2025年12月 – ページ 2

タイムスライスなしのシンプルなタスクライブラリ。yield()を実行したときだけタスク切替する２プライオリティのラウンドロビン型スケジューリングを行う。休止状態からの起床時に優先度が一時的に高くなる。

【avr8_config.h】

/* Taskクラスを使う設定 */
#define CONFIG_TASK_USE 1
/* Taskスタックサイズ指定省略時のスタックサイズ */
#define CONFIG_TASK_STACK_SIZE 256

/* Taskクラスを使う設定 */

#define CONFIG_TASK_USE 1

/* Taskスタックサイズ指定省略時のスタックサイズ */

#define CONFIG_TASK_STACK_SIZE 256

【サンプルコード (Microchip Studio – Arduino風)】

/*
 * Task Sample Program
 *
 */
#include "avr8_task.h"

void task0(void *arg)
{
  (void)arg;
  uint32_t tick = Timer.us2tick(500000);
  while (1)
  {
    print("task0\n");
    Task::sleep(tick);
  }
}

void task1(void *arg)
{
  (void)arg;
  uint32_t tick = Timer.us2tick(500000);
  while (1)
  {
    print("task1\n");
    Task::sleep(tick);
  }
}

void setup(void)
{
  Task::start(task0);
  Task::start(task1);
}

void loop(void)
{
}

* Task Sample Program

#include "avr8_task.h"

void task0(void *arg)

{

(void)arg;

uint32_t tick = Timer.us2tick(500000);

while (1)

{

print("task0\n");

Task::sleep(tick);

}

void task1(void *arg)

{

(void)arg;

uint32_t tick = Timer.us2tick(500000);

while (1)

{

print("task1\n");

Task::sleep(tick);

}

void setup(void)

{

Task::start(task0);

Task::start(task1);

}

void loop(void)

{

}

【ライブラリ】

/*
  avr8_task.h - Task Library for Microchip AVR8 Series
 
  Copyright (c) 2025 Sasapea's Lab. All right reserved.
 
  This program is free software: you can redistribute it and/or
  modify it under the terms of the GNU General Public License as
  published by the Free Software Foundation, either version 3 of
  the License, or at your option) any later version.
 
  This program is distributed in the hope that it will be useful,
  but WITHOUT ANY WARRANTY; without even the implied warranty of
  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
  See the GNU General Public License for more details.
 
  You should have received a copy of the GNU General Public License
  along with this program. If not, see <https://www.gnu.org/licenses/>.
*/
#pragma once

#include <stddef.h>
#include <stdint.h>
#include <stdbool.h>
#include <setjmp.h>
#include "avr8_alarm.h"

#if CONFIG_TASK_USE

#define TASK_STACK_SIZE(n) ((n) + Task::TCB_SIZE)

class Task : public TimerClass
{
  public:

    typedef void (*func_t)(void *arg);

  protected:

    typedef struct tcb
    {
      struct tcb *next;
      jmp_buf context;
      void *alloc;
      void *arg;
      func_t start;
    } tcb_t;

    typedef struct
    {
      Alarm  alarm;
      sreg_t state;
      bool   retval;
    } ctrl_t;

    static void enqueue0(tcb_t *tcb);
    static void enqueue1(tcb_t *tcb);
    static tcb_t *dequeue(void);
    static void switching(void);
    static void dispatch(void);

  public:

    static const int TCB_SIZE = sizeof(tcb_t);

    static void begin(size_t size = TASK_STACK_SIZE(CONFIG_TASK_STACK_SIZE));
    static bool start(func_t func, void *arg = 0, int size = TASK_STACK_SIZE(CONFIG_TASK_STACK_SIZE), void *stack = 0);
    static void stop(void);
    static bool yield(void);
    static size_t current(void);
    static void sleep(int32_t tick, uint8_t busyLoop = 0);
    static void delay(uint32_t tick, uint8_t busyLoop = 0);

  private:

    static tcb_t *_disp;
    static tcb_t *_curr;
    static tcb_t *_head;
    static tcb_t *_tail[2];
    static size_t _used;
};

class Sync : protected Task
{
  public:

