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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 1.5 2003-12-17 13:52:45 giacomo Exp $

 File:        $File$

 Revision:    $Revision: 1.5 $

 Last update: $Date: 2003-12-17 13:52:45 $

 ------------

**/

/*

 * 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;

}