Message based implementation of Bottom Half Processor

Bottom Half Processor module for generic IRQ offloading using messages. More...

Detailed Description

Bottom Half Processor module for generic IRQ offloading using messages.

Note

Offloading ISRs with messages is in general a terrible idea, because messages can be lost. Use it with care or prefer alternatives such as Event based implementation of Bottom Half Processor.

Author

José I. Alamos jose..nosp@m.alam.nosp@m.os@ha.nosp@m.w-ha.nosp@m.mburg.nosp@m..de

Data Structures
struct	bhp_msg_t
	Message based Bottom Half Processor descriptor. More...

Macros
#define	BHP_MSG_BH_REQUEST   0x1539
	The message type to trigger Bottom Half Processing.

Functions
void	bhp_msg_init (bhp_msg_t *bhp_msg, bhp_cb_t cb, void *ctx)
	Init a Bottom Half Processor to be used with messages.
void	bhp_msg_isr_cb (void *bhp_msg_ctx)
	Message based Bottom Half Processor ISR callback To be called from ISR in order to trigger the Bottom Half Processor.
static void	bhp_msg_claim_thread (bhp_msg_t *bhp_msg, kernel_pid_t pid)
	Claim a thread with a message queue to be used as Bottom Half Processor.
static void	bhp_msg_handler (msg_t *msg)
	Handle a Bottom Half Processor message with type BHP_MSG_BH_REQUEST.

Macro Definition Documentation

BHP_MSG_BH_REQUEST

#define BHP_MSG_BH_REQUEST   0x1539

The message type to trigger Bottom Half Processing.

Definition at line 38 of file msg.h.

Function Documentation

bhp_msg_claim_thread()

static void bhp_msg_claim_thread ( bhp_msg_t *  bhp_msg, kernel_pid_t  pid  )

inlinestatic

Claim a thread with a message queue to be used as Bottom Half Processor.

Parameters

[in]	bhp_msg	The message based Bottom Half Processor descriptor
[in]	pid	PID of the target thread

Definition at line 81 of file msg.h.

bhp_msg_handler()

static void bhp_msg_handler ( msg_t *  msg )

inlinestatic

Handle a Bottom Half Processor message with type BHP_MSG_BH_REQUEST.

This function will call bhp_irq_handler internally.

Note

This function asserts that the message type is BHP_MSG_BH_REQUEST.

Parameters

[in]

msg

Pointer to the Bottom Half Processor message.

Definition at line 95 of file msg.h.

bhp_msg_init()

void bhp_msg_init	(	bhp_msg_t *	bhp_msg,
		bhp_cb_t	cb,
		void *	ctx
	)

Init a Bottom Half Processor to be used with messages.

Postcondition

the target PID is set to KERNEL_PID_UNDEF

Parameters

[in]	bhp_msg	The message based Bottom Half Processor descriptor
[in]	cb	Bottom Half Processor callback
[in]	ctx	Context of cb

bhp_msg_isr_cb()

void bhp_msg_isr_cb

(

void *

bhp_msg_ctx

)

Message based Bottom Half Processor ISR callback To be called from ISR in order to trigger the Bottom Half Processor.

This sends a message with type BHP_MSG_BH_REQUEST to the target thread, which should process the event accordingly by calling bhp_msg_handler.

Note

This function asserts that the target PID is valid. Therefore, make sure to call bhp_msg_claim_thread beforehand.

Parameters

[in]

bhp_msg_ctx

Pointer to the message based Bottom Half Processor (bhp_msg_t) Bottom Half Processor.