| 0,0 → 1,574 |
|---|
| /* |
| * 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> |
| * Giacomo Guidi <giacomo@gandalf.sssup.it> |
| * [Hard Reservation] |
| * |
| * ReTiS Lab (Scuola Superiore S.Anna - Pisa - Italy) |
| * |
| * http://www.sssup.it |
| * http://retis.sssup.it |
| * http://shark.sssup.it |
| */ |
| |
| /* |
| * 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 <modules/hardcbs.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> |
| |
| /*+ Status used in the level +*/ |
| #define HCBS_IDLE APER_STATUS_BASE /*+ waiting the activation +*/ |
| #define HCBS_ZOMBIE APER_STATUS_BASE+1 /*+ waiting the period end +*/ |
| |
| /*+ task flags +*/ |
| #define HCBS_SAVE_ARRIVALS 1 |
| #define HCBS_APERIODIC 2 |
| #define HCBS_SLEEP 4 |
| #define HCBS_OVERLOAD 8 |
| |
| /*+ the level redefinition for the Total Bandwidth Server 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 cbs_dline[MAX_PROC]; /*+ CBS deadlines +*/ |
| |
| TIME period[MAX_PROC]; /*+ CBS 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 +*/ |
| |
| int nact[MAX_PROC]; /*+ number of pending activations +*/ |
| |
| BYTE flag[MAX_PROC]; /*+ task flags +*/ |
| |
| int flags; /*+ the init flags... +*/ |
| |
| bandwidth_t U; /*+ the used bandwidth by the server +*/ |
| |
| LEVEL scheduling_level; |
| |
| } HCBS_level_des; |
| |
| static void HCBS_activation(HCBS_level_des *lev, |
| PID p, |
| struct timespec *acttime) |
| { |
| JOB_TASK_MODEL job; |
| |
| /* we have to check if the deadline and the wcet are correct before |
| activating a new task or an old task... */ |
| |
| /* check 1: if the deadline is before than the actual scheduling time */ |
| |
| /* check 2: if ( avail_time >= (cbs_dline - acttime)* (wcet/period) ) |
| (rule 7 in the CBS article!) */ |
| TIME t; |
| struct timespec t2,t3; |
| |
| t = (lev->period[p] * proc_table[p].avail_time) / proc_table[p].wcet; |
| t3.tv_sec = t / 1000000; |
| t3.tv_nsec = (t % 1000000) * 1000; |
| |
| SUBTIMESPEC(&lev->cbs_dline[p], acttime, &t2); |
| |
| if (/* 1 */ TIMESPEC_A_LT_B(&lev->cbs_dline[p], acttime) || |
| /* 2 */ TIMESPEC_A_GT_B(&t3, &t2) ) { |
| |
| /* we modify the deadline ... */ |
| TIMESPEC_ASSIGN(&lev->cbs_dline[p], acttime); |
| ADDUSEC2TIMESPEC(lev->period[p], &lev->cbs_dline[p]); |
| |
| /* and the capacity */ |
| proc_table[p].avail_time = proc_table[p].wcet; |
| |
| } |
| |
| /* and, finally, we reinsert the task in the master level */ |
| job_task_default_model(job, lev->cbs_dline[p]); |
| job_task_def_noexc(job); |
| level_table[ lev->scheduling_level ]-> |
| private_insert(lev->scheduling_level, p, (TASK_MODEL *)&job); |
| |
| } |
| |
| static void HCBS_avail_time_check(HCBS_level_des *lev, PID p) |
| { |
| |
| if (proc_table[p].avail_time < 0) { |
| ADDUSEC2TIMESPEC(lev->period[p], &lev->cbs_dline[p]); |
| proc_table[p].avail_time += proc_table[p].wcet; |
| } |
| |
| } |
| |
| |
| /* this is the periodic reactivation of the task... it is posted only |
