blob: 6892ed7d644b48edb92b505f07669bd8eb5ba4bb [file] [log] [blame]
Ingo Molnarbb44e5d2007-07-09 18:51:58 +02001/*
2 * Real-Time Scheduling Class (mapped to the SCHED_FIFO and SCHED_RR
3 * policies)
4 */
5
Peter Zijlstra029632f2011-10-25 10:00:11 +02006#include "sched.h"
7
8#include <linux/slab.h>
9
Clark Williamsce0dbbb2013-02-07 09:47:04 -060010int sched_rr_timeslice = RR_TIMESLICE;
11
Peter Zijlstra029632f2011-10-25 10:00:11 +020012static int do_sched_rt_period_timer(struct rt_bandwidth *rt_b, int overrun);
13
14struct rt_bandwidth def_rt_bandwidth;
15
16static enum hrtimer_restart sched_rt_period_timer(struct hrtimer *timer)
17{
18 struct rt_bandwidth *rt_b =
19 container_of(timer, struct rt_bandwidth, rt_period_timer);
20 ktime_t now;
21 int overrun;
22 int idle = 0;
23
24 for (;;) {
25 now = hrtimer_cb_get_time(timer);
26 overrun = hrtimer_forward(timer, now, rt_b->rt_period);
27
28 if (!overrun)
29 break;
30
31 idle = do_sched_rt_period_timer(rt_b, overrun);
32 }
33
34 return idle ? HRTIMER_NORESTART : HRTIMER_RESTART;
35}
36
37void init_rt_bandwidth(struct rt_bandwidth *rt_b, u64 period, u64 runtime)
38{
39 rt_b->rt_period = ns_to_ktime(period);
40 rt_b->rt_runtime = runtime;
41
42 raw_spin_lock_init(&rt_b->rt_runtime_lock);
43
44 hrtimer_init(&rt_b->rt_period_timer,
45 CLOCK_MONOTONIC, HRTIMER_MODE_REL);
46 rt_b->rt_period_timer.function = sched_rt_period_timer;
47}
48
49static void start_rt_bandwidth(struct rt_bandwidth *rt_b)
50{
51 if (!rt_bandwidth_enabled() || rt_b->rt_runtime == RUNTIME_INF)
52 return;
53
54 if (hrtimer_active(&rt_b->rt_period_timer))
55 return;
56
57 raw_spin_lock(&rt_b->rt_runtime_lock);
58 start_bandwidth_timer(&rt_b->rt_period_timer, rt_b->rt_period);
59 raw_spin_unlock(&rt_b->rt_runtime_lock);
60}
61
62void init_rt_rq(struct rt_rq *rt_rq, struct rq *rq)
63{
64 struct rt_prio_array *array;
65 int i;
66
67 array = &rt_rq->active;
68 for (i = 0; i < MAX_RT_PRIO; i++) {
69 INIT_LIST_HEAD(array->queue + i);
70 __clear_bit(i, array->bitmap);
71 }
72 /* delimiter for bitsearch: */
73 __set_bit(MAX_RT_PRIO, array->bitmap);
74
75#if defined CONFIG_SMP
76 rt_rq->highest_prio.curr = MAX_RT_PRIO;
77 rt_rq->highest_prio.next = MAX_RT_PRIO;
78 rt_rq->rt_nr_migratory = 0;
79 rt_rq->overloaded = 0;
80 plist_head_init(&rt_rq->pushable_tasks);
81#endif
82
83 rt_rq->rt_time = 0;
84 rt_rq->rt_throttled = 0;
85 rt_rq->rt_runtime = 0;
86 raw_spin_lock_init(&rt_rq->rt_runtime_lock);
87}
88
Gregory Haskins398a1532009-01-14 09:10:04 -050089#ifdef CONFIG_RT_GROUP_SCHED
Peter Zijlstra029632f2011-10-25 10:00:11 +020090static void destroy_rt_bandwidth(struct rt_bandwidth *rt_b)
91{
92 hrtimer_cancel(&rt_b->rt_period_timer);
93}
Gregory Haskins398a1532009-01-14 09:10:04 -050094
Peter Zijlstraa1ba4d82009-04-01 18:40:15 +020095#define rt_entity_is_task(rt_se) (!(rt_se)->my_q)
96
Peter Zijlstra8f488942009-07-24 12:25:30 +020097static inline struct task_struct *rt_task_of(struct sched_rt_entity *rt_se)
98{
99#ifdef CONFIG_SCHED_DEBUG
100 WARN_ON_ONCE(!rt_entity_is_task(rt_se));
101#endif
102 return container_of(rt_se, struct task_struct, rt);
103}
104
Gregory Haskins398a1532009-01-14 09:10:04 -0500105static inline struct rq *rq_of_rt_rq(struct rt_rq *rt_rq)
106{
107 return rt_rq->rq;
108}
109
110static inline struct rt_rq *rt_rq_of_se(struct sched_rt_entity *rt_se)
111{
112 return rt_se->rt_rq;
113}
114
Peter Zijlstra029632f2011-10-25 10:00:11 +0200115void free_rt_sched_group(struct task_group *tg)
116{
117 int i;
118
119 if (tg->rt_se)
120 destroy_rt_bandwidth(&tg->rt_bandwidth);
121
122 for_each_possible_cpu(i) {
123 if (tg->rt_rq)
124 kfree(tg->rt_rq[i]);
125 if (tg->rt_se)
126 kfree(tg->rt_se[i]);
127 }
128
129 kfree(tg->rt_rq);
130 kfree(tg->rt_se);
131}
132
133void init_tg_rt_entry(struct task_group *tg, struct rt_rq *rt_rq,
134 struct sched_rt_entity *rt_se, int cpu,
135 struct sched_rt_entity *parent)
136{
137 struct rq *rq = cpu_rq(cpu);
138
139 rt_rq->highest_prio.curr = MAX_RT_PRIO;
140 rt_rq->rt_nr_boosted = 0;
141 rt_rq->rq = rq;
142 rt_rq->tg = tg;
143
144 tg->rt_rq[cpu] = rt_rq;
145 tg->rt_se[cpu] = rt_se;
146
147 if (!rt_se)
148 return;
149
150 if (!parent)
151 rt_se->rt_rq = &rq->rt;
152 else
153 rt_se->rt_rq = parent->my_q;
154
155 rt_se->my_q = rt_rq;
156 rt_se->parent = parent;
157 INIT_LIST_HEAD(&rt_se->run_list);
158}
159
160int alloc_rt_sched_group(struct task_group *tg, struct task_group *parent)
161{
162 struct rt_rq *rt_rq;
163 struct sched_rt_entity *rt_se;
164 int i;
165
166 tg->rt_rq = kzalloc(sizeof(rt_rq) * nr_cpu_ids, GFP_KERNEL);
167 if (!tg->rt_rq)
168 goto err;
169 tg->rt_se = kzalloc(sizeof(rt_se) * nr_cpu_ids, GFP_KERNEL);
170 if (!tg->rt_se)
171 goto err;
172
173 init_rt_bandwidth(&tg->rt_bandwidth,
174 ktime_to_ns(def_rt_bandwidth.rt_period), 0);
175
176 for_each_possible_cpu(i) {
177 rt_rq = kzalloc_node(sizeof(struct rt_rq),
178 GFP_KERNEL, cpu_to_node(i));
179 if (!rt_rq)
180 goto err;
181
182 rt_se = kzalloc_node(sizeof(struct sched_rt_entity),
183 GFP_KERNEL, cpu_to_node(i));
184 if (!rt_se)
185 goto err_free_rq;
186
187 init_rt_rq(rt_rq, cpu_rq(i));
188 rt_rq->rt_runtime = tg->rt_bandwidth.rt_runtime;
189 init_tg_rt_entry(tg, rt_rq, rt_se, i, parent->rt_se[i]);
190 }
191
192 return 1;
193
194err_free_rq:
195 kfree(rt_rq);
196err:
197 return 0;
198}
199
Gregory Haskins398a1532009-01-14 09:10:04 -0500200#else /* CONFIG_RT_GROUP_SCHED */
201
Peter Zijlstraa1ba4d82009-04-01 18:40:15 +0200202#define rt_entity_is_task(rt_se) (1)
203
Peter Zijlstra8f488942009-07-24 12:25:30 +0200204static inline struct task_struct *rt_task_of(struct sched_rt_entity *rt_se)
205{
206 return container_of(rt_se, struct task_struct, rt);
207}
208
Gregory Haskins398a1532009-01-14 09:10:04 -0500209static inline struct rq *rq_of_rt_rq(struct rt_rq *rt_rq)
210{
211 return container_of(rt_rq, struct rq, rt);
212}
213
214static inline struct rt_rq *rt_rq_of_se(struct sched_rt_entity *rt_se)
215{
216 struct task_struct *p = rt_task_of(rt_se);
217 struct rq *rq = task_rq(p);
218
219 return &rq->rt;
220}
221
Peter Zijlstra029632f2011-10-25 10:00:11 +0200222void free_rt_sched_group(struct task_group *tg) { }
223
224int alloc_rt_sched_group(struct task_group *tg, struct task_group *parent)
225{
226 return 1;
227}
Gregory Haskins398a1532009-01-14 09:10:04 -0500228#endif /* CONFIG_RT_GROUP_SCHED */
229
Steven Rostedt4fd29172008-01-25 21:08:06 +0100230#ifdef CONFIG_SMP
Ingo Molnar84de4272008-01-25 21:08:15 +0100231
Peter Zijlstra38033c32014-01-23 20:32:21 +0100232static int pull_rt_task(struct rq *this_rq);
233
Peter Zijlstradc877342014-02-12 15:47:29 +0100234static inline bool need_pull_rt_task(struct rq *rq, struct task_struct *prev)
235{
236 /* Try to pull RT tasks here if we lower this rq's prio */
237 return rq->rt.highest_prio.curr > prev->prio;
238}
239
Gregory Haskins637f5082008-01-25 21:08:18 +0100240static inline int rt_overloaded(struct rq *rq)
Steven Rostedt4fd29172008-01-25 21:08:06 +0100241{
Gregory Haskins637f5082008-01-25 21:08:18 +0100242 return atomic_read(&rq->rd->rto_count);
Steven Rostedt4fd29172008-01-25 21:08:06 +0100243}
Ingo Molnar84de4272008-01-25 21:08:15 +0100244
Steven Rostedt4fd29172008-01-25 21:08:06 +0100245static inline void rt_set_overload(struct rq *rq)
246{
Gregory Haskins1f11eb62008-06-04 15:04:05 -0400247 if (!rq->online)
248 return;
249
Rusty Russellc6c49272008-11-25 02:35:05 +1030250 cpumask_set_cpu(rq->cpu, rq->rd->rto_mask);
Steven Rostedt4fd29172008-01-25 21:08:06 +0100251 /*
252 * Make sure the mask is visible before we set
253 * the overload count. That is checked to determine
254 * if we should look at the mask. It would be a shame
255 * if we looked at the mask, but the mask was not
256 * updated yet.
Peter Zijlstra7c3f2ab2013-10-15 12:35:07 +0200257 *
258 * Matched by the barrier in pull_rt_task().
Steven Rostedt4fd29172008-01-25 21:08:06 +0100259 */
Peter Zijlstra7c3f2ab2013-10-15 12:35:07 +0200260 smp_wmb();
Gregory Haskins637f5082008-01-25 21:08:18 +0100261 atomic_inc(&rq->rd->rto_count);
Steven Rostedt4fd29172008-01-25 21:08:06 +0100262}
Ingo Molnar84de4272008-01-25 21:08:15 +0100263
Steven Rostedt4fd29172008-01-25 21:08:06 +0100264static inline void rt_clear_overload(struct rq *rq)
265{
Gregory Haskins1f11eb62008-06-04 15:04:05 -0400266 if (!rq->online)
267 return;
268
Steven Rostedt4fd29172008-01-25 21:08:06 +0100269 /* the order here really doesn't matter */
Gregory Haskins637f5082008-01-25 21:08:18 +0100270 atomic_dec(&rq->rd->rto_count);
Rusty Russellc6c49272008-11-25 02:35:05 +1030271 cpumask_clear_cpu(rq->cpu, rq->rd->rto_mask);
Steven Rostedt4fd29172008-01-25 21:08:06 +0100272}
Gregory Haskins73fe6aa2008-01-25 21:08:07 +0100273
Gregory Haskins398a1532009-01-14 09:10:04 -0500274static void update_rt_migration(struct rt_rq *rt_rq)
Gregory Haskins73fe6aa2008-01-25 21:08:07 +0100275{
Peter Zijlstraa1ba4d82009-04-01 18:40:15 +0200276 if (rt_rq->rt_nr_migratory && rt_rq->rt_nr_total > 1) {
Gregory Haskins398a1532009-01-14 09:10:04 -0500277 if (!rt_rq->overloaded) {
278 rt_set_overload(rq_of_rt_rq(rt_rq));
279 rt_rq->overloaded = 1;
Gregory Haskinscdc8eb92008-01-25 21:08:23 +0100280 }
Gregory Haskins398a1532009-01-14 09:10:04 -0500281 } else if (rt_rq->overloaded) {
282 rt_clear_overload(rq_of_rt_rq(rt_rq));
283 rt_rq->overloaded = 0;
Gregory Haskins637f5082008-01-25 21:08:18 +0100284 }
Gregory Haskins73fe6aa2008-01-25 21:08:07 +0100285}
Steven Rostedt4fd29172008-01-25 21:08:06 +0100286
Gregory Haskins398a1532009-01-14 09:10:04 -0500287static void inc_rt_migration(struct sched_rt_entity *rt_se, struct rt_rq *rt_rq)
Peter Zijlstrafa85ae22008-01-25 21:08:29 +0100288{
Peter Zijlstra29baa742012-04-23 12:11:21 +0200289 struct task_struct *p;
290
Peter Zijlstraa1ba4d82009-04-01 18:40:15 +0200291 if (!rt_entity_is_task(rt_se))
292 return;
293
Peter Zijlstra29baa742012-04-23 12:11:21 +0200294 p = rt_task_of(rt_se);
Peter Zijlstraa1ba4d82009-04-01 18:40:15 +0200295 rt_rq = &rq_of_rt_rq(rt_rq)->rt;
296
297 rt_rq->rt_nr_total++;
Peter Zijlstra29baa742012-04-23 12:11:21 +0200298 if (p->nr_cpus_allowed > 1)
Gregory Haskins398a1532009-01-14 09:10:04 -0500299 rt_rq->rt_nr_migratory++;
300
301 update_rt_migration(rt_rq);
Peter Zijlstra6f505b12008-01-25 21:08:30 +0100302}
303
Gregory Haskins398a1532009-01-14 09:10:04 -0500304static void dec_rt_migration(struct sched_rt_entity *rt_se, struct rt_rq *rt_rq)
305{
Peter Zijlstra29baa742012-04-23 12:11:21 +0200306 struct task_struct *p;
307
Peter Zijlstraa1ba4d82009-04-01 18:40:15 +0200308 if (!rt_entity_is_task(rt_se))
309 return;
310
Peter Zijlstra29baa742012-04-23 12:11:21 +0200311 p = rt_task_of(rt_se);
Peter Zijlstraa1ba4d82009-04-01 18:40:15 +0200312 rt_rq = &rq_of_rt_rq(rt_rq)->rt;
313
314 rt_rq->rt_nr_total--;
Peter Zijlstra29baa742012-04-23 12:11:21 +0200315 if (p->nr_cpus_allowed > 1)
Gregory Haskins398a1532009-01-14 09:10:04 -0500316 rt_rq->rt_nr_migratory--;
317
318 update_rt_migration(rt_rq);
319}
320
Steven Rostedt5181f4a42011-06-16 21:55:23 -0400321static inline int has_pushable_tasks(struct rq *rq)
322{
323 return !plist_head_empty(&rq->rt.pushable_tasks);
324}
325
Peter Zijlstradc877342014-02-12 15:47:29 +0100326static inline void set_post_schedule(struct rq *rq)
327{
328 /*
329 * We detect this state here so that we can avoid taking the RQ
330 * lock again later if there is no need to push
331 */
332 rq->post_schedule = has_pushable_tasks(rq);
333}
334
Gregory Haskins917b6272008-12-29 09:39:53 -0500335static void enqueue_pushable_task(struct rq *rq, struct task_struct *p)
336{
337 plist_del(&p->pushable_tasks, &rq->rt.pushable_tasks);
338 plist_node_init(&p->pushable_tasks, p->prio);
339 plist_add(&p->pushable_tasks, &rq->rt.pushable_tasks);
Steven Rostedt5181f4a42011-06-16 21:55:23 -0400340
341 /* Update the highest prio pushable task */
342 if (p->prio < rq->rt.highest_prio.next)
343 rq->rt.highest_prio.next = p->prio;
Gregory Haskins917b6272008-12-29 09:39:53 -0500344}
345
346static void dequeue_pushable_task(struct rq *rq, struct task_struct *p)
347{
348 plist_del(&p->pushable_tasks, &rq->rt.pushable_tasks);
Gregory Haskins917b6272008-12-29 09:39:53 -0500349
Steven Rostedt5181f4a42011-06-16 21:55:23 -0400350 /* Update the new highest prio pushable task */
351 if (has_pushable_tasks(rq)) {
352 p = plist_first_entry(&rq->rt.pushable_tasks,
353 struct task_struct, pushable_tasks);
354 rq->rt.highest_prio.next = p->prio;
355 } else
356 rq->rt.highest_prio.next = MAX_RT_PRIO;
Ingo Molnarbcf08df2008-04-19 12:11:10 +0200357}
358
Gregory Haskins917b6272008-12-29 09:39:53 -0500359#else
360
Peter Zijlstraceacc2c2009-01-16 14:46:40 +0100361static inline void enqueue_pushable_task(struct rq *rq, struct task_struct *p)
362{
363}
364
365static inline void dequeue_pushable_task(struct rq *rq, struct task_struct *p)
366{
367}
368
Gregory Haskinsb07430a2009-01-14 08:55:39 -0500369static inline
Peter Zijlstraceacc2c2009-01-16 14:46:40 +0100370void inc_rt_migration(struct sched_rt_entity *rt_se, struct rt_rq *rt_rq)
371{
372}
373
Gregory Haskinsb07430a2009-01-14 08:55:39 -0500374static inline
Peter Zijlstraceacc2c2009-01-16 14:46:40 +0100375void dec_rt_migration(struct sched_rt_entity *rt_se, struct rt_rq *rt_rq)
376{
377}
Gregory Haskins917b6272008-12-29 09:39:53 -0500378
Peter Zijlstradc877342014-02-12 15:47:29 +0100379static inline bool need_pull_rt_task(struct rq *rq, struct task_struct *prev)
380{
381 return false;
382}
383
384static inline int pull_rt_task(struct rq *this_rq)
385{
386 return 0;
387}
388
389static inline void set_post_schedule(struct rq *rq)
390{
391}
Ingo Molnarbb44e5d2007-07-09 18:51:58 +0200392#endif /* CONFIG_SMP */
393
Peter Zijlstra6f505b12008-01-25 21:08:30 +0100394static inline int on_rt_rq(struct sched_rt_entity *rt_se)
395{
396 return !list_empty(&rt_se->run_list);
397}
398
Peter Zijlstra052f1dc2008-02-13 15:45:40 +0100399#ifdef CONFIG_RT_GROUP_SCHED
Peter Zijlstra6f505b12008-01-25 21:08:30 +0100400
Peter Zijlstra9f0c1e52008-02-13 15:45:39 +0100401static inline u64 sched_rt_runtime(struct rt_rq *rt_rq)
Peter Zijlstra6f505b12008-01-25 21:08:30 +0100402{
403 if (!rt_rq->tg)
Peter Zijlstra9f0c1e52008-02-13 15:45:39 +0100404 return RUNTIME_INF;
Peter Zijlstra6f505b12008-01-25 21:08:30 +0100405
Peter Zijlstraac086bc2008-04-19 19:44:58 +0200406 return rt_rq->rt_runtime;
407}
408
409static inline u64 sched_rt_period(struct rt_rq *rt_rq)
410{
411 return ktime_to_ns(rt_rq->tg->rt_bandwidth.rt_period);
Peter Zijlstra6f505b12008-01-25 21:08:30 +0100412}
413
Cheng Xuec514c42011-05-14 14:20:02 +0800414typedef struct task_group *rt_rq_iter_t;
415
Yong Zhang1c09ab02011-06-28 10:51:31 +0800416static inline struct task_group *next_task_group(struct task_group *tg)
417{
418 do {
419 tg = list_entry_rcu(tg->list.next,
420 typeof(struct task_group), list);
421 } while (&tg->list != &task_groups && task_group_is_autogroup(tg));
422
423 if (&tg->list == &task_groups)
424 tg = NULL;
425
426 return tg;
427}
428
429#define for_each_rt_rq(rt_rq, iter, rq) \
430 for (iter = container_of(&task_groups, typeof(*iter), list); \
431 (iter = next_task_group(iter)) && \
432 (rt_rq = iter->rt_rq[cpu_of(rq)]);)
Cheng Xuec514c42011-05-14 14:20:02 +0800433
Peter Zijlstra6f505b12008-01-25 21:08:30 +0100434#define for_each_sched_rt_entity(rt_se) \
435 for (; rt_se; rt_se = rt_se->parent)
436
437static inline struct rt_rq *group_rt_rq(struct sched_rt_entity *rt_se)
438{
439 return rt_se->my_q;
440}
441
Thomas Gleixner37dad3f2010-01-20 20:59:01 +0000442static void enqueue_rt_entity(struct sched_rt_entity *rt_se, bool head);
Peter Zijlstra6f505b12008-01-25 21:08:30 +0100443static void dequeue_rt_entity(struct sched_rt_entity *rt_se);
444
Peter Zijlstra9f0c1e52008-02-13 15:45:39 +0100445static void sched_rt_rq_enqueue(struct rt_rq *rt_rq)
Peter Zijlstra6f505b12008-01-25 21:08:30 +0100446{
Dario Faggiolif6121f42008-10-03 17:40:46 +0200447 struct task_struct *curr = rq_of_rt_rq(rt_rq)->curr;
Yong Zhang74b7eb52010-01-29 14:57:52 +0800448 struct sched_rt_entity *rt_se;
449
Balbir Singh0c3b9162011-03-03 17:04:35 +0530450 int cpu = cpu_of(rq_of_rt_rq(rt_rq));
451
452 rt_se = rt_rq->tg->rt_se[cpu];
Peter Zijlstra6f505b12008-01-25 21:08:30 +0100453
Dario Faggiolif6121f42008-10-03 17:40:46 +0200454 if (rt_rq->rt_nr_running) {
455 if (rt_se && !on_rt_rq(rt_se))
Thomas Gleixner37dad3f2010-01-20 20:59:01 +0000456 enqueue_rt_entity(rt_se, false);
Gregory Haskinse864c492008-12-29 09:39:49 -0500457 if (rt_rq->highest_prio.curr < curr->prio)
Peter Zijlstra10203872008-01-25 21:08:32 +0100458 resched_task(curr);
Peter Zijlstra6f505b12008-01-25 21:08:30 +0100459 }
460}
461
Peter Zijlstra9f0c1e52008-02-13 15:45:39 +0100462static void sched_rt_rq_dequeue(struct rt_rq *rt_rq)
Peter Zijlstra6f505b12008-01-25 21:08:30 +0100463{
Yong Zhang74b7eb52010-01-29 14:57:52 +0800464 struct sched_rt_entity *rt_se;
Balbir Singh0c3b9162011-03-03 17:04:35 +0530465 int cpu = cpu_of(rq_of_rt_rq(rt_rq));
Yong Zhang74b7eb52010-01-29 14:57:52 +0800466
Balbir Singh0c3b9162011-03-03 17:04:35 +0530467 rt_se = rt_rq->tg->rt_se[cpu];
Peter Zijlstra6f505b12008-01-25 21:08:30 +0100468
469 if (rt_se && on_rt_rq(rt_se))
470 dequeue_rt_entity(rt_se);
471}
472
Peter Zijlstra23b0fdf2008-02-13 15:45:39 +0100473static int rt_se_boosted(struct sched_rt_entity *rt_se)
474{
475 struct rt_rq *rt_rq = group_rt_rq(rt_se);
476 struct task_struct *p;
477
478 if (rt_rq)
479 return !!rt_rq->rt_nr_boosted;
480
481 p = rt_task_of(rt_se);
482 return p->prio != p->normal_prio;
483}
484
Peter Zijlstrad0b27fa2008-04-19 19:44:57 +0200485#ifdef CONFIG_SMP
Rusty Russellc6c49272008-11-25 02:35:05 +1030486static inline const struct cpumask *sched_rt_period_mask(void)
Peter Zijlstrad0b27fa2008-04-19 19:44:57 +0200487{
Nathan Zimmer424c93f2013-05-09 11:24:03 -0500488 return this_rq()->rd->span;
Peter Zijlstrad0b27fa2008-04-19 19:44:57 +0200489}
490#else
Rusty Russellc6c49272008-11-25 02:35:05 +1030491static inline const struct cpumask *sched_rt_period_mask(void)
Peter Zijlstrad0b27fa2008-04-19 19:44:57 +0200492{
Rusty Russellc6c49272008-11-25 02:35:05 +1030493 return cpu_online_mask;
Peter Zijlstrad0b27fa2008-04-19 19:44:57 +0200494}
495#endif
496
497static inline
498struct rt_rq *sched_rt_period_rt_rq(struct rt_bandwidth *rt_b, int cpu)
499{
500 return container_of(rt_b, struct task_group, rt_bandwidth)->rt_rq[cpu];
501}
502
Peter Zijlstraac086bc2008-04-19 19:44:58 +0200503static inline struct rt_bandwidth *sched_rt_bandwidth(struct rt_rq *rt_rq)
504{
505 return &rt_rq->tg->rt_bandwidth;
506}
507
Dhaval Giani55e12e52008-06-24 23:39:43 +0530508#else /* !CONFIG_RT_GROUP_SCHED */
Peter Zijlstra6f505b12008-01-25 21:08:30 +0100509
Peter Zijlstra9f0c1e52008-02-13 15:45:39 +0100510static inline u64 sched_rt_runtime(struct rt_rq *rt_rq)
Peter Zijlstra6f505b12008-01-25 21:08:30 +0100511{
Peter Zijlstraac086bc2008-04-19 19:44:58 +0200512 return rt_rq->rt_runtime;
513}
514
515static inline u64 sched_rt_period(struct rt_rq *rt_rq)
516{
517 return ktime_to_ns(def_rt_bandwidth.rt_period);
Peter Zijlstra6f505b12008-01-25 21:08:30 +0100518}
519
Cheng Xuec514c42011-05-14 14:20:02 +0800520typedef struct rt_rq *rt_rq_iter_t;
521
522#define for_each_rt_rq(rt_rq, iter, rq) \
523 for ((void) iter, rt_rq = &rq->rt; rt_rq; rt_rq = NULL)
524
Peter Zijlstra6f505b12008-01-25 21:08:30 +0100525#define for_each_sched_rt_entity(rt_se) \
526 for (; rt_se; rt_se = NULL)
527
528static inline struct rt_rq *group_rt_rq(struct sched_rt_entity *rt_se)
529{
530 return NULL;
531}
532
Peter Zijlstra9f0c1e52008-02-13 15:45:39 +0100533static inline void sched_rt_rq_enqueue(struct rt_rq *rt_rq)
Peter Zijlstra6f505b12008-01-25 21:08:30 +0100534{
John Blackwoodf3ade832008-08-26 15:09:43 -0400535 if (rt_rq->rt_nr_running)
536 resched_task(rq_of_rt_rq(rt_rq)->curr);
Peter Zijlstra6f505b12008-01-25 21:08:30 +0100537}
538
Peter Zijlstra9f0c1e52008-02-13 15:45:39 +0100539static inline void sched_rt_rq_dequeue(struct rt_rq *rt_rq)
Peter Zijlstra6f505b12008-01-25 21:08:30 +0100540{
541}
542
Rusty Russellc6c49272008-11-25 02:35:05 +1030543static inline const struct cpumask *sched_rt_period_mask(void)
Peter Zijlstrad0b27fa2008-04-19 19:44:57 +0200544{
Rusty Russellc6c49272008-11-25 02:35:05 +1030545 return cpu_online_mask;
Peter Zijlstrad0b27fa2008-04-19 19:44:57 +0200546}
547
548static inline
549struct rt_rq *sched_rt_period_rt_rq(struct rt_bandwidth *rt_b, int cpu)
550{
551 return &cpu_rq(cpu)->rt;
552}
553
Peter Zijlstraac086bc2008-04-19 19:44:58 +0200554static inline struct rt_bandwidth *sched_rt_bandwidth(struct rt_rq *rt_rq)
555{
556 return &def_rt_bandwidth;
557}
558
Dhaval Giani55e12e52008-06-24 23:39:43 +0530559#endif /* CONFIG_RT_GROUP_SCHED */
Peter Zijlstra6f505b12008-01-25 21:08:30 +0100560
Juri Lellifaa59932014-02-21 11:37:15 +0100561bool sched_rt_bandwidth_account(struct rt_rq *rt_rq)
562{
563 struct rt_bandwidth *rt_b = sched_rt_bandwidth(rt_rq);
564
565 return (hrtimer_active(&rt_b->rt_period_timer) ||
566 rt_rq->rt_time < rt_b->rt_runtime);
567}
568
Peter Zijlstrab79f3832008-06-19 14:22:25 +0200569#ifdef CONFIG_SMP
Peter Zijlstra78333cd2008-09-23 15:33:43 +0200570/*
571 * We ran out of runtime, see if we can borrow some from our neighbours.
572 */
Peter Zijlstrab79f3832008-06-19 14:22:25 +0200573static int do_balance_runtime(struct rt_rq *rt_rq)
Peter Zijlstraac086bc2008-04-19 19:44:58 +0200574{
575 struct rt_bandwidth *rt_b = sched_rt_bandwidth(rt_rq);
Shawn Bohreraa7f6732013-01-14 11:55:31 -0600576 struct root_domain *rd = rq_of_rt_rq(rt_rq)->rd;
Peter Zijlstraac086bc2008-04-19 19:44:58 +0200577 int i, weight, more = 0;
578 u64 rt_period;
579
Rusty Russellc6c49272008-11-25 02:35:05 +1030580 weight = cpumask_weight(rd->span);
Peter Zijlstraac086bc2008-04-19 19:44:58 +0200581
Thomas Gleixner0986b112009-11-17 15:32:06 +0100582 raw_spin_lock(&rt_b->rt_runtime_lock);
Peter Zijlstraac086bc2008-04-19 19:44:58 +0200583 rt_period = ktime_to_ns(rt_b->rt_period);
Rusty Russellc6c49272008-11-25 02:35:05 +1030584 for_each_cpu(i, rd->span) {
Peter Zijlstraac086bc2008-04-19 19:44:58 +0200585 struct rt_rq *iter = sched_rt_period_rt_rq(rt_b, i);
586 s64 diff;
587
588 if (iter == rt_rq)
589 continue;
590
Thomas Gleixner0986b112009-11-17 15:32:06 +0100591 raw_spin_lock(&iter->rt_runtime_lock);
Peter Zijlstra78333cd2008-09-23 15:33:43 +0200592 /*
593 * Either all rqs have inf runtime and there's nothing to steal
594 * or __disable_runtime() below sets a specific rq to inf to
595 * indicate its been disabled and disalow stealing.
596 */
Peter Zijlstra7def2be2008-06-05 14:49:58 +0200597 if (iter->rt_runtime == RUNTIME_INF)
598 goto next;
599
Peter Zijlstra78333cd2008-09-23 15:33:43 +0200600 /*
601 * From runqueues with spare time, take 1/n part of their
602 * spare time, but no more than our period.
603 */
Peter Zijlstraac086bc2008-04-19 19:44:58 +0200604 diff = iter->rt_runtime - iter->rt_time;
605 if (diff > 0) {
Peter Zijlstra58838cf2008-07-24 12:43:13 +0200606 diff = div_u64((u64)diff, weight);
Peter Zijlstraac086bc2008-04-19 19:44:58 +0200607 if (rt_rq->rt_runtime + diff > rt_period)
608 diff = rt_period - rt_rq->rt_runtime;
609 iter->rt_runtime -= diff;
610 rt_rq->rt_runtime += diff;
611 more = 1;
612 if (rt_rq->rt_runtime == rt_period) {
Thomas Gleixner0986b112009-11-17 15:32:06 +0100613 raw_spin_unlock(&iter->rt_runtime_lock);
Peter Zijlstraac086bc2008-04-19 19:44:58 +0200614 break;
615 }
616 }
Peter Zijlstra7def2be2008-06-05 14:49:58 +0200617next:
Thomas Gleixner0986b112009-11-17 15:32:06 +0100618 raw_spin_unlock(&iter->rt_runtime_lock);
Peter Zijlstraac086bc2008-04-19 19:44:58 +0200619 }
Thomas Gleixner0986b112009-11-17 15:32:06 +0100620 raw_spin_unlock(&rt_b->rt_runtime_lock);
Peter Zijlstraac086bc2008-04-19 19:44:58 +0200621
622 return more;
623}
Peter Zijlstra7def2be2008-06-05 14:49:58 +0200624
Peter Zijlstra78333cd2008-09-23 15:33:43 +0200625/*
626 * Ensure this RQ takes back all the runtime it lend to its neighbours.
627 */
Peter Zijlstra7def2be2008-06-05 14:49:58 +0200628static void __disable_runtime(struct rq *rq)
629{
630 struct root_domain *rd = rq->rd;
Cheng Xuec514c42011-05-14 14:20:02 +0800631 rt_rq_iter_t iter;
Peter Zijlstra7def2be2008-06-05 14:49:58 +0200632 struct rt_rq *rt_rq;
633
634 if (unlikely(!scheduler_running))
635 return;
636
Cheng Xuec514c42011-05-14 14:20:02 +0800637 for_each_rt_rq(rt_rq, iter, rq) {
Peter Zijlstra7def2be2008-06-05 14:49:58 +0200638 struct rt_bandwidth *rt_b = sched_rt_bandwidth(rt_rq);
639 s64 want;
640 int i;
641
Thomas Gleixner0986b112009-11-17 15:32:06 +0100642 raw_spin_lock(&rt_b->rt_runtime_lock);
643 raw_spin_lock(&rt_rq->rt_runtime_lock);
Peter Zijlstra78333cd2008-09-23 15:33:43 +0200644 /*
645 * Either we're all inf and nobody needs to borrow, or we're
646 * already disabled and thus have nothing to do, or we have
647 * exactly the right amount of runtime to take out.
648 */
Peter Zijlstra7def2be2008-06-05 14:49:58 +0200649 if (rt_rq->rt_runtime == RUNTIME_INF ||
650 rt_rq->rt_runtime == rt_b->rt_runtime)
651 goto balanced;
Thomas Gleixner0986b112009-11-17 15:32:06 +0100652 raw_spin_unlock(&rt_rq->rt_runtime_lock);
Peter Zijlstra7def2be2008-06-05 14:49:58 +0200653
Peter Zijlstra78333cd2008-09-23 15:33:43 +0200654 /*
655 * Calculate the difference between what we started out with
656 * and what we current have, that's the amount of runtime
657 * we lend and now have to reclaim.
658 */
Peter Zijlstra7def2be2008-06-05 14:49:58 +0200659 want = rt_b->rt_runtime - rt_rq->rt_runtime;
660
Peter Zijlstra78333cd2008-09-23 15:33:43 +0200661 /*
662 * Greedy reclaim, take back as much as we can.
663 */
Rusty Russellc6c49272008-11-25 02:35:05 +1030664 for_each_cpu(i, rd->span) {
Peter Zijlstra7def2be2008-06-05 14:49:58 +0200665 struct rt_rq *iter = sched_rt_period_rt_rq(rt_b, i);
666 s64 diff;
667
Peter Zijlstra78333cd2008-09-23 15:33:43 +0200668 /*
669 * Can't reclaim from ourselves or disabled runqueues.
670 */
Peter Zijlstraf1679d02008-08-14 15:49:00 +0200671 if (iter == rt_rq || iter->rt_runtime == RUNTIME_INF)
Peter Zijlstra7def2be2008-06-05 14:49:58 +0200672 continue;
673
Thomas Gleixner0986b112009-11-17 15:32:06 +0100674 raw_spin_lock(&iter->rt_runtime_lock);
Peter Zijlstra7def2be2008-06-05 14:49:58 +0200675 if (want > 0) {
676 diff = min_t(s64, iter->rt_runtime, want);
677 iter->rt_runtime -= diff;
678 want -= diff;
679 } else {
680 iter->rt_runtime -= want;
681 want -= want;
682 }
Thomas Gleixner0986b112009-11-17 15:32:06 +0100683 raw_spin_unlock(&iter->rt_runtime_lock);
Peter Zijlstra7def2be2008-06-05 14:49:58 +0200684
685 if (!want)
686 break;
687 }
688
Thomas Gleixner0986b112009-11-17 15:32:06 +0100689 raw_spin_lock(&rt_rq->rt_runtime_lock);
Peter Zijlstra78333cd2008-09-23 15:33:43 +0200690 /*
691 * We cannot be left wanting - that would mean some runtime
692 * leaked out of the system.
693 */
Peter Zijlstra7def2be2008-06-05 14:49:58 +0200694 BUG_ON(want);
695balanced:
Peter Zijlstra78333cd2008-09-23 15:33:43 +0200696 /*
697 * Disable all the borrow logic by pretending we have inf
698 * runtime - in which case borrowing doesn't make sense.
699 */
Peter Zijlstra7def2be2008-06-05 14:49:58 +0200700 rt_rq->rt_runtime = RUNTIME_INF;
Peter Boonstoppela4c96ae2012-08-09 15:34:47 -0700701 rt_rq->rt_throttled = 0;
Thomas Gleixner0986b112009-11-17 15:32:06 +0100702 raw_spin_unlock(&rt_rq->rt_runtime_lock);
703 raw_spin_unlock(&rt_b->rt_runtime_lock);
Peter Zijlstra7def2be2008-06-05 14:49:58 +0200704 }
705}
706
Peter Zijlstra7def2be2008-06-05 14:49:58 +0200707static void __enable_runtime(struct rq *rq)
708{
Cheng Xuec514c42011-05-14 14:20:02 +0800709 rt_rq_iter_t iter;
Peter Zijlstra7def2be2008-06-05 14:49:58 +0200710 struct rt_rq *rt_rq;
711
712 if (unlikely(!scheduler_running))
713 return;
714
Peter Zijlstra78333cd2008-09-23 15:33:43 +0200715 /*
716 * Reset each runqueue's bandwidth settings
717 */
Cheng Xuec514c42011-05-14 14:20:02 +0800718 for_each_rt_rq(rt_rq, iter, rq) {
Peter Zijlstra7def2be2008-06-05 14:49:58 +0200719 struct rt_bandwidth *rt_b = sched_rt_bandwidth(rt_rq);
720
Thomas Gleixner0986b112009-11-17 15:32:06 +0100721 raw_spin_lock(&rt_b->rt_runtime_lock);
722 raw_spin_lock(&rt_rq->rt_runtime_lock);
Peter Zijlstra7def2be2008-06-05 14:49:58 +0200723 rt_rq->rt_runtime = rt_b->rt_runtime;
724 rt_rq->rt_time = 0;
Zhang, Yanminbaf25732008-09-09 11:26:33 +0800725 rt_rq->rt_throttled = 0;
Thomas Gleixner0986b112009-11-17 15:32:06 +0100726 raw_spin_unlock(&rt_rq->rt_runtime_lock);
727 raw_spin_unlock(&rt_b->rt_runtime_lock);
Peter Zijlstra7def2be2008-06-05 14:49:58 +0200728 }
729}
730
Peter Zijlstraeff65492008-06-19 14:22:26 +0200731static int balance_runtime(struct rt_rq *rt_rq)
732{
733 int more = 0;
734
Peter Zijlstra4a6184c2011-10-06 22:39:14 +0200735 if (!sched_feat(RT_RUNTIME_SHARE))
736 return more;
737
Peter Zijlstraeff65492008-06-19 14:22:26 +0200738 if (rt_rq->rt_time > rt_rq->rt_runtime) {
Thomas Gleixner0986b112009-11-17 15:32:06 +0100739 raw_spin_unlock(&rt_rq->rt_runtime_lock);
Peter Zijlstraeff65492008-06-19 14:22:26 +0200740 more = do_balance_runtime(rt_rq);
Thomas Gleixner0986b112009-11-17 15:32:06 +0100741 raw_spin_lock(&rt_rq->rt_runtime_lock);
Peter Zijlstraeff65492008-06-19 14:22:26 +0200742 }
743
744 return more;
745}
Dhaval Giani55e12e52008-06-24 23:39:43 +0530746#else /* !CONFIG_SMP */
Peter Zijlstraeff65492008-06-19 14:22:26 +0200747static inline int balance_runtime(struct rt_rq *rt_rq)
748{
749 return 0;
750}
Dhaval Giani55e12e52008-06-24 23:39:43 +0530751#endif /* CONFIG_SMP */
Peter Zijlstra6f505b12008-01-25 21:08:30 +0100752
753static int do_sched_rt_period_timer(struct rt_bandwidth *rt_b, int overrun)
754{
Peter Zijlstra42c62a52011-10-18 22:03:48 +0200755 int i, idle = 1, throttled = 0;
Rusty Russellc6c49272008-11-25 02:35:05 +1030756 const struct cpumask *span;
Peter Zijlstrad0b27fa2008-04-19 19:44:57 +0200757
Peter Zijlstrad0b27fa2008-04-19 19:44:57 +0200758 span = sched_rt_period_mask();
Mike Galbraithe221d022012-08-07 10:02:38 +0200759#ifdef CONFIG_RT_GROUP_SCHED
760 /*
761 * FIXME: isolated CPUs should really leave the root task group,
762 * whether they are isolcpus or were isolated via cpusets, lest
763 * the timer run on a CPU which does not service all runqueues,
764 * potentially leaving other CPUs indefinitely throttled. If
765 * isolation is really required, the user will turn the throttle
766 * off to kill the perturbations it causes anyway. Meanwhile,
767 * this maintains functionality for boot and/or troubleshooting.
768 */
769 if (rt_b == &root_task_group.rt_bandwidth)
770 span = cpu_online_mask;
771#endif
Rusty Russellc6c49272008-11-25 02:35:05 +1030772 for_each_cpu(i, span) {
Peter Zijlstrad0b27fa2008-04-19 19:44:57 +0200773 int enqueue = 0;
774 struct rt_rq *rt_rq = sched_rt_period_rt_rq(rt_b, i);
775 struct rq *rq = rq_of_rt_rq(rt_rq);
776
Thomas Gleixner05fa7852009-11-17 14:28:38 +0100777 raw_spin_lock(&rq->lock);
Peter Zijlstrad0b27fa2008-04-19 19:44:57 +0200778 if (rt_rq->rt_time) {
779 u64 runtime;
780
Thomas Gleixner0986b112009-11-17 15:32:06 +0100781 raw_spin_lock(&rt_rq->rt_runtime_lock);
Peter Zijlstraeff65492008-06-19 14:22:26 +0200782 if (rt_rq->rt_throttled)
783 balance_runtime(rt_rq);
Peter Zijlstrad0b27fa2008-04-19 19:44:57 +0200784 runtime = rt_rq->rt_runtime;
785 rt_rq->rt_time -= min(rt_rq->rt_time, overrun*runtime);
786 if (rt_rq->rt_throttled && rt_rq->rt_time < runtime) {
787 rt_rq->rt_throttled = 0;
788 enqueue = 1;
Mike Galbraith61eadef2011-04-29 08:36:50 +0200789
790 /*
791 * Force a clock update if the CPU was idle,
792 * lest wakeup -> unthrottle time accumulate.
793 */
794 if (rt_rq->rt_nr_running && rq->curr == rq->idle)
795 rq->skip_clock_update = -1;
Peter Zijlstrad0b27fa2008-04-19 19:44:57 +0200796 }
797 if (rt_rq->rt_time || rt_rq->rt_nr_running)
798 idle = 0;
Thomas Gleixner0986b112009-11-17 15:32:06 +0100799 raw_spin_unlock(&rt_rq->rt_runtime_lock);
Balbir Singh0c3b9162011-03-03 17:04:35 +0530800 } else if (rt_rq->rt_nr_running) {
Peter Zijlstra8a8cde12008-06-19 14:22:28 +0200801 idle = 0;
Balbir Singh0c3b9162011-03-03 17:04:35 +0530802 if (!rt_rq_throttled(rt_rq))
803 enqueue = 1;
804 }
Peter Zijlstra42c62a52011-10-18 22:03:48 +0200805 if (rt_rq->rt_throttled)
806 throttled = 1;
Peter Zijlstrad0b27fa2008-04-19 19:44:57 +0200807
808 if (enqueue)
809 sched_rt_rq_enqueue(rt_rq);
Thomas Gleixner05fa7852009-11-17 14:28:38 +0100810 raw_spin_unlock(&rq->lock);
Peter Zijlstrad0b27fa2008-04-19 19:44:57 +0200811 }
812
Peter Zijlstra42c62a52011-10-18 22:03:48 +0200813 if (!throttled && (!rt_bandwidth_enabled() || rt_b->rt_runtime == RUNTIME_INF))
814 return 1;
815
Peter Zijlstrad0b27fa2008-04-19 19:44:57 +0200816 return idle;
817}
818
Peter Zijlstra6f505b12008-01-25 21:08:30 +0100819static inline int rt_se_prio(struct sched_rt_entity *rt_se)
820{
Peter Zijlstra052f1dc2008-02-13 15:45:40 +0100821#ifdef CONFIG_RT_GROUP_SCHED
Peter Zijlstra6f505b12008-01-25 21:08:30 +0100822 struct rt_rq *rt_rq = group_rt_rq(rt_se);
823
824 if (rt_rq)
Gregory Haskinse864c492008-12-29 09:39:49 -0500825 return rt_rq->highest_prio.curr;
Peter Zijlstra6f505b12008-01-25 21:08:30 +0100826#endif
827
828 return rt_task_of(rt_se)->prio;
829}
830
Peter Zijlstra9f0c1e52008-02-13 15:45:39 +0100831static int sched_rt_runtime_exceeded(struct rt_rq *rt_rq)
Peter Zijlstra6f505b12008-01-25 21:08:30 +0100832{
Peter Zijlstra9f0c1e52008-02-13 15:45:39 +0100833 u64 runtime = sched_rt_runtime(rt_rq);
Peter Zijlstrafa85ae22008-01-25 21:08:29 +0100834
Peter Zijlstrafa85ae22008-01-25 21:08:29 +0100835 if (rt_rq->rt_throttled)
Peter Zijlstra23b0fdf2008-02-13 15:45:39 +0100836 return rt_rq_throttled(rt_rq);
Peter Zijlstrafa85ae22008-01-25 21:08:29 +0100837
Shan Hai5b680fd2011-11-29 11:03:56 +0800838 if (runtime >= sched_rt_period(rt_rq))
Peter Zijlstraac086bc2008-04-19 19:44:58 +0200839 return 0;
840
Peter Zijlstrab79f3832008-06-19 14:22:25 +0200841 balance_runtime(rt_rq);
842 runtime = sched_rt_runtime(rt_rq);
843 if (runtime == RUNTIME_INF)
844 return 0;
Peter Zijlstraac086bc2008-04-19 19:44:58 +0200845
Peter Zijlstra9f0c1e52008-02-13 15:45:39 +0100846 if (rt_rq->rt_time > runtime) {
Peter Zijlstra7abc63b2011-10-18 22:03:48 +0200847 struct rt_bandwidth *rt_b = sched_rt_bandwidth(rt_rq);
848
849 /*
850 * Don't actually throttle groups that have no runtime assigned
851 * but accrue some time due to boosting.
852 */
853 if (likely(rt_b->rt_runtime)) {
Peter Zijlstra3ccf3e82012-02-27 10:47:00 +0100854 static bool once = false;
855
Peter Zijlstra7abc63b2011-10-18 22:03:48 +0200856 rt_rq->rt_throttled = 1;
Peter Zijlstra3ccf3e82012-02-27 10:47:00 +0100857
858 if (!once) {
859 once = true;
860 printk_sched("sched: RT throttling activated\n");
861 }
Peter Zijlstra7abc63b2011-10-18 22:03:48 +0200862 } else {
863 /*
864 * In case we did anyway, make it go away,
865 * replenishment is a joke, since it will replenish us
866 * with exactly 0 ns.
867 */
868 rt_rq->rt_time = 0;
869 }
870
Peter Zijlstra23b0fdf2008-02-13 15:45:39 +0100871 if (rt_rq_throttled(rt_rq)) {
Peter Zijlstra9f0c1e52008-02-13 15:45:39 +0100872 sched_rt_rq_dequeue(rt_rq);
Peter Zijlstra23b0fdf2008-02-13 15:45:39 +0100873 return 1;
874 }
Peter Zijlstrafa85ae22008-01-25 21:08:29 +0100875 }
876
877 return 0;
878}
879
Ingo Molnarbb44e5d2007-07-09 18:51:58 +0200880/*
881 * Update the current task's runtime statistics. Skip current tasks that
882 * are not in our scheduling class.
883 */
Alexey Dobriyana9957442007-10-15 17:00:13 +0200884static void update_curr_rt(struct rq *rq)
Ingo Molnarbb44e5d2007-07-09 18:51:58 +0200885{
886 struct task_struct *curr = rq->curr;
Peter Zijlstra6f505b12008-01-25 21:08:30 +0100887 struct sched_rt_entity *rt_se = &curr->rt;
888 struct rt_rq *rt_rq = rt_rq_of_se(rt_se);
Ingo Molnarbb44e5d2007-07-09 18:51:58 +0200889 u64 delta_exec;
890
Peter Zijlstra06c3bc62011-02-02 13:19:48 +0100891 if (curr->sched_class != &rt_sched_class)
Ingo Molnarbb44e5d2007-07-09 18:51:58 +0200892 return;
893
Frederic Weisbecker78becc22013-04-12 01:51:02 +0200894 delta_exec = rq_clock_task(rq) - curr->se.exec_start;
Kirill Tkhaifc79e242013-01-30 16:50:36 +0400895 if (unlikely((s64)delta_exec <= 0))
896 return;
Ingo Molnar6cfb0d52007-08-02 17:41:40 +0200897
Peter Zijlstra42c62a52011-10-18 22:03:48 +0200898 schedstat_set(curr->se.statistics.exec_max,
899 max(curr->se.statistics.exec_max, delta_exec));
Ingo Molnarbb44e5d2007-07-09 18:51:58 +0200900
901 curr->se.sum_exec_runtime += delta_exec;
Frank Mayharf06febc2008-09-12 09:54:39 -0700902 account_group_exec_runtime(curr, delta_exec);
903
Frederic Weisbecker78becc22013-04-12 01:51:02 +0200904 curr->se.exec_start = rq_clock_task(rq);
Srivatsa Vaddagirid842de82007-12-02 20:04:49 +0100905 cpuacct_charge(curr, delta_exec);
Peter Zijlstrafa85ae22008-01-25 21:08:29 +0100906
Peter Zijlstrae9e92502009-09-01 10:34:37 +0200907 sched_rt_avg_update(rq, delta_exec);
908
Peter Zijlstra0b148fa2008-08-19 12:33:04 +0200909 if (!rt_bandwidth_enabled())
910 return;
911
Dhaval Giani354d60c2008-04-19 19:44:59 +0200912 for_each_sched_rt_entity(rt_se) {
913 rt_rq = rt_rq_of_se(rt_se);
914
Peter Zijlstracc2991c2008-08-19 12:33:03 +0200915 if (sched_rt_runtime(rt_rq) != RUNTIME_INF) {
Thomas Gleixner0986b112009-11-17 15:32:06 +0100916 raw_spin_lock(&rt_rq->rt_runtime_lock);
Peter Zijlstracc2991c2008-08-19 12:33:03 +0200917 rt_rq->rt_time += delta_exec;
918 if (sched_rt_runtime_exceeded(rt_rq))
919 resched_task(curr);
Thomas Gleixner0986b112009-11-17 15:32:06 +0100920 raw_spin_unlock(&rt_rq->rt_runtime_lock);
Peter Zijlstracc2991c2008-08-19 12:33:03 +0200921 }
Dhaval Giani354d60c2008-04-19 19:44:59 +0200922 }
Ingo Molnarbb44e5d2007-07-09 18:51:58 +0200923}
924
Gregory Haskins398a1532009-01-14 09:10:04 -0500925#if defined CONFIG_SMP
Gregory Haskinse864c492008-12-29 09:39:49 -0500926
Gregory Haskins398a1532009-01-14 09:10:04 -0500927static void
928inc_rt_prio_smp(struct rt_rq *rt_rq, int prio, int prev_prio)
Steven Rostedt63489e42008-01-25 21:08:03 +0100929{
Gregory Haskins4d984272008-12-29 09:39:49 -0500930 struct rq *rq = rq_of_rt_rq(rt_rq);
Gregory Haskins4d984272008-12-29 09:39:49 -0500931
Kirill Tkhai757dfca2013-11-27 19:59:13 +0400932#ifdef CONFIG_RT_GROUP_SCHED
933 /*
934 * Change rq's cpupri only if rt_rq is the top queue.
935 */
936 if (&rq->rt != rt_rq)
937 return;
938#endif
Steven Rostedt5181f4a42011-06-16 21:55:23 -0400939 if (rq->online && prio < prev_prio)
940 cpupri_set(&rq->rd->cpupri, rq->cpu, prio);
Steven Rostedt63489e42008-01-25 21:08:03 +0100941}
Peter Zijlstra6f505b12008-01-25 21:08:30 +0100942
Gregory Haskins398a1532009-01-14 09:10:04 -0500943static void
944dec_rt_prio_smp(struct rt_rq *rt_rq, int prio, int prev_prio)
Steven Rostedt63489e42008-01-25 21:08:03 +0100945{
Gregory Haskins4d984272008-12-29 09:39:49 -0500946 struct rq *rq = rq_of_rt_rq(rt_rq);
Gregory Haskins6e0534f2008-05-12 21:21:01 +0200947
Kirill Tkhai757dfca2013-11-27 19:59:13 +0400948#ifdef CONFIG_RT_GROUP_SCHED
949 /*
950 * Change rq's cpupri only if rt_rq is the top queue.
951 */
952 if (&rq->rt != rt_rq)
953 return;
954#endif
Gregory Haskins398a1532009-01-14 09:10:04 -0500955 if (rq->online && rt_rq->highest_prio.curr != prev_prio)
956 cpupri_set(&rq->rd->cpupri, rq->cpu, rt_rq->highest_prio.curr);
957}
958
959#else /* CONFIG_SMP */
960
961static inline
962void inc_rt_prio_smp(struct rt_rq *rt_rq, int prio, int prev_prio) {}
963static inline
964void dec_rt_prio_smp(struct rt_rq *rt_rq, int prio, int prev_prio) {}
965
966#endif /* CONFIG_SMP */
967
Steven Rostedt63489e42008-01-25 21:08:03 +0100968#if defined CONFIG_SMP || defined CONFIG_RT_GROUP_SCHED
Gregory Haskins398a1532009-01-14 09:10:04 -0500969static void
970inc_rt_prio(struct rt_rq *rt_rq, int prio)
971{
972 int prev_prio = rt_rq->highest_prio.curr;
Steven Rostedt63489e42008-01-25 21:08:03 +0100973
Gregory Haskins398a1532009-01-14 09:10:04 -0500974 if (prio < prev_prio)
975 rt_rq->highest_prio.curr = prio;
976
977 inc_rt_prio_smp(rt_rq, prio, prev_prio);
978}
979
980static void
981dec_rt_prio(struct rt_rq *rt_rq, int prio)
982{
983 int prev_prio = rt_rq->highest_prio.curr;
984
985 if (rt_rq->rt_nr_running) {
986
987 WARN_ON(prio < prev_prio);
Gregory Haskinse864c492008-12-29 09:39:49 -0500988
989 /*
Gregory Haskins398a1532009-01-14 09:10:04 -0500990 * This may have been our highest task, and therefore
991 * we may have some recomputation to do
Gregory Haskinse864c492008-12-29 09:39:49 -0500992 */
Gregory Haskins398a1532009-01-14 09:10:04 -0500993 if (prio == prev_prio) {
Gregory Haskinse864c492008-12-29 09:39:49 -0500994 struct rt_prio_array *array = &rt_rq->active;
995
996 rt_rq->highest_prio.curr =
Steven Rostedt764a9d62008-01-25 21:08:04 +0100997 sched_find_first_bit(array->bitmap);
Gregory Haskinse864c492008-12-29 09:39:49 -0500998 }
999
Steven Rostedt764a9d62008-01-25 21:08:04 +01001000 } else
Gregory Haskinse864c492008-12-29 09:39:49 -05001001 rt_rq->highest_prio.curr = MAX_RT_PRIO;
Gregory Haskins73fe6aa2008-01-25 21:08:07 +01001002
Gregory Haskins398a1532009-01-14 09:10:04 -05001003 dec_rt_prio_smp(rt_rq, prio, prev_prio);
1004}
Gregory Haskins1f11eb62008-06-04 15:04:05 -04001005
Gregory Haskins398a1532009-01-14 09:10:04 -05001006#else
1007
1008static inline void inc_rt_prio(struct rt_rq *rt_rq, int prio) {}
1009static inline void dec_rt_prio(struct rt_rq *rt_rq, int prio) {}
1010
1011#endif /* CONFIG_SMP || CONFIG_RT_GROUP_SCHED */
1012
Gregory Haskins73fe6aa2008-01-25 21:08:07 +01001013#ifdef CONFIG_RT_GROUP_SCHED
Gregory Haskins398a1532009-01-14 09:10:04 -05001014
1015static void
1016inc_rt_group(struct sched_rt_entity *rt_se, struct rt_rq *rt_rq)
1017{
Gregory Haskins73fe6aa2008-01-25 21:08:07 +01001018 if (rt_se_boosted(rt_se))
Steven Rostedt764a9d62008-01-25 21:08:04 +01001019 rt_rq->rt_nr_boosted++;
Peter Zijlstra052f1dc2008-02-13 15:45:40 +01001020
Peter Zijlstra23b0fdf2008-02-13 15:45:39 +01001021 if (rt_rq->tg)
1022 start_rt_bandwidth(&rt_rq->tg->rt_bandwidth);
Gregory Haskins398a1532009-01-14 09:10:04 -05001023}
1024
1025static void
1026dec_rt_group(struct sched_rt_entity *rt_se, struct rt_rq *rt_rq)
1027{
Peter Zijlstra23b0fdf2008-02-13 15:45:39 +01001028 if (rt_se_boosted(rt_se))
1029 rt_rq->rt_nr_boosted--;
1030
1031 WARN_ON(!rt_rq->rt_nr_running && rt_rq->rt_nr_boosted);
Gregory Haskins398a1532009-01-14 09:10:04 -05001032}
1033
1034#else /* CONFIG_RT_GROUP_SCHED */
1035
1036static void
1037inc_rt_group(struct sched_rt_entity *rt_se, struct rt_rq *rt_rq)
1038{
Ingo Molnarbb44e5d2007-07-09 18:51:58 +02001039 start_rt_bandwidth(&def_rt_bandwidth);
Gregory Haskins398a1532009-01-14 09:10:04 -05001040}
1041
1042static inline
1043void dec_rt_group(struct sched_rt_entity *rt_se, struct rt_rq *rt_rq) {}
1044
1045#endif /* CONFIG_RT_GROUP_SCHED */
1046
1047static inline
Kirill Tkhai22abdef2014-03-15 02:14:49 +04001048unsigned int rt_se_nr_running(struct sched_rt_entity *rt_se)
1049{
1050 struct rt_rq *group_rq = group_rt_rq(rt_se);
1051
1052 if (group_rq)
1053 return group_rq->rt_nr_running;
1054 else
1055 return 1;
1056}
1057
1058static inline
Gregory Haskins398a1532009-01-14 09:10:04 -05001059void inc_rt_tasks(struct sched_rt_entity *rt_se, struct rt_rq *rt_rq)
1060{
1061 int prio = rt_se_prio(rt_se);
1062
1063 WARN_ON(!rt_prio(prio));
Kirill Tkhai22abdef2014-03-15 02:14:49 +04001064 rt_rq->rt_nr_running += rt_se_nr_running(rt_se);
Gregory Haskins398a1532009-01-14 09:10:04 -05001065
1066 inc_rt_prio(rt_rq, prio);
1067 inc_rt_migration(rt_se, rt_rq);
1068 inc_rt_group(rt_se, rt_rq);
Ingo Molnarbb44e5d2007-07-09 18:51:58 +02001069}
1070
Peter Zijlstra23b0fdf2008-02-13 15:45:39 +01001071static inline
1072void dec_rt_tasks(struct sched_rt_entity *rt_se, struct rt_rq *rt_rq)
1073{
Ingo Molnarbb44e5d2007-07-09 18:51:58 +02001074 WARN_ON(!rt_prio(rt_se_prio(rt_se)));
Peter Zijlstra6f505b12008-01-25 21:08:30 +01001075 WARN_ON(!rt_rq->rt_nr_running);
Kirill Tkhai22abdef2014-03-15 02:14:49 +04001076 rt_rq->rt_nr_running -= rt_se_nr_running(rt_se);
Ingo Molnarbb44e5d2007-07-09 18:51:58 +02001077
Gregory Haskins398a1532009-01-14 09:10:04 -05001078 dec_rt_prio(rt_rq, rt_se_prio(rt_se));
1079 dec_rt_migration(rt_se, rt_rq);
1080 dec_rt_group(rt_se, rt_rq);
Ingo Molnarbb44e5d2007-07-09 18:51:58 +02001081}
1082
Thomas Gleixner37dad3f2010-01-20 20:59:01 +00001083static void __enqueue_rt_entity(struct sched_rt_entity *rt_se, bool head)
Ingo Molnarbb44e5d2007-07-09 18:51:58 +02001084{
Peter Zijlstra6f505b12008-01-25 21:08:30 +01001085 struct rt_rq *rt_rq = rt_rq_of_se(rt_se);
1086 struct rt_prio_array *array = &rt_rq->active;
1087 struct rt_rq *group_rq = group_rt_rq(rt_se);
Dmitry Adamushko20b63312008-06-11 00:58:30 +02001088 struct list_head *queue = array->queue + rt_se_prio(rt_se);
Ingo Molnarbb44e5d2007-07-09 18:51:58 +02001089
Peter Zijlstraad2a3f12008-06-19 09:06:57 +02001090 /*
1091 * Don't enqueue the group if its throttled, or when empty.
1092 * The latter is a consequence of the former when a child group
1093 * get throttled and the current group doesn't have any other
1094 * active members.
1095 */
1096 if (group_rq && (rt_rq_throttled(group_rq) || !group_rq->rt_nr_running))
Peter Zijlstra6f505b12008-01-25 21:08:30 +01001097 return;
Ingo Molnarbb44e5d2007-07-09 18:51:58 +02001098
Thomas Gleixner37dad3f2010-01-20 20:59:01 +00001099 if (head)
1100 list_add(&rt_se->run_list, queue);
1101 else
1102 list_add_tail(&rt_se->run_list, queue);
Peter Zijlstra6f505b12008-01-25 21:08:30 +01001103 __set_bit(rt_se_prio(rt_se), array->bitmap);
Peter Zijlstra78f2c7d2008-01-25 21:08:27 +01001104
Peter Zijlstra6f505b12008-01-25 21:08:30 +01001105 inc_rt_tasks(rt_se, rt_rq);
1106}
1107
Peter Zijlstraad2a3f12008-06-19 09:06:57 +02001108static void __dequeue_rt_entity(struct sched_rt_entity *rt_se)
Peter Zijlstra6f505b12008-01-25 21:08:30 +01001109{
1110 struct rt_rq *rt_rq = rt_rq_of_se(rt_se);
1111 struct rt_prio_array *array = &rt_rq->active;
1112
1113 list_del_init(&rt_se->run_list);
1114 if (list_empty(array->queue + rt_se_prio(rt_se)))
1115 __clear_bit(rt_se_prio(rt_se), array->bitmap);
1116
1117 dec_rt_tasks(rt_se, rt_rq);
1118}
1119
1120/*
1121 * Because the prio of an upper entry depends on the lower
1122 * entries, we must remove entries top - down.
Peter Zijlstra6f505b12008-01-25 21:08:30 +01001123 */
Peter Zijlstraad2a3f12008-06-19 09:06:57 +02001124static void dequeue_rt_stack(struct sched_rt_entity *rt_se)
Peter Zijlstra6f505b12008-01-25 21:08:30 +01001125{
Peter Zijlstraad2a3f12008-06-19 09:06:57 +02001126 struct sched_rt_entity *back = NULL;
Peter Zijlstra6f505b12008-01-25 21:08:30 +01001127
Peter Zijlstra58d6c2d2008-04-19 19:45:00 +02001128 for_each_sched_rt_entity(rt_se) {
1129 rt_se->back = back;
1130 back = rt_se;
1131 }
1132
1133 for (rt_se = back; rt_se; rt_se = rt_se->back) {
1134 if (on_rt_rq(rt_se))
Peter Zijlstraad2a3f12008-06-19 09:06:57 +02001135 __dequeue_rt_entity(rt_se);
1136 }
1137}
1138
Thomas Gleixner37dad3f2010-01-20 20:59:01 +00001139static void enqueue_rt_entity(struct sched_rt_entity *rt_se, bool head)
Peter Zijlstraad2a3f12008-06-19 09:06:57 +02001140{
1141 dequeue_rt_stack(rt_se);
1142 for_each_sched_rt_entity(rt_se)
Thomas Gleixner37dad3f2010-01-20 20:59:01 +00001143 __enqueue_rt_entity(rt_se, head);
Peter Zijlstraad2a3f12008-06-19 09:06:57 +02001144}
1145
1146static void dequeue_rt_entity(struct sched_rt_entity *rt_se)
1147{
1148 dequeue_rt_stack(rt_se);
1149
1150 for_each_sched_rt_entity(rt_se) {
1151 struct rt_rq *rt_rq = group_rt_rq(rt_se);
1152
1153 if (rt_rq && rt_rq->rt_nr_running)
Thomas Gleixner37dad3f2010-01-20 20:59:01 +00001154 __enqueue_rt_entity(rt_se, false);
Peter Zijlstra58d6c2d2008-04-19 19:45:00 +02001155 }
Ingo Molnarbb44e5d2007-07-09 18:51:58 +02001156}
1157
1158/*
1159 * Adding/removing a task to/from a priority array:
1160 */
Thomas Gleixnerea87bb72010-01-20 20:58:57 +00001161static void
Peter Zijlstra371fd7e2010-03-24 16:38:48 +01001162enqueue_task_rt(struct rq *rq, struct task_struct *p, int flags)
Peter Zijlstra6f505b12008-01-25 21:08:30 +01001163{
1164 struct sched_rt_entity *rt_se = &p->rt;
1165
Peter Zijlstra371fd7e2010-03-24 16:38:48 +01001166 if (flags & ENQUEUE_WAKEUP)
Peter Zijlstra6f505b12008-01-25 21:08:30 +01001167 rt_se->timeout = 0;
1168
Peter Zijlstra371fd7e2010-03-24 16:38:48 +01001169 enqueue_rt_entity(rt_se, flags & ENQUEUE_HEAD);
Peter Zijlstrac09595f2008-06-27 13:41:14 +02001170
Peter Zijlstra29baa742012-04-23 12:11:21 +02001171 if (!task_current(rq, p) && p->nr_cpus_allowed > 1)
Gregory Haskins917b6272008-12-29 09:39:53 -05001172 enqueue_pushable_task(rq, p);
Paul Turner953bfcd2011-07-21 09:43:27 -07001173
1174 inc_nr_running(rq);
Peter Zijlstra6f505b12008-01-25 21:08:30 +01001175}
1176
Peter Zijlstra371fd7e2010-03-24 16:38:48 +01001177static void dequeue_task_rt(struct rq *rq, struct task_struct *p, int flags)
Ingo Molnarbb44e5d2007-07-09 18:51:58 +02001178{
Peter Zijlstra6f505b12008-01-25 21:08:30 +01001179 struct sched_rt_entity *rt_se = &p->rt;
Ingo Molnarbb44e5d2007-07-09 18:51:58 +02001180
1181 update_curr_rt(rq);
Peter Zijlstraad2a3f12008-06-19 09:06:57 +02001182 dequeue_rt_entity(rt_se);
Peter Zijlstrac09595f2008-06-27 13:41:14 +02001183
Gregory Haskins917b6272008-12-29 09:39:53 -05001184 dequeue_pushable_task(rq, p);
Paul Turner953bfcd2011-07-21 09:43:27 -07001185
1186 dec_nr_running(rq);
Ingo Molnarbb44e5d2007-07-09 18:51:58 +02001187}
1188
1189/*
Richard Weinberger60686312011-11-12 18:07:57 +01001190 * Put task to the head or the end of the run list without the overhead of
1191 * dequeue followed by enqueue.
Ingo Molnarbb44e5d2007-07-09 18:51:58 +02001192 */
Dmitry Adamushko7ebefa82008-07-01 23:32:15 +02001193static void
1194requeue_rt_entity(struct rt_rq *rt_rq, struct sched_rt_entity *rt_se, int head)
Ingo Molnarbb44e5d2007-07-09 18:51:58 +02001195{
Ingo Molnar1cdad712008-06-19 09:09:15 +02001196 if (on_rt_rq(rt_se)) {
Dmitry Adamushko7ebefa82008-07-01 23:32:15 +02001197 struct rt_prio_array *array = &rt_rq->active;
1198 struct list_head *queue = array->queue + rt_se_prio(rt_se);
1199
1200 if (head)
1201 list_move(&rt_se->run_list, queue);
1202 else
1203 list_move_tail(&rt_se->run_list, queue);
Ingo Molnar1cdad712008-06-19 09:09:15 +02001204 }
Ingo Molnarbb44e5d2007-07-09 18:51:58 +02001205}
1206
Dmitry Adamushko7ebefa82008-07-01 23:32:15 +02001207static void requeue_task_rt(struct rq *rq, struct task_struct *p, int head)
Peter Zijlstra6f505b12008-01-25 21:08:30 +01001208{
1209 struct sched_rt_entity *rt_se = &p->rt;
1210 struct rt_rq *rt_rq;
1211
1212 for_each_sched_rt_entity(rt_se) {
1213 rt_rq = rt_rq_of_se(rt_se);
Dmitry Adamushko7ebefa82008-07-01 23:32:15 +02001214 requeue_rt_entity(rt_rq, rt_se, head);
Peter Zijlstra6f505b12008-01-25 21:08:30 +01001215 }
1216}
1217
1218static void yield_task_rt(struct rq *rq)
Ingo Molnarbb44e5d2007-07-09 18:51:58 +02001219{
Dmitry Adamushko7ebefa82008-07-01 23:32:15 +02001220 requeue_task_rt(rq, rq->curr, 0);
Ingo Molnarbb44e5d2007-07-09 18:51:58 +02001221}
1222
Gregory Haskinse7693a32008-01-25 21:08:09 +01001223#ifdef CONFIG_SMP
Gregory Haskins318e0892008-01-25 21:08:10 +01001224static int find_lowest_rq(struct task_struct *task);
1225
Peter Zijlstra0017d732010-03-24 18:34:10 +01001226static int
Peter Zijlstraac66f542013-10-07 11:29:16 +01001227select_task_rq_rt(struct task_struct *p, int cpu, int sd_flag, int flags)
Gregory Haskinse7693a32008-01-25 21:08:09 +01001228{
Peter Zijlstra7608dec2011-04-05 17:23:46 +02001229 struct task_struct *curr;
1230 struct rq *rq;
Steven Rostedtc37495f2011-06-16 21:55:22 -04001231
Peter Zijlstra29baa742012-04-23 12:11:21 +02001232 if (p->nr_cpus_allowed == 1)
Mike Galbraith76854c72011-11-22 15:18:24 +01001233 goto out;
1234
Steven Rostedtc37495f2011-06-16 21:55:22 -04001235 /* For anything but wake ups, just return the task_cpu */
1236 if (sd_flag != SD_BALANCE_WAKE && sd_flag != SD_BALANCE_FORK)
1237 goto out;
1238
Peter Zijlstra7608dec2011-04-05 17:23:46 +02001239 rq = cpu_rq(cpu);
1240
1241 rcu_read_lock();
1242 curr = ACCESS_ONCE(rq->curr); /* unlocked access */
1243
Gregory Haskins318e0892008-01-25 21:08:10 +01001244 /*
Peter Zijlstra7608dec2011-04-05 17:23:46 +02001245 * If the current task on @p's runqueue is an RT task, then
Steven Rostedte1f47d82008-01-25 21:08:12 +01001246 * try to see if we can wake this RT task up on another
1247 * runqueue. Otherwise simply start this RT task
1248 * on its current runqueue.
1249 *
Steven Rostedt43fa5462010-09-20 22:40:03 -04001250 * We want to avoid overloading runqueues. If the woken
1251 * task is a higher priority, then it will stay on this CPU
1252 * and the lower prio task should be moved to another CPU.
1253 * Even though this will probably make the lower prio task
1254 * lose its cache, we do not want to bounce a higher task
1255 * around just because it gave up its CPU, perhaps for a
1256 * lock?
1257 *
1258 * For equal prio tasks, we just let the scheduler sort it out.
Peter Zijlstra7608dec2011-04-05 17:23:46 +02001259 *
Gregory Haskins318e0892008-01-25 21:08:10 +01001260 * Otherwise, just let it ride on the affined RQ and the
1261 * post-schedule router will push the preempted task away
Peter Zijlstra7608dec2011-04-05 17:23:46 +02001262 *
1263 * This test is optimistic, if we get it wrong the load-balancer
1264 * will have to sort it out.
Gregory Haskins318e0892008-01-25 21:08:10 +01001265 */
Peter Zijlstra7608dec2011-04-05 17:23:46 +02001266 if (curr && unlikely(rt_task(curr)) &&
Peter Zijlstra29baa742012-04-23 12:11:21 +02001267 (curr->nr_cpus_allowed < 2 ||
Shawn Bohrer6bfa6872013-10-04 14:24:53 -05001268 curr->prio <= p->prio)) {
Peter Zijlstra7608dec2011-04-05 17:23:46 +02001269 int target = find_lowest_rq(p);
1270
1271 if (target != -1)
1272 cpu = target;
1273 }
1274 rcu_read_unlock();
1275
Steven Rostedtc37495f2011-06-16 21:55:22 -04001276out:
Peter Zijlstra7608dec2011-04-05 17:23:46 +02001277 return cpu;
Gregory Haskinse7693a32008-01-25 21:08:09 +01001278}
Dmitry Adamushko7ebefa82008-07-01 23:32:15 +02001279
1280static void check_preempt_equal_prio(struct rq *rq, struct task_struct *p)
1281{
Peter Zijlstra29baa742012-04-23 12:11:21 +02001282 if (rq->curr->nr_cpus_allowed == 1)
Dmitry Adamushko7ebefa82008-07-01 23:32:15 +02001283 return;
1284
Peter Zijlstra29baa742012-04-23 12:11:21 +02001285 if (p->nr_cpus_allowed != 1
Rusty Russell13b8bd02009-03-25 15:01:22 +10301286 && cpupri_find(&rq->rd->cpupri, p, NULL))
Dmitry Adamushko7ebefa82008-07-01 23:32:15 +02001287 return;
1288
Rusty Russell13b8bd02009-03-25 15:01:22 +10301289 if (!cpupri_find(&rq->rd->cpupri, rq->curr, NULL))
1290 return;
Dmitry Adamushko7ebefa82008-07-01 23:32:15 +02001291
1292 /*
1293 * There appears to be other cpus that can accept
1294 * current and none to run 'p', so lets reschedule
1295 * to try and push current away:
1296 */
1297 requeue_task_rt(rq, p, 1);
1298 resched_task(rq->curr);
1299}
1300
Gregory Haskinse7693a32008-01-25 21:08:09 +01001301#endif /* CONFIG_SMP */
1302
Ingo Molnarbb44e5d2007-07-09 18:51:58 +02001303/*
1304 * Preempt the current task with a newly woken task if needed:
1305 */
Peter Zijlstra7d478722009-09-14 19:55:44 +02001306static void check_preempt_curr_rt(struct rq *rq, struct task_struct *p, int flags)
Ingo Molnarbb44e5d2007-07-09 18:51:58 +02001307{
Gregory Haskins45c01e82008-05-12 21:20:41 +02001308 if (p->prio < rq->curr->prio) {
Ingo Molnarbb44e5d2007-07-09 18:51:58 +02001309 resched_task(rq->curr);
Gregory Haskins45c01e82008-05-12 21:20:41 +02001310 return;
1311 }
1312
1313#ifdef CONFIG_SMP
1314 /*
1315 * If:
1316 *
1317 * - the newly woken task is of equal priority to the current task
1318 * - the newly woken task is non-migratable while current is migratable
1319 * - current will be preempted on the next reschedule
1320 *
1321 * we should check to see if current can readily move to a different
1322 * cpu. If so, we will reschedule to allow the push logic to try
1323 * to move current somewhere else, making room for our non-migratable
1324 * task.
1325 */
Hillf Danton8dd0de82011-06-14 18:36:24 -04001326 if (p->prio == rq->curr->prio && !test_tsk_need_resched(rq->curr))
Dmitry Adamushko7ebefa82008-07-01 23:32:15 +02001327 check_preempt_equal_prio(rq, p);
Gregory Haskins45c01e82008-05-12 21:20:41 +02001328#endif
Ingo Molnarbb44e5d2007-07-09 18:51:58 +02001329}
1330
Peter Zijlstra6f505b12008-01-25 21:08:30 +01001331static struct sched_rt_entity *pick_next_rt_entity(struct rq *rq,
1332 struct rt_rq *rt_rq)
Ingo Molnarbb44e5d2007-07-09 18:51:58 +02001333{
Peter Zijlstra6f505b12008-01-25 21:08:30 +01001334 struct rt_prio_array *array = &rt_rq->active;
1335 struct sched_rt_entity *next = NULL;
Ingo Molnarbb44e5d2007-07-09 18:51:58 +02001336 struct list_head *queue;
1337 int idx;
1338
1339 idx = sched_find_first_bit(array->bitmap);
Peter Zijlstra6f505b12008-01-25 21:08:30 +01001340 BUG_ON(idx >= MAX_RT_PRIO);
Ingo Molnarbb44e5d2007-07-09 18:51:58 +02001341
1342 queue = array->queue + idx;
Peter Zijlstra6f505b12008-01-25 21:08:30 +01001343 next = list_entry(queue->next, struct sched_rt_entity, run_list);
Dmitry Adamushko326587b2008-01-25 21:08:34 +01001344
Ingo Molnarbb44e5d2007-07-09 18:51:58 +02001345 return next;
1346}
1347
Gregory Haskins917b6272008-12-29 09:39:53 -05001348static struct task_struct *_pick_next_task_rt(struct rq *rq)
Peter Zijlstra6f505b12008-01-25 21:08:30 +01001349{
1350 struct sched_rt_entity *rt_se;
1351 struct task_struct *p;
Peter Zijlstra606dba22012-02-11 06:05:00 +01001352 struct rt_rq *rt_rq = &rq->rt;
Peter Zijlstra6f505b12008-01-25 21:08:30 +01001353
1354 do {
1355 rt_se = pick_next_rt_entity(rq, rt_rq);
Dmitry Adamushko326587b2008-01-25 21:08:34 +01001356 BUG_ON(!rt_se);
Peter Zijlstra6f505b12008-01-25 21:08:30 +01001357 rt_rq = group_rt_rq(rt_se);
1358 } while (rt_rq);
1359
1360 p = rt_task_of(rt_se);
Frederic Weisbecker78becc22013-04-12 01:51:02 +02001361 p->se.exec_start = rq_clock_task(rq);
Gregory Haskins917b6272008-12-29 09:39:53 -05001362
1363 return p;
1364}
1365
Peter Zijlstra606dba22012-02-11 06:05:00 +01001366static struct task_struct *
1367pick_next_task_rt(struct rq *rq, struct task_struct *prev)
Gregory Haskins917b6272008-12-29 09:39:53 -05001368{
Peter Zijlstra606dba22012-02-11 06:05:00 +01001369 struct task_struct *p;
1370 struct rt_rq *rt_rq = &rq->rt;
1371
Peter Zijlstra37e117c2014-02-14 12:25:08 +01001372 if (need_pull_rt_task(rq, prev)) {
Peter Zijlstra38033c32014-01-23 20:32:21 +01001373 pull_rt_task(rq);
Peter Zijlstra37e117c2014-02-14 12:25:08 +01001374 /*
1375 * pull_rt_task() can drop (and re-acquire) rq->lock; this
Kirill Tkhaia1d9a322014-04-10 17:38:36 +04001376 * means a dl or stop task can slip in, in which case we need
1377 * to re-start task selection.
Peter Zijlstra37e117c2014-02-14 12:25:08 +01001378 */
Kirill Tkhaia1d9a322014-04-10 17:38:36 +04001379 if (unlikely((rq->stop && rq->stop->on_rq) ||
1380 rq->dl.dl_nr_running))
Peter Zijlstra37e117c2014-02-14 12:25:08 +01001381 return RETRY_TASK;
1382 }
Peter Zijlstra38033c32014-01-23 20:32:21 +01001383
Kirill Tkhai734ff2a2014-03-04 19:25:46 +04001384 /*
1385 * We may dequeue prev's rt_rq in put_prev_task().
1386 * So, we update time before rt_nr_running check.
1387 */
1388 if (prev->sched_class == &rt_sched_class)
1389 update_curr_rt(rq);
1390
Peter Zijlstra606dba22012-02-11 06:05:00 +01001391 if (!rt_rq->rt_nr_running)
1392 return NULL;
1393
1394 if (rt_rq_throttled(rt_rq))
1395 return NULL;
1396
Peter Zijlstra3f1d2a32014-02-12 10:49:30 +01001397 put_prev_task(rq, prev);
Peter Zijlstra606dba22012-02-11 06:05:00 +01001398
1399 p = _pick_next_task_rt(rq);
Gregory Haskins917b6272008-12-29 09:39:53 -05001400
1401 /* The running task is never eligible for pushing */
1402 if (p)
1403 dequeue_pushable_task(rq, p);
1404
Peter Zijlstradc877342014-02-12 15:47:29 +01001405 set_post_schedule(rq);
Gregory Haskins3f029d32009-07-29 11:08:47 -04001406
Peter Zijlstra6f505b12008-01-25 21:08:30 +01001407 return p;
1408}
1409
Ingo Molnar31ee5292007-08-09 11:16:49 +02001410static void put_prev_task_rt(struct rq *rq, struct task_struct *p)
Ingo Molnarbb44e5d2007-07-09 18:51:58 +02001411{
Ingo Molnarf1e14ef2007-08-09 11:16:48 +02001412 update_curr_rt(rq);
Gregory Haskins917b6272008-12-29 09:39:53 -05001413
1414 /*
1415 * The previous task needs to be made eligible for pushing
1416 * if it is still active
1417 */
Peter Zijlstra29baa742012-04-23 12:11:21 +02001418 if (on_rt_rq(&p->rt) && p->nr_cpus_allowed > 1)
Gregory Haskins917b6272008-12-29 09:39:53 -05001419 enqueue_pushable_task(rq, p);
Ingo Molnarbb44e5d2007-07-09 18:51:58 +02001420}
1421
Peter Williams681f3e62007-10-24 18:23:51 +02001422#ifdef CONFIG_SMP
Peter Zijlstra6f505b12008-01-25 21:08:30 +01001423
Steven Rostedte8fa1362008-01-25 21:08:05 +01001424/* Only try algorithms three times */
1425#define RT_MAX_TRIES 3
1426
Steven Rostedtf65eda42008-01-25 21:08:07 +01001427static int pick_rt_task(struct rq *rq, struct task_struct *p, int cpu)
1428{
1429 if (!task_running(rq, p) &&
Kirill Tkhai60334ca2013-01-31 18:56:17 +04001430 cpumask_test_cpu(cpu, tsk_cpus_allowed(p)))
Steven Rostedtf65eda42008-01-25 21:08:07 +01001431 return 1;
1432 return 0;
1433}
1434
Kirill Tkhaie23ee742013-06-07 15:37:43 -04001435/*
1436 * Return the highest pushable rq's task, which is suitable to be executed
1437 * on the cpu, NULL otherwise
1438 */
1439static struct task_struct *pick_highest_pushable_task(struct rq *rq, int cpu)
Steven Rostedte8fa1362008-01-25 21:08:05 +01001440{
Kirill Tkhaie23ee742013-06-07 15:37:43 -04001441 struct plist_head *head = &rq->rt.pushable_tasks;
1442 struct task_struct *p;
Steven Rostedte8fa1362008-01-25 21:08:05 +01001443
Kirill Tkhaie23ee742013-06-07 15:37:43 -04001444 if (!has_pushable_tasks(rq))
1445 return NULL;
Peter Zijlstra3d074672010-03-10 17:07:24 +01001446
Kirill Tkhaie23ee742013-06-07 15:37:43 -04001447 plist_for_each_entry(p, head, pushable_tasks) {
1448 if (pick_rt_task(rq, p, cpu))
1449 return p;
Steven Rostedte8fa1362008-01-25 21:08:05 +01001450 }
1451
Kirill Tkhaie23ee742013-06-07 15:37:43 -04001452 return NULL;
Steven Rostedte8fa1362008-01-25 21:08:05 +01001453}
1454
Rusty Russell0e3900e2008-11-25 02:35:13 +10301455static DEFINE_PER_CPU(cpumask_var_t, local_cpu_mask);
Steven Rostedte8fa1362008-01-25 21:08:05 +01001456
Gregory Haskins6e1254d2008-01-25 21:08:11 +01001457static int find_lowest_rq(struct task_struct *task)
1458{
1459 struct sched_domain *sd;
Rusty Russell96f874e2008-11-25 02:35:14 +10301460 struct cpumask *lowest_mask = __get_cpu_var(local_cpu_mask);
Gregory Haskins6e1254d2008-01-25 21:08:11 +01001461 int this_cpu = smp_processor_id();
1462 int cpu = task_cpu(task);
1463
Steven Rostedt0da938c2011-06-14 18:36:25 -04001464 /* Make sure the mask is initialized first */
1465 if (unlikely(!lowest_mask))
1466 return -1;
1467
Peter Zijlstra29baa742012-04-23 12:11:21 +02001468 if (task->nr_cpus_allowed == 1)
Gregory Haskins6e0534f2008-05-12 21:21:01 +02001469 return -1; /* No other targets possible */
1470
1471 if (!cpupri_find(&task_rq(task)->rd->cpupri, task, lowest_mask))
Gregory Haskins06f90db2008-01-25 21:08:13 +01001472 return -1; /* No targets found */
1473
1474 /*
Gregory Haskins6e1254d2008-01-25 21:08:11 +01001475 * At this point we have built a mask of cpus representing the
1476 * lowest priority tasks in the system. Now we want to elect
1477 * the best one based on our affinity and topology.
1478 *
1479 * We prioritize the last cpu that the task executed on since
1480 * it is most likely cache-hot in that location.
1481 */
Rusty Russell96f874e2008-11-25 02:35:14 +10301482 if (cpumask_test_cpu(cpu, lowest_mask))
Gregory Haskins6e1254d2008-01-25 21:08:11 +01001483 return cpu;
1484
1485 /*
1486 * Otherwise, we consult the sched_domains span maps to figure
1487 * out which cpu is logically closest to our hot cache data.
1488 */
Rusty Russelle2c88062009-11-03 14:53:15 +10301489 if (!cpumask_test_cpu(this_cpu, lowest_mask))
1490 this_cpu = -1; /* Skip this_cpu opt if not among lowest */
Gregory Haskins6e1254d2008-01-25 21:08:11 +01001491
Xiaotian Fengcd4ae6a2011-04-22 18:53:54 +08001492 rcu_read_lock();
Rusty Russelle2c88062009-11-03 14:53:15 +10301493 for_each_domain(cpu, sd) {
1494 if (sd->flags & SD_WAKE_AFFINE) {
1495 int best_cpu;
Gregory Haskins6e1254d2008-01-25 21:08:11 +01001496
Rusty Russelle2c88062009-11-03 14:53:15 +10301497 /*
1498 * "this_cpu" is cheaper to preempt than a
1499 * remote processor.
