368 lines
10 KiB
C
368 lines
10 KiB
C
/*
|
|
* Copyright (c) 2004, Swedish Institute of Computer Science.
|
|
* All rights reserved.
|
|
*
|
|
* Redistribution and use in source and binary forms, with or without
|
|
* modification, are permitted provided that the following conditions
|
|
* are met:
|
|
* 1. Redistributions of source code must retain the above copyright
|
|
* notice, this list of conditions and the following disclaimer.
|
|
* 2. Redistributions in binary form must reproduce the above copyright
|
|
* notice, this list of conditions and the following disclaimer in the
|
|
* documentation and/or other materials provided with the distribution.
|
|
* 3. Neither the name of the Institute nor the names of its contributors
|
|
* may be used to endorse or promote products derived from this software
|
|
* without specific prior written permission.
|
|
*
|
|
* THIS SOFTWARE IS PROVIDED BY THE INSTITUTE AND CONTRIBUTORS ``AS IS'' AND
|
|
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
|
|
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
|
|
* ARE DISCLAIMED. IN NO EVENT SHALL THE INSTITUTE OR CONTRIBUTORS BE LIABLE
|
|
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
|
|
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
|
|
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
|
|
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
|
|
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
|
|
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
|
|
* SUCH DAMAGE.
|
|
*
|
|
* This file is part of the Contiki operating system.
|
|
*
|
|
* Author: Adam Dunkels <adam@sics.se>
|
|
*
|
|
* $Id: mt.h,v 1.3 2006/09/26 20:59:51 adamdunkels Exp $
|
|
*/
|
|
|
|
/** \addtogroup sys
|
|
* @{
|
|
*/
|
|
|
|
/**
|
|
* \defgroup mt Multi-threading library
|
|
*
|
|
* The event driven Contiki kernel does not provide multi-threading
|
|
* by itself - instead, preemptive multi-threading is implemented
|
|
* as a library that optionally can be linked with applications. This
|
|
* library constists of two parts: a platform independent part, which is
|
|
* the same for all platforms on which Contiki runs, and a platform
|
|
* specific part, which must be implemented specifically for the
|
|
* platform that the multi-threading library should run.
|
|
*
|
|
* @{
|
|
*/
|
|
|
|
/**
|
|
* \defgroup mtarch Architecture support for multi-threading
|
|
* @{
|
|
*
|
|
* The Contiki multi-threading library requires some architecture
|
|
* specific support for seting up and switching stacks. This support
|
|
* requires three stack manipulation functions to be implemented:
|
|
* mtarch_start(), which sets up the stack frame for a new thread,
|
|
* mtarch_exec(), which switches in the stack of a thread, and
|
|
* mtarch_yield(), which restores the kernel stack from a thread's
|
|
* stack. Additionally, two functions for controlling the preemption
|
|
* (if any) must be implemented: mtarch_preemption_start() and
|
|
* mtarch_preemption_stop(). If no preemption is used, these functions
|
|
* can be implemented as empty functions. Finally, the function
|
|
* mtarch_init() is called by mt_init(), and can be used for
|
|
* initalization of timer interrupts, or any other mechanisms required
|
|
* for correct operation of the architecture specific support funcions.
|
|
*
|
|
*/
|
|
|
|
/**
|
|
* \file
|
|
* Header file for the preemptive multitasking library for Contiki.
|
|
* \author
|
|
* Adam Dunkels <adam@sics.se>
|
|
*
|
|
*/
|
|
#ifndef __MT_H__
|
|
#define __MT_H__
|
|
|
|
#include "contiki.h"
|
|
|
|
|
|
/**
|
|
* An opaque structure that is used for holding the state of a thread.
|
|
*
|
|
* The structure should be defined in the "mtarch.h" file. This
|
|
* structure typically holds the entire stack for the thread.
|
|
*/
|
|
struct mtarch_thread;
|
|
|
|
/**
|
|
* Initialize the architecture specific support functions for the
|
|
* multi-thread library.
|
|
*
|
|
* This function is implemented by the architecture specific functions
|
|
* for the multi-thread library and is called by the mt_init()
|
|
* function as part of the initialization of the library. The
|
|
* mtarch_init() function can be used for, e.g., starting preemtion
|
|
* timers or other architecture specific mechanisms required for the
|
|
* operation of the library.
