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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 2004-06-04 10:48:28 giacomo Exp $

 File:        $File$
 Revision:    $Revision: 1.1 $
 Last update: $Date: 2004-06-04 10:48:28 $
 ------------
**/

/*
 * 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>
#include <kernel/trace.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                            +*/

  QUEUE 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)
{
  TIMESPEC_ASSIGN(&proc_table[p].timespec_priority,
                  &proc_table[p].request_time);
  ADDUSEC2TIMESPEC(lev->period[p], &proc_table[p].timespec_priority);

  TIMESPEC_ASSIGN(&lev->deadline_timespec[p],
                  &proc_table[p].timespec_priority);

  /* Insert task in the correct position */
  proc_table[p].status = EDFACT_READY;
  q_timespec_insert(p,&lev->ready);

  /* needed because when there is a wcet miss I disable CONTROL_CAP */
  proc_table[p].control |= CONTROL_CAP;
}

static char *EDFACT_status_to_a(WORD status)
{
  if (status < MODULE_STATUS_BASE)
    return status_to_a(status);

  switch (status) {
    case EDFACT_READY        : return "EDFACT_Ready";
    case EDFACT_IDLE         : return "EDFACT_Idle";
    default               : return "EDFACT_Unknown";
  }
}

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);
      TIMESPEC_ASSIGN(&proc_table[p].request_time,
                      &proc_table[p].timespec_priority);

      EDFACT_internal_activate(lev,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);
}

static int EDFACT_level_accept_task_model(LEVEL l, TASK_MODEL *m)
{
  if (m->pclass == HARD_PCLASS || m->pclass == (HARD_PCLASS | l)) {
    HARD_TASK_MODEL *h = (HARD_TASK_MODEL *)m;

    if (h->wcet && h->mit && h->periodicity == PERIODIC)
      return 0;
  }

  return -1;
}

static int EDFACT_level_accept_guest_model(LEVEL l, TASK_MODEL *m)
{
  if (m->pclass == JOB_PCLASS || m->pclass == (JOB_PCLASS | l))
    return 0;
  else
    return -1;
}


static char *onoff(int i)
{
  if (i)
    return "On ";
  else
    return "Off";
}

static void EDFACT_level_status(LEVEL l)
{
  EDFACT_level_des *lev = (EDFACT_level_des *)(level_table[l]);
  PID p = lev->ready;

  kern_printf("On-line guarantee : %s\n",
            onoff(lev->flags & EDFACT_ENABLE_GUARANTEE));
  kern_printf("Used Bandwidth    : %u/%u\n",
            lev->U, MAX_BANDWIDTH);

  while (p != NIL) {
    if ((proc_table[p].pclass) == JOB_PCLASS)
      kern_printf("Pid: %2d (GUEST)\n", p);
    else
      kern_printf("Pid: %2d Name: %10s %s: %9d Dline: %9d.%6d Stat: %s\n",
              p,
              proc_table[p].name,
              "Period  ",
              lev->period[p],
              proc_table[p].timespec_priority.tv_sec,
              proc_table[p].timespec_priority.tv_nsec/1000,
              EDFACT_status_to_a(proc_table[p].status));
    p = proc_table[p].next;
  }

  for (p=0; p<MAX_PROC; p++)
    if (proc_table[p].task_level == l && proc_table[p].status != EDFACT_READY
        && proc_table[p].status != FREE )
      kern_printf("Pid: %2d Name: %10s %s: %9d Dline: %9d.%6d Stat: %s\n",
                p,
                proc_table[p].name,
                "Period  ",
                lev->period[p],
                proc_table[p].timespec_priority.tv_sec,
                proc_table[p].timespec_priority.tv_nsec/1000,
                EDFACT_status_to_a(proc_table[p].status));
}

/* The scheduler only gets the first task in the queue */
static PID EDFACT_level_scheduler(LEVEL l)
{
  EDFACT_level_des *lev = (EDFACT_level_des *)(level_table[l]);

/*  {  // print 4 dbg the ready queue
    PID p= lev->ready;
    kern_printf("(s");
    while (p != NIL) {
      kern_printf("%d ",p);
      p = proc_table[p].next;
    }
    kern_printf(") ");
  }
  */
  return (PID)lev->ready;
}

/* The on-line guarantee is enabled only if the appropriate flag is set... */
static int EDFACT_level_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_task_create(LEVEL l, PID p, TASK_MODEL *m)
{
  EDFACT_level_des *lev = (EDFACT_level_des *)(level_table[l]);

  /* if the EDFACT_task_create is called, then the pclass must be a
     valid pclass. */

  HARD_TASK_MODEL *h = (HARD_TASK_MODEL *)m;

  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_task_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 int EDFACT_task_eligible(LEVEL l, PID p)
{
  return 0; /* if the task p is chosen, it is always eligible */
}

static void EDFACT_task_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!!! */
  q_extract(p, &lev->ready);
}

static void EDFACT_task_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... */
  q_timespec_insert(p,&lev->ready);
  proc_table[p].status = EDFACT_READY;
}

static void EDFACT_task_activate(LEVEL l, PID p)
{
  EDFACT_level_des *lev = (EDFACT_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) {
    /* a periodic task cannot be activated when it is already active */
    kern_raise(XACTIVATION,p);
    return;
  }

  ll_gettime(TIME_EXACT, &proc_table[p].request_time);