| if the task is a periodic task */ |
| static void HCBS_timer_reactivate(void *par) |
| { |
| PID p = (PID) par; |
| HCBS_level_des *lev; |
| |
| lev = (HCBS_level_des *)level_table[proc_table[p].task_level]; |
| |
| if (lev->flag[p] & HCBS_SLEEP && proc_table[p].status == HCBS_IDLE) { |
| proc_table[p].status = SLEEP; |
| return; |
| } |
| |
| if (proc_table[p].status == HCBS_IDLE) { |
| /* the task has finished the current activation and must be |
| reactivated */ |
| HCBS_activation(lev,p,&lev->reactivation_time[p]); |
| |
| event_need_reschedule(); |
| |
| } |
| else if (lev->flag[p] & HCBS_SAVE_ARRIVALS) |
| /* 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... |
| For bandwidth hard reservation, an aperiodic |
| task is forced to generate a reactivate event */ |
| if (!(lev->flag[p] & HCBS_APERIODIC)) { |
| ADDUSEC2TIMESPEC(lev->period[p], &lev->reactivation_time[p]); |
| lev->reactivation_timer[p] = kern_event_post(&lev->reactivation_time[p], |
| HCBS_timer_reactivate, |
| (void *)p); |
| } |
| |
| /* tracer stuff */ |
| trc_logevent(TRC_INTACTIVATION,&p); |
| |
| } |
| |
| /*+ this function is called when a killed or ended task reach the |
| period end +*/ |
| static void HCBS_timer_zombie(void *par) |
| { |
| PID p = (PID) par; |
| |
| /* we finally put the task in the free queue */ |
| proc_table[p].status = FREE; |
| iq_insertfirst(p,&freedesc); |
| |
| } |
| |
| /* The on-line guarantee is enabled only if the appropriate flag is set... */ |
| static int HCBS_public_guarantee(LEVEL l, bandwidth_t *freebandwidth) |
| { |
| HCBS_level_des *lev = (HCBS_level_des *)(level_table[l]); |
| |
| if (*freebandwidth >= lev->U) { |
| *freebandwidth -= lev->U; |
| return 1; |
| } |
| else |
| return 0; |
| } |
| |
| static int HCBS_public_create(LEVEL l, PID p, TASK_MODEL *m) |
| { |
| HCBS_level_des *lev = (HCBS_level_des *)(level_table[l]); |
| SOFT_TASK_MODEL *soft; |
| |
| if (m->pclass != SOFT_PCLASS) return -1; |
| if (m->level != 0 && m->level != l) return -1; |
| soft = (SOFT_TASK_MODEL *)m; |
| if (!(soft->met && soft->period)) return -1; |
| |
| soft = (SOFT_TASK_MODEL *)m; |
| |
| if (lev->flags & HCBS_ENABLE_GUARANTEE) { |
| bandwidth_t b; |
| b = (MAX_BANDWIDTH / soft->period) * soft->met; |
| |
| /* really update lev->U, checking an overflow... */ |
| if (MAX_BANDWIDTH - lev->U > b) |
| lev->U += b; |
| else |
| return -1; |
| } |
| |
| /* Enable wcet check */ |
| proc_table[p].avail_time = soft->met; |
| proc_table[p].wcet = soft->met; |
| proc_table[p].control |= CONTROL_CAP; |
| |
| lev->nact[p] = 0; |
| lev->period[p] = soft->period; |
| NULL_TIMESPEC(&lev->cbs_dline[p]); |
| |
| if (soft->periodicity == APERIODIC) |
| lev->flag[p] = HCBS_APERIODIC; |
| else |
| lev->flag[p] = 0; |
| |
| if (soft->arrivals == SAVE_ARRIVALS) |
| lev->flag[p] |= HCBS_SAVE_ARRIVALS; |
| |
| return 0; /* OK, also if the task cannot be guaranteed... */ |
| } |
| |