|
|
*/
|
|
void mtarch_init(void);
|
|
|
|
/**
|
|
* Uninstall library and clean up.
|
|
*
|
|
*/
|
|
void mtarch_remove(void);
|
|
|
|
/**
|
|
* Setup the stack frame for a thread that is being started.
|
|
*
|
|
* This function is called by the mt_start() function in order to set
|
|
* up the architecture specific stack of the thread to be started.
|
|
*
|
|
* \param thread A pointer to a struct mtarch_thread for the thread to
|
|
* be started.
|
|
*
|
|
* \param function A pointer to the function that the thread will
|
|
* start executing the first time it is scheduled to run.
|
|
*
|
|
* \param data A pointer to the argument that the function should be
|
|
* passed.
|
|
*/
|
|
void mtarch_start(struct mtarch_thread *thread,
|
|
void (* function)(void *data),
|
|
void *data);
|
|
|
|
/**
|
|
* Yield the processor.
|
|
*
|
|
* This function is called by the mt_yield() function, which is called
|
|
* from the running thread in order to give up the processor.
|
|
*
|
|
*/
|
|
void mtarch_yield(void);
|
|
|
|
/**
|
|
* Start executing a thread.
|
|
*
|
|
* This function is called from mt_exec() and the purpose of the
|
|
* function is to start execution of the thread. The function should
|
|
* switch in the stack of the thread, and does not return until the
|
|
* thread has explicitly yielded (using mt_yield()) or until it is
|
|
* preempted.
|
|
*
|
|
*/
|
|
void mtarch_exec(struct mtarch_thread *thread);
|
|
|
|
|
|
void mtarch_pstart(void);
|
|
void mtarch_pstop(void);
|
|
|
|
/** @} */
|
|
|
|
|
|
#include "mtarch.h"
|
|
|
|
struct mt_thread {
|
|
int state;
|
|
process_event_t *evptr;
|
|
process_data_t *dataptr;
|
|
struct mtarch_thread thread;
|
|
};
|
|
|
|
/**
|
|
* No error.
|
|
*
|
|
* \hideinitializer
|
|
*/
|
|
#define MT_OK 1
|
|
|
|
/**
|
|
* Initializes the multithreading library.
|
|
*
|
|
*/
|
|
void mt_init(void);
|
|
|
|
/**
|
|
* Uninstalls library and cleans up.
|
|
*
|
|
*/
|
|
void mt_remove(void);
|
|
|
|
|
|
/**
|
|
* Starts a multithreading thread.
|
|
*
|
|
* \param thread Pointer to an mt_thread struct that must have been
|
|
* previously allocated by the caller.
|
|
*
|
|
* \param function A pointer to the entry function of the thread that is
|
|
* to be set up.
|
|
*
|
|
* \param data A pointer that will be passed to the entry function.
|
|
*
|
|
*/
|
|
void mt_start(struct mt_thread *thread, void (* function)(void *), void *data);
|
|
|
|
/**
|
|
* Execute parts of a thread.
|
|
*
|
|
* This function is called by a Contiki process and runs a
|
|
* thread. The function does not return until the thread has yielded,
|
|
* or is preempted.
|
|
*
|
|
* \note The thread must first be initialized with the mt_init() function.
|
|
*
|
|
* \param thread A pointer to a struct mt_thread block that must be
|
|
* allocated by the caller.
|
|
*
|
|
*/
|
|
void mt_exec(struct mt_thread *thread);
|
|
|
|
/**
|
|
* Post an event to a thread.
|
|
*
|
|
* This function posts an event to a thread. The thread will be
|
|
* scheduled if the thread currently is waiting for the posted event
|
|
* number. If the thread is not waiting for the event, this function
|
|
* does nothing.
|
|
*
|
|
* \note The thread must first be initialized with the mt_init() function.
|
|
*
|
|
* \param thread A pointer to a struct mt_thread block that must be
|
|
* allocated by the caller.
|
|
*
|
|
* \param s The event that is posted to the thread.
|
|
*
|
|
* \param data An opaque pointer to a user specified structure
|
|
* containing additonal information, or NULL if no additional
|
|
* information is needed.