  EDFACT_internal_activate(lev,p);

  /* Set the deadline timer */
  lev->deadline_timer[p] = kern_event_post(&lev->deadline_timespec[p],
                                           EDFACT_timer_deadline,
                                           (void *)p);

}

static void EDFACT_task_insert(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;
  q_timespec_insert(p,&lev->ready);
}

static void EDFACT_task_extract(LEVEL l, PID p)
{
}

static void EDFACT_task_endcycle(LEVEL l, PID p)
{
  EDFACT_level_des *lev = (EDFACT_level_des *)(level_table[l]);


  /* 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 */
    ll_gettime(TIME_EXACT, &proc_table[p].request_time);

    EDFACT_internal_activate(lev,p);

    /* check if the deadline has already expired */
    if (TIMESPEC_A_LT_B(&proc_table[p].timespec_priority, &schedule_time)) {
      /* count the deadline miss */
      lev->dline_miss[p]++;
      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, request_time, etc... ) */
  }
}

static void EDFACT_task_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;
  q_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);
    event_delete(lev->deadline_timer[p]);
  }
}

static void EDFACT_task_sleep(LEVEL l, PID p)
{ kern_raise(XUNVALID_TASK,exec_shadow); }

static void EDFACT_task_delay(LEVEL l, PID p, TIME usdelay)
{ kern_raise(XUNVALID_TASK,exec_shadow); }

/* Guest Functions
   These functions manages a JOB_TASK_MODEL, that is used to put
   a guest task in the EDFACT ready queue. */

static int EDFACT_guest_create(LEVEL l, PID p, TASK_MODEL *m)
{
  EDFACT_level_des *lev = (EDFACT_level_des *)(level_table[l]);
  JOB_TASK_MODEL *job = (JOB_TASK_MODEL *)m;

  /* if the EDFACT_guest_create is called, then the pclass must be a
     valid pclass. */

  TIMESPEC_ASSIGN(&proc_table[p].timespec_priority, &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->period[p] = job->period;

  /* there is no bandwidth guarantee at this level, it is performed
     by the level that inserts guest tasks... */

  return 0; /* OK, also if the task cannot be guaranteed... */
}

static void EDFACT_guest_detach(LEVEL l, PID p)
{
  /* the EDFACT level doesn't introduce any dinamic allocated new field.
     No guarantee is performed on guest tasks... so we don't have to reset
     the NO_GUARANTEE FIELD */
}

static void EDFACT_guest_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!!! */
  q_extract(p, &lev->ready);
}

static void EDFACT_guest_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... */
  q_timespec_insert(p,&lev->ready);
  proc_table[p].status = EDFACT_READY;
}

static void EDFACT_guest_activate(LEVEL l, PID p)
{
  EDFACT_level_des *lev = (EDFACT_level_des *)(level_table[l]);

  /* Insert task in the correct position */
  q_timespec_insert(p,&lev->ready);
  proc_table[p].status = EDFACT_READY;

  /* Set the deadline timer */
  if (!(lev->flag[p] & EDFACT_FLAG_NORAISEEXC))
    lev->deadline_timer[p] = kern_event_post(&proc_table[p].timespec_priority,
                                             EDFACT_timer_guest_deadline,
                                             (void *)p);

}

static void EDFACT_guest_insert(LEVEL l, PID p)
{
  EDFACT_level_des *lev = (EDFACT_level_des *)(level_table[l]);

  /* Insert task in the correct position */
  q_timespec_insert(p,&lev->ready);
  proc_table[p].status = EDFACT_READY;
}

static void EDFACT_guest_extract(LEVEL l, PID p)
{
}

static void EDFACT_guest_endcycle(LEVEL l, PID p)
{ kern_raise(XUNVALID_GUEST,exec_shadow); }

static void EDFACT_guest_end(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)
  {
    q_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]);
    event_delete(lev->deadline_timer[p]);
    lev->deadline_timer[p] = NIL;
  }

}

static void EDFACT_guest_sleep(LEVEL l, PID p)
{ kern_raise(XUNVALID_GUEST,exec_shadow); }

static void EDFACT_guest_delay(LEVEL l, PID p, TIME usdelay)
{ kern_raise(XUNVALID_GUEST,exec_shadow); }

/* Registration functions */

/*+ Registration function:
    int flags                 the init flags ... see EDFACT.h +*/
void 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();

  printk("    alloco descrittore %d %d\n",l,(int)sizeof(EDFACT_level_des));

  /* alloc the space needed for the EDFACT_level_des */
  lev = (EDFACT_level_des *)kern_alloc(sizeof(EDFACT_level_des));

  printk("    lev=%d\n",(int)lev);

  /* update the level_table with the new entry */
  level_table[l] = (level_des *)lev;

