| 20,11 → 20,11 |
|---|
| |
| /** |
| ------------ |
| CVS : $Id: rm.c,v 1.4 2003-01-07 17:07:50 pj Exp $ |
| CVS : $Id: rm.c,v 1.5 2003-05-05 07:31:44 pj Exp $ |
| |
| File: $File$ |
| Revision: $Revision: 1.4 $ |
| Last update: $Date: 2003-01-07 17:07:50 $ |
| Revision: $Revision: 1.5 $ |
| Last update: $Date: 2003-05-05 07:31:44 $ |
| ------------ |
| |
| This file contains the scheduling module RM (Rate Monotonic) |
| 168,18 → 168,12 |
|---|
| { |
| RM_level_des *lev = (RM_level_des *)(level_table[l]); |
| |
| if (lev->flags & RM_FAILED_GUARANTEE) { |
| *freebandwidth = 0; |
| return 0; |
| if (*freebandwidth >= lev->U) { |
| *freebandwidth -= lev->U; |
| return 1; |
| } |
| else |
| if (*freebandwidth >= lev->U) { |
| *freebandwidth -= lev->U; |
| return 1; |
| } |
| else |
| return 0; |
| |
| return 0; |
| } |
| |
| static int RM_public_create(LEVEL l, PID p, TASK_MODEL *m) |
| 192,6 → 186,19 |
|---|
| if (m->level != 0 && m->level != l) return -1; |
| h = (HARD_TASK_MODEL *)m; |
| if (!h->wcet || !h->mit) return -1; |
| |
| /* update the bandwidth... */ |
| if (lev->flags & RM_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 |
| return -1; |
| } |
| |
| /* now we know that m is a valid model */ |
| |
| *iq_query_priority(p, &lev->ready) = lev->period[p] = h->mit; |
| 209,30 → 216,6 |
|---|
| proc_table[p].control |= CONTROL_CAP; |
| } |
| |
| /* update the bandwidth... */ |
| if (lev->flags & RM_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 |
| RM_task_create the task_create will call level_guarantee that return |
| -1... return -1 in RM_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 |= RM_FAILED_GUARANTEE; |
| } |
| |
| return 0; /* OK, also if the task cannot be guaranteed... */ |
| } |
| |
| 244,10 → 227,9 |
|---|
| |
| RM_level_des *lev = (RM_level_des *)(level_table[l]); |
| |
| if (lev->flags & RM_FAILED_GUARANTEE) |
| lev->flags &= ~RM_FAILED_GUARANTEE; |
| else |
| if (lev->flags & RM_ENABLE_GUARANTEE) { |
| lev->U -= (MAX_BANDWIDTH / lev->period[p]) * proc_table[p].wcet; |
| } |
| } |
| |
| static void RM_public_dispatch(LEVEL l, PID p, int nostop) |
| 488,7 → 470,7 |
|---|
| } |
| |
| iq_init(&lev->ready, &freedesc, 0); |
| lev->flags = flags & 0x07; |
| lev->flags = flags; |
| lev->U = 0; |
| |
| return l; |