| static void HCBS_public_detach(LEVEL l, PID p) |
| { |
| /* the CBS level doesn't introduce any dinamic allocated new field. |
| we have only to decrement the allocated bandwidth */ |
| |
| HCBS_level_des *lev = (HCBS_level_des *)(level_table[l]); |
| |
| if (lev->flags & HCBS_ENABLE_GUARANTEE) { |
| lev->U -= (MAX_BANDWIDTH / lev->period[p]) * proc_table[p].wcet; |
| } |
| } |
| |
| static int HCBS_public_eligible(LEVEL l, PID p) |
| { |
| HCBS_level_des *lev = (HCBS_level_des *)(level_table[l]); |
| JOB_TASK_MODEL job; |
| |
| /* we have to check if the deadline and the wcet are correct... |
| if the CBS level schedules in background with respect to others |
| levels, there can be the case in witch a task is scheduled by |
| schedule_time > CBS_deadline; in this case (not covered in the |
| article because if there is only the standard scheduling policy |
| this never apply) we reassign the deadline */ |
| |
| if ( TIMESPEC_A_LT_B(&lev->cbs_dline[p], &schedule_time) ) { |
| /* we kill the current activation */ |
| level_table[ lev->scheduling_level ]-> |
| private_extract(lev->scheduling_level, p); |
| |
| /* we modify the deadline ... */ |
| TIMESPEC_ASSIGN(&lev->cbs_dline[p], &schedule_time); |
| ADDUSEC2TIMESPEC(lev->period[p], &lev->cbs_dline[p]); |
| |
| /* and the capacity */ |
| proc_table[p].avail_time = proc_table[p].wcet; |
| |
| /* and, finally, we reinsert the task in the master level */ |
| job_task_default_model(job, lev->cbs_dline[p]); |
| job_task_def_noexc(job); |
| level_table[ lev->scheduling_level ]-> |
| private_insert(lev->scheduling_level, p, (TASK_MODEL *)&job); |
| |
| return -1; |
| } |
| |
| return 0; |
| } |
| |
| static void HCBS_public_dispatch(LEVEL l, PID p, int nostop) |
| { |
| HCBS_level_des *lev = (HCBS_level_des *)(level_table[l]); |
| level_table[ lev->scheduling_level ]-> |
| private_dispatch(lev->scheduling_level,p,nostop); |
| } |
| |
| static void HCBS_public_epilogue(LEVEL l, PID p) |
| { |
| HCBS_level_des *lev = (HCBS_level_des *)(level_table[l]); |
| |
| /* check if the wcet is finished... */ |
| if ( proc_table[p].avail_time <= 0) { |
| |
| lev->flag[p] |= HCBS_OVERLOAD; |
| |
| /* we kill the current activation */ |
| level_table[ lev->scheduling_level ]-> |
| private_extract(lev->scheduling_level, p); |
| |
| /* Hard Reservation: The avail_time will be reloaded in the |
| next reactivation event. The task is suspended */ |
| proc_table[p].status = HCBS_IDLE; |
| if (lev->flag[p] & HCBS_APERIODIC) { |
| |
| ADDUSEC2TIMESPEC(lev->period[p], &lev->reactivation_time[p]); |
| lev->reactivation_timer[p] = kern_event_post(&lev->reactivation_time[p], |
| HCBS_timer_reactivate, |
| (void *)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 HCBS_public_activate(LEVEL l, PID p) |
| { |
| HCBS_level_des *lev = (HCBS_level_des *)(level_table[l]); |
| struct timespec t; |
| |
| if (lev->flag[p] & HCBS_SLEEP) { |
| /* disable HCBS_SLEEP flag */ |
| lev->flag[p] &= ~HCBS_SLEEP; |
| if (proc_table[p].status != SLEEP) return; |
| } |
| |
| /* save activation (only if needed... */ |
| if (proc_table[p].status != SLEEP) { |
| if (lev->flag[p] & HCBS_SAVE_ARRIVALS) |
| lev->nact[p]++; |
| return; |
| } |
| |
| kern_gettime(&t); |
| |
| HCBS_activation(lev, p, &t); |
| |
| /* Set the reactivation timer */ |
| if (!(lev->flag[p] & HCBS_APERIODIC)) |
| { |
| /* we cannot use the deadline computed by CBS_activation because |
| the deadline may be != from actual_time + period |
| (if we call the task_activate after a task_sleep, and the |
| deadline was postponed a lot...) */ |
| TIMESPEC_ASSIGN(&lev->reactivation_time[p], &t); |
| ADDUSEC2TIMESPEC(lev->period[p], &lev->reactivation_time[p]); |
| // TIMESPEC_ASSIGN(&lev->reactivation_time[p], &lev->cbs_dline[p]); |
| lev->reactivation_timer[p] = kern_event_post(&lev->reactivation_time[p], |
| HCBS_timer_reactivate, |
| (void *)p); |
| } |
| } |
| |
| static void HCBS_public_unblock(LEVEL l, PID p) |
| { |
| HCBS_level_des *lev = (HCBS_level_des *)(level_table[l]); |
| struct timespec acttime; |
| |
| kern_gettime(&acttime); |
| |
| HCBS_activation(lev,p,&acttime); |
| } |
| |
| static void HCBS_public_block(LEVEL l, PID p) |
| { |
| HCBS_level_des *lev = (HCBS_level_des *)(level_table[l]); |
| |
| /* check if the wcet is finished... */ |
| HCBS_avail_time_check(lev, p); |
| |
| level_table[ lev->scheduling_level ]-> |
| private_extract(lev->scheduling_level,p); |
| } |
| |
| static int HCBS_public_message(LEVEL l, PID p, void *m) |
| { |
| |
| HCBS_command_message *msg; |
| HCBS_level_des *lev = (HCBS_level_des *)(level_table[l]); |
| |
| switch((long)(m)) { |
| |
| /* task_endcycle */ |
| case (long)(NULL): |
| |
| if (!(lev->flag[p] & HCBS_APERIODIC) && lev->flag[p] & HCBS_OVERLOAD) { |
| lev->flag[p] &= ~HCBS_OVERLOAD; |
| lev->nact[p]++; |
| } |
| |
| if (lev->nact[p]) { |
| /* continue!!!! */ |
| lev->nact[p]--; |
| level_table[ lev->scheduling_level ]-> |
| private_epilogue(lev->scheduling_level,p); |
| } else { |
| level_table[ lev->scheduling_level ]-> |
| private_extract(lev->scheduling_level,p); |
| |
| if (lev->flag[p] & HCBS_APERIODIC) |
| proc_table[p].status = SLEEP; |
| else /* the task is soft_periodic */ |
| proc_table[p].status = HCBS_IDLE; |
| } |
| |
| jet_update_endcycle(); /* Update the Jet data... */ |
| trc_logevent(TRC_ENDCYCLE,&exec_shadow); /* tracer stuff */ |
| |
| break; |
| |
| /* task_disable */ |
| case (1): |
| |
| lev->flag[p] |= HCBS_SLEEP; |
| |
| break; |
| |
| /* Set/Get Met/Period */ |
| default: |
| |
| msg = (HCBS_command_message *)(m); |
| |
| switch (msg->command) { |
| case HCBS_SET_PERIOD: |
| lev->U -= (bandwidth_t)(MAX_BANDWIDTH / lev->period[p] |
| * proc_table[p].wcet); |
| lev->period[p] = msg->param; |
| lev->U += (bandwidth_t)(MAX_BANDWIDTH / lev->period[p] |
| * proc_table[p].wcet); |
| break; |
| case HCBS_GET_PERIOD: |
| msg->param = lev->period[p]; |