  /* fill the standard descriptor */
  strncpy(lev->l.level_name,  EDFACT_LEVELNAME, MAX_LEVELNAME);
  lev->l.level_code               = EDFACT_LEVEL_CODE;
  lev->l.level_version            = EDFACT_LEVEL_VERSION;

  lev->l.level_accept_task_model  = EDFACT_level_accept_task_model;
  lev->l.level_accept_guest_model = EDFACT_level_accept_guest_model;
  lev->l.level_status             = EDFACT_level_status;
  lev->l.level_scheduler          = EDFACT_level_scheduler;

  if (flags & EDFACT_ENABLE_GUARANTEE)
    lev->l.level_guarantee        = EDFACT_level_guarantee;
  else
    lev->l.level_guarantee        = NULL;

  lev->l.task_create              = EDFACT_task_create;
  lev->l.task_detach              = EDFACT_task_detach;
  lev->l.task_eligible            = EDFACT_task_eligible;
  lev->l.task_dispatch            = EDFACT_task_dispatch;
  lev->l.task_epilogue            = EDFACT_task_epilogue;
  lev->l.task_activate            = EDFACT_task_activate;
  lev->l.task_insert              = EDFACT_task_insert;
  lev->l.task_extract             = EDFACT_task_extract;
  lev->l.task_endcycle            = EDFACT_task_endcycle;
  lev->l.task_end                 = EDFACT_task_end;
  lev->l.task_sleep               = EDFACT_task_sleep;
  lev->l.task_delay               = EDFACT_task_delay;

  lev->l.guest_create             = EDFACT_guest_create;
  lev->l.guest_detach             = EDFACT_guest_detach;
  lev->l.guest_dispatch           = EDFACT_guest_dispatch;
  lev->l.guest_epilogue           = EDFACT_guest_epilogue;
  lev->l.guest_activate           = EDFACT_guest_activate;
  lev->l.guest_insert             = EDFACT_guest_insert;
  lev->l.guest_extract            = EDFACT_guest_extract;
  lev->l.guest_endcycle           = EDFACT_guest_endcycle;
  lev->l.guest_end                = EDFACT_guest_end;
  lev->l.guest_sleep              = EDFACT_guest_sleep;
  lev->l.guest_delay              = EDFACT_guest_delay;

  /* 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;
  }

  lev->ready = NIL;
  lev->flags = flags & 0x07;
  lev->U     = 0;
}

bandwidth_t EDFACT_usedbandwidth(LEVEL l)
{
  EDFACT_level_des *lev = (EDFACT_level_des *)(level_table[l]);
  if (lev->l.level_code    == EDFACT_LEVEL_CODE &&
      lev->l.level_version == EDFACT_LEVEL_VERSION)
    return lev->U;
  else
    return 0;
}

int EDFACT_get_dline_miss(PID p)
{
  LEVEL l = proc_table[p].task_level;
  EDFACT_level_des *lev = (EDFACT_level_des *)(level_table[l]);
  if (lev->l.level_code    == EDFACT_LEVEL_CODE &&
      lev->l.level_version == EDFACT_LEVEL_VERSION)
    return lev->dline_miss[p];
  else
    return -1;
}

int EDFACT_get_wcet_miss(PID p)
{
  LEVEL l = proc_table[p].task_level;
  EDFACT_level_des *lev = (EDFACT_level_des *)(level_table[l]);
  if (lev->l.level_code    == EDFACT_LEVEL_CODE &&
      lev->l.level_version == EDFACT_LEVEL_VERSION)
    return lev->wcet_miss[p];
  else
    return -1;
}

int EDFACT_get_nact(PID p)
{
  LEVEL l = proc_table[p].task_level;
  EDFACT_level_des *lev = (EDFACT_level_des *)(level_table[l]);
  if (lev->l.level_code    == EDFACT_LEVEL_CODE &&
      lev->l.level_version == EDFACT_LEVEL_VERSION)
    return lev->nact[p];
  else
    return -1;
}

int EDFACT_reset_dline_miss(PID p)
{
  LEVEL l = proc_table[p].task_level;
  EDFACT_level_des *lev = (EDFACT_level_des *)(level_table[l]);
  if (lev->l.level_code    == EDFACT_LEVEL_CODE &&
      lev->l.level_version == EDFACT_LEVEL_VERSION)
  {
    lev->dline_miss[p] = 0;
    return 0;
  }
  else
    return -1;
}

int EDFACT_reset_wcet_miss(PID p)
{
  LEVEL l = proc_table[p].task_level;
  EDFACT_level_des *lev = (EDFACT_level_des *)(level_table[l]);
  if (lev->l.level_code    == EDFACT_LEVEL_CODE &&
      lev->l.level_version == EDFACT_LEVEL_VERSION)
  {
    lev->wcet_miss[p] = 0;
    return 0;
  }
  else
    return -1;
}


void EDFACT_modify_dline(PID p, TIME period, int wcet)
{
  EDFACT_level_des *lev = (EDFACT_level_des *)(level_table[proc_table[p].task_level]);

  lev->period[p] = period;
//  lev->wcet[p] = wcet;
  proc_table[p].wcet =wcet;
}