rt-thread/src/timer.c

714 lines
19 KiB
C

/*
* File : timer.c
* This file is part of RT-Thread RTOS
* COPYRIGHT (C) 2006 - 2012, RT-Thread Development Team
*
* 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 2 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, write to the Free Software Foundation, Inc.,
* 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
*
* Change Logs:
* Date Author Notes
* 2006-03-12 Bernard first version
* 2006-04-29 Bernard implement thread timer
* 2006-06-04 Bernard implement rt_timer_control
* 2006-08-10 Bernard fix the periodic timer bug
* 2006-09-03 Bernard implement rt_timer_detach
* 2009-11-11 LiJin add soft timer
* 2010-05-12 Bernard fix the timer check bug.
* 2010-11-02 Charlie re-implement tick overflow issue
* 2012-12-15 Bernard fix the next timeout issue in soft timer
* 2014-07-12 Bernard does not lock scheduler when invoking soft-timer
* timeout function.
*/
#include <rtthread.h>
#include <rthw.h>
/* hard timer list */
static rt_list_t rt_timer_list[RT_TIMER_SKIP_LIST_LEVEL];
#ifdef RT_USING_TIMER_SOFT
#ifndef RT_TIMER_THREAD_STACK_SIZE
#define RT_TIMER_THREAD_STACK_SIZE 512
#endif
#ifndef RT_TIMER_THREAD_PRIO
#define RT_TIMER_THREAD_PRIO 0
#endif
/* soft timer list */
static rt_list_t rt_soft_timer_list[RT_TIMER_SKIP_LIST_LEVEL];
static struct rt_thread timer_thread;
ALIGN(RT_ALIGN_SIZE)
static rt_uint8_t timer_thread_stack[RT_TIMER_THREAD_STACK_SIZE];
#endif
#ifdef RT_USING_HOOK
extern void (*rt_object_take_hook)(struct rt_object *object);
extern void (*rt_object_put_hook)(struct rt_object *object);
static void (*rt_timer_timeout_hook)(struct rt_timer *timer);
/**
* @addtogroup Hook
*/
/**@{*/
/**
* This function will set a hook function, which will be invoked when timer
* is timeout.
*
* @param hook the hook function
*/
void rt_timer_timeout_sethook(void (*hook)(struct rt_timer *timer))
{
rt_timer_timeout_hook = hook;
}
/**@}*/
#endif
static void _rt_timer_init(rt_timer_t timer,
void (*timeout)(void *parameter),
void *parameter,
rt_tick_t time,
rt_uint8_t flag)
{
int i;
/* set flag */
timer->parent.flag = flag;
/* set deactivated */
timer->parent.flag &= ~RT_TIMER_FLAG_ACTIVATED;
timer->timeout_func = timeout;
timer->parameter = parameter;
timer->timeout_tick = 0;
timer->init_tick = time;
/* initialize timer list */
for (i = 0; i < RT_TIMER_SKIP_LIST_LEVEL; i++)
{
rt_list_init(&(timer->row[i]));
}
}
/* the fist timer always in the last row */
static rt_tick_t rt_timer_list_next_timeout(rt_list_t timer_list[])
{
struct rt_timer *timer;
if (rt_list_isempty(&timer_list[RT_TIMER_SKIP_LIST_LEVEL - 1]))
return RT_TICK_MAX;
timer = rt_list_entry(timer_list[RT_TIMER_SKIP_LIST_LEVEL - 1].next,
struct rt_timer, row[RT_TIMER_SKIP_LIST_LEVEL - 1]);
return timer->timeout_tick;
}
rt_inline void _rt_timer_remove(rt_timer_t timer)
{
int i;
for (i = 0; i < RT_TIMER_SKIP_LIST_LEVEL; i++)
{
rt_list_remove(&timer->row[i]);
}
}
#if RT_DEBUG_TIMER
static int rt_timer_count_height(struct rt_timer *timer)
{
int i, cnt = 0;
for (i = 0; i < RT_TIMER_SKIP_LIST_LEVEL; i++)
{
if (!rt_list_isempty(&timer->row[i]))
cnt++;
}
return cnt;
}
void rt_timer_dump(rt_list_t timer_heads[])
{
rt_list_t *list;
for (list = timer_heads[RT_TIMER_SKIP_LIST_LEVEL - 1].next;
list != &timer_heads[RT_TIMER_SKIP_LIST_LEVEL - 1];
list = list->next)
{
struct rt_timer *timer = rt_list_entry(list,
struct rt_timer,
row[RT_TIMER_SKIP_LIST_LEVEL - 1]);
rt_kprintf("%d", rt_timer_count_height(timer));
}
rt_kprintf("\n");
}
#endif
/**
* @addtogroup Clock
*/
/**@{*/
/**
* This function will initialize a timer, normally this function is used to
* initialize a static timer object.