    Sync(void);
    bool sleep(int32_t timeout = -1);
    size_t wakeup(size_t task = 0);

  protected:

    bool sleep(ctrl_t& ctrl);
    static bool timeup(Alarm& alarm);

    tcb_t *_head;
    tcb_t *_tail;
};

class Mutex : protected Sync
{
  public:

    Mutex(void);
    bool lock(int32_t timeout = -1);
    void unlock(void);

  protected:

    size_t _owner;
    size_t _count;
};

class Sem : protected Sync
{
  public:

    Sem(size_t limit = (size_t)-1, size_t count = 0);
    bool wait(size_t count = 1, int32_t timeout = -1);
    void post(size_t count = 1);

  protected:

    size_t _limit;
    size_t _count;
    size_t _wait;
};

class Event : protected Sem
{
  protected:

    Event(void);
    bool wait(int32_t timeout = -1);
    void signal(void);
};
#endif

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avr8_task.h - Task Library for Microchip AVR8 Series

This program is free software: you can redistribute it and/or

modify it under the terms of the GNU General Public License as

published by the Free Software Foundation, either version 3 of

the License, or at your option) any later version.

This program is distributed in the hope that it will be useful,

but WITHOUT ANY WARRANTY; without even the implied warranty of

MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.

See the GNU General Public License for more details.

You should have received a copy of the GNU General Public License

along with this program. If not, see <https://www.gnu.org/licenses/>.

#pragma once

#include <stddef.h>

#include <stdint.h>

#include <stdbool.h>

#include <setjmp.h>

#include "avr8_alarm.h"

#if CONFIG_TASK_USE

#define TASK_STACK_SIZE(n) ((n) + Task::TCB_SIZE)

class Task : public TimerClass

{

public:

typedef void (*func_t)(void *arg);

protected:

typedef struct tcb

{

struct tcb *next;

jmp_buf context;

void *alloc;

void *arg;

func_t start;

} tcb_t;

typedef struct

{

Alarm alarm;

sreg_t state;

bool retval;

} ctrl_t;

static void enqueue0(tcb_t *tcb);

static void enqueue1(tcb_t *tcb);

static tcb_t *dequeue(void);

static void switching(void);

static void dispatch(void);

public:

static const int TCB_SIZE = sizeof(tcb_t);

static void begin(size_t size = TASK_STACK_SIZE(CONFIG_TASK_STACK_SIZE));

static bool start(func_t func, void *arg = 0, int size = TASK_STACK_SIZE(CONFIG_TASK_STACK_SIZE), void *stack = 0);

static void stop(void);

static bool yield(void);

static size_t current(void);

static void sleep(int32_t tick, uint8_t busyLoop = 0);

static void delay(uint32_t tick, uint8_t busyLoop = 0);

private:

static tcb_t *_disp;

static tcb_t *_curr;

static tcb_t *_head;

static tcb_t *_tail[2];

static size_t _used;

};

class Sync : protected Task

{

public:

Sync(void);

bool sleep(int32_t timeout = -1);

size_t wakeup(size_t task = 0);

protected:

bool sleep(ctrl_t& ctrl);

static bool timeup(Alarm& alarm);

tcb_t *_head;

tcb_t *_tail;

};

class Mutex : protected Sync

{

public:

Mutex(void);

bool lock(int32_t timeout = -1);

void unlock(void);

protected:

size_t _owner;

size_t _count;

};

class Sem : protected Sync

{

public:

Sem(size_t limit = (size_t)-1, size_t count = 0);

bool wait(size_t count = 1, int32_t timeout = -1);

void post(size_t count = 1);

protected:

size_t _limit;

size_t _count;

size_t _wait;

};

class Event : protected Sem

{

protected:

Event(void);

bool wait(int32_t timeout = -1);

void signal(void);

};

#endif

/*
  avr8_task.cpp - Task Library for Microchip AVR8 Series
 
  Copyright (c) 2025 Sasapea's Lab. All right reserved.
 
  This program is free software: you can redistribute it and/or
  modify it under the terms of the GNU General Public License as
  published by the Free Software Foundation, either version 3 of
  the License, or at your option) any later version.
 
