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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>
* (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: edfact.c,v 1.1.1.1 2004-05-24 17:54:51 giacomo Exp $
File: $File$
Revision: $Revision: 1.1.1.1 $
Last update: $Date: 2004-05-24 17:54:51 $
------------
**/
/*
* Copyright (C) 2001 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 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
*
*/
#include "edfact.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>
//#define edfact_printf kern_printf
#define edfact_printf printk
/*+ Status used in the level +*/
#define EDFACT_READY MODULE_STATUS_BASE /*+ - Ready status +*/
#define EDFACT_IDLE MODULE_STATUS_BASE+4 /*+ to wait the deadline +*/
/*+ flags +*/
#define EDFACT_FLAG_NORAISEEXC 2
/*+ the level redefinition for the Earliest Deadline First level +*/
typedef struct {
level_des l; /*+ the standard level descriptor +*/
TIME period[MAX_PROC]; /*+ The task periods; the deadlines are
stored in the priority field +*/
int deadline_timer[MAX_PROC];
/*+ The task deadline timers +*/
struct timespec deadline_timespec[MAX_PROC];
int dline_miss[MAX_PROC]; /*+ Deadline miss counter +*/
int wcet_miss[MAX_PROC]; /*+ Wcet miss counter +*/
int nact[MAX_PROC]; /*+ Wcet miss counter +*/
int flag[MAX_PROC];
/*+ used to manage the JOB_TASK_MODEL and the
periodicity +*/
IQUEUE ready; /*+ the ready queue +*/
int flags; /*+ the init flags... +*/
bandwidth_t U; /*+ the used bandwidth +*/
} EDFACT_level_des;
static void EDFACT_timer_deadline(void *par);
static void EDFACT_internal_activate(EDFACT_level_des *lev, PID p,
struct timespec *t)
{
struct timespec *temp;
temp = iq_query_timespec(p, &lev->ready);
TIMESPEC_ASSIGN(temp,t);
ADDUSEC2TIMESPEC(lev->period[p], temp);
TIMESPEC_ASSIGN(&lev->deadline_timespec[p],
temp);
/* Insert task in the correct position */
proc_table[p].status = EDFACT_READY;
iq_timespec_insert(p,&lev->ready);
/* needed because when there is a wcet miss I disable CONTROL_CAP */
proc_table[p].control |= CONTROL_CAP;
}
static void EDFACT_timer_deadline(void *par)
{
PID p = (PID) par;
EDFACT_level_des *lev;
lev = (EDFACT_level_des *)level_table[proc_table[p].task_level];
switch (proc_table[p].status) {
case EDFACT_IDLE:
edfact_printf("I%d",p);
EDFACT_internal_activate(lev,p, &lev->deadline_timespec[p]);
event_need_reschedule();
break;
default:
edfact_printf("D%d",p);
/* else, a deadline miss occurred!!! */
lev->dline_miss[p]++;
/* the task is into another state */
lev->nact[p]++;
/* Set the deadline timer */
ADDUSEC2TIMESPEC(lev->period[p], &lev->deadline_timespec[p]);
}
/* Set the deadline timer */
lev->deadline_timer[p] = kern_event_post(&lev->deadline_timespec[p],
EDFACT_timer_deadline,
(void *)p);
}
static void EDFACT_timer_guest_deadline(void *par)
{
PID p = (PID) par;
edfact_printf("AAARRRGGGHHH!!!");
kern_raise(XDEADLINE_MISS,p);
}
/* The scheduler only gets the first task in the queue */
static PID EDFACT_public_scheduler(LEVEL l)
{
EDFACT_level_des *lev = (EDFACT_level_des *)(level_table[l]);
return iq_query_first(&lev->ready);
}
/* The on-line guarantee is enabled only if the appropriate flag is set... */
static int EDFACT_public_guarantee(LEVEL l, bandwidth_t *freebandwidth)
