/**
* @file lv_task.c
* An 'lv_task' is a void (*fp) (void* param) type function which will be called periodically.
* A priority (5 levels + disable) can be assigned to lv_tasks.
*/
/*********************
* INCLUDES
*********************/
#include <stddef.h>
#include "lv_task.h"
#include "../lv_hal/lv_hal_tick.h"
#include "lv_gc.h"
#if defined(LV_GC_INCLUDE)
#include LV_GC_INCLUDE
#endif /* LV_ENABLE_GC */
/*********************
* DEFINES
*********************/
#define IDLE_MEAS_PERIOD 500 /*[ms]*/
#define DEF_PRIO LV_TASK_PRIO_MID
#define DEF_PERIOD 500
/**********************
* TYPEDEFS
**********************/
/**********************
* STATIC PROTOTYPES
**********************/
static bool lv_task_exec(lv_task_t * task);
/**********************
* STATIC VARIABLES
**********************/
static bool lv_task_run = false;
static uint8_t idle_last = 0;
static bool task_deleted;
static bool task_created;
/**********************
* MACROS
**********************/
/**********************
* GLOBAL FUNCTIONS
**********************/
/**
* Init the lv_task module
*/
void lv_task_core_init(void)
{
lv_ll_init(&LV_GC_ROOT(_lv_task_ll), sizeof(lv_task_t));
/*Initially enable the lv_task handling*/
lv_task_enable(true);
}
/**
* Call it periodically to handle lv_tasks.
*/
LV_ATTRIBUTE_TASK_HANDLER void lv_task_handler(void)
{
LV_LOG_TRACE("lv_task_handler started");
/*Avoid concurrent running of the task handler*/
static bool task_handler_mutex = false;
if(task_handler_mutex) return;
task_handler_mutex = true;
static uint32_t idle_period_start = 0;
static uint32_t handler_start = 0;
static uint32_t busy_time = 0;
if(lv_task_run == false) {
task_handler_mutex = false; /*Release mutex*/
return;
}
handler_start = lv_tick_get();
/* Run all task from the highest to the lowest priority
* If a lower priority task is executed check task again from the highest priority
* but on the priority of executed tasks don't run tasks before the executed*/
lv_task_t * task_interrupter = NULL;
lv_task_t * next;
bool end_flag;
do {
end_flag = true;
task_deleted = false;
task_created = false;
LV_GC_ROOT(_lv_task_act) = lv_ll_get_head(&LV_GC_ROOT(_lv_task_ll));
while(LV_GC_ROOT(_lv_task_act)) {
/* The task might be deleted if it runs only once ('once = 1')
* So get next element until the current is surely valid*/
next = lv_ll_get_next(&LV_GC_ROOT(_lv_task_ll), LV_GC_ROOT(_lv_task_act));
/*We reach priority of the turned off task. There is nothing more to do.*/
if(((lv_task_t *)LV_GC_ROOT(_lv_task_act))->prio == LV_TASK_PRIO_OFF) {
break;
}
/*Here is the interrupter task. Don't execute it again.*/
if(LV_GC_ROOT(_lv_task_act) == task_interrupter) {
task_interrupter = NULL; /*From this point only task after the interrupter comes, so
the interrupter is not interesting anymore*/
LV_GC_ROOT(_lv_task_act) = next;
continue; /*Load the next task*/
}
/*Just try to run the tasks with highest priority.*/
if(((lv_task_t *)LV_GC_ROOT(_lv_task_act))->prio == LV_TASK_PRIO_HIGHEST) {
lv_task_exec(LV_GC_ROOT(_lv_task_act));
}
/*Tasks with higher priority then the interrupted shall be run in every case*/
else if(task_interrupter) {
if(((lv_task_t *)LV_GC_ROOT(_lv_task_act))->prio > task_interrupter->prio) {
if(lv_task_exec(LV_GC_ROOT(_lv_task_act))) {
task_interrupter =
LV_GC_ROOT(_lv_task_act); /*Check all tasks again from the highest priority */
end_flag = false;
break;
}
}
}
/* It is no interrupter task or we already reached it earlier.