*
* @param timer the static timer object
* @param name the name of timer
* @param timeout the timeout function
* @param parameter the parameter of timeout function
* @param time the tick of timer
* @param flag the flag of timer
*/
void rt_timer_init(rt_timer_t timer,
const char *name,
void (*timeout)(void *parameter),
void *parameter,
rt_tick_t time,
rt_uint8_t flag)
{
/* timer check */
RT_ASSERT(timer != RT_NULL);
/* timer object initialization */
rt_object_init((rt_object_t)timer, RT_Object_Class_Timer, name);
_rt_timer_init(timer, timeout, parameter, time, flag);
}
RTM_EXPORT(rt_timer_init);
/**
* This function will detach a timer from timer management.
*
* @param timer the static timer object
*
* @return the operation status, RT_EOK on OK; RT_ERROR on error
*/
rt_err_t rt_timer_detach(rt_timer_t timer)
{
register rt_base_t level;
/* timer check */
RT_ASSERT(timer != RT_NULL);
/* disable interrupt */
level = rt_hw_interrupt_disable();
_rt_timer_remove(timer);
/* enable interrupt */
rt_hw_interrupt_enable(level);
rt_object_detach((rt_object_t)timer);
return -RT_EOK;
}
RTM_EXPORT(rt_timer_detach);
#ifdef RT_USING_HEAP
/**
* This function will create a timer
*
* @param name the name of timer
* @param timeout the timeout function
* @param parameter the parameter of timeout function
* @param time the tick of timer
* @param flag the flag of timer
*
* @return the created timer object
*/
rt_timer_t rt_timer_create(const char *name,
void (*timeout)(void *parameter),
void *parameter,
rt_tick_t time,
rt_uint8_t flag)
{
struct rt_timer *timer;
/* allocate a object */
timer = (struct rt_timer *)rt_object_allocate(RT_Object_Class_Timer, name);
if (timer == RT_NULL)
{
return RT_NULL;
}
_rt_timer_init(timer, timeout, parameter, time, flag);
return timer;
}
RTM_EXPORT(rt_timer_create);
/**
* This function will delete a timer and release timer memory
*
* @param timer the timer to be deleted
*
* @return the operation status, RT_EOK on OK; RT_ERROR on error
*/
rt_err_t rt_timer_delete(rt_timer_t timer)
{
register rt_base_t level;
/* timer check */
RT_ASSERT(timer != RT_NULL);
/* disable interrupt */
level = rt_hw_interrupt_disable();
_rt_timer_remove(timer);
/* enable interrupt */
rt_hw_interrupt_enable(level);
rt_object_delete((rt_object_t)timer);
return -RT_EOK;
}
RTM_EXPORT(rt_timer_delete);
#endif
/**
* This function will start the timer
*
* @param timer the timer to be started
*
* @return the operation status, RT_EOK on OK, -RT_ERROR on error
*/
rt_err_t rt_timer_start(rt_timer_t timer)
{
unsigned int row_lvl;
rt_list_t *timer_list;
register rt_base_t level;
rt_list_t *row_head[RT_TIMER_SKIP_LIST_LEVEL];
unsigned int tst_nr;
static unsigned int random_nr;
/* timer check */
RT_ASSERT(timer != RT_NULL);
/* stop timer firstly */
level = rt_hw_interrupt_disable();
/* remove timer from list */
_rt_timer_remove(timer);
/* change status of timer */