{
EDFACT_level_des *lev = (EDFACT_level_des *)(level_table[l]);
if (lev->flags & EDFACT_FAILED_GUARANTEE) {
*freebandwidth = 0;
return 0;
}
else
if (*freebandwidth >= lev->U) {
*freebandwidth -= lev->U;
return 1;
}
else
return 0;
}
static int EDFACT_public_create(LEVEL l, PID p, TASK_MODEL *m)
{
EDFACT_level_des *lev = (EDFACT_level_des *)(level_table[l]);
HARD_TASK_MODEL *h;
if (m->pclass != HARD_PCLASS) return -1;
if (m->level != 0 && m->level != l) return -1;
h = (HARD_TASK_MODEL *)m;
if (!h->wcet || !h->mit || h->periodicity != PERIODIC) return -1;
/* now we know that m is a valid model */
lev->period[p] = h->mit;
lev->flag[p] = 0;
lev->deadline_timer[p] = -1;
lev->dline_miss[p] = 0;
lev->wcet_miss[p] = 0;
lev->nact[p] = 0;
/* Enable wcet check */
proc_table[p].avail_time = h->wcet;
proc_table[p].wcet = h->wcet;
proc_table[p].control |= CONTROL_CAP;
/* update the bandwidth... */
if (lev->flags & EDFACT_ENABLE_GUARANTEE) {
bandwidth_t b;
b = (MAX_BANDWIDTH / h->mit) * h->wcet;
/* really update lev->U, checking an overflow... */
if (MAX_BANDWIDTH - lev->U > b)
lev->U += b;
else
/* The task can NOT be guaranteed (U>MAX_BANDWIDTH)...
in this case, we don't raise an exception... in fact, after the
EDFACT_task_create the task_create will call level_guarantee that return
-1... return -1 in EDFACT_task_create isn't correct, because:
. generally, the guarantee must be done when also the resources
are registered
. returning -1 will cause the task_create to return with an errno
ETASK_CREATE instead of ENO_GUARANTEE!!!
Why I use the flag??? because if the lev->U overflows, if i.e. I set
it to MAX_BANDWIDTH, I lose the correct allocated bandwidth...
*/
lev->flags |= EDFACT_FAILED_GUARANTEE;
}
return 0; /* OK, also if the task cannot be guaranteed... */
}
static void EDFACT_public_detach(LEVEL l, PID p)
{
/* the EDFACT level doesn't introduce any dinamic allocated new field.
we have only to reset the NO_GUARANTEE FIELD and decrement the allocated
bandwidth */
EDFACT_level_des *lev = (EDFACT_level_des *)(level_table[l]);
if (lev->flags & EDFACT_FAILED_GUARANTEE)
lev->flags &= ~EDFACT_FAILED_GUARANTEE;
else
lev->U -= (MAX_BANDWIDTH / lev->period[p]) * proc_table[p].wcet;
}
static void EDFACT_public_dispatch(LEVEL l, PID p, int nostop)
{
EDFACT_level_des *lev = (EDFACT_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 EDFACT_public_epilogue(LEVEL l, PID p)
{
EDFACT_level_des *lev = (EDFACT_level_des *)(level_table[l]);
/* check if the wcet is finished... */
if (proc_table[p].avail_time <= 0 && proc_table[p].control&CONTROL_CAP) {
/* wcet finished: disable wcet event and count wcet miss */
edfact_printf("W%d",p);
proc_table[p].control &= ~CONTROL_CAP;
lev->wcet_miss[p]++;
}
/* the task it returns into the ready queue... */
iq_timespec_insert(p,&lev->ready);
proc_table[p].status = EDFACT_READY;
}
static void EDFACT_public_activate(LEVEL l, PID p)
{
EDFACT_level_des *lev = (EDFACT_level_des *)(level_table[l]);
struct timespec t;
/* Test if we are trying to activate a non sleeping task */
/* save activation (only if needed... */
if (proc_table[p].status != SLEEP) {
/* a periodic task cannot be activated when it is already active */
kern_raise(XACTIVATION,p);
return;
