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/*
* Project: S.Ha.R.K.
*
* Coordinators:
* Giorgio Buttazzo <giorgio@sssup.it>
* Paolo Gai <pj@gandalf.sssup.it>
*
* Authors :
* Paolo Gai <pj@gandalf.sssup.it>
* Massimiliano Giorgi <massy@gandalf.sssup.it>
* Luca Abeni <luca@gandalf.sssup.it>
* (see the web pages for full authors list)
*
* ReTiS Lab (Scuola Superiore S.Anna - Pisa - Italy)
*
* http://www.sssup.it
* http://retis.sssup.it
* http://shark.sssup.it
*/
/**
------------
CVS : $Id: rrsoft.c,v 1.6 2003-12-10 16:55:01 giacomo Exp $
File: $File$
Revision: $Revision: 1.6 $
Last update: $Date: 2003-12-10 16:55:01 $
------------
This file contains the scheduling module RRSOFT (Round Robin)
Read rrsoft.h for further details.
**/
/*
* Copyright (C) 2000 Paolo Gai
*
* 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 WARRSOFTANTY; without even the implied waRRSOFTanty 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
*
*/
#include <modules/rrsoft.h>
#include <ll/stdio.h>
#include <ll/string.h>
#include <kernel/model.h>
#include <kernel/descr.h>
#include <kernel/var.h>
#include <kernel/func.h>
#include <tracer.h>
/*+ Status used in the level +*/
#define RRSOFT_READY MODULE_STATUS_BASE
#define RRSOFT_IDLE MODULE_STATUS_BASE+2
/*+ the level redefinition for the Round Robin level +*/
typedef struct {
level_des l; /*+ the standard level descriptor +*/
int nact[MAX_PROC]; /*+ number of pending activations +*/
IQUEUE ready; /*+ the ready queue +*/
int slice; /*+ the level's time slice +*/
TIME period[MAX_PROC]; /*+ activation period +*/
struct timespec reactivation_time[MAX_PROC];
/*+ the time at witch the reactivation timer is post +*/
int reactivation_timer[MAX_PROC];
/*+ the recativation timer +*/
BYTE periodic[MAX_PROC];
struct multiboot_info *multiboot; /*+ used if the level have to insert
the main task +*/
BYTE models; /*+ Task Model that the Module can Handle +*/
} RRSOFT_level_des;
/* this is the periodic reactivation of the task... it is posted only
if the task is a periodic task */
static void RRSOFT_timer_reactivate(void *par)
{
PID p = (PID) par;
RRSOFT_level_des *lev;
// kern_printf("react");
lev = (RRSOFT_level_des *)level_table[proc_table[p].task_level];
if (proc_table[p].status == RRSOFT_IDLE) {
/* the task has finished the current activation and must be
reactivated */
proc_table[p].status = RRSOFT_READY;
iq_insertlast(p,&lev->ready);
event_need_reschedule();
}
else if (lev->nact[p] >= 0)
/* the task has not completed the current activation, so we save
the activation incrementing nact... */
lev->nact[p]++;
/* repost the event at the next period end... */
ADDUSEC2TIMESPEC(lev->period[p], &lev->reactivation_time[p]);
lev->reactivation_timer[p] = kern_event_post(&lev->reactivation_time[p],
RRSOFT_timer_reactivate,
(void *)p);
}
/* This is not efficient but very fair :-)
The need of all this stuff is because if a task execute a long time
due to (shadow!) priority inheritance, then the task shall go to the
tail of the queue many times... */
static PID RRSOFT_public_scheduler(LEVEL l)
{
RRSOFT_level_des *lev = (RRSOFT_level_des *)(level_table[l]);
PID p;
for (;;) {
p = iq_query_first(&lev->ready);
if (p == -1)
return p;
//{kern_printf("(s%d)",p); return p;}
// kern_printf("(p=%d l=%d avail=%d wcet =%d)\n",p,l,proc_table[p].avail_time, proc_table[p].wcet);
if (proc_table[p].avail_time <= 0) {
proc_table[p].avail_time += proc_table[p].wcet;
iq_extract(p,&lev->ready);
iq_insertlast(p,&lev->ready);
}
else
//{kern_printf("(s%d)",p); return p;}
return p;
}
}
static int RRSOFT_public_create(LEVEL l, PID p, TASK_MODEL *m)
{
RRSOFT_level_des *lev = (RRSOFT_level_des *)(level_table[l]);
// kern_printf("create %d mod %d\n",p,m->pclass);
/* the task state is set at SLEEP by the general task_create
the only thing to set remains the capacity stuffs that are set