| break; |
| case HCBS_SET_MET: |
| lev->U -= (bandwidth_t)(MAX_BANDWIDTH / lev->period[p] |
| * proc_table[p].wcet); |
| proc_table[p].wcet = msg->param; |
| lev->U += (bandwidth_t)(MAX_BANDWIDTH / lev->period[p] |
| * proc_table[p].wcet); |
| break; |
| case HCBS_GET_MET: |
| msg->param = proc_table[p].wcet; |
| break; |
| } |
| |
| break; |
| |
| } |
| |
| return 0; |
| |
| } |
| |
| static void HCBS_public_end(LEVEL l, PID p) |
| { |
| HCBS_level_des *lev = (HCBS_level_des *)(level_table[l]); |
| |
| /* check if the wcet is finished... */ |
| HCBS_avail_time_check(lev, p); |
| |
| level_table[ lev->scheduling_level ]-> |
| private_extract(lev->scheduling_level,p); |
| |
| /* free the allocated bandwidth */ |
| lev->U -= (MAX_BANDWIDTH/lev->period[p]) * proc_table[p].wcet; |
| |
| /* we delete the reactivation timer */ |
| if (!(lev->flag[p] & HCBS_APERIODIC)) { |
| 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 = HCBS_ZOMBIE; |
| lev->reactivation_timer[p] = kern_event_post(&lev->cbs_dline[p], |
| HCBS_timer_zombie, |
| (void *)p); |
| } |
| |
| /* Registration functions */ |
| |
| /*+ Registration function: |
| int flags the init flags ... see CBS.h +*/ |
| LEVEL HCBS_register_level(int flags, LEVEL master) |
| { |
| LEVEL l; /* the level that we register */ |
| HCBS_level_des *lev; /* for readableness only */ |
| PID i; /* a counter */ |
| |
| printk("HCBS_register_level\n"); |
| |
| /* request an entry in the level_table */ |
| l = level_alloc_descriptor(sizeof(HCBS_level_des)); |
| |
| lev = (HCBS_level_des *)level_table[l]; |
| |
| printk(" lev=%d\n",(int)lev); |
| |
| /* fill the standard descriptor */ |
| if (flags & HCBS_ENABLE_GUARANTEE) |
| lev->l.public_guarantee = HCBS_public_guarantee; |
| else |
| lev->l.public_guarantee = NULL; |
| lev->l.public_create = HCBS_public_create; |
| lev->l.public_detach = HCBS_public_detach; |
| lev->l.public_end = HCBS_public_end; |
| lev->l.public_eligible = HCBS_public_eligible; |
| lev->l.public_dispatch = HCBS_public_dispatch; |
| lev->l.public_epilogue = HCBS_public_epilogue; |
| lev->l.public_activate = HCBS_public_activate; |
| lev->l.public_unblock = HCBS_public_unblock; |
| lev->l.public_block = HCBS_public_block; |
| lev->l.public_message = HCBS_public_message; |
| |
| /* fill the CBS descriptor part */ |
| for (i=0; i<MAX_PROC; i++) { |
| NULL_TIMESPEC(&lev->cbs_dline[i]); |
| lev->period[i] = 0; |
| NULL_TIMESPEC(&lev->reactivation_time[i]); |
| lev->reactivation_timer[i] = -1; |
| lev->nact[i] = 0; |
| lev->flag[i] = 0; |
| } |
| |
| |
| lev->U = 0; |
| |
| lev->scheduling_level = master; |
| |
| lev->flags = flags; |
| |
| return l; |
| } |
| |
| bandwidth_t HCBS_usedbandwidth(LEVEL l) |
| { |
| HCBS_level_des *lev = (HCBS_level_des *)(level_table[l]); |
| |
| return lev->U; |
| } |
| |
| int HCBS_get_nact(LEVEL l, PID p) |
| { |
| HCBS_level_des *lev = (HCBS_level_des *)(level_table[l]); |
| |
| return lev->nact[p]; |
| } |
| |