RW Semaphore 的协作图:

宏定义
#define	LOS_ERRNO_RWSEM_INVALID LOS_ERRNO_OS_ERROR(LOS_MOD_RWSEM, 0x00)

#define	LOS_ERRNO_RWSEM_PTR_NULL LOS_ERRNO_OS_ERROR(LOS_MOD_RWSEM, 0x01)

#define	LOS_ERRNO_RWSEM_ALL_BUSY LOS_ERRNO_OS_ERROR(LOS_MOD_RWSEM, 0x02)

#define	LOS_ERRNO_RWSEM_PEND_INTERR LOS_ERRNO_OS_ERROR(LOS_MOD_RWSEM, 0x03)

#define	LOS_ERRNO_RWSEM_PEND_IN_LOCK LOS_ERRNO_OS_ERROR(LOS_MOD_RWSEM, 0x04)

#define	LOS_ERRNO_RWSEM_TIMEOUT LOS_ERRNO_OS_ERROR(LOS_MOD_RWSEM, 0x05)

#define	LOS_ERRNO_RWSEM_PENDED LOS_ERRNO_OS_ERROR(LOS_MOD_RWSEM, 0x06)

#define	LOS_ERRNO_RWSEM_INVALID_STATUS LOS_ERRNO_OS_ERROR(LOS_MOD_RWSEM, 0x07)

#define	LOS_ERRNO_RWSEM_UNAVAILABLE LOS_ERRNO_OS_ERROR(LOS_MOD_RWSEM, 0x08)

函数
UINT32	LOS_RwsemCreate (UINT32 *semHandle)
	Create a RW semaphore.

UINT32	LOS_RwsemDelete (UINT32 semHandle)
	Delete a RW semaphore.

UINT32	LOS_RwsemPendRead (UINT32 semHandle, UINT32 timeout)
	Request a RW semaphore.

UINT32	LOS_RwsemPostRead (UINT32 semHandle)
	Release a RW semaphore.

UINT32	LOS_RwsemPendWrite (UINT32 semHandle, UINT32 timeout)
	Request a RW semaphore.

UINT32	LOS_RwsemPostWrite (UINT32 semHandle)
	Release a RW semaphore.

UINT32	LOS_RwsemDowngradeWrite (UINT32 semHandle)
	Release a RW semaphore.

详细描述

宏定义说明

◆ LOS_ERRNO_RWSEM_ALL_BUSY

#define LOS_ERRNO_RWSEM_ALL_BUSY LOS_ERRNO_OS_ERROR(LOS_MOD_RWSEM, 0x02)

RW Semaphore error code: No RW semaphore control structure is available.

Value: 0x02002202.

Solution: Perform corresponding operations based on the requirements in the code context.

◆ LOS_ERRNO_RWSEM_INVALID

#define LOS_ERRNO_RWSEM_INVALID LOS_ERRNO_OS_ERROR(LOS_MOD_RWSEM, 0x00)

RW Semaphore error code: Invalid parameter.

Value: 0x02002200.

Solution: Change the passed-in invalid parameter value to a valid value.

◆ LOS_ERRNO_RWSEM_INVALID_STATUS

#define LOS_ERRNO_RWSEM_INVALID_STATUS LOS_ERRNO_OS_ERROR(LOS_MOD_RWSEM, 0x07)

RW Semaphore error code: Invalid status.

Value: 0x02002207.

Solution: Use the pend and post APIs in pairs.

◆ LOS_ERRNO_RWSEM_PEND_IN_LOCK

#define LOS_ERRNO_RWSEM_PEND_IN_LOCK LOS_ERRNO_OS_ERROR(LOS_MOD_RWSEM, 0x04)

RW Semaphore error code: The task is unable to request a semaphore because task scheduling is locked.

Value: 0x02002204.

Solution: Do not call the API when task scheduling is locked.

◆ LOS_ERRNO_RWSEM_PEND_INTERR

#define LOS_ERRNO_RWSEM_PEND_INTERR LOS_ERRNO_OS_ERROR(LOS_MOD_RWSEM, 0x03)

RW Semaphore error code: The API is called during an interrupt, which is forbidden.

Value: 0x02002203.

Solution: Do not call the API during an interrupt.