timer->parent.flag &= ~RT_TIMER_FLAG_ACTIVATED;
rt_hw_interrupt_enable(level);
RT_OBJECT_HOOK_CALL(rt_object_take_hook, (&(timer->parent)));
/*
* get timeout tick,
* the max timeout tick shall not great than RT_TICK_MAX/2
*/
RT_ASSERT(timer->init_tick < RT_TICK_MAX / 2);
timer->timeout_tick = rt_tick_get() + timer->init_tick;
/* disable interrupt */
level = rt_hw_interrupt_disable();
#ifdef RT_USING_TIMER_SOFT
if (timer->parent.flag & RT_TIMER_FLAG_SOFT_TIMER)
{
/* insert timer to soft timer list */
timer_list = rt_soft_timer_list;
}
else
#endif
{
/* insert timer to system timer list */
timer_list = rt_timer_list;
}
row_head[0] = &timer_list[0];
for (row_lvl = 0; row_lvl < RT_TIMER_SKIP_LIST_LEVEL; row_lvl++)
{
for (; row_head[row_lvl] != timer_list[row_lvl].prev;
row_head[row_lvl] = row_head[row_lvl]->next)
{
struct rt_timer *t;
rt_list_t *p = row_head[row_lvl]->next;
/* fix up the entry pointer */
t = rt_list_entry(p, struct rt_timer, row[row_lvl]);
/* If we have two timers that timeout at the same time, it's
* preferred that the timer inserted early get called early.
* So insert the new timer to the end the the some-timeout timer
* list.
*/
if ((t->timeout_tick - timer->timeout_tick) == 0)
{
continue;
}
else if ((t->timeout_tick - timer->timeout_tick) < RT_TICK_MAX / 2)
{
break;
}
}
if (row_lvl != RT_TIMER_SKIP_LIST_LEVEL - 1)
row_head[row_lvl + 1] = row_head[row_lvl] + 1;
}
/* Interestingly, this super simple timer insert counter works very very
* well on distributing the list height uniformly. By means of "very very
* well", I mean it beats the randomness of timer->timeout_tick very easily
* (actually, the timeout_tick is not random and easy to be attacked). */
random_nr++;
tst_nr = random_nr;
rt_list_insert_after(row_head[RT_TIMER_SKIP_LIST_LEVEL - 1],
&(timer->row[RT_TIMER_SKIP_LIST_LEVEL - 1]));
for (row_lvl = 2; row_lvl <= RT_TIMER_SKIP_LIST_LEVEL; row_lvl++)
{
if (!(tst_nr & RT_TIMER_SKIP_LIST_MASK))
rt_list_insert_after(row_head[RT_TIMER_SKIP_LIST_LEVEL - row_lvl],
&(timer->row[RT_TIMER_SKIP_LIST_LEVEL - row_lvl]));
else
break;
/* Shift over the bits we have tested. Works well with 1 bit and 2
* bits. */
tst_nr >>= (RT_TIMER_SKIP_LIST_MASK + 1) >> 1;
}
timer->parent.flag |= RT_TIMER_FLAG_ACTIVATED;
/* enable interrupt */
rt_hw_interrupt_enable(level);
#ifdef RT_USING_TIMER_SOFT
if (timer->parent.flag & RT_TIMER_FLAG_SOFT_TIMER)
{
/* check whether timer thread is ready */
if ((timer_thread.stat & RT_THREAD_STAT_MASK) != RT_THREAD_READY)
{
/* resume timer thread to check soft timer */
rt_thread_resume(&timer_thread);
rt_schedule();
}
}
#endif
return -RT_EOK;
}
RTM_EXPORT(rt_timer_start);
/**
* This function will stop the timer
*
* @param timer the timer to be stopped
*
* @return the operation status, RT_EOK on OK, -RT_ERROR on error
*/
rt_err_t rt_timer_stop(rt_timer_t timer)
{
register rt_base_t level;
/* timer check */
RT_ASSERT(timer != RT_NULL);