  This program is distributed in the hope that it will be useful,
  but WITHOUT ANY WARRANTY; without even the implied warranty of
  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
  See the GNU General Public License for more details.
 
  You should have received a copy of the GNU General Public License
  along with this program. If not, see <https://www.gnu.org/licenses/>.
*/
#include <stdlib.h>
#if !defined(alloca)
  #include <alloca.h>
#endif
#include "avr8_task.h"

#if CONFIG_TASK_USE

Task::tcb_t *Task::_disp;
Task::tcb_t *Task::_curr;
Task::tcb_t *Task::_head;
Task::tcb_t *Task::_tail[];
size_t       Task::_used;

void Task::begin(size_t size)
{
  /* Registration of main task */
  static tcb_t tcb;
  _curr = &tcb;
  _used = size;
  AlarmTimer.begin();
}

bool Task::start(func_t func, void *arg, int size, void *stack)
{
  tcb_t *tcb;
  if (size < 0)
  {
    /* Use the current stack area */
    size_t n = - size;
    size  = _used;
    stack = 0;
    _used += n;
  }
  else if (stack)
  {
    /* Set the stack area to the variable area */
    size  = (char *)&tcb - (char *)stack - size + sizeof(*tcb);
    stack = 0;
  }
  else
  {
    /* Dynamically allocate stack area */
    stack = malloc(size);
    if (!stack)
      return false;
    size = (char *)&tcb - (char *)stack - size + sizeof(*tcb);
  }
  tcb = (tcb_t *)alloca(size);
  tcb->alloc = stack;
  tcb->arg   = arg;
  tcb->start = func;
  enqueue0(tcb);
  if (setjmp(tcb->context))
  {
    _curr = _disp;
    _curr->start(_curr->arg);
    stop();
  }
  return true;
}

void Task::stop(void)
{
  if (_curr->start)
  {
    if (_curr->alloc)
      free(_curr->alloc);
    dispatch();
  }
}

void Task::enqueue0(tcb_t *tcb)
{
  sreg_t state = disableAndSaveInterrupts();
  if (_tail[0])
  {
    tcb->next = _tail[0]->next;
    _tail[0]  = (_tail[0]->next = tcb);
  }
  else
  {
    tcb->next = _head;
    _tail[0]  = (_head = tcb);
  }
  restoreInterrupts(state);
}

void Task::enqueue1(tcb_t *tcb)
{
  sreg_t state = disableAndSaveInterrupts();
  (_tail[1] = *(_tail[1] ? &_tail[1]->next : (_tail[0] ? &_tail[0]->next : &_head)) = tcb)->next = 0;
  restoreInterrupts(state);
}

Task::tcb_t *Task::dequeue(void)
{
  tcb_t *tcb;
  sreg_t state = disableAndSaveInterrupts();
  if ((tcb = _head))
  {
    if (_head == _tail[0])
      _tail[0] = 0;
    else if (_head == _tail[1])
      _tail[1] = 0;
    _head = _head->next;
  }
  restoreInterrupts(state);
  return tcb;
}

size_t Task::current(void)
{
  return (size_t)_curr;
}

bool Task::yield(void)
{
  AlarmTimer.handle();
  enqueue1(_curr);
  switching();
  return !_curr->start;
}

void Task::switching(void)
{
  if (!setjmp(_curr->context))
    dispatch();
  _curr = _disp;
}

void Task::dispatch(void)
{
  while (1)
  {
    if ((_disp = dequeue()))
      longjmp(_disp->context, 1);
    idle();
    AlarmTimer.handle();
  }
}

void Task::sleep(int32_t tick, uint8_t busyLoop)
{
  uint32_t t = Timer.read();
  if (tick > busyLoop)
  {
    Sync sync;
    sync.sleep(tick -= busyLoop);
    t += tick;
  }
  if (busyLoop)
  {
    while (Timer.read() - t < busyLoop)
      continue;
  }
}

void Task::delay(uint32_t tick, uint8_t busyLoop)
{
  uint32_t t = Timer.read();
  if (tick > busyLoop)
  {
    tick -= busyLoop;
    while (Timer.read() - t < tick)
      yield();
    t += tick;
  }
  if (busyLoop)
  {
    while (Timer.read() - t < busyLoop)
      continue;
  }
}

