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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: cash.c,v 1.1 2004-06-01 11:42:40 giacomo Exp $

 File:        $File$

 Revision:    $Revision: 1.1 $

 Last update: $Date: 2004-06-01 11:42:40 $

 ------------

 This file contains the aperiodic server CBS (Total Bandwidth Server)

 Read CBS.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 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 "cash.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>

/*+ Status used in the level +*/

#define CBSGHD_IDLE          APER_STATUS_BASE   /*+ waiting the activation +*/

#define CBSGHD_ZOMBIE        APER_STATUS_BASE+1 /*+ waiting the period end +*/

/* structure of an element of the capacity queue  */

struct cap_queue {

  int              cap;

  struct timespec  dead;

  struct cap_queue *next;

};

/*+ the level redefinition for the CBS_HD level +*/

typedef struct {

  level_des l;     /*+ the standard level descriptor          +*/

  /* The wcet are stored in the task descriptor, but we need

     an array for the deadlines. We can't use the timespec_priority

     field because it is used by the master level!!!...

     Notice that however the use of the timespec_priority field

     does not cause any problem...                     */

  struct timespec cbsghd_dline[MAX_PROC]; /*+ CBSGHD deadlines      +*/

  TIME period[MAX_PROC]; /*+ CBSGHD activation period            +*/

  TIME maxperiod[MAX_PROC]; /*+ maximum period of each elastic task    +*/

  int cremaining[MAX_PROC]; /*+ instance remaining computation time +*/

  TIME act_period[MAX_PROC]; /*+ actual period of each elastic task: it

                               must be less than maxperiod!!!        +*/

  struct timespec request_time[MAX_PROC]; /* used for the response time */

  TIME last_response_time[MAX_PROC]; /* response time of the last instance */

  TIME cnormal[MAX_PROC]; /*+ CBSGHD normal computation time    +*/

  struct timespec reactivation_time[MAX_PROC];

        /*+ the time at witch  the reactivation timer is post +*/

  int reactivation_timer[MAX_PROC];

                                   /*+ the recativation timer +*/

  struct cap_queue *queue;         /* pointer to the spare capacity queue */

  int flags;       /*+ the init flags...                      +*/

  bandwidth_t U;   /*+ the used bandwidth by the server       +*/

  int idle;         /* the idle flag...  */

  struct timespec start_idle; /*gives the start time of the last idle period */

  LEVEL scheduling_level;

} CBSGHD_level_des;

/* insert a capacity in the queue capacity ordering by deadline */

static int c_insert(struct timespec dead, int cap, struct cap_queue **que,

                     PID p)

{

  struct cap_queue *prev, *n, *new;

    prev = NULL;

    n = *que;

    while ((n != NULL) &&

           !TIMESPEC_A_LT_B(&dead, &n->dead)) {

        prev = n;

        n = n->next;

    }

    new = (struct cap_queue *)kern_alloc(sizeof(struct cap_queue));

    if (new == NULL) {

      kern_printf("\nNew cash_queue element failed\n");

      kern_raise(XINVALID_TASK, p);

      return -1;

    }

    new->next = NULL;

    new->cap = cap;

    new->dead = dead;

    if (prev != NULL)

      prev->next = new;

    else

      *que = new;

    if (n != NULL)

      new->next = n;

    return 0;

}

/* extract the first element from the capacity queue */

static int c_extractfirst(struct cap_queue **que)

{

    struct cap_queue *p = *que;

    if (*que == NULL) return(-1);

    *que = (*que)->next;

    kern_free(p, sizeof(struct cap_queue));

    return(1);

}

/* read data of the first element from the capacity queue */

static void c_readfirst(struct timespec *d, int *c, struct cap_queue *que)

{

    *d = que->dead;

    *c = que->cap;

}

/* write data of the first element from the capacity queue */

static void c_writefirst(struct timespec dead, int cap, struct cap_queue *que)

{

    que->dead = dead;

    que->cap = cap;

}

static void CBSGHD_activation(CBSGHD_level_des *lev,

                             PID p,

                             struct timespec *acttime)

{

  JOB_TASK_MODEL job;

  /* This rule is used when we recharge the budget at initial task activation

     and each time a new task instance must be activated  */

  if (TIMESPEC_A_GT_B(acttime, &lev->cbsghd_dline[p])) {

    /* we modify the deadline ... */

    TIMESPEC_ASSIGN(&lev->cbsghd_dline[p], acttime);