to the values passed in the model... */
if (m->pclass==NRT_PCLASS && !(lev->models & RRSOFT_ONLY_NRT) ) return -1;
if (m->pclass==SOFT_PCLASS && !(lev->models & RRSOFT_ONLY_SOFT) ) return -1;
if (m->pclass==HARD_PCLASS && !(lev->models & RRSOFT_ONLY_HARD) ) return -1;
if (m->level != 0 && m->level != l) return -1;
/* I used the wcet field because using wcet can account if a task
consume more than the timeslice... */
if (lev->models & RRSOFT_ONLY_NRT &&
(m->pclass == NRT_PCLASS || m->pclass == (NRT_PCLASS | l))) {
NRT_TASK_MODEL *nrt = (NRT_TASK_MODEL *)m;
// kern_printf("nrt");
if (nrt->slice) {
proc_table[p].avail_time = nrt->slice;
proc_table[p].wcet = nrt->slice;
}
else {
proc_table[p].avail_time = lev->slice;
proc_table[p].wcet = lev->slice;
}
proc_table[p].control |= CONTROL_CAP;
if (nrt->arrivals == SAVE_ARRIVALS)
lev->nact[p] = 0;
else
lev->nact[p] = -1;
lev->periodic[p] = 0;
lev->period[p] = 0;
}
else if (lev->models & RRSOFT_ONLY_SOFT &&
(m->pclass == SOFT_PCLASS || m->pclass == (SOFT_PCLASS | l))) {
SOFT_TASK_MODEL *soft = (SOFT_TASK_MODEL *)m;
// kern_printf("soft");
proc_table[p].avail_time = lev->slice;
proc_table[p].wcet = lev->slice;
proc_table[p].control |= CONTROL_CAP;
if (soft->arrivals == SAVE_ARRIVALS)
lev->nact[p] = 0;
else
lev->nact[p] = -1;
if (soft->periodicity == PERIODIC) {
lev->periodic[p] = 1;
lev->period[p] = soft->period;
}
}
else if (lev->models & RRSOFT_ONLY_HARD &&
(m->pclass == HARD_PCLASS || m->pclass == (HARD_PCLASS | l))) {
HARD_TASK_MODEL *hard = (HARD_TASK_MODEL *)m;
// kern_printf("hard");
proc_table[p].avail_time = lev->slice;
proc_table[p].wcet = lev->slice;
proc_table[p].control |= CONTROL_CAP;
lev->nact[p] = 0;
if (hard->periodicity == PERIODIC) {
lev->periodic[p] = 1;
lev->period[p] = hard->mit;
}
}
return 0; /* OK */
}
static void RRSOFT_public_dispatch(LEVEL l, PID p, int nostop)
{
RRSOFT_level_des *lev = (RRSOFT_level_des *)(level_table[l]);
/* the task state is set EXE by the scheduler()
we extract the task from the ready queue
NB: we can't assume that p is the first task in the queue!!! */
iq_extract(p, &lev->ready);
}
static void RRSOFT_public_epilogue(LEVEL l, PID p)
{
RRSOFT_level_des *lev = (RRSOFT_level_des *)(level_table[l]);
/* check if the slice is finished and insert the task in the coRRSOFTect
qqueue position */
if (proc_table[p].avail_time <= 0) {
proc_table[p].avail_time += proc_table[p].wcet;
iq_insertlast(p,&lev->ready);
}
else
/* curr is >0, so the running task have to run for another cuRRSOFT usec */
iq_insertfirst(p,&lev->ready);
proc_table[p].status = RRSOFT_READY;
}
static void RRSOFT_public_activate(LEVEL l, PID p)
{
RRSOFT_level_des *lev = (RRSOFT_level_des *)(level_table[l]);
/* Test if we are trying to activate a non sleeping task */
/* save activation (only if needed... */
if (proc_table[p].status != SLEEP && proc_table[p].status != RRSOFT_IDLE) {
if (lev->nact[p] != -1)
lev->nact[p]++;
return;
}
/* Insert task in the correct position */
proc_table[p].status = RRSOFT_READY;
iq_insertlast(p,&lev->ready);
/* Set the reactivation timer */
if (lev->periodic[p])
{
kern_gettime(&lev->reactivation_time[p]);
ADDUSEC2TIMESPEC(lev->period[p], &lev->reactivation_time[p]);
lev->reactivation_timer[p] = kern_event_post(&lev->reactivation_time[p],
RRSOFT_timer_reactivate,
(void *)p);
}
}
static void RRSOFT_public_unblock(LEVEL l, PID p)
{
RRSOFT_level_des *lev = (RRSOFT_level_des *)(level_table[l]);
/* Similar to RRSOFT_task_activate, but we don't check in what state
the task is */
/* Insert task in the coRRSOFTect position */
proc_table[p].status = RRSOFT_READY;
iq_insertlast(p,&lev->ready);
}
static void RRSOFT_public_block(LEVEL l, PID p)
{
/* Extract the running task from the level
. we have already extract it from the ready queue at the dispatch time.