}
kern_gettime(&t);
EDFACT_internal_activate(lev,p, &t);
/* Set the deadline timer */
lev->deadline_timer[p] = kern_event_post(&lev->deadline_timespec[p],
EDFACT_timer_deadline,
(void *)p);
}
static void EDFACT_public_unblock(LEVEL l, PID p)
{
EDFACT_level_des *lev = (EDFACT_level_des *)(level_table[l]);
/* Insert task in the coEDFect position */
proc_table[p].status = EDFACT_READY;
iq_timespec_insert(p,&lev->ready);
}
static void EDFACT_public_block(LEVEL l, PID p)
{
}
static int EDFACT_public_message(LEVEL l, PID p, void *m)
{
EDFACT_level_des *lev = (EDFACT_level_des *)(level_table[l]);
struct timespec t;
/* we reset the capacity counters... */
proc_table[p].avail_time = proc_table[p].wcet;
if (lev->nact[p] > 0) {
edfact_printf("E%d",p);
/* Pending activation: reactivate the thread!!! */
lev->nact[p]--;
/* see also EDFACT_timer_deadline */
kern_gettime(&t);
EDFACT_internal_activate(lev,p, &t);
/* check if the deadline has already expired */
if (TIMESPEC_A_LT_B(iq_query_timespec(p, &lev->ready), &schedule_time)) {
/* count the deadline miss */
lev->dline_miss[p]++;
kern_event_delete(lev->deadline_timer[p]);
}
}
else {
edfact_printf("e%d",p);
/* the task has terminated his job before it consume the wcet. All OK! */
proc_table[p].status = EDFACT_IDLE;
/* when the deadline timer fire, it recognize the situation and set
correctly all the stuffs (like reactivation, etc... ) */
}
jet_update_endcycle(); /* Update the Jet data... */
return 0;
}
static void EDFACT_public_end(LEVEL l, PID p)
{
EDFACT_level_des *lev = (EDFACT_level_des *)(level_table[l]);
edfact_printf("Û%d",p);
/* we finally put the task in the ready queue */
proc_table[p].status = FREE;
iq_insertfirst(p,&freedesc);
/* and free the allocated bandwidth */
lev->U -= (MAX_BANDWIDTH/lev->period[p]) * proc_table[p].wcet;
if (lev->deadline_timer[p] != -1) {
edfact_printf("²%d",p);
kern_event_delete(lev->deadline_timer[p]);
}
}
/* Guest Functions
These functions manages a JOB_TASK_MODEL, that is used to put
a guest task in the EDFACT ready queue. */
static void EDFACT_private_insert(LEVEL l, PID p, TASK_MODEL *m)
{
EDFACT_level_des *lev = (EDFACT_level_des *)(level_table[l]);
JOB_TASK_MODEL *job;
if (m->pclass != JOB_PCLASS || (m->level != 0 && m->level != l) ) {
kern_raise(XINVALID_TASK, p);
return;
}
job = (JOB_TASK_MODEL *)m;
TIMESPEC_ASSIGN(iq_query_timespec(p, &lev->ready), &job->deadline);
lev->deadline_timer[p] = -1;
lev->dline_miss[p] = 0;
lev->wcet_miss[p] = 0;
lev->nact[p] = 0;
if (job->noraiseexc)
lev->flag[p] = EDFACT_FLAG_NORAISEEXC;
else {
lev->flag[p] = 0;
lev->deadline_timer[p] = kern_event_post(iq_query_timespec(p, &lev->ready),
EDFACT_timer_guest_deadline,
(void *)p);
}
lev->period[p] = job->period;
/* Insert task in the correct position */
iq_timespec_insert(p,&lev->ready);
proc_table[p].status = EDFACT_READY;
/* there is no bandwidth guarantee at this level, it is performed
by the level that inserts guest tasks... */
}
static void EDFACT_private_dispatch(LEVEL l, PID p, int nostop)
{
EDFACT_level_des *lev = (EDFACT_level_des *)(level_table[l]);
/* the task state is set to 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 EDFACT_private_epilogue(LEVEL l, PID p)
{
EDFACT_level_des *lev = (EDFACT_level_des *)(level_table[l]);
