+++ /dev/null
-/*
- * Copyright Droids Corporation, Microb Technology, Eirbot (2005)
- *
- * 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., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
- *
- * Revision : $Id: scheduler_interrupt.c,v 1.1.2.9 2009-11-08 17:33:14 zer0 Exp $
- *
- */
-
-#include <stdlib.h>
-
-#include <aversive.h>
-#include <scheduler_config.h>
-#include <scheduler_private.h>
-#include <scheduler_stats.h>
-
-/** priority of the running event */
-static volatile uint8_t priority_running=0;
-
-/** number of imbricated scheduler interruptions */
-static volatile uint8_t nb_stacking=0;
-
-uint8_t scheduler_disable_save(void)
-{
- uint8_t ret;
- ret = priority_running;
- priority_running = 255;
- return ret;
-}
-
-void scheduler_enable_restore(uint8_t old_prio)
-{
- priority_running = old_prio;
-}
-
-/**
- * this function is called from a timer interruption. If an event has
- * to be scheduled, it will execute the fonction (IRQ are allowed
- * during the execution of the function). This interruption can be
- * interrupted by itself too, in this case only events with a higher
- * priority can be scheduled.
- *
- * We assume that this function is called from a SIGNAL(), with
- * global interrupt flag disabled --> that's why we can use cli() and
- * sei() instead of IRQ_LOCK(flags).
- */
-void
-scheduler_interrupt(void)
-{
- uint8_t i;
- uint8_t priority_tmp;
- SLIST_HEAD(event_list_t, event_t) event_list;
- struct event_t *e, *next_e, *prev_e=NULL;
-
- /* maximize the number of imbrications */
- if (nb_stacking >= SCHEDULER_NB_STACKING_MAX) {
- SCHED_INC_STAT(max_stacking);
- return;
- }
-
- nb_stacking ++;
- sei();
-
- SLIST_INIT(&event_list);
-
- /* browse events table to determine which events should be
- * scheduled */
- for (i=0 ; i<SCHEDULER_NB_MAX_EVENT ; i++) {
- cli();
-
- /* the event is already present in a schedule list,
- * only update its current time until it reaches 1 */
- if (g_tab_event[i].state == SCHEDULER_EVENT_SCHEDULED) {
- if (g_tab_event[i].current_time > 1) {
- g_tab_event[i].current_time --;
- sei();
- continue;
- }
- else {
- SCHED_INC_STAT2(task_delayed, i);
- sei();
- continue;
- }
- }
-
- /* nothing to do with other unactive events */
- if (g_tab_event[i].state != SCHEDULER_EVENT_ACTIVE) {
- sei();
- continue;
- }
-
- /* decrement current time (we know it is >0 if it is
- * in SCHEDULER_EVENT_ACTIVE state */
- g_tab_event[i].current_time --;
-
- /* don't need to schedule now */
- if ( g_tab_event[i].current_time != 0 ) {
- sei();
- continue;
- }
-
- /* time to schedule, but priority is too low,
- * delay it */
- if (g_tab_event[i].priority <= priority_running) {
- g_tab_event[i].current_time = 1;
- SCHED_INC_STAT2(task_delayed, i);
- sei();
- continue;
- }
-
- /* reload event (it is 0 if it is non-periodical) */
- g_tab_event[i].current_time = g_tab_event[i].period;
-
- /* schedule it */
- g_tab_event[i].state = SCHEDULER_EVENT_SCHEDULED;
- SCHED_INC_STAT2(task_scheduled, i);
- sei();
-
- /* insert it in the list (list is ordered).
- this should be quite fast since the list is
- expected to be small. */
-
- e = SLIST_FIRST(&event_list);
- /* easy case : list is empty */
- if (e == NULL) {
- SLIST_INSERT_HEAD(&event_list, &g_tab_event[i], next);
- continue;
- }
-
- /* insert at head if it's the event with highest prio */
- if (g_tab_event[i].priority >= e->priority) {
- SLIST_INSERT_HEAD(&event_list, &g_tab_event[i], next);
- continue;
- }
-
- /* harder : find the good place in list */
- SLIST_FOREACH(e, &event_list, next) {
- next_e = SLIST_NEXT(e, next);
- if (next_e == NULL ||
- g_tab_event[i].priority >= next_e->priority) {
- SLIST_INSERT_AFTER(e, &g_tab_event[i], next);
- break;
- }
- }
- }
-
- /* only called if SCHEDULER_DEBUG is defined */
- DUMP_EVENTS();
-
- cli();
- priority_tmp = priority_running;
-
- SLIST_FOREACH(e, &event_list, next) {
- /* remove previous elt from list */
- if (prev_e)
- SLIST_NEXT(prev_e, next) = NULL;
-
- /* set running priority */
- priority_running = e->priority;
- sei();
-
- /* the following fields (f and data) can't be modified
- * while an event is in state SCHEDULED */
- e->f(e->data);
-
- cli();
- /* free it if it is single (non-periodical) */
- if (!e->period) {
- e->state = SCHEDULER_EVENT_FREE;
- }
-
- /* free event if someone asked for deletion during
- * schedule */
- if (e->state == SCHEDULER_EVENT_DELETING) {
- e->state = SCHEDULER_EVENT_FREE;
- }
-
- /* end of schedule, mark it as active */
- if (e->state == SCHEDULER_EVENT_SCHEDULED) {
- e->state = SCHEDULER_EVENT_ACTIVE;
- }
-
- prev_e = e;
- }
- /* remove previous elt from list */
- if (prev_e)
- SLIST_NEXT(prev_e, next) = NULL;
-
- priority_running = priority_tmp;
- nb_stacking--;
-}
git.droids-corp.org / protos / xbee-avr.git / blobdiff