. the capacity event have to be removed by the generic kernel
. the wcet don't need modification...
. the state of the task is set by the calling function
So, we do nothing!!!
*/
}
static int RRSOFT_public_message(LEVEL l, PID p, void *m)
{
RRSOFT_level_des *lev = (RRSOFT_level_des *)(level_table[l]);
if (lev->nact[p] > 0) {
/* continue!!!! */
lev->nact[p]--;
// qq_insertlast(p,&lev->ready);
iq_insertfirst(p,&lev->ready);
proc_table[p].status = RRSOFT_READY;
}
else
proc_table[p].status = RRSOFT_IDLE;
jet_update_endcycle(); /* Update the Jet data... */
TRACER_LOGEVENT(FTrace_EVT_task_end_cycle,3,p,l);
return 0;
}
static void RRSOFT_public_end(LEVEL l, PID p)
{
RRSOFT_level_des *lev = (RRSOFT_level_des *)(level_table[l]);
lev->nact[p] = -1;
/* we delete the reactivation timer */
if (lev->periodic[p]) {
kern_event_delete(lev->reactivation_timer[p]);
lev->reactivation_timer[p] = -1;
}
/* then, we insert the task in the free queue */
proc_table[p].status = FREE;
iq_insertlast(p,&freedesc);
}
/* Registration functions */
/*+ This init function install the "main" task +*/
static void RRSOFT_call_main(void *l)
{
LEVEL lev;
PID p;
NRT_TASK_MODEL m;
void *mb;
lev = (LEVEL)l;
nrt_task_default_model(m);
nrt_task_def_level(m,lev); /* with this we are sure that the task aRRSOFTives
to the coRRSOFTect level */
mb = ((RRSOFT_level_des *)level_table[lev])->multiboot;
nrt_task_def_arg(m,mb);
nrt_task_def_usemath(m);
nrt_task_def_nokill(m);
nrt_task_def_ctrl_jet(m);
p = task_create("Main", __init__, (TASK_MODEL *)&m, NULL);
if (p == NIL)
printk("\nPanic!!! can't create main task...\n");
RRSOFT_public_activate(lev,p);
}
/*+ Registration function:
TIME slice the slice for the Round Robin queue
int createmain 1 if the level creates the main task 0 otherwise
struct multiboot_info *mb used if createmain specified +*/
LEVEL RRSOFT_register_level(TIME slice,
int createmain,
struct multiboot_info *mb,
BYTE models)
{
LEVEL l; /* the level that we register */
RRSOFT_level_des *lev; /* for readableness only */
PID i;
printk("RRSOFT_register_level\n");
/* request an entry in the level_table */
l = level_alloc_descriptor(sizeof(RRSOFT_level_des));
lev = (RRSOFT_level_des *)level_table[l];
printk(" lev=%d\n",(int)lev);
/* fill the standard descriptor */
lev->l.public_scheduler = RRSOFT_public_scheduler;
lev->l.public_create = RRSOFT_public_create;
lev->l.public_end = RRSOFT_public_end;
lev->l.public_dispatch = RRSOFT_public_dispatch;
lev->l.public_epilogue = RRSOFT_public_epilogue;
lev->l.public_activate = RRSOFT_public_activate;
lev->l.public_unblock = RRSOFT_public_unblock;
lev->l.public_block = RRSOFT_public_block;
lev->l.public_message = RRSOFT_public_message;
/* fill the RRSOFT descriptor part */
for (i = 0; i < MAX_PROC; i++) {
lev->nact[i] = -1;
NULL_TIMESPEC(&lev->reactivation_time[i]);
lev->reactivation_timer[i] = -1;
lev->periodic[i] = 0;
lev->period[i] = 0;
}
iq_init(&lev->ready, &freedesc, 0);
if (slice < RRSOFT_MINIMUM_SLICE) slice = RRSOFT_MINIMUM_SLICE;
if (slice > RRSOFT_MAXIMUM_SLICE) slice = RRSOFT_MAXIMUM_SLICE;
lev->slice = slice;
lev->multiboot = mb;
lev->models = models;
if (createmain)
sys_atrunlevel(RRSOFT_call_main,(void *) l, RUNLEVEL_INIT);
return l;
}