Sync::Sync(void) : _head(0), _tail(0)
{
}

bool Sync::timeup(Alarm& alarm)
{
  if (((Sync *)alarm.param(0))->wakeup((size_t)alarm.param(1)))
    *(bool *)alarm.param(2) = false;
  return false;
}

bool Sync::sleep(ctrl_t& ctrl)
{
  tcb_t *tcb = (tcb_t *)current();
  (_tail = *(_tail ? &_tail->next : &_head) = tcb)->next = 0;
  restoreInterrupts(ctrl.state);
  ctrl.alarm.param(0, this);
  ctrl.alarm.param(1, tcb);
  ctrl.alarm.param(2, &ctrl.retval);
  ctrl.alarm.handler(timeup);
  AlarmTimer.start(ctrl.alarm);
  switching();
  return ctrl.retval;
}

bool Sync::sleep(int32_t timeout)
{
  if (timeout == 0)
    return false;
  ctrl_t ctrl;
  ctrl.alarm.interval(timeout);
  ctrl.retval = true;
  ctrl.state  = disableAndSaveInterrupts();
  return sleep(ctrl);
}

size_t Sync::wakeup(size_t task)
{
  tcb_t *tcb = 0;
  sreg_t state = disableAndSaveInterrupts();
  if (task)
  {
    for (tcb_t **p = &_head; *p; p = &(*p)->next)
    {
      if (*p == (tcb_t *)task)
      {
        if (!(*p = (*p)->next))
          _tail = (p == &_head ? 0 : (tcb_t *)p);
        tcb = (tcb_t *)task;
        break;
      }
    }
  }
  else
    _head = ((tcb = _head) != _tail ? _head->next : _tail = 0);
  restoreInterrupts(state);
  if (tcb)
  {
    AlarmTimer.cancel(1, tcb);
    enqueue0(tcb);
  }
  return (size_t)tcb;
}

Mutex::Mutex(void) : _owner(0)
{
}

bool Mutex::lock(int32_t timeout)
{
  ctrl_t ctrl;
  ctrl.alarm.interval(timeout);
  ctrl.retval = true;
  ctrl.state  = disableAndSaveInterrupts();
  size_t task = current();
  if (!_owner)
  {
    _owner = task;
    _count = 1;
  }
  else if (_owner == task)
    ++_count;
  else if (timeout == 0)
    ctrl.retval = false;
  else
    return sleep(ctrl);
  restoreInterrupts(ctrl.state);
  return ctrl.retval;
}

void Mutex::unlock(void)
{
  sreg_t state = disableAndSaveInterrupts();
  if (_owner == current())
  {
    if (--_count == 0)
    {
      _owner = wakeup();
      _count = 1;
    }
  }
  restoreInterrupts(state);
}

Sem::Sem(size_t limit, size_t count) : _limit(limit), _count(count), _wait(0)
{
}

bool Sem::wait(size_t count, int32_t timeout)
{
  ctrl_t ctrl;
  ctrl.alarm.interval(timeout);
  ctrl.retval = true;
  ctrl.state  = disableAndSaveInterrupts();
  if ((count == 0) || (count > _limit))
    ctrl.retval = false;
  else if (!_wait && (_count >= count))
    _count -= count;
  else if (timeout == 0)
    ctrl.retval = false;
  else
  {
    ++_wait;
    ((tcb_t *)current())->arg = (void *)count;
    sleep(ctrl);
    disableAndSaveInterrupts();
    --_wait;
    while (_head)
    {
      count = (size_t)_head->arg;
      if (_count < count)
        break;
      _count -= count;
      wakeup();
    }
  }
  restoreInterrupts(ctrl.state);
  return ctrl.retval;
}

void Sem::post(size_t count)
{
  sreg_t state = disableAndSaveInterrupts();
  if (count && (count + _count <= _limit))
  {
    _count += count;
    if (_head)
    {
      count = (size_t)_head->arg;
      if (_count >= count)
      {
        _count -= count;
        wakeup();
      }
    }
  }
  restoreInterrupts(state);
}

Event::Event(void) : Sem(1)
{
}

bool Event::wait(int32_t timeout)
{
  return Sem::wait(1, timeout);
}

void Event::signal(void)
{
  Sem::post();
}

#endif

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avr8_task.cpp - Task Library for Microchip AVR8 Series

This program is free software: you can redistribute it and/or

modify it under the terms of the GNU General Public License as

published by the Free Software Foundation, either version 3 of

the License, or at your option) any later version.