* Just run the remaining tasks*/
else {
if(lv_task_exec(LV_GC_ROOT(_lv_task_act))) {
task_interrupter = LV_GC_ROOT(_lv_task_act); /*Check all tasks again from the highest priority */
end_flag = false;
break;
}
}
if(task_deleted) break; /*If a task was deleted then this or the next item might be corrupted*/
if(task_created) break; /*If a task was created then this or the next item might be corrupted*/
LV_GC_ROOT(_lv_task_act) = next; /*Load the next task*/
}
} while(!end_flag);
busy_time += lv_tick_elaps(handler_start);
uint32_t idle_period_time = lv_tick_elaps(idle_period_start);
if(idle_period_time >= IDLE_MEAS_PERIOD) {
idle_last = (uint32_t)((uint32_t)busy_time * 100) / IDLE_MEAS_PERIOD; /*Calculate the busy percentage*/
idle_last = idle_last > 100 ? 0 : 100 - idle_last; /*But we need idle time*/
busy_time = 0;
idle_period_start = lv_tick_get();
}
task_handler_mutex = false; /*Release the mutex*/
LV_LOG_TRACE("lv_task_handler ready");
}
/**
* Create an "empty" task. It needs to initialzed with at least
* `lv_task_set_cb` and `lv_task_set_period`
* @return pointer to the craeted task
*/
lv_task_t * lv_task_create_basic(void)
{
lv_task_t * new_task = NULL;
lv_task_t * tmp;
/*Create task lists in order of priority from high to low*/
tmp = lv_ll_get_head(&LV_GC_ROOT(_lv_task_ll));
/*It's the first task*/
if(NULL == tmp) {
new_task = lv_ll_ins_head(&LV_GC_ROOT(_lv_task_ll));
lv_mem_assert(new_task);
if(new_task == NULL) return NULL;
}
/*Insert the new task to proper place according to its priority*/
else {
do {
if(tmp->prio <= DEF_PRIO) {
new_task = lv_ll_ins_prev(&LV_GC_ROOT(_lv_task_ll), tmp);
lv_mem_assert(new_task);
if(new_task == NULL) return NULL;
break;
}
tmp = lv_ll_get_next(&LV_GC_ROOT(_lv_task_ll), tmp);
} while(tmp != NULL);
/*Only too high priority tasks were found. Add the task to the end*/
if(tmp == NULL) {
new_task = lv_ll_ins_tail(&LV_GC_ROOT(_lv_task_ll));
lv_mem_assert(new_task);
if(new_task == NULL) return NULL;
}
}
new_task->period = DEF_PERIOD;
new_task->task_cb = NULL;
new_task->prio = DEF_PRIO;
new_task->once = 0;
new_task->last_run = lv_tick_get();
new_task->user_data = NULL;
task_created = true;
return new_task;
}
/**
* Create a new lv_task
* @param task_xcb a callback which is the task itself. It will be called periodically.
* (the 'x' in the argument name indicates that its not a fully generic function because it not follows
* the `func_name(object, callback, ...)` convention)
* @param period call period in ms unit
* @param prio priority of the task (LV_TASK_PRIO_OFF means the task is stopped)
* @param user_data custom parameter
* @return pointer to the new task
*/
lv_task_t * lv_task_create(lv_task_cb_t task_cb, uint32_t period, lv_task_prio_t prio, void * user_data)
{
lv_task_t * new_task = lv_task_create_basic();
lv_mem_assert(new_task);
if(new_task == NULL) return NULL;
lv_task_set_cb(new_task, task_cb);
lv_task_set_period(new_task, period);
lv_task_set_prio(new_task, prio);
new_task->user_data = user_data;
return new_task;
}
/**
* Set the callback the task (the function to call periodically)
* @param task pointer to a task
* @param task_cb teh function to call periodically
*/
void lv_task_set_cb(lv_task_t * task, lv_task_cb_t task_cb)
{
task->task_cb = task_cb;
}
/**
* Delete a lv_task
* @param task pointer to task created by task
*/
void lv_task_del(lv_task_t * task)
{
lv_ll_rem(&LV_GC_ROOT(_lv_task_ll), task);
lv_mem_free(task);
if(LV_GC_ROOT(_lv_task_act) == task) task_deleted = true; /*The active task was deleted*/
}
/**
* Set new priority for a lv_task
* @param task pointer to a lv_task
* @param prio the new priority
*/
void lv_task_set_prio(lv_task_t * task, lv_task_prio_t prio)
{
if(task->prio == prio) return;
/*Find the tasks with new priority*/
lv_task_t * i;
LV_LL_READ(LV_GC_ROOT(_lv_task_ll), i)
{
if(i->prio <= prio) {
if(i != task) lv_ll_move_before(&LV_GC_ROOT(_lv_task_ll), task, i);
break;
}
}
/*There was no such a low priority so far then add the node to the tail*/
if(i == NULL) {
lv_ll_move_before(&LV_GC_ROOT(_lv_task_ll), task, NULL);
}
task->prio = prio;
}
/**
* Set new period for a lv_task
* @param task pointer to a lv_task
* @param period the new period
*/
void lv_task_set_period(lv_task_t * task, uint32_t period)
{
task->period = period;
}
/**
* Make a lv_task ready. It will not wait its period.
* @param task pointer to a lv_task.
*/
void lv_task_ready(lv_task_t * task)
{
task->last_run = lv_tick_get() - task->period - 1;
}
/**
* Delete the lv_task after one call
* @param task pointer to a lv_task.
*/
void lv_task_once(lv_task_t * task)
{
task->once = 1;
}
/**
* Reset a lv_task.
* It will be called the previously set period milliseconds later.
* @param task pointer to a lv_task.
*/
void lv_task_reset(lv_task_t * task)
{
task->last_run = lv_tick_get();
}
/**
* Enable or disable the whole lv_task handling
* @param en: true: lv_task handling is running, false: lv_task handling is suspended
*/
void lv_task_enable(bool en)
{
lv_task_run = en;
}
/**
* Get idle percentage
* @return the lv_task idle in percentage
*/
uint8_t lv_task_get_idle(void)
{
return idle_last;
}
/**********************
* STATIC FUNCTIONS
**********************/
/**
* Execute task if its the priority is appropriate
* @param task pointer to lv_task
* @return true: execute, false: not executed
*/
static bool lv_task_exec(lv_task_t * task)
{
bool exec = false;
/*Execute if at least 'period' time elapsed*/
uint32_t elp = lv_tick_elaps(task->last_run);
if(elp >= task->period) {
task->last_run = lv_tick_get();
task_deleted = false;
task_created = false;
if(task->task_cb) task->task_cb(task);
/*Delete if it was a one shot lv_task*/
if(task_deleted == false) { /*The task might be deleted by itself as well*/
if(task->once != 0) {
lv_task_del(task);
}
}
exec = true;
}
return exec;
}