNLOCK(intSave);
    LOS_MpSchedule(OS_MP_CPU_ALL);//设置调度CPU的方式,所有CPU参与调度
    if (needSched == TRUE) {//是否需要调度
        LOS_Schedule();//产生调度,切换任务执行
    }
    return ret;
}

函数调用图:

LOS_RwlockWrLock()

UINT32 LOS_RwlockWrLock	(	LosRwlock *	rwlock,
		UINT32	timeout
	)

Wait to lock a write lock.

Description:

This API is used to wait for a specified period of time to lock a write lock.

注意

• The specific rwlock should be created firstly.
• The function fails if the rwlock that is waited on is already locked by another thread when the task scheduling. is disabled.
• Do not wait on a rwlock during an interrupt.
• The funtion fails when other tasks have the read or write lock.
• A recursive rwlock can be locked more than once by the same thread.
• Do not call this API in software timer callback.

参数

rwlock	[IN] Handle of the rwlock to be waited on.
timeout	[IN] Waiting time. The value range is [0, LOS_WAIT_FOREVER](unit: Tick).

返回值

#LOS_EINVAL	The rwlock pointer is NULL, The timeout is zero or Lock status error.
#LOS_EINTR	The rwlock is being locked during an interrupt.
#LOS_EBADF	The lock has been destroyed or broken.
#LOS_EDEADLK	Rwlock error check failed or System locked task scheduling.
#LOS_ETIMEDOUT	The rwlock waiting times out.
#LOS_EPERM	The rwlock is used in system tasks.
#LOS_OK	The rwlock is successfully locked.

Dependency:

• los_rwlock.h: the header file that contains the API declaration.

参见

LOS_MuxInit | LOS_MuxUnlock

Wait to lock a write lock.

在文件 los_rwlock.c 第 351 行定义.

{
    UINT32 intSave;
 
    UINT32 ret = OsRwlockCheck(rwlock);
    if (ret != LOS_OK) {
        return ret;
    }
 
    SCHEDULER_LOCK(intSave);
    ret = OsRwlockWrUnsafe(rwlock, timeout);
    SCHEDULER_UNLOCK(intSave);
    return ret;
}

函数调用图: