diff options
author | Bjoern Brandenburg <bbb@mpi-sws.org> | 2015-08-09 07:18:55 -0400 |
---|---|---|
committer | Bjoern Brandenburg <bbb@mpi-sws.org> | 2015-08-09 07:20:34 -0400 |
commit | 47efe5234212e0f72369a6964dfd84d4e9968a11 (patch) | |
tree | 2c489ea0b878363068cfcb0ecb33054b79d7d2a4 | |
parent | 4410877f28d1a20b5c98dd153de78c8342ac76f3 (diff) |
Add PSN-EDF scheduler plugin
-rw-r--r-- | litmus/Makefile | 4 | ||||
-rw-r--r-- | litmus/sched_psn_edf.c | 688 |
2 files changed, 691 insertions, 1 deletions
diff --git a/litmus/Makefile b/litmus/Makefile index c85abc7389c5..4e53c4f69744 100644 --- a/litmus/Makefile +++ b/litmus/Makefile | |||
@@ -18,7 +18,9 @@ obj-y = sched_plugin.o litmus.o \ | |||
18 | bheap.o \ | 18 | bheap.o \ |
19 | binheap.o \ | 19 | binheap.o \ |
20 | ctrldev.o \ | 20 | ctrldev.o \ |
21 | uncachedev.o | 21 | uncachedev.o \ |
22 | sched_psn_edf.o | ||
23 | |||
22 | 24 | ||
23 | obj-$(CONFIG_FEATHER_TRACE) += ft_event.o ftdev.o | 25 | obj-$(CONFIG_FEATHER_TRACE) += ft_event.o ftdev.o |
24 | obj-$(CONFIG_SCHED_TASK_TRACE) += sched_task_trace.o | 26 | obj-$(CONFIG_SCHED_TASK_TRACE) += sched_task_trace.o |
diff --git a/litmus/sched_psn_edf.c b/litmus/sched_psn_edf.c new file mode 100644 index 000000000000..2549a3fc28b9 --- /dev/null +++ b/litmus/sched_psn_edf.c | |||
@@ -0,0 +1,688 @@ | |||
1 | /* | ||
2 | * kernel/sched_psn_edf.c | ||
3 | * | ||
4 | * Implementation of the PSN-EDF scheduler plugin. | ||
5 | * Based on kern/sched_part_edf.c and kern/sched_gsn_edf.c. | ||
6 | * | ||
7 | * Suspensions and non-preemptable sections are supported. | ||
8 | * Priority inheritance is not supported. | ||
9 | */ | ||
10 | |||
11 | #include <linux/percpu.h> | ||
12 | #include <linux/sched.h> | ||
13 | #include <linux/list.h> | ||
14 | #include <linux/spinlock.h> | ||
15 | #include <linux/module.h> | ||
16 | |||
17 | #include <litmus/litmus.h> | ||
18 | #include <litmus/jobs.h> | ||
19 | #include <litmus/preempt.h> | ||
20 | #include <litmus/budget.h> | ||
21 | #include <litmus/sched_plugin.h> | ||
22 | #include <litmus/edf_common.h> | ||
23 | #include <litmus/sched_trace.h> | ||
24 | #include <litmus/trace.h> | ||
25 | |||
26 | /* to set up domain/cpu mappings */ | ||
27 | #include <litmus/litmus_proc.h> | ||
28 | |||
29 | typedef struct { | ||
30 | rt_domain_t domain; | ||
31 | int cpu; | ||
32 | struct task_struct* scheduled; /* only RT tasks */ | ||
33 | /* | ||
34 | * scheduling lock slock | ||
35 | * protects the domain and serializes scheduling decisions | ||
36 | */ | ||
37 | #define slock domain.ready_lock | ||
38 | |||
39 | } psnedf_domain_t; | ||
40 | |||
41 | DEFINE_PER_CPU(psnedf_domain_t, psnedf_domains); | ||
42 | |||
43 | #define local_edf (&(this_cpu_ptr(&psnedf_domains)->domain)) | ||
44 | #define local_pedf (this_cpu_ptr(&psnedf_domains)) | ||
45 | #define remote_edf(cpu) (&per_cpu(psnedf_domains, cpu).domain) | ||
46 | #define remote_pedf(cpu) (&per_cpu(psnedf_domains, cpu)) | ||
47 | #define task_edf(task) remote_edf(get_partition(task)) | ||
48 | #define task_pedf(task) remote_pedf(get_partition(task)) | ||
49 | |||
50 | |||
51 | static void psnedf_domain_init(psnedf_domain_t* pedf, | ||
52 | check_resched_needed_t check, | ||
53 | release_jobs_t release, | ||
54 | int cpu) | ||
55 | { | ||
56 | edf_domain_init(&pedf->domain, check, release); | ||
57 | pedf->cpu = cpu; | ||
58 | pedf->scheduled = NULL; | ||
59 | } | ||
60 | |||
61 | static void requeue(struct task_struct* t, rt_domain_t *edf) | ||
62 | { | ||
63 | if (t->state != TASK_RUNNING) | ||
64 | TRACE_TASK(t, "requeue: !TASK_RUNNING\n"); | ||
65 | |||
66 | tsk_rt(t)->completed = 0; | ||
67 | if (is_early_releasing(t) || is_released(t, litmus_clock())) | ||
68 | __add_ready(edf, t); | ||
69 | else | ||
70 | add_release(edf, t); /* it has got to wait */ | ||
71 | } | ||
72 | |||
73 | /* we assume the lock is being held */ | ||
74 | static void preempt(psnedf_domain_t *pedf) | ||
75 | { | ||
76 | preempt_if_preemptable(pedf->scheduled, pedf->cpu); | ||
77 | } | ||
78 | |||
79 | #ifdef CONFIG_LITMUS_LOCKING | ||
80 | |||
81 | static void boost_priority(struct task_struct* t) | ||
82 | { | ||
83 | unsigned long flags; | ||
84 | psnedf_domain_t* pedf = task_pedf(t); | ||
85 | lt_t now; | ||
86 | |||
87 | raw_spin_lock_irqsave(&pedf->slock, flags); | ||
88 | now = litmus_clock(); | ||
89 | |||
90 | TRACE_TASK(t, "priority boosted at %llu\n", now); | ||
91 | |||
92 | tsk_rt(t)->priority_boosted = 1; | ||
93 | tsk_rt(t)->boost_start_time = now; | ||
94 | |||
95 | if (pedf->scheduled != t) { | ||
96 | /* holder may be queued: first stop queue changes */ | ||
97 | raw_spin_lock(&pedf->domain.release_lock); | ||
98 | if (is_queued(t) && | ||
99 | /* If it is queued, then we need to re-order. */ | ||
100 | bheap_decrease(edf_ready_order, tsk_rt(t)->heap_node) && | ||
101 | /* If we bubbled to the top, then we need to check for preemptions. */ | ||
102 | edf_preemption_needed(&pedf->domain, pedf->scheduled)) | ||
103 | preempt(pedf); | ||
104 | raw_spin_unlock(&pedf->domain.release_lock); | ||
105 | } /* else: nothing to do since the job is not queued while scheduled */ | ||
106 | |||
107 | raw_spin_unlock_irqrestore(&pedf->slock, flags); | ||
108 | } | ||
109 | |||
110 | static void unboost_priority(struct task_struct* t) | ||
111 | { | ||
112 | unsigned long flags; | ||
113 | psnedf_domain_t* pedf = task_pedf(t); | ||
114 | lt_t now; | ||
115 | |||
116 | raw_spin_lock_irqsave(&pedf->slock, flags); | ||
117 | now = litmus_clock(); | ||
118 | |||
119 | /* Assumption: this only happens when the job is scheduled. | ||
120 | * Exception: If t transitioned to non-real-time mode, we no longer | ||
121 | * care about it. */ | ||
122 | BUG_ON(pedf->scheduled != t && is_realtime(t)); | ||
123 | |||
124 | TRACE_TASK(t, "priority restored at %llu\n", now); | ||
125 | |||
126 | tsk_rt(t)->priority_boosted = 0; | ||
127 | tsk_rt(t)->boost_start_time = 0; | ||
128 | |||
129 | /* check if this changes anything */ | ||
130 | if (edf_preemption_needed(&pedf->domain, pedf->scheduled)) | ||
131 | preempt(pedf); | ||
132 | |||
133 | raw_spin_unlock_irqrestore(&pedf->slock, flags); | ||
134 | } | ||
135 | |||
136 | #endif | ||
137 | |||
138 | static int psnedf_preempt_check(psnedf_domain_t *pedf) | ||
139 | { | ||
140 | if (edf_preemption_needed(&pedf->domain, pedf->scheduled)) { | ||
141 | preempt(pedf); | ||
142 | return 1; | ||
143 | } else | ||
144 | return 0; | ||
145 | } | ||
146 | |||
147 | /* This check is trivial in partioned systems as we only have to consider | ||
148 | * the CPU of the partition. | ||
149 | */ | ||
150 | static int psnedf_check_resched(rt_domain_t *edf) | ||
151 | { | ||
152 | psnedf_domain_t *pedf = container_of(edf, psnedf_domain_t, domain); | ||
153 | |||
154 | /* because this is a callback from rt_domain_t we already hold | ||
155 | * the necessary lock for the ready queue | ||
156 | */ | ||
157 | return psnedf_preempt_check(pedf); | ||
158 | } | ||
159 | |||
160 | static void job_completion(struct task_struct* t, int forced) | ||
161 | { | ||
162 | sched_trace_task_completion(t, forced); | ||
163 | TRACE_TASK(t, "job_completion(forced=%d).\n", forced); | ||
164 | |||
165 | tsk_rt(t)->completed = 0; | ||
166 | prepare_for_next_period(t); | ||
167 | } | ||
168 | |||
169 | static struct task_struct* psnedf_schedule(struct task_struct * prev) | ||
170 | { | ||
171 | psnedf_domain_t* pedf = local_pedf; | ||
172 | rt_domain_t* edf = &pedf->domain; | ||
173 | struct task_struct* next; | ||
174 | |||
175 | int out_of_time, sleep, preempt, | ||
176 | np, exists, blocks, resched; | ||
177 | |||
178 | raw_spin_lock(&pedf->slock); | ||
179 | |||
180 | /* sanity checking | ||
181 | * differently from gedf, when a task exits (dead) | ||
182 | * pedf->schedule may be null and prev _is_ realtime | ||
183 | */ | ||
184 | BUG_ON(pedf->scheduled && pedf->scheduled != prev); | ||
185 | BUG_ON(pedf->scheduled && !is_realtime(prev)); | ||
186 | |||
187 | /* (0) Determine state */ | ||
188 | exists = pedf->scheduled != NULL; | ||
189 | blocks = exists && !is_current_running(); | ||
190 | out_of_time = exists && budget_enforced(pedf->scheduled) | ||
191 | && budget_exhausted(pedf->scheduled); | ||
192 | np = exists && is_np(pedf->scheduled); | ||
193 | sleep = exists && is_completed(pedf->scheduled); | ||
194 | preempt = edf_preemption_needed(edf, prev); | ||
195 | |||
196 | /* If we need to preempt do so. | ||
197 | * The following checks set resched to 1 in case of special | ||
198 | * circumstances. | ||
199 | */ | ||
200 | resched = preempt; | ||
201 | |||
202 | /* If a task blocks we have no choice but to reschedule. | ||
203 | */ | ||
204 | if (blocks) | ||
205 | resched = 1; | ||
206 | |||
207 | /* Request a sys_exit_np() call if we would like to preempt but cannot. | ||
208 | * Multiple calls to request_exit_np() don't hurt. | ||
209 | */ | ||
210 | if (np && (out_of_time || preempt || sleep)) | ||
211 | request_exit_np(pedf->scheduled); | ||
212 | |||
213 | /* Any task that is preemptable and either exhausts its execution | ||
214 | * budget or wants to sleep completes. We may have to reschedule after | ||
215 | * this. | ||
216 | */ | ||
217 | if (!np && (out_of_time || sleep)) { | ||
218 | job_completion(pedf->scheduled, !sleep); | ||
219 | resched = 1; | ||
220 | } | ||
221 | |||
222 | /* The final scheduling decision. Do we need to switch for some reason? | ||
223 | * Switch if we are in RT mode and have no task or if we need to | ||
224 | * resched. | ||
225 | */ | ||
226 | next = NULL; | ||
227 | if ((!np || blocks) && (resched || !exists)) { | ||
228 | /* When preempting a task that does not block, then | ||
229 | * re-insert it into either the ready queue or the | ||
230 | * release queue (if it completed). requeue() picks | ||
231 | * the appropriate queue. | ||
232 | */ | ||
233 | if (pedf->scheduled && !blocks) | ||
234 | requeue(pedf->scheduled, edf); | ||
235 | next = __take_ready(edf); | ||
236 | } else | ||
237 | /* Only override Linux scheduler if we have a real-time task | ||
238 | * scheduled that needs to continue. | ||
239 | */ | ||
240 | if (exists) | ||
241 | next = prev; | ||
242 | |||
243 | if (next) { | ||
244 | TRACE_TASK(next, "scheduled at %llu\n", litmus_clock()); | ||
245 | } else { | ||
246 | TRACE("becoming idle at %llu\n", litmus_clock()); | ||
247 | } | ||
248 | |||
249 | pedf->scheduled = next; | ||
250 | sched_state_task_picked(); | ||
251 | raw_spin_unlock(&pedf->slock); | ||
252 | |||
253 | return next; | ||
254 | } | ||
255 | |||
256 | |||
257 | /* Prepare a task for running in RT mode | ||
258 | */ | ||
259 | static void psnedf_task_new(struct task_struct * t, int on_rq, int is_scheduled) | ||
260 | { | ||
261 | rt_domain_t* edf = task_edf(t); | ||
262 | psnedf_domain_t* pedf = task_pedf(t); | ||
263 | unsigned long flags; | ||
264 | |||
265 | TRACE_TASK(t, "psn edf: task new, cpu = %d\n", | ||
266 | t->rt_param.task_params.cpu); | ||
267 | |||
268 | /* setup job parameters */ | ||
269 | release_at(t, litmus_clock()); | ||
270 | |||
271 | /* The task should be running in the queue, otherwise signal | ||
272 | * code will try to wake it up with fatal consequences. | ||
273 | */ | ||
274 | raw_spin_lock_irqsave(&pedf->slock, flags); | ||
275 | if (is_scheduled) { | ||
276 | /* there shouldn't be anything else scheduled at the time */ | ||
277 | BUG_ON(pedf->scheduled); | ||
278 | pedf->scheduled = t; | ||
279 | } else { | ||
280 | /* !is_scheduled means it is not scheduled right now, but it | ||
281 | * does not mean that it is suspended. If it is not suspended, | ||
282 | * it still needs to be requeued. If it is suspended, there is | ||
283 | * nothing that we need to do as it will be handled by the | ||
284 | * wake_up() handler. */ | ||
285 | if (on_rq) { | ||
286 | requeue(t, edf); | ||
287 | /* maybe we have to reschedule */ | ||
288 | psnedf_preempt_check(pedf); | ||
289 | } | ||
290 | } | ||
291 | raw_spin_unlock_irqrestore(&pedf->slock, flags); | ||
292 | } | ||
293 | |||
294 | static void psnedf_task_wake_up(struct task_struct *task) | ||
295 | { | ||
296 | unsigned long flags; | ||
297 | psnedf_domain_t* pedf = task_pedf(task); | ||
298 | rt_domain_t* edf = task_edf(task); | ||
299 | lt_t now; | ||
300 | |||
301 | TRACE_TASK(task, "wake_up at %llu\n", litmus_clock()); | ||
302 | raw_spin_lock_irqsave(&pedf->slock, flags); | ||
303 | BUG_ON(is_queued(task)); | ||
304 | now = litmus_clock(); | ||
305 | if (is_sporadic(task) && is_tardy(task, now) | ||
306 | #ifdef CONFIG_LITMUS_LOCKING | ||
307 | /* We need to take suspensions because of semaphores into | ||
308 | * account! If a job resumes after being suspended due to acquiring | ||
309 | * a semaphore, it should never be treated as a new job release. | ||
310 | */ | ||
311 | && !is_priority_boosted(task) | ||
312 | #endif | ||
313 | ) { | ||
314 | /* new sporadic release */ | ||
315 | release_at(task, now); | ||
316 | sched_trace_task_release(task); | ||
317 | } | ||
318 | |||
319 | /* Only add to ready queue if it is not the currently-scheduled | ||
320 | * task. This could be the case if a task was woken up concurrently | ||
321 | * on a remote CPU before the executing CPU got around to actually | ||
322 | * de-scheduling the task, i.e., wake_up() raced with schedule() | ||
323 | * and won. | ||
324 | */ | ||
325 | if (pedf->scheduled != task) { | ||
326 | requeue(task, edf); | ||
327 | psnedf_preempt_check(pedf); | ||
328 | } | ||
329 | |||
330 | raw_spin_unlock_irqrestore(&pedf->slock, flags); | ||
331 | TRACE_TASK(task, "wake up done\n"); | ||
332 | } | ||
333 | |||
334 | static void psnedf_task_block(struct task_struct *t) | ||
335 | { | ||
336 | /* only running tasks can block, thus t is in no queue */ | ||
337 | TRACE_TASK(t, "block at %llu, state=%d\n", litmus_clock(), t->state); | ||
338 | |||
339 | BUG_ON(!is_realtime(t)); | ||
340 | BUG_ON(is_queued(t)); | ||
341 | } | ||
342 | |||
343 | static void psnedf_task_exit(struct task_struct * t) | ||
344 | { | ||
345 | unsigned long flags; | ||
346 | psnedf_domain_t* pedf = task_pedf(t); | ||
347 | rt_domain_t* edf; | ||
348 | |||
349 | raw_spin_lock_irqsave(&pedf->slock, flags); | ||
350 | if (is_queued(t)) { | ||
351 | /* dequeue */ | ||
352 | edf = task_edf(t); | ||
353 | remove(edf, t); | ||
354 | } | ||
355 | if (pedf->scheduled == t) | ||
356 | pedf->scheduled = NULL; | ||
357 | |||
358 | TRACE_TASK(t, "RIP, now reschedule\n"); | ||
359 | |||
360 | preempt(pedf); | ||
361 | raw_spin_unlock_irqrestore(&pedf->slock, flags); | ||
362 | } | ||
363 | |||
364 | #ifdef CONFIG_LITMUS_LOCKING | ||
365 | |||
366 | #include <litmus/fdso.h> | ||
367 | #include <litmus/srp.h> | ||
368 | |||
369 | /* ******************** SRP support ************************ */ | ||
370 | |||
371 | static unsigned int psnedf_get_srp_prio(struct task_struct* t) | ||
372 | { | ||
373 | return get_rt_relative_deadline(t); | ||
374 | } | ||
375 | |||
376 | /* ******************** FMLP support ********************** */ | ||
377 | |||
378 | /* struct for semaphore with priority inheritance */ | ||
379 | struct fmlp_semaphore { | ||
380 | struct litmus_lock litmus_lock; | ||
381 | |||
382 | /* current resource holder */ | ||
383 | struct task_struct *owner; | ||
384 | |||
385 | /* FIFO queue of waiting tasks */ | ||
386 | wait_queue_head_t wait; | ||
387 | }; | ||
388 | |||
389 | static inline struct fmlp_semaphore* fmlp_from_lock(struct litmus_lock* lock) | ||
390 | { | ||
391 | return container_of(lock, struct fmlp_semaphore, litmus_lock); | ||
392 | } | ||
393 | int psnedf_fmlp_lock(struct litmus_lock* l) | ||
394 | { | ||
395 | struct task_struct* t = current; | ||
396 | struct fmlp_semaphore *sem = fmlp_from_lock(l); | ||
397 | wait_queue_t wait; | ||
398 | unsigned long flags; | ||
399 | |||
400 | if (!is_realtime(t)) | ||
401 | return -EPERM; | ||
402 | |||
403 | /* prevent nested lock acquisition --- not supported by FMLP */ | ||
404 | if (tsk_rt(t)->num_locks_held || | ||
405 | tsk_rt(t)->num_local_locks_held) | ||
406 | return -EBUSY; | ||
407 | |||
408 | spin_lock_irqsave(&sem->wait.lock, flags); | ||
409 | |||
410 | if (sem->owner) { | ||
411 | /* resource is not free => must suspend and wait */ | ||
412 | |||
413 | init_waitqueue_entry(&wait, t); | ||
414 | |||
415 | /* FIXME: interruptible would be nice some day */ | ||
416 | set_task_state(t, TASK_UNINTERRUPTIBLE); | ||
417 | |||
418 | __add_wait_queue_tail_exclusive(&sem->wait, &wait); | ||
419 | |||
420 | TS_LOCK_SUSPEND; | ||
421 | |||
422 | /* release lock before sleeping */ | ||
423 | spin_unlock_irqrestore(&sem->wait.lock, flags); | ||
424 | |||
425 | /* We depend on the FIFO order. Thus, we don't need to recheck | ||
426 | * when we wake up; we are guaranteed to have the lock since | ||
427 | * there is only one wake up per release. | ||
428 | */ | ||
429 | |||
430 | schedule(); | ||
431 | |||
432 | TS_LOCK_RESUME; | ||
433 | |||
434 | /* Since we hold the lock, no other task will change | ||
435 | * ->owner. We can thus check it without acquiring the spin | ||
436 | * lock. */ | ||
437 | BUG_ON(sem->owner != t); | ||
438 | } else { | ||
439 | /* it's ours now */ | ||
440 | sem->owner = t; | ||
441 | |||
442 | /* mark the task as priority-boosted. */ | ||
443 | boost_priority(t); | ||
444 | |||
445 | spin_unlock_irqrestore(&sem->wait.lock, flags); | ||
446 | } | ||
447 | |||
448 | tsk_rt(t)->num_locks_held++; | ||
449 | |||
450 | return 0; | ||
451 | } | ||
452 | |||
453 | int psnedf_fmlp_unlock(struct litmus_lock* l) | ||
454 | { | ||
455 | struct task_struct *t = current, *next; | ||
456 | struct fmlp_semaphore *sem = fmlp_from_lock(l); | ||
457 | unsigned long flags; | ||
458 | int err = 0; | ||
459 | |||
460 | spin_lock_irqsave(&sem->wait.lock, flags); | ||
461 | |||
462 | if (sem->owner != t) { | ||
463 | err = -EINVAL; | ||
464 | goto out; | ||
465 | } | ||
466 | |||
467 | tsk_rt(t)->num_locks_held--; | ||
468 | |||
469 | /* we lose the benefit of priority boosting */ | ||
470 | |||
471 | unboost_priority(t); | ||
472 | |||
473 | /* check if there are jobs waiting for this resource */ | ||
474 | next = __waitqueue_remove_first(&sem->wait); | ||
475 | if (next) { | ||
476 | /* boost next job */ | ||
477 | boost_priority(next); | ||
478 | |||
479 | /* next becomes the resouce holder */ | ||
480 | sem->owner = next; | ||
481 | |||
482 | /* wake up next */ | ||
483 | wake_up_process(next); | ||
484 | } else | ||
485 | /* resource becomes available */ | ||
486 | sem->owner = NULL; | ||
487 | |||
488 | out: | ||
489 | spin_unlock_irqrestore(&sem->wait.lock, flags); | ||
490 | return err; | ||
491 | } | ||
492 | |||
493 | int psnedf_fmlp_close(struct litmus_lock* l) | ||
494 | { | ||
495 | struct task_struct *t = current; | ||
496 | struct fmlp_semaphore *sem = fmlp_from_lock(l); | ||
497 | unsigned long flags; | ||
498 | |||
499 | int owner; | ||
500 | |||
501 | spin_lock_irqsave(&sem->wait.lock, flags); | ||
502 | |||
503 | owner = sem->owner == t; | ||
504 | |||
505 | spin_unlock_irqrestore(&sem->wait.lock, flags); | ||
506 | |||
507 | if (owner) | ||
508 | psnedf_fmlp_unlock(l); | ||
509 | |||
510 | return 0; | ||
511 | } | ||
512 | |||
513 | void psnedf_fmlp_free(struct litmus_lock* lock) | ||
514 | { | ||
515 | kfree(fmlp_from_lock(lock)); | ||
516 | } | ||
517 | |||
518 | static struct litmus_lock_ops psnedf_fmlp_lock_ops = { | ||
519 | .close = psnedf_fmlp_close, | ||
520 | .lock = psnedf_fmlp_lock, | ||
521 | .unlock = psnedf_fmlp_unlock, | ||
522 | .deallocate = psnedf_fmlp_free, | ||
523 | }; | ||
524 | |||
525 | static struct litmus_lock* psnedf_new_fmlp(void) | ||
526 | { | ||
527 | struct fmlp_semaphore* sem; | ||
528 | |||
529 | sem = kmalloc(sizeof(*sem), GFP_KERNEL); | ||
530 | if (!sem) | ||
531 | return NULL; | ||
532 | |||
533 | sem->owner = NULL; | ||
534 | init_waitqueue_head(&sem->wait); | ||
535 | sem->litmus_lock.ops = &psnedf_fmlp_lock_ops; | ||
536 | |||
537 | return &sem->litmus_lock; | ||
538 | } | ||
539 | |||
540 | /* **** lock constructor **** */ | ||
541 | |||
542 | |||
543 | static long psnedf_allocate_lock(struct litmus_lock **lock, int type, | ||
544 | void* __user unused) | ||
545 | { | ||
546 | int err = -ENXIO; | ||
547 | struct srp_semaphore* srp; | ||
548 | |||
549 | /* PSN-EDF currently supports the SRP for local resources and the FMLP | ||
550 | * for global resources. */ | ||
551 | switch (type) { | ||
552 | case FMLP_SEM: | ||
553 | /* Flexible Multiprocessor Locking Protocol */ | ||
554 | *lock = psnedf_new_fmlp(); | ||
555 | if (*lock) | ||
556 | err = 0; | ||
557 | else | ||
558 | err = -ENOMEM; | ||
559 | break; | ||
560 | |||
561 | case SRP_SEM: | ||
562 | /* Baker's Stack Resource Policy */ | ||
563 | srp = allocate_srp_semaphore(); | ||
564 | if (srp) { | ||
565 | *lock = &srp->litmus_lock; | ||
566 | err = 0; | ||
567 | } else | ||
568 | err = -ENOMEM; | ||
569 | break; | ||
570 | }; | ||
571 | |||
572 | return err; | ||
573 | } | ||
574 | |||
575 | #endif | ||
576 | |||
577 | static struct domain_proc_info psnedf_domain_proc_info; | ||
578 | static long psnedf_get_domain_proc_info(struct domain_proc_info **ret) | ||
579 | { | ||
580 | *ret = &psnedf_domain_proc_info; | ||
581 | return 0; | ||
582 | } | ||
583 | |||
584 | static void psnedf_setup_domain_proc(void) | ||
585 | { | ||
586 | int i, cpu; | ||
587 | int release_master = | ||
588 | #ifdef CONFIG_RELEASE_MASTER | ||
589 | atomic_read(&release_master_cpu); | ||
590 | #else | ||
591 | NO_CPU; | ||
592 | #endif | ||
593 | int num_rt_cpus = num_online_cpus() - (release_master != NO_CPU); | ||
594 | struct cd_mapping *cpu_map, *domain_map; | ||
595 | |||
596 | memset(&psnedf_domain_proc_info, sizeof(psnedf_domain_proc_info), 0); | ||
597 | init_domain_proc_info(&psnedf_domain_proc_info, num_rt_cpus, num_rt_cpus); | ||
598 | psnedf_domain_proc_info.num_cpus = num_rt_cpus; | ||
599 | psnedf_domain_proc_info.num_domains = num_rt_cpus; | ||
600 | |||
601 | for (cpu = 0, i = 0; cpu < num_online_cpus(); ++cpu) { | ||
602 | if (cpu == release_master) | ||
603 | continue; | ||
604 | cpu_map = &psnedf_domain_proc_info.cpu_to_domains[i]; | ||
605 | domain_map = &psnedf_domain_proc_info.domain_to_cpus[i]; | ||
606 | |||
607 | cpu_map->id = cpu; | ||
608 | domain_map->id = i; /* enumerate w/o counting the release master */ | ||
609 | cpumask_set_cpu(i, cpu_map->mask); | ||
610 | cpumask_set_cpu(cpu, domain_map->mask); | ||
611 | ++i; | ||
612 | } | ||
613 | } | ||
614 | |||
615 | static long psnedf_activate_plugin(void) | ||
616 | { | ||
617 | #ifdef CONFIG_RELEASE_MASTER | ||
618 | int cpu; | ||
619 | |||
620 | for_each_online_cpu(cpu) { | ||
621 | remote_edf(cpu)->release_master = atomic_read(&release_master_cpu); | ||
622 | } | ||
623 | #endif | ||
624 | |||
625 | #ifdef CONFIG_LITMUS_LOCKING | ||
626 | get_srp_prio = psnedf_get_srp_prio; | ||
627 | #endif | ||
628 | |||
629 | psnedf_setup_domain_proc(); | ||
630 | |||
631 | return 0; | ||
632 | } | ||
633 | |||
634 | static long psnedf_deactivate_plugin(void) | ||
635 | { | ||
636 | destroy_domain_proc_info(&psnedf_domain_proc_info); | ||
637 | return 0; | ||
638 | } | ||
639 | |||
640 | static long psnedf_admit_task(struct task_struct* tsk) | ||
641 | { | ||
642 | if (task_cpu(tsk) == tsk->rt_param.task_params.cpu | ||
643 | #ifdef CONFIG_RELEASE_MASTER | ||
644 | /* don't allow tasks on release master CPU */ | ||
645 | && task_cpu(tsk) != remote_edf(task_cpu(tsk))->release_master | ||
646 | #endif | ||
647 | ) | ||
648 | return 0; | ||
649 | else | ||
650 | return -EINVAL; | ||
651 | } | ||
652 | |||
653 | /* Plugin object */ | ||
654 | static struct sched_plugin psn_edf_plugin __cacheline_aligned_in_smp = { | ||
655 | .plugin_name = "PSN-EDF", | ||
656 | .task_new = psnedf_task_new, | ||
657 | .complete_job = complete_job, | ||
658 | .task_exit = psnedf_task_exit, | ||
659 | .schedule = psnedf_schedule, | ||
660 | .task_wake_up = psnedf_task_wake_up, | ||
661 | .task_block = psnedf_task_block, | ||
662 | .admit_task = psnedf_admit_task, | ||
663 | .activate_plugin = psnedf_activate_plugin, | ||
664 | .deactivate_plugin = psnedf_deactivate_plugin, | ||
665 | .get_domain_proc_info = psnedf_get_domain_proc_info, | ||
666 | #ifdef CONFIG_LITMUS_LOCKING | ||
667 | .allocate_lock = psnedf_allocate_lock, | ||
668 | #endif | ||
669 | }; | ||
670 | |||
671 | |||
672 | static int __init init_psn_edf(void) | ||
673 | { | ||
674 | int i; | ||
675 | |||
676 | /* We do not really want to support cpu hotplug, do we? ;) | ||
677 | * However, if we are so crazy to do so, | ||
678 | * we cannot use num_online_cpu() | ||
679 | */ | ||
680 | for (i = 0; i < num_online_cpus(); i++) { | ||
681 | psnedf_domain_init(remote_pedf(i), | ||
682 | psnedf_check_resched, | ||
683 | NULL, i); | ||
684 | } | ||
685 | return register_sched_plugin(&psn_edf_plugin); | ||
686 | } | ||
687 | |||
688 | module_init(init_psn_edf); | ||