  }

  lev->act_period[p] = 0;

  if (proc_table[p].avail_time > 0)

    proc_table[p].avail_time = 0;

  /* there is a while because if the wcet is << than the system tick

     we need to postpone the deadline many times */

  while (proc_table[p].avail_time <= 0) {

    /* A spare capacity is inserted in the capacity queue!! */

    ADDUSEC2TIMESPEC(lev->period[p], &lev->cbsghd_dline[p]);

    lev->act_period[p] += lev->period[p];

    c_insert(lev->cbsghd_dline[p], lev->cnormal[p], &lev->queue, p);

    /* it exploits available capacities from the capacity queue */

    while (proc_table[p].avail_time < (int)lev->cnormal[p] &&

           lev->queue != NULL) {

      struct timespec dead;

      int             cap, delta;

      delta = lev->cnormal[p] - proc_table[p].avail_time;

      c_readfirst(&dead, &cap, lev->queue);

      if (!TIMESPEC_A_GT_B(&dead, &lev->cbsghd_dline[p])) {

        if (cap > delta) {

          proc_table[p].avail_time += delta;

          c_writefirst(dead, cap - delta, lev->queue);

        }

        else {

          proc_table[p].avail_time += cap;

          c_extractfirst(&lev->queue);

        }

      }

      else

        break;

    }

  }

  lev->cremaining[p] = proc_table[p].wcet - proc_table[p].avail_time;

#ifdef TESTG

  if (starttime && p == 3) {

    oldx = x;

    x = ((lev->cbsghd_dline[p].tv_sec*1000000+lev->cbsghd_dline[p].tv_nsec/1000)/5000 - starttime) + 20;

    //      kern_printf("(a%d)",lev->cbsghd_dline[p].tv_sec*1000000+lev->cbsghd_dline[p].tv_nsec/1000);

    if (oldx > x) sys_end();

    if (x<640)

      grx_plot(x, 15, 8);

  }

#endif

  /* and, finally, we reinsert the task in the master level */

  job_task_default_model(job, lev->cbsghd_dline[p]);

  job_task_def_yesexc(job);

  level_table[ lev->scheduling_level ]->

    private_insert(lev->scheduling_level, p, (TASK_MODEL *)&job);

}

/* this is the periodic reactivation of the task... */

static void CBSGHD_timer_reactivate(void *par)

{

  PID p = (PID) par;

  CBSGHD_level_des *lev;

  lev = (CBSGHD_level_des *)level_table[proc_table[p].task_level];

  if (proc_table[p].status == CBSGHD_IDLE) {

    /* the task has finished the current activation and must be

       reactivated */

    /* request_time represents the time of the last instance release!! */

    TIMESPEC_ASSIGN(&lev->request_time[p], &lev->reactivation_time[p]);

    /* If idle=1, then we have to discharge the capacities stored in

       the capacity queue up to the length of the idle interval */

    if (lev->idle == 1) {

      TIME interval;

      struct timespec delta;

      lev->idle = 0;

      SUBTIMESPEC(&lev->request_time[p], &lev->start_idle, &delta);

      /* length of the idle interval expressed in usec! */

      interval = TIMESPEC2NANOSEC(&delta) / 1000;

      /* it discharge the available capacities from the capacity queue */

      while (interval > 0 && lev->queue != NULL) {

        struct timespec dead;

        int             cap;

        c_readfirst(&dead, &cap, lev->queue);

        if (cap > interval) {

          c_writefirst(dead, cap - interval, lev->queue);

          interval = 0;

        }

        else {

          interval -= cap;

          c_extractfirst(&lev->queue);

        }      

      }

    }

    CBSGHD_activation(lev,p,&lev->reactivation_time[p]);

    /* check the constraint on the maximum period permitted... */

    if (lev->act_period[p] > lev->maxperiod[p]) {

      kern_printf("Deadline miss(timer_react.! process:%d act_period:%lu maxperiod:%lu\n",

                  p, lev->act_period[p], lev->maxperiod[p]);

      kern_raise(XDEADLINE_MISS,p);

    }

    /* Set the reactivation timer */

    TIMESPEC_ASSIGN(&lev->reactivation_time[p], &lev->cbsghd_dline[p]);

    lev->reactivation_timer[p] = kern_event_post(&lev->reactivation_time[p],

                                                 CBSGHD_timer_reactivate,

                                                 (void *)p);

    event_need_reschedule();

  }

  else {

    /* this situation cannot occur */

    kern_printf("Trying to reactivate a task which is not IDLE!!!/n");

    kern_raise(XINVALID_TASK,p);

  }

}

static void CBSGHD_avail_time_check(CBSGHD_level_des *lev, PID p)

{

  /*+ if the capacity became negative the remaining computation time

    is diminuished.... +*/

  /* if (p==4)

    kern_printf("(old dead:%d av_time:%d crem:%d)\n",

                lev->cbsghd_dline[p].tv_sec*1000000+

                lev->cbsghd_dline[p].tv_nsec/1000, proc_table[p].avail_time,

                lev->cremaining[p]);  */

  if (proc_table[p].avail_time < 0)

    lev->cremaining[p] += proc_table[p].avail_time;

  if (lev->cremaining[p] <= 0) {

    kern_printf("Task:%d   WCET violation \n", p);

    kern_raise(XWCET_VIOLATION, p);

    ll_abort(666);

  }

  /* there is a while because if the wcet is << than the system tick

     we need to postpone the deadline many times */

  while (proc_table[p].avail_time <= 0) {

    /* it exploits available capacities from the capacity queue */

    while (proc_table[p].avail_time < lev->cremaining[p]

           && lev->queue != NULL) {

      struct timespec dead;

      int             cap, delta;

      delta = lev->cremaining[p] - proc_table[p].avail_time;

      c_readfirst(&dead, &cap, lev->queue);

      if (!TIMESPEC_A_GT_B(&dead, &lev->cbsghd_dline[p])) {

        if (cap > delta) {

          proc_table[p].avail_time += delta;

          c_writefirst(dead, cap - delta, lev->queue);

        }

        else {

          proc_table[p].avail_time += cap;

          c_extractfirst(&lev->queue);

        }

      }

      else

        break;

    }

    /* if (p==5 && proc_table[p].avail_time <= 0 &&

       lev->cremaining[p] > lev->cnormal[p])

       kern_printf("(inter dead:%d av_time:%d crem:%d)\n",

       lev->cbsghd_dline[p].tv_sec*1000000+

       lev->cbsghd_dline[p].tv_nsec/1000, proc_table[p].avail_time,

       lev->cremaining[p]); */

    /* The remaining computation time is modified according

       to the new budget! */

    if (proc_table[p].avail_time > 0)

      lev->cremaining[p] -= proc_table[p].avail_time;

    else {

      /* the CBSGHD rule for recharging the capacity:  */

      if (lev->cremaining[p] > lev->cnormal[p]) {

        ADDUSEC2TIMESPEC(lev->period[p], &lev->cbsghd_dline[p]);

        lev->act_period[p] += lev->period[p];

        /* A spare capacity is inserted in the capacity queue!! */

        c_insert(lev->cbsghd_dline[p], lev->cnormal[p], &lev->queue, p);

      }

      else {

        TIME t;

        t = (lev->cremaining[p] * lev->period[p]) / lev->cnormal[p];

        ADDUSEC2TIMESPEC(t, &lev->cbsghd_dline[p]);

        lev->act_period[p] += t;

        /* A spare capacity is inserted in the capacity queue!! */

        c_insert(lev->cbsghd_dline[p], lev->cremaining[p], &lev->queue, p);

      }

    }

  }

  /*  if (p==4)

    kern_printf("n dead:%d av_time:%d crem:%d)\n",

                lev->cbsghd_dline[p].tv_sec*1000000+

                lev->cbsghd_dline[p].tv_nsec/1000, proc_table[p].avail_time,

                lev->cremaining[p]);  */

  /* check the constraint on the maximum period permitted... */

  if (lev->act_period[p] > lev->maxperiod[p]) {

    /*kern_printf("n dead:%d av_time:%d crem:%d)\n",

                lev->cbsghd_dline[p].tv_sec*1000000+

                lev->cbsghd_dline[p].tv_nsec/1000, proc_table[p].avail_time,

                lev->cremaining[p]);  */

    kern_printf("Deadline miss(av.time_check! process:%d act_period:%lu maxperiod:%lu\n",

                p, lev->act_period[p], lev->maxperiod[p]);

    kern_raise(XDEADLINE_MISS,p);

  }

  if (TIMESPEC_A_LT_B(&lev->reactivation_time[p], &lev->cbsghd_dline[p])) {

    /* we delete the reactivation timer */

    kern_event_delete(lev->reactivation_timer[p]);

    /* repost the event at the next instance deadline... */

    lev->reactivation_time[p] = lev->cbsghd_dline[p];

    lev->reactivation_timer[p] = kern_event_post(&lev->reactivation_time[p],

                                                 CBSGHD_timer_reactivate,

                                                 (void *)p);

  }

#ifdef TESTG

  if (starttime && p == 3) {

    oldx = x;

    x = ((lev->cbsghd_dline[p].tv_sec*1000000+

          lev->cbsghd_dline[p].tv_nsec/1000)/5000 - starttime) + 20;

    //      kern_printf("(e%d avail%d)",lev->cbsghd_dline[p].tv_sec*1000000+

                        lev->cbsghd_dline[p].tv_nsec/1000,proc_table[p].avail_time);

    if (oldx > x) sys_end();

    if (x<640)

      grx_plot(x, 15, 2);

  }

#endif

}

/*+ this function is called when a killed or ended task reach the

  period end +*/

static void CBSGHD_timer_zombie(void *par)

{

  PID p = (PID) par;

  CBSGHD_level_des *lev;

  lev = (CBSGHD_level_des *)level_table[proc_table[p].task_level];

  /* we finally put the task in the FREE status */

  proc_table[p].status = FREE;

  iq_insertfirst(p,&freedesc);

  /* and free the allocated bandwidth */

  lev->U -= (MAX_BANDWIDTH/lev->period[p]) * lev->cnormal[p];

}

static PID CBSGHD_public_scheduler(LEVEL l)

{

  CBSGHD_level_des *lev = (CBSGHD_level_des *)(level_table[l]);

  /* it stores the actual time and set the IDLE flag in order to handle

     the capacity queue discharging!!! */

  lev->idle = 1;

  kern_gettime(&lev->start_idle);

  /* the CBSGHD don't schedule anything...

     it's an EDF level or similar that do it! */

  return NIL;

}

/* The on-line guarantee is enabled only if the appropriate flag is set... */

static int CBSGHD_public_guarantee(LEVEL l, bandwidth_t *freebandwidth)

{

  CBSGHD_level_des *lev = (CBSGHD_level_des *)(level_table[l]);

  if (lev->flags & CBSGHD_FAILED_GUARANTEE) {

    *freebandwidth = 0;

    //kern_printf("guarantee :garanzia fallita!!!!!!\n");

    return 0;

  }

  else if (*freebandwidth >= lev->U) {

    *freebandwidth -= lev->U;

    return 1;

  }

  else {

    //kern_printf("guarantee :garanzia fallita per mancanza di banda!!!!!!\n");

    //kern_printf("freeband: %d request band: %d", *freebandwidth, lev->U);

    return 0;

  }

}

static int CBSGHD_public_create(LEVEL l, PID p, TASK_MODEL *m)

{

  CBSGHD_level_des *lev = (CBSGHD_level_des *)(level_table[l]);

  ELASTIC_HARD_TASK_MODEL *s;

  bandwidth_t b1, b2;

  if (m->pclass != ELASTIC_HARD_PCLASS) return -1;

  if (m->level != 0 && m->level != l) return -1;

  s = (ELASTIC_HARD_TASK_MODEL *)m;

  /*  kern_printf("accept :ELASTIC TASK found!!!!!!\n"); */

  b1 = (MAX_BANDWIDTH / s->period) * s->cnormal;

  b2 = (MAX_BANDWIDTH / s->maxperiod) * s->wcet;

  if (!(s->wcet && s->cnormal && s->period && s->maxperiod &&

        s->wcet >= s->cnormal && b1 >= b2) )

    return -1;

  /*  kern_printf("period: %d maxperiod: %d cnormal: %d wcet: %d, b1: %d b2:

      %d\n", s->period, s->maxperiod, s->cnormal, s->wcet, b1, b2); */

  /* now we know that m is a valid model */

  /* Enable wcet check */

  proc_table[p].avail_time = 0;

  proc_table[p].wcet       = s->wcet;

  proc_table[p].control   |= CONTROL_CAP;

  lev->period[p] = s->period;

  lev->maxperiod[p] = s->maxperiod;

  lev->cnormal[p] = s->cnormal;

  NULL_TIMESPEC(&lev->cbsghd_dline[p]);

  NULL_TIMESPEC(&lev->request_time[p]);

  /* update the bandwidth... */

  if (lev->flags & CBSGHD_ENABLE_GUARANTEE) {

    bandwidth_t b;

    b = (MAX_BANDWIDTH / s->period) * s->cnormal;

    /* 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)...

         (see EDF.c) */

      lev->flags |= CBSGHD_FAILED_GUARANTEE;

  }

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

}

static void CBSGHD_public_detach(LEVEL l, PID p)

{

  /* the CBSGHD level doesn't introduce any dinamic allocated new field.

     we have only to reset the NO_GUARANTEE FIELD and decrement the allocated

     bandwidth */

  CBSGHD_level_des *lev = (CBSGHD_level_des *)(level_table[l]);

  if (lev->flags & CBSGHD_FAILED_GUARANTEE)

    lev->flags &= ~CBSGHD_FAILED_GUARANTEE;

  else

    lev->U -= (MAX_BANDWIDTH / lev->period[p]) * lev->cnormal[p];

}

static void CBSGHD_public_dispatch(LEVEL l, PID p, int nostop)

{

  CBSGHD_level_des *lev = (CBSGHD_level_des *)(level_table[l]);

  level_table[ lev->scheduling_level ]->

    private_dispatch(lev->scheduling_level,p,nostop);

}

static void CBSGHD_public_epilogue(LEVEL l, PID p)

{

  CBSGHD_level_des *lev = (CBSGHD_level_des *)(level_table[l]);

  JOB_TASK_MODEL job;

  /* check if the budget is finished... */

  if ( proc_table[p].avail_time <= 0) {

    /* we kill the current activation */

    level_table[ lev->scheduling_level ]->

      private_extract(lev->scheduling_level, p);

    /* we modify the deadline */

    CBSGHD_avail_time_check(lev, p);

    /* and, finally, we reinsert the task in the master level */

    job_task_default_model(job, lev->cbsghd_dline[p]);

    job_task_def_yesexc(job);

    level_table[ lev->scheduling_level ]->

      private_insert(lev->scheduling_level, p, (TASK_MODEL *)&job);

    //    kern_printf("epil : dl %d per %d p %d |\n",

                      //              lev->cbsghd_dline[p].tv_nsec/1000,lev->period[p],p);

  }

  else

    /* the task has been preempted. it returns into the ready queue by

       calling the guest_epilogue... */

    level_table[ lev->scheduling_level ]->

      private_epilogue(lev->scheduling_level,p);

}

static void CBSGHD_public_activate(LEVEL l, PID p)

{

  CBSGHD_level_des *lev = (CBSGHD_level_des *)(level_table[l]);

  kern_gettime(&lev->request_time[p]);

  /* If idle=1, then we have to discharge the capacities stored in

     the capacity queue up to the length of the idle interval */

  if (lev->idle == 1) {

    TIME interval;

    struct timespec delta;

    lev->idle = 0;

    SUBTIMESPEC(&lev->request_time[p], &lev->start_idle, &delta);

    /* length of the idle interval expressed in usec! */

    interval = TIMESPEC2NANOSEC(&delta) / 1000;

    /* it discharge the available capacities from the capacity queue */

    while (interval > 0 && lev->queue != NULL) {

      struct timespec dead;

      int             cap;

      c_readfirst(&dead, &cap, lev->queue);

      if (cap > interval) {

        c_writefirst(dead, cap - interval, lev->queue);

        interval = 0;

      }

      else {

        interval -= cap;

        c_extractfirst(&lev->queue);

      }

    }

  }

  CBSGHD_activation(lev, p, &lev->request_time[p]);

  /* check the constraint on the maximum period permitted... */

  if (lev->act_period[p] > lev->maxperiod[p]) {

      kern_printf("Deadline miss(task_activ.! process:%d act_period:%lu maxperiod:%lu\n",

                  p, lev->act_period[p], lev->maxperiod[p]);

    kern_raise(XDEADLINE_MISS,p);

  }

  /* Set the reactivation timer */

  TIMESPEC_ASSIGN(&lev->reactivation_time[p], &lev->cbsghd_dline[p]);

  lev->reactivation_timer[p] = kern_event_post(&lev->reactivation_time[p],

                                                   CBSGHD_timer_reactivate,

                                                   (void *)p);

  //  kern_printf("act : %d %d |",lev->cbsghd_dline[p].tv_nsec/1000,p);

}

static void CBSGHD_public_unblock(LEVEL l, PID p)

{

  printk("CBSGHD_task_insert\n");

  kern_raise(XINVALID_TASK,p);

}

static void CBSGHD_public_block(LEVEL l, PID p)

{

  printk("CBSGHD_task_extract\n");

  kern_raise(XINVALID_TASK,p);

}

static int CBSGHD_public_message(LEVEL l, PID p, void *m)

{

  CBSGHD_level_des *lev = (CBSGHD_level_des *)(level_table[l]);

  struct timespec act_time, res;

  /* It computes the response time of the current instance... */

  kern_gettime(&act_time);

  SUBTIMESPEC(&act_time, &lev->request_time[p], &res);

  /* response time expressed in usec! */

  lev->last_response_time[p] = TIMESPEC2NANOSEC(&res) / 1000;

  level_table[ lev->scheduling_level ]->

    private_extract(lev->scheduling_level,p);

  /* A spare capacity is inserted in the capacity queue!! */

  if (proc_table[p].avail_time > 0) {

    c_insert(lev->cbsghd_dline[p], proc_table[p].avail_time, &lev->queue, p);

    proc_table[p].avail_time = 0;

  }  

  proc_table[p].status = CBSGHD_IDLE;

  jet_update_endcycle(); /* Update the Jet data... */

  return 0;

}

static void CBSGHD_public_end(LEVEL l, PID p)

{

  CBSGHD_level_des *lev = (CBSGHD_level_des *)(level_table[l]);

  /* check if the capacity became negative... */

  /* there is a while because if the wcet is << than the system tick

     we need to postpone the deadline many times */

  while (proc_table[p].avail_time < 0) {

    /* the CBSGHD rule for recharging the capacity */

    proc_table[p].avail_time += lev->cnormal[p];

    ADDUSEC2TIMESPEC(lev->period[p], &lev->cbsghd_dline[p]);

  }

  level_table[ lev->scheduling_level ]->

    private_extract(lev->scheduling_level,p);

  /* we delete the reactivation timer */

  kern_event_delete(lev->reactivation_timer[p]);

  lev->reactivation_timer[p] = -1;

  /* Finally, we post the zombie event. when the end period is reached,

     the task descriptor and banwidth are freed */

  proc_table[p].status = CBSGHD_ZOMBIE;

  lev->reactivation_timer[p] = kern_event_post(&lev->cbsghd_dline[p],

                                               CBSGHD_timer_zombie,

                                               (void *)p);

}

/* Registration functions */

/*+ Registration function:

    int flags                 the init flags ... see CBS.h +*/

LEVEL CBSGHD_register_level(int flags, LEVEL master)

{

  LEVEL l;            /* the level that we register */

  CBSGHD_level_des *lev;  /* for readableness only */

  PID i;              /* a counter */

  printk("CBSGHD_register_level\n");

  /* request an entry in the level_table */

  l = level_alloc_descriptor(sizeof(CBSGHD_level_des));

  lev = (CBSGHD_level_des *)level_table[l];

  printk("    lev=%d\n",(int)lev);

  /* fill the standard descriptor */

  lev->l.public_scheduler = CBSGHD_public_scheduler;

  if (flags & CBSGHD_ENABLE_GUARANTEE)

    lev->l.public_guarantee = CBSGHD_public_guarantee;

  else

    lev->l.public_guarantee = NULL;

  lev->l.public_create    = CBSGHD_public_create;

  lev->l.public_detach    = CBSGHD_public_detach;

  lev->l.public_end       = CBSGHD_public_end;

  lev->l.public_dispatch  = CBSGHD_public_dispatch;

  lev->l.public_epilogue  = CBSGHD_public_epilogue;

  lev->l.public_activate  = CBSGHD_public_activate;

  lev->l.public_unblock   = CBSGHD_public_unblock;

  lev->l.public_block     = CBSGHD_public_block;

  lev->l.public_message   = CBSGHD_public_message;

  /* fill the CBSGHD descriptor part */

  for (i=0; i<MAX_PROC; i++) {

     NULL_TIMESPEC(&lev->cbsghd_dline[i]);

     lev->period[i] = 0;

     NULL_TIMESPEC(&lev->request_time[i]);

     lev->last_response_time[i] = 0;

     NULL_TIMESPEC(&lev->reactivation_time[i]);

     lev->reactivation_timer[i] = -1;

  }

  lev->U = 0;

  lev->idle = 0;

  lev->queue = NULL;

  lev->scheduling_level = master;

  lev->flags = flags & 0x07;

  return l;

}