/* the task has been preempted. it returns into the ready queue... */
iq_timespec_insert(p,&lev->ready);
proc_table[p].status = EDFACT_READY;
}
static void EDFACT_private_extract(LEVEL l, PID p)
{
EDFACT_level_des *lev = (EDFACT_level_des *)(level_table[l]);
//kern_printf("EDFACT_guest_end: dline timer %d\n",lev->deadline_timer[p]);
if (proc_table[p].status == EDFACT_READY)
{
iq_extract(p, &lev->ready);
//kern_printf("(g_end rdy extr)");
}
/* we remove the deadline timer, because the slice is finished */
if (lev->deadline_timer[p] != NIL) {
// kern_printf("EDFACT_guest_end: dline timer %d\n",lev->deadline_timer[p]);
kern_event_delete(lev->deadline_timer[p]);
lev->deadline_timer[p] = NIL;
}
}
/* Registration functions */
/*+ Registration function:
int flags the init flags ... see EDFACT.h +*/
LEVEL EDFACT_register_level(int flags)
{
LEVEL l; /* the level that we register */
EDFACT_level_des *lev; /* for readableness only */
PID i; /* a counter */
printk("EDFACT_register_level\n");
/* request an entry in the level_table */
l = level_alloc_descriptor(sizeof(EDFACT_level_des));
lev = (EDFACT_level_des *)level_table[l];
printk(" lev=%d\n",(int)lev);
/* fill the standard descriptor */
lev->l.private_insert = EDFACT_private_insert;
lev->l.private_extract = EDFACT_private_extract;
lev->l.private_dispatch = EDFACT_private_dispatch;
lev->l.private_epilogue = EDFACT_private_epilogue;
lev->l.public_scheduler = EDFACT_public_scheduler;
if (flags & EDFACT_ENABLE_GUARANTEE)
lev->l.public_guarantee = EDFACT_public_guarantee;
else
lev->l.public_guarantee = NULL;
lev->l.public_create = EDFACT_public_create;
lev->l.public_detach = EDFACT_public_detach;
lev->l.public_end = EDFACT_public_end;
lev->l.public_dispatch = EDFACT_public_dispatch;
lev->l.public_epilogue = EDFACT_public_epilogue;
lev->l.public_activate = EDFACT_public_activate;
lev->l.public_unblock = EDFACT_public_unblock;
lev->l.public_block = EDFACT_public_block;
lev->l.public_message = EDFACT_public_message;
/* fill the EDFACT descriptor part */
for(i=0; i<MAX_PROC; i++) {
lev->period[i] = 0;
lev->deadline_timer[i] = -1;
lev->flag[i] = 0;
lev->dline_miss[i] = 0;
lev->wcet_miss[i] = 0;
lev->nact[i] = 0;
}
iq_init(&lev->ready,&freedesc, 0);
lev->flags = flags & 0x07;
lev->U = 0;
return l;
}
bandwidth_t EDFACT_usedbandwidth(LEVEL l)
{
EDFACT_level_des *lev = (EDFACT_level_des *)(level_table[l]);
return lev->U;
}
int EDFACT_get_dline_miss(PID p)
{
LEVEL l = proc_table[p].task_level;
EDFACT_level_des *lev = (EDFACT_level_des *)(level_table[l]);
return lev->dline_miss[p];
}
int EDFACT_get_wcet_miss(PID p)
{
LEVEL l = proc_table[p].task_level;
EDFACT_level_des *lev = (EDFACT_level_des *)(level_table[l]);
return lev->wcet_miss[p];
}
int EDFACT_get_nact(PID p)
{
LEVEL l = proc_table[p].task_level;
EDFACT_level_des *lev = (EDFACT_level_des *)(level_table[l]);
return lev->nact[p];
}
int EDFACT_reset_dline_miss(PID p)
{
LEVEL l = proc_table[p].task_level;
EDFACT_level_des *lev = (EDFACT_level_des *)(level_table[l]);
lev->dline_miss[p] = 0;
return 0;
}
int EDFACT_reset_wcet_miss(PID p)
{
LEVEL l = proc_table[p].task_level;
EDFACT_level_des *lev = (EDFACT_level_des *)(level_table[l]);
lev->wcet_miss[p] = 0;
return 0;
}