◆ LOS_ERRNO_RWSEM_PENDED

#define LOS_ERRNO_RWSEM_PENDED LOS_ERRNO_OS_ERROR(LOS_MOD_RWSEM, 0x06)

RW Semaphore error code: The waiting queue for the RW semaphore is not empty.

Value: 0x02002206.

Solution: Delete the RW semaphore after awaking all tasks that are waiting on the semaphore.

◆ LOS_ERRNO_RWSEM_PTR_NULL

#define LOS_ERRNO_RWSEM_PTR_NULL LOS_ERRNO_OS_ERROR(LOS_MOD_RWSEM, 0x01)

RW Semaphore error code: Null pointer.

Value: 0x02002201.

Solution: Change the passed-in null pointer to a valid non-null pointer.

◆ LOS_ERRNO_RWSEM_TIMEOUT

#define LOS_ERRNO_RWSEM_TIMEOUT LOS_ERRNO_OS_ERROR(LOS_MOD_RWSEM, 0x05)

RW Semaphore error code: The request for a RW semaphore times out.

Value: 0x02002205.

Solution: Change the passed-in parameter value to the value within the valid range.

◆ LOS_ERRNO_RWSEM_UNAVAILABLE

#define LOS_ERRNO_RWSEM_UNAVAILABLE LOS_ERRNO_OS_ERROR(LOS_MOD_RWSEM, 0x08)

RW Semaphore error code: The RW semaphore is not immediately available.

Value: 0x02002208.

Solution: Obtain the RW semaphore only when the semaphore is available.

函数说明

◆ LOS_RwsemCreate()

UINT32 LOS_RwsemCreate ( UINT32 * semHandle )

extern

Create a RW semaphore.

Description:: This API is used to create a RW semaphore control structure and return the ID of this semaphore control structure.

注意: None.

参数

semHandle [OUT] ID of the RW semaphore control structure that is initialized.

返回值

LOS_ERRNO_RWSEM_PTR_NULL	The passed-in semHandle value is NULL.
LOS_ERRNO_RWSEM_ALL_BUSY	No RW semaphore control structure is available.
LOS_OK	The RW semaphore is successfully created.

Dependency:: los_rwsem.h: the header file that contains the API declaration.

参见: LOS_RwsemDelete

◆ LOS_RwsemDelete()

UINT32 LOS_RwsemDelete ( UINT32 semHandle )

extern

Delete a RW semaphore.

Description:: This API is used to delete a RW semaphore control structure that has an ID specified by semHandle.

注意: The specified rwsem id must be created first before deleting it.

参数

semHandle [IN] ID of the RW semaphore control structure to be deleted. The ID of the RW semaphore control structure is obtained from semaphore creation.

返回值

LOS_ERRNO_RWSEM_INVALID	The passed-in RW semHandle value is invalid.
LOS_ERRNO_RWSEM_PENDED	The waiting queue for the RW semaphore is not empty.
LOS_OK	The RW semaphore control structure is successfully deleted.

Dependency:: los_rwsem.h: the header file that contains the API declaration.

参见: LOS_RwsemCreate

◆ LOS_RwsemDowngradeWrite()

UINT32 LOS_RwsemDowngradeWrite ( UINT32 semHandle )

extern

Release a RW semaphore.

Description:: This API is used to downgrade the write semaphore to the read semaphore.

注意: The specified rwsem id must be created first.

参数

semHandle [IN] ID of the RW semaphore control structure to be downgraded. The ID of the RW semaphore control structure is obtained from semaphore creation.

返回值

LOS_ERRNO_RWSEM_INVALID	The passed-in RW semHandle value is invalid.
LOS_ERRNO_RWSEM_INVALID_STATUS	Invalid status.
LOS_OK	The RW semaphore is successfully released.

Dependency:: los_rwsem.h: the header file that contains the API declaration.

参见: LOS_RwsemPendWrite | LOS_RwsemCreate

◆ LOS_RwsemPendRead()

UINT32 LOS_RwsemPendRead	(	UINT32	semHandle,
		UINT32	timeout
	)

extern

Request a RW semaphore.

Description:: This API is used to request a RW semaphore based on the semaphore control structure ID specified by semHandle and the parameter that specifies the timeout period.

注意: Do not pend rwsem during an interrupt. Do not pend rwsem in a system task, such as idle or swtmr task. The specified rwsem id must be created first. Do not recommend to use this API in software timer callback.