|
|
*/
|
|
/*void mt_exec_event(struct mt_thread *thread, process_event_t s,
|
|
process_data_t data);*/
|
|
|
|
/**
|
|
* Voluntarily give up the processor.
|
|
*
|
|
* This function is called by a running thread in order to give up
|
|
* control of the CPU.
|
|
*
|
|
*/
|
|
void mt_yield(void);
|
|
|
|
/**
|
|
* Post an event to another process.
|
|
*
|
|
* This function is called by a running thread and will emit a signal
|
|
* to another Contiki process. This will cause the currently executing
|
|
* thread to yield.
|
|
*
|
|
* \param p The process receiving the signal, or PROCESS_BROADCAST
|
|
* for a broadcast event.
|
|
*
|
|
* \param ev The event to be posted.
|
|
*
|
|
* \param data A pointer to a message that is to be delivered together
|
|
* with the signal.
|
|
*
|
|
*/
|
|
/*void mt_post(struct process *p, process_event_t ev, process_data_t data);*/
|
|
|
|
/**
|
|
* Block and wait for an event to occur.
|
|
*
|
|
* This function can be called by a running thread in order to block
|
|
* and wait for an event. The function returns when an event has
|
|
* occured. The event number and the associated data are placed in the
|
|
* variables pointed to by the function arguments.
|
|
*
|
|
* \param ev A pointer to a process_event_t variable. The variable
|
|
* will be filled with the number event that woke the thread.
|
|
*
|
|
* \param data A pointer to a process_data_t variable. The variable
|
|
* will be filled with the data associated with the event that woke
|
|
* the thread.
|
|
*
|
|
*/
|
|
/*void mt_wait(process_event_t *ev, process_data_t *data);*/
|
|
|
|
/**
|
|
* Exit a thread.
|
|
*
|
|
* This function is called from within an executing thread in order to
|
|
* exit the thread. The function never returns.
|
|
*
|
|
*/
|
|
void mt_exit(void);
|
|
|
|
#if 0
|
|
/**
|
|
* \defgroup mtp Multi-threading library convenience functions
|
|
* @{
|
|
*
|
|
* The Contiki multi-threading library has an interface that might be
|
|
* hard to use. Therefore, the mtp module provides a simpler
|
|
* interface.
|
|
*
|
|
* Example:
|
|
\code
|
|
static void
|
|
example_thread_code(void *data)
|
|
{
|
|
while(1) {
|
|
printf("Test\n");
|
|
mt_yield();
|
|
}
|
|
}
|
|
MTP(example_thread, "Example thread", p1, t1, t1_idle);
|
|
|
|
int
|
|
main(int argc, char *argv[])
|
|
{
|
|
mtp_start(&example_thread, example_thread_code, NULL);
|
|
}
|
|
\endcode
|
|
*
|
|
*/
|
|
|
|
|
|
/**
|
|
* Declare a multithreaded process.
|
|
*
|
|
* This macro is used to declare a multithreaded process.
|
|
*
|
|
* \hideinitializer
|
|
*/
|
|
#define MT_PROCESS(name, strname) \
|
|
extern struct mt_process name##mt_process; \
|
|
struct process name = { NULL, strname, mt_process_thread }; \
|
|
static struct mt_process thread = {&name}
|
|
|
|
struct mt_process {
|
|
struct process *p;
|
|
struct mt_thread t;
|
|
};
|
|
|
|
/**
|
|
* Start a thread.
|
|
*
|
|
* This function starts the process in which the thread is to run, and
|
|
* also sets up the thread to run within the process. The function
|
|
* should be passed variable names declared with the MTP() macro.
|
|
*
|
|
* \param t A pointer to a thread structure previously declared with MTP().
|
|
*
|
|
* \param function A pointer to the function that the thread should
|
|
* start executing.
|
|
*
|
|
* \param data A pointer that the function should be passed when first
|
|
* invocated.
|
|
*/
|
|
void mtp_start(struct mt_process *p,
|
|
void (* function)(void *), void *data);
|
|
|
|
void mtp_exit(void);
|
|
void mtp_eventhandler(process_event_t ev, process_data_t data);
|
|
|
|
/** @} */
|
|
#endif /* 0 */
|
|
/** @} */
|
|
/** @} */
|
|
#endif /* __MT_H__ */
|