if (!(timer->parent.flag & RT_TIMER_FLAG_ACTIVATED))
return -RT_ERROR;
RT_OBJECT_HOOK_CALL(rt_object_put_hook, (&(timer->parent)));
/* disable interrupt */
level = rt_hw_interrupt_disable();
_rt_timer_remove(timer);
/* enable interrupt */
rt_hw_interrupt_enable(level);
/* change stat */
timer->parent.flag &= ~RT_TIMER_FLAG_ACTIVATED;
return RT_EOK;
}
RTM_EXPORT(rt_timer_stop);
/**
* This function will get or set some options of the timer
*
* @param timer the timer to be get or set
* @param cmd the control command
* @param arg the argument
*
* @return RT_EOK
*/
rt_err_t rt_timer_control(rt_timer_t timer, int cmd, void *arg)
{
/* timer check */
RT_ASSERT(timer != RT_NULL);
switch (cmd)
{
case RT_TIMER_CTRL_GET_TIME:
*(rt_tick_t *)arg = timer->init_tick;
break;
case RT_TIMER_CTRL_SET_TIME:
timer->init_tick = *(rt_tick_t *)arg;
break;
case RT_TIMER_CTRL_SET_ONESHOT:
timer->parent.flag &= ~RT_TIMER_FLAG_PERIODIC;
break;
case RT_TIMER_CTRL_SET_PERIODIC:
timer->parent.flag |= RT_TIMER_FLAG_PERIODIC;
break;
}
return RT_EOK;
}
RTM_EXPORT(rt_timer_control);
/**
* This function will check timer list, if a timeout event happens, the
* corresponding timeout function will be invoked.
*
* @note this function shall be invoked in operating system timer interrupt.
*/
void rt_timer_check(void)
{
struct rt_timer *t;
rt_tick_t current_tick;
register rt_base_t level;
RT_DEBUG_LOG(RT_DEBUG_TIMER, ("timer check enter\n"));
current_tick = rt_tick_get();
/* disable interrupt */
level = rt_hw_interrupt_disable();
while (!rt_list_isempty(&rt_timer_list[RT_TIMER_SKIP_LIST_LEVEL - 1]))
{
t = rt_list_entry(rt_timer_list[RT_TIMER_SKIP_LIST_LEVEL - 1].next,
struct rt_timer, row[RT_TIMER_SKIP_LIST_LEVEL - 1]);
/*
* It supposes that the new tick shall less than the half duration of
* tick max.
*/
if ((current_tick - t->timeout_tick) < RT_TICK_MAX / 2)
{
RT_OBJECT_HOOK_CALL(rt_timer_timeout_hook, (t));
/* remove timer from timer list firstly */
_rt_timer_remove(t);
/* call timeout function */
t->timeout_func(t->parameter);
/* re-get tick */
current_tick = rt_tick_get();
RT_DEBUG_LOG(RT_DEBUG_TIMER, ("current tick: %d\n", current_tick));
if ((t->parent.flag & RT_TIMER_FLAG_PERIODIC) &&
(t->parent.flag & RT_TIMER_FLAG_ACTIVATED))
{
/* start it */
t->parent.flag &= ~RT_TIMER_FLAG_ACTIVATED;
rt_timer_start(t);
}
else
{
/* stop timer */
t->parent.flag &= ~RT_TIMER_FLAG_ACTIVATED;
}
}
else
break;
}
/* enable interrupt */
rt_hw_interrupt_enable(level);
RT_DEBUG_LOG(RT_DEBUG_TIMER, ("timer check leave\n"));
}
/**
* This function will return the next timeout tick in the system.
*
* @return the next timeout tick in the system
*/
rt_tick_t rt_timer_next_timeout_tick(void)
{
return rt_timer_list_next_timeout(rt_timer_list);
}
#ifdef RT_USING_TIMER_SOFT
/**
* This function will check timer list, if a timeout event happens, the
* corresponding timeout function will be invoked.