This program is distributed in the hope that it will be useful,

but WITHOUT ANY WARRANTY; without even the implied warranty of

MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.

See the GNU General Public License for more details.

You should have received a copy of the GNU General Public License

along with this program. If not, see <https://www.gnu.org/licenses/>.

#include <stdlib.h>

#if !defined(alloca)

#include <alloca.h>

#endif

#include "avr8_task.h"

#if CONFIG_TASK_USE

Task::tcb_t *Task::_disp;

Task::tcb_t *Task::_curr;

Task::tcb_t *Task::_head;

Task::tcb_t *Task::_tail[];

size_t Task::_used;

void Task::begin(size_t size)

{

/* Registration of main task */

static tcb_t tcb;

_curr = &tcb;

_used = size;

AlarmTimer.begin();

}

bool Task::start(func_t func, void *arg, int size, void *stack)

{

tcb_t *tcb;

if (size < 0)

{

/* Use the current stack area */

size_t n = - size;

size = _used;

stack = 0;

_used += n;

}

else if (stack)

{

/* Set the stack area to the variable area */

size = (char *)&tcb - (char *)stack - size + sizeof(*tcb);

stack = 0;

}

else

{

/* Dynamically allocate stack area */

stack = malloc(size);

if (!stack)

return false;

size = (char *)&tcb - (char *)stack - size + sizeof(*tcb);

}

tcb = (tcb_t *)alloca(size);

tcb->alloc = stack;

tcb->arg = arg;

tcb->start = func;

enqueue0(tcb);

if (setjmp(tcb->context))

{

_curr = _disp;

_curr->start(_curr->arg);

stop();

}

return true;

}

void Task::stop(void)

{

if (_curr->start)

{

if (_curr->alloc)

free(_curr->alloc);

dispatch();

}

void Task::enqueue0(tcb_t *tcb)

{

sreg_t state = disableAndSaveInterrupts();

if (_tail[0])

{

tcb->next = _tail[0]->next;

_tail[0] = (_tail[0]->next = tcb);

}

else

{

tcb->next = _head;

_tail[0] = (_head = tcb);

}

restoreInterrupts(state);

}

void Task::enqueue1(tcb_t *tcb)

{

sreg_t state = disableAndSaveInterrupts();

(_tail[1] = *(_tail[1] ? &_tail[1]->next : (_tail[0] ? &_tail[0]->next : &_head)) = tcb)->next = 0;

restoreInterrupts(state);

}

Task::tcb_t *Task::dequeue(void)

{

tcb_t *tcb;

sreg_t state = disableAndSaveInterrupts();

if ((tcb = _head))

{

if (_head == _tail[0])

_tail[0] = 0;

else if (_head == _tail[1])

_tail[1] = 0;

_head = _head->next;

}

restoreInterrupts(state);

return tcb;

}

size_t Task::current(void)

{

return (size_t)_curr;

}

bool Task::yield(void)

{

AlarmTimer.handle();

enqueue1(_curr);

switching();

return !_curr->start;

}

void Task::switching(void)

{

if (!setjmp(_curr->context))

dispatch();

_curr = _disp;

}

void Task::dispatch(void)

{

while (1)

{

if ((_disp = dequeue()))

longjmp(_disp->context, 1);

idle();

AlarmTimer.handle();

}

void Task::sleep(int32_t tick, uint8_t busyLoop)

{

uint32_t t = Timer.read();

if (tick > busyLoop)

{

Sync sync;

sync.sleep(tick -= busyLoop);

t += tick;

}

if (busyLoop)

{

while (Timer.read() - t < busyLoop)

continue;

}

void Task::delay(uint32_t tick, uint8_t busyLoop)

{

uint32_t t = Timer.read();

if (tick > busyLoop)

