nodemcu-firmware/components/task/task.c

145 lines
3.8 KiB
C

/**
This file encapsulates the SDK-based task handling for the NodeMCU Lua firmware.
*/
#include "task/task.h"
#include <stdlib.h>
#include <string.h>
#include "freertos/FreeRTOS.h"
#include "freertos/queue.h"
#include "freertos/semphr.h"
#define TASK_HANDLE_MONIKER 0x68680000
#define TASK_HANDLE_MASK 0xFFF80000
#define TASK_HANDLE_UNMASK (~TASK_HANDLE_MASK)
#define TASK_HANDLE_ALLOCATION_BRICK 4 // must be a power of 2
#define TASK_DEFAULT_QUEUE_LEN 8
#define CHECK(p,v,msg) if (!(p)) { NODE_DBG ( msg ); return (v); }
#ifndef NODE_DBG
# define NODE_DBG(...) do{}while(0)
#endif
typedef struct
{
task_handle_t sig;
task_param_t par;
} task_event_t;
/*
* Private arrays to hold the 3 event task queues and the dispatch callbacks
*/
static xQueueHandle task_Q[TASK_PRIORITY_COUNT];
/* Rather than using a QueueSet (which requires queues to be empty when created)
* we use a binary semaphore to unblock the pump whenever something is posted */
static xSemaphoreHandle pending;
static task_callback_t *task_func;
static int task_count;
/*
* Initialise the task handle callback for a given priority. This doesn't need
* to be called explicitly as the get_id function will call this lazily.
*/
bool task_init_handler(task_prio_t priority, uint8 qlen) {
if (priority >= TASK_PRIORITY_COUNT)
return false;
if (task_Q[priority] == NULL)
{
task_Q[priority] = xQueueCreate (qlen, sizeof (task_event_t));
return task_Q[priority] != NULL;
}
else
return false;
}
task_handle_t task_get_id(task_callback_t t) {
/* Initialise any uninitialised Qs with the default Q len */
for (task_prio_t p = TASK_PRIORITY_LOW; p != TASK_PRIORITY_COUNT; ++p)
{
if (!task_Q[p]) {
CHECK(task_init_handler( p, TASK_DEFAULT_QUEUE_LEN ), 0, "Task initialisation failed");
}
}
if ( (task_count & (TASK_HANDLE_ALLOCATION_BRICK - 1)) == 0 ) {
/* With a brick size of 4 this branch is taken at 0, 4, 8 ... and the new size is +4 */
task_func =(task_callback_t *)realloc(
task_func,
sizeof(task_callback_t)*(task_count+TASK_HANDLE_ALLOCATION_BRICK));
CHECK(task_func, 0 , "Malloc failure in task_get_id");
memset (task_func+task_count, 0, sizeof(task_callback_t)*TASK_HANDLE_ALLOCATION_BRICK);
}
task_func[task_count] = t;
return TASK_HANDLE_MONIKER | task_count++;
}
bool task_post (task_prio_t priority, task_handle_t handle, task_param_t param)
{
if (priority >= TASK_PRIORITY_COUNT ||
!task_Q[priority] ||
(handle & TASK_HANDLE_MASK) != TASK_HANDLE_MONIKER)
return false;
task_event_t ev = { handle, param };
bool res = pdPASS == xQueueSendToBackFromISR (task_Q[priority], &ev, NULL);
if (pending) /* only need to raise semaphore if it's been initialised */
xSemaphoreGiveFromISR (pending, NULL);
return res;
}
static bool next_event (task_event_t *ev, task_prio_t *prio)
{
for (task_prio_t pr = TASK_PRIORITY_COUNT; pr != TASK_PRIORITY_LOW; --pr)
{
task_prio_t p = pr -1;
if (task_Q[p] && xQueueReceive (task_Q[p], ev, 0) == pdTRUE)
{
*prio = p;
return true;
}
}
return false; // no events queued
}
static void dispatch (task_event_t *e, uint8_t prio) {
task_handle_t handle = e->sig;
if ( (handle & TASK_HANDLE_MASK) == TASK_HANDLE_MONIKER) {
uint16_t entry = (handle & TASK_HANDLE_UNMASK);
if ( task_func && entry < task_count ){
/* call the registered task handler with the specified parameter and priority */
task_func[entry](e->par, prio);
return;
}
}
/* Invalid signals are ignored */
NODE_DBG ( "Invalid signal issued: %08x", handle);
}
void task_pump_messages (void)
{
vSemaphoreCreateBinary (pending);
for (;;)
{
task_event_t ev;
task_prio_t prio;
if (next_event (&ev, &prio))
dispatch (&ev, prio);
else
xSemaphoreTake (pending, portMAX_DELAY);
}
}