*/
void rt_soft_timer_check(void)
{
rt_tick_t current_tick;
rt_list_t *n;
struct rt_timer *t;
RT_DEBUG_LOG(RT_DEBUG_TIMER, ("software timer check enter\n"));
current_tick = rt_tick_get();
/* lock scheduler */
rt_enter_critical();
for (n = rt_soft_timer_list[RT_TIMER_SKIP_LIST_LEVEL - 1].next;
n != &(rt_soft_timer_list[RT_TIMER_SKIP_LIST_LEVEL - 1]);)
{
t = rt_list_entry(n, struct rt_timer, row[RT_TIMER_SKIP_LIST_LEVEL - 1]);
/*
* It supposes that the new tick shall less than the half duration of
* tick max.
*/
if ((current_tick - t->timeout_tick) < RT_TICK_MAX / 2)
{
RT_OBJECT_HOOK_CALL(rt_timer_timeout_hook, (t));
/* move node to the next */
n = n->next;
/* remove timer from timer list firstly */
_rt_timer_remove(t);
/* not lock scheduler when performing timeout function */
rt_exit_critical();
/* call timeout function */
t->timeout_func(t->parameter);
/* re-get tick */
current_tick = rt_tick_get();
RT_DEBUG_LOG(RT_DEBUG_TIMER, ("current tick: %d\n", current_tick));
/* lock scheduler */
rt_enter_critical();
if ((t->parent.flag & RT_TIMER_FLAG_PERIODIC) &&
(t->parent.flag & RT_TIMER_FLAG_ACTIVATED))
{
/* start it */
t->parent.flag &= ~RT_TIMER_FLAG_ACTIVATED;
rt_timer_start(t);
}
else
{
/* stop timer */
t->parent.flag &= ~RT_TIMER_FLAG_ACTIVATED;
}
}
else break; /* not check anymore */
}
/* unlock scheduler */
rt_exit_critical();
RT_DEBUG_LOG(RT_DEBUG_TIMER, ("software timer check leave\n"));
}
/* system timer thread entry */
static void rt_thread_timer_entry(void *parameter)
{
rt_tick_t next_timeout;
while (1)
{
/* get the next timeout tick */
next_timeout = rt_timer_list_next_timeout(rt_soft_timer_list);
if (next_timeout == RT_TICK_MAX)
{
/* no software timer exist, suspend self. */
rt_thread_suspend(rt_thread_self());
rt_schedule();
}
else
{
rt_tick_t current_tick;
/* get current tick */
current_tick = rt_tick_get();
if ((next_timeout - current_tick) < RT_TICK_MAX / 2)
{
/* get the delta timeout tick */
next_timeout = next_timeout - current_tick;
rt_thread_delay(next_timeout);
}
}
/* check software timer */
rt_soft_timer_check();
}
}
#endif
/**
* @ingroup SystemInit
*
* This function will initialize system timer
*/
void rt_system_timer_init(void)
{
int i;
for (i = 0; i < sizeof(rt_timer_list) / sizeof(rt_timer_list[0]); i++)
{
rt_list_init(rt_timer_list + i);
}
}
/**
* @ingroup SystemInit
*
* This function will initialize system timer thread
*/
void rt_system_timer_thread_init(void)
{
#ifdef RT_USING_TIMER_SOFT
int i;
for (i = 0;
i < sizeof(rt_soft_timer_list) / sizeof(rt_soft_timer_list[0]);
i++)
{
rt_list_init(rt_soft_timer_list + i);
}
/* start software timer thread */
rt_thread_init(&timer_thread,
"timer",
rt_thread_timer_entry,
RT_NULL,
&timer_thread_stack[0],
sizeof(timer_thread_stack),
RT_TIMER_THREAD_PRIO,
10);
/* startup */
rt_thread_startup(&timer_thread);
#endif
}
/**@}*/