{

tick -= busyLoop;

while (Timer.read() - t < tick)

yield();

t += tick;

}

if (busyLoop)

{

while (Timer.read() - t < busyLoop)

continue;

}

Sync::Sync(void) : _head(0), _tail(0)

{

}

bool Sync::timeup(Alarm& alarm)

{

if (((Sync *)alarm.param(0))->wakeup((size_t)alarm.param(1)))

*(bool *)alarm.param(2) = false;

return false;

}

bool Sync::sleep(ctrl_t& ctrl)

{

tcb_t *tcb = (tcb_t *)current();

(_tail = *(_tail ? &_tail->next : &_head) = tcb)->next = 0;

restoreInterrupts(ctrl.state);

ctrl.alarm.param(0, this);

ctrl.alarm.param(1, tcb);

ctrl.alarm.param(2, &ctrl.retval);

ctrl.alarm.handler(timeup);

AlarmTimer.start(ctrl.alarm);

switching();

return ctrl.retval;

}

bool Sync::sleep(int32_t timeout)

{

if (timeout == 0)

return false;

ctrl_t ctrl;

ctrl.alarm.interval(timeout);

ctrl.retval = true;

ctrl.state = disableAndSaveInterrupts();

return sleep(ctrl);

}

size_t Sync::wakeup(size_t task)

{

tcb_t *tcb = 0;

sreg_t state = disableAndSaveInterrupts();

if (task)

{

for (tcb_t **p = &_head; *p; p = &(*p)->next)

{

if (*p == (tcb_t *)task)

{

if (!(*p = (*p)->next))

_tail = (p == &_head ? 0 : (tcb_t *)p);

tcb = (tcb_t *)task;

break;

}

else

_head = ((tcb = _head) != _tail ? _head->next : _tail = 0);

restoreInterrupts(state);

if (tcb)

{

AlarmTimer.cancel(1, tcb);

enqueue0(tcb);

}

return (size_t)tcb;

}

Mutex::Mutex(void) : _owner(0)

{

}

bool Mutex::lock(int32_t timeout)

{

ctrl_t ctrl;

ctrl.alarm.interval(timeout);

ctrl.retval = true;

ctrl.state = disableAndSaveInterrupts();

size_t task = current();

if (!_owner)

{

_owner = task;

_count = 1;

}

else if (_owner == task)

++_count;

else if (timeout == 0)

ctrl.retval = false;

else

return sleep(ctrl);

restoreInterrupts(ctrl.state);

return ctrl.retval;

}

void Mutex::unlock(void)

{

sreg_t state = disableAndSaveInterrupts();

if (_owner == current())

{

if (--_count == 0)

{

_owner = wakeup();

_count = 1;

}

restoreInterrupts(state);

}

Sem::Sem(size_t limit, size_t count) : _limit(limit), _count(count), _wait(0)

{

}

bool Sem::wait(size_t count, int32_t timeout)

{

ctrl_t ctrl;

ctrl.alarm.interval(timeout);

ctrl.retval = true;

ctrl.state = disableAndSaveInterrupts();

if ((count == 0) || (count > _limit))

ctrl.retval = false;

else if (!_wait && (_count >= count))

_count -= count;

else if (timeout == 0)

ctrl.retval = false;

else

{

++_wait;

((tcb_t *)current())->arg = (void *)count;

sleep(ctrl);

disableAndSaveInterrupts();

--_wait;

while (_head)

{

count = (size_t)_head->arg;

if (_count < count)

break;

_count -= count;

wakeup();

}

restoreInterrupts(ctrl.state);

return ctrl.retval;

}

void Sem::post(size_t count)

{

sreg_t state = disableAndSaveInterrupts();

if (count && (count + _count <= _limit))

{

_count += count;

if (_head)

{

count = (size_t)_head->arg;

if (_count >= count)

{

_count -= count;

wakeup();

}

restoreInterrupts(state);

}

Event::Event(void) : Sem(1)

{

}

bool Event::wait(int32_t timeout)

{

return Sem::wait(1, timeout);

}

void Event::signal(void)

{

Sem::post();

}

#endif

月: 2025年12月

Microchip AVR8 用のライブラリを自作する。(TASK)