参数

semHandle	[IN] ID of the RW semaphore control structure to be requested. The ID of the RW semaphore control structure is obtained from semaphore creation.
timeout	[IN] Timeout interval for waiting on the RW semaphore. The value range is [0, 0xFFFFFFFF]. If the value is set to 0, the RW semaphore is not waited on. If the value is set to 0xFFFFFFFF, the RW semaphore is waited on forever(unit: Tick).

返回值

LOS_ERRNO_RWSEM_INVALID	The passed-in semHandle value is invalid.
LOS_ERRNO_RWSEM_PEND_INTERR	The API is called during an interrupt, which is forbidden.
LOS_ERRNO_RWSEM_PEND_IN_LOCK	The task is unable to request a RW semaphore because task scheduling is locked.
LOS_ERRNO_RWSEM_TIMEOUT	The request for the RW semaphore times out.
LOS_OK	The RW semaphore request succeeds.

Dependency:: los_rwsem.h: the header file that contains the API declaration.

参见: LOS_RwsemPostRead | LOS_RwsemCreate

◆ LOS_RwsemPendWrite()

UINT32 LOS_RwsemPendWrite	(	UINT32	semHandle,
		UINT32	timeout
	)

extern

Request a RW semaphore.

Description:: This API is used to request a RW semaphore based on the semaphore control structure ID specified by semHandle and the parameter that specifies the timeout period.

注意: Do not pend rwsem during an interrupt. Do not pend rwsem in a system task, such as idle or swtmr task. The specified rwsem id must be created first. Do not recommend to use this API in software timer callback.

参数

semHandle	[IN] ID of the RW semaphore control structure to be requested. The ID of the RW semaphore control structure is obtained from semaphore creation.
timeout	[IN] Timeout interval for waiting on the RW semaphore. The value range is [0, 0xFFFFFFFF]. If the value is set to 0, the RW semaphore is not waited on. If the value is set to 0xFFFFFFFF, the RWsemaphore is waited on forever(unit: Tick).

返回值

LOS_ERRNO_RWSEM_INVALID	The passed-in semHandle value is invalid.
LOS_ERRNO_RWSEM_PEND_INTERR	The API is called during an interrupt, which is forbidden.
LOS_ERRNO_RWSEM_PEND_IN_LOCK	The task is unable to request a RW semaphore because task scheduling is locked.
LOS_ERRNO_RWSEM_TIMEOUT	The request for the semaphore times out.
LOS_OK	The RW semaphore request succeeds.

Dependency:: los_rwsem.h: the header file that contains the API declaration.

参见: LOS_RwsemPostWrite | LOS_RwsemCreate

◆ LOS_RwsemPostRead()

UINT32 LOS_RwsemPostRead ( UINT32 semHandle )

extern

Release a RW semaphore.

Description:: This API is used to release a RW semaphore that has a semaphore control structure ID specified by semHandle.

注意: The specified rwsem id must be created first.

参数

semHandle [IN] ID of the RW semaphore control structure to be released. The ID of the RW semaphore control structure is obtained from semaphore creation.

返回值

LOS_ERRNO_RWSEM_INVALID	The passed-in semHandle value is invalid.
LOS_ERRNO_RWSEM_INVALID_STATUS	Invalid status.
LOS_OK	The RW semaphore is successfully released.

Dependency:: los_rwsem.h: the header file that contains the API declaration.

参见: LOS_RwsemPendRead | LOS_RwsemCreate

◆ LOS_RwsemPostWrite()

UINT32 LOS_RwsemPostWrite ( UINT32 semHandle )

extern

Release a RW semaphore.

Description:: This API is used to release a RW semaphore that has a RW semaphore control structure ID specified by semHandle.

注意: The specified rwsem id must be created first.

参数

semHandle [IN] ID of the RW semaphore control structure to be released. The ID of the RW semaphore control structure is obtained from semaphore creation.

返回值

LOS_ERRNO_RWSEM_INVALID	The passed-in semHandle value is invalid.
LOS_ERRNO_RWSEM_INVALID_STATUS	Invalid status.
LOS_OK	The RW semaphore is successfully released.

Dependency:: los_rwsem.h: the header file that contains the API declaration.

参见: LOS_RwsemPendWrite | LOS_RwsemCreate