1500 */
1501 if (this_cpu != -1 &&
Xiaotian Fengcd4ae6a2011-04-22 18:53:54 +08001502 cpumask_test_cpu(this_cpu, sched_domain_span(sd))) {
1503 rcu_read_unlock();
Rusty Russelle2c88062009-11-03 14:53:15 +10301504 return this_cpu;
Xiaotian Fengcd4ae6a2011-04-22 18:53:54 +08001505 }
Gregory Haskins6e1254d2008-01-25 21:08:11 +01001506
Rusty Russelle2c88062009-11-03 14:53:15 +10301507 best_cpu = cpumask_first_and(lowest_mask,
1508 sched_domain_span(sd));
Xiaotian Fengcd4ae6a2011-04-22 18:53:54 +08001509 if (best_cpu < nr_cpu_ids) {
1510 rcu_read_unlock();
Rusty Russelle2c88062009-11-03 14:53:15 +10301511 return best_cpu;
Xiaotian Fengcd4ae6a2011-04-22 18:53:54 +08001512 }
Gregory Haskins6e1254d2008-01-25 21:08:11 +01001513 }
1514 }
Xiaotian Fengcd4ae6a2011-04-22 18:53:54 +08001515 rcu_read_unlock();
Gregory Haskins6e1254d2008-01-25 21:08:11 +01001516
1517 /*
1518 * And finally, if there were no matches within the domains
1519 * just give the caller *something* to work with from the compatible
1520 * locations.
1521 */
Rusty Russelle2c88062009-11-03 14:53:15 +10301522 if (this_cpu != -1)
1523 return this_cpu;
1524
1525 cpu = cpumask_any(lowest_mask);
1526 if (cpu < nr_cpu_ids)
1527 return cpu;
1528 return -1;
Gregory Haskins07b40322008-01-25 21:08:10 +01001529}
1530
Steven Rostedte8fa1362008-01-25 21:08:05 +01001531/* Will lock the rq it finds */
Ingo Molnar4df64c02008-01-25 21:08:15 +01001532static struct rq *find_lock_lowest_rq(struct task_struct *task, struct rq *rq)
Steven Rostedte8fa1362008-01-25 21:08:05 +01001533{
1534 struct rq *lowest_rq = NULL;
Steven Rostedte8fa1362008-01-25 21:08:05 +01001535 int tries;
Ingo Molnar4df64c02008-01-25 21:08:15 +01001536 int cpu;
Steven Rostedte8fa1362008-01-25 21:08:05 +01001537
1538 for (tries = 0; tries < RT_MAX_TRIES; tries++) {
Gregory Haskins07b40322008-01-25 21:08:10 +01001539 cpu = find_lowest_rq(task);
Steven Rostedte8fa1362008-01-25 21:08:05 +01001540
Gregory Haskins2de0b462008-01-25 21:08:10 +01001541 if ((cpu == -1) || (cpu == rq->cpu))
Steven Rostedte8fa1362008-01-25 21:08:05 +01001542 break;
1543
Gregory Haskins07b40322008-01-25 21:08:10 +01001544 lowest_rq = cpu_rq(cpu);
1545
Steven Rostedte8fa1362008-01-25 21:08:05 +01001546 /* if the prio of this runqueue changed, try again */
Gregory Haskins07b40322008-01-25 21:08:10 +01001547 if (double_lock_balance(rq, lowest_rq)) {
Steven Rostedte8fa1362008-01-25 21:08:05 +01001548 /*
1549 * We had to unlock the run queue. In
1550 * the mean time, task could have
1551 * migrated already or had its affinity changed.
1552 * Also make sure that it wasn't scheduled on its rq.
1553 */
Gregory Haskins07b40322008-01-25 21:08:10 +01001554 if (unlikely(task_rq(task) != rq ||
Rusty Russell96f874e2008-11-25 02:35:14 +10301555 !cpumask_test_cpu(lowest_rq->cpu,
Peter Zijlstrafa17b502011-06-16 12:23:22 +02001556 tsk_cpus_allowed(task)) ||
Gregory Haskins07b40322008-01-25 21:08:10 +01001557 task_running(rq, task) ||
Peter Zijlstrafd2f4412011-04-05 17:23:44 +02001558 !task->on_rq)) {
Ingo Molnar4df64c02008-01-25 21:08:15 +01001559
Peter Zijlstra7f1b4392012-05-17 21:19:46 +02001560 double_unlock_balance(rq, lowest_rq);
Steven Rostedte8fa1362008-01-25 21:08:05 +01001561 lowest_rq = NULL;
1562 break;
1563 }
1564 }
1565
1566 /* If this rq is still suitable use it. */
Gregory Haskinse864c492008-12-29 09:39:49 -05001567 if (lowest_rq->rt.highest_prio.curr > task->prio)
Steven Rostedte8fa1362008-01-25 21:08:05 +01001568 break;
1569
1570 /* try again */
Peter Zijlstra1b12bbc2008-08-11 09:30:22 +02001571 double_unlock_balance(rq, lowest_rq);
Steven Rostedte8fa1362008-01-25 21:08:05 +01001572 lowest_rq = NULL;
1573 }
1574
1575 return lowest_rq;
1576}
1577
Gregory Haskins917b6272008-12-29 09:39:53 -05001578static struct task_struct *pick_next_pushable_task(struct rq *rq)
1579{
1580 struct task_struct *p;
1581
1582 if (!has_pushable_tasks(rq))
1583 return NULL;
1584
1585 p = plist_first_entry(&rq->rt.pushable_tasks,
1586 struct task_struct, pushable_tasks);
1587
1588 BUG_ON(rq->cpu != task_cpu(p));
1589 BUG_ON(task_current(rq, p));
Peter Zijlstra29baa742012-04-23 12:11:21 +02001590 BUG_ON(p->nr_cpus_allowed <= 1);
Gregory Haskins917b6272008-12-29 09:39:53 -05001591
Peter Zijlstrafd2f4412011-04-05 17:23:44 +02001592 BUG_ON(!p->on_rq);
Gregory Haskins917b6272008-12-29 09:39:53 -05001593 BUG_ON(!rt_task(p));
1594
1595 return p;
1596}
1597
Steven Rostedte8fa1362008-01-25 21:08:05 +01001598/*
1599 * If the current CPU has more than one RT task, see if the non
1600 * running task can migrate over to a CPU that is running a task
1601 * of lesser priority.
1602 */
Gregory Haskins697f0a42008-01-25 21:08:09 +01001603static int push_rt_task(struct rq *rq)
Steven Rostedte8fa1362008-01-25 21:08:05 +01001604{
1605 struct task_struct *next_task;
1606 struct rq *lowest_rq;
Hillf Danton311e8002011-06-16 21:55:20 -04001607 int ret = 0;
Steven Rostedte8fa1362008-01-25 21:08:05 +01001608
Gregory Haskinsa22d7fc2008-01-25 21:08:12 +01001609 if (!rq->rt.overloaded)
1610 return 0;
1611
Gregory Haskins917b6272008-12-29 09:39:53 -05001612 next_task = pick_next_pushable_task(rq);
Steven Rostedte8fa1362008-01-25 21:08:05 +01001613 if (!next_task)
1614 return 0;
1615
Peter Zijlstra49246272010-10-17 21:46:10 +02001616retry:
Gregory Haskins697f0a42008-01-25 21:08:09 +01001617 if (unlikely(next_task == rq->curr)) {
Steven Rostedtf65eda42008-01-25 21:08:07 +01001618 WARN_ON(1);
Steven Rostedte8fa1362008-01-25 21:08:05 +01001619 return 0;
Steven Rostedtf65eda42008-01-25 21:08:07 +01001620 }
Steven Rostedte8fa1362008-01-25 21:08:05 +01001621
1622 /*
1623 * It's possible that the next_task slipped in of
1624 * higher priority than current. If that's the case
1625 * just reschedule current.
1626 */
Gregory Haskins697f0a42008-01-25 21:08:09 +01001627 if (unlikely(next_task->prio < rq->curr->prio)) {
1628 resched_task(rq->curr);
Steven Rostedte8fa1362008-01-25 21:08:05 +01001629 return 0;
1630 }
1631
Gregory Haskins697f0a42008-01-25 21:08:09 +01001632 /* We might release rq lock */
Steven Rostedte8fa1362008-01-25 21:08:05 +01001633 get_task_struct(next_task);
1634
1635 /* find_lock_lowest_rq locks the rq if found */
Gregory Haskins697f0a42008-01-25 21:08:09 +01001636 lowest_rq = find_lock_lowest_rq(next_task, rq);
Steven Rostedte8fa1362008-01-25 21:08:05 +01001637 if (!lowest_rq) {
1638 struct task_struct *task;
1639 /*
Hillf Danton311e8002011-06-16 21:55:20 -04001640 * find_lock_lowest_rq releases rq->lock
Gregory Haskins15635132008-12-29 09:39:53 -05001641 * so it is possible that next_task has migrated.
1642 *
1643 * We need to make sure that the task is still on the same
1644 * run-queue and is also still the next task eligible for
1645 * pushing.
Steven Rostedte8fa1362008-01-25 21:08:05 +01001646 */
Gregory Haskins917b6272008-12-29 09:39:53 -05001647 task = pick_next_pushable_task(rq);
Gregory Haskins15635132008-12-29 09:39:53 -05001648 if (task_cpu(next_task) == rq->cpu && task == next_task) {
1649 /*
Hillf Danton311e8002011-06-16 21:55:20 -04001650 * The task hasn't migrated, and is still the next
1651 * eligible task, but we failed to find a run-queue
1652 * to push it to. Do not retry in this case, since
1653 * other cpus will pull from us when ready.
Gregory Haskins15635132008-12-29 09:39:53 -05001654 */
Gregory Haskins15635132008-12-29 09:39:53 -05001655 goto out;
Steven Rostedte8fa1362008-01-25 21:08:05 +01001656 }
Gregory Haskins917b6272008-12-29 09:39:53 -05001657
Gregory Haskins15635132008-12-29 09:39:53 -05001658 if (!task)
1659 /* No more tasks, just exit */
1660 goto out;
1661
Gregory Haskins917b6272008-12-29 09:39:53 -05001662 /*
Gregory Haskins15635132008-12-29 09:39:53 -05001663 * Something has shifted, try again.
Gregory Haskins917b6272008-12-29 09:39:53 -05001664 */
Gregory Haskins15635132008-12-29 09:39:53 -05001665 put_task_struct(next_task);
1666 next_task = task;
1667 goto retry;
Steven Rostedte8fa1362008-01-25 21:08:05 +01001668 }
1669
Gregory Haskins697f0a42008-01-25 21:08:09 +01001670 deactivate_task(rq, next_task, 0);
Steven Rostedte8fa1362008-01-25 21:08:05 +01001671 set_task_cpu(next_task, lowest_rq->cpu);
1672 activate_task(lowest_rq, next_task, 0);
Hillf Danton311e8002011-06-16 21:55:20 -04001673 ret = 1;
Steven Rostedte8fa1362008-01-25 21:08:05 +01001674
1675 resched_task(lowest_rq->curr);
1676
Peter Zijlstra1b12bbc2008-08-11 09:30:22 +02001677 double_unlock_balance(rq, lowest_rq);
Steven Rostedte8fa1362008-01-25 21:08:05 +01001678
Steven Rostedte8fa1362008-01-25 21:08:05 +01001679out:
1680 put_task_struct(next_task);
1681
Hillf Danton311e8002011-06-16 21:55:20 -04001682 return ret;
Steven Rostedte8fa1362008-01-25 21:08:05 +01001683}
1684
Steven Rostedte8fa1362008-01-25 21:08:05 +01001685static void push_rt_tasks(struct rq *rq)
1686{
1687 /* push_rt_task will return true if it moved an RT */
1688 while (push_rt_task(rq))
1689 ;
1690}
1691
Steven Rostedtf65eda42008-01-25 21:08:07 +01001692static int pull_rt_task(struct rq *this_rq)
1693{
Ingo Molnar80bf3172008-01-25 21:08:17 +01001694 int this_cpu = this_rq->cpu, ret = 0, cpu;
Gregory Haskinsa8728942008-12-29 09:39:49 -05001695 struct task_struct *p;
Steven Rostedtf65eda42008-01-25 21:08:07 +01001696 struct rq *src_rq;
Steven Rostedtf65eda42008-01-25 21:08:07 +01001697
Gregory Haskins637f5082008-01-25 21:08:18 +01001698 if (likely(!rt_overloaded(this_rq)))
Steven Rostedtf65eda42008-01-25 21:08:07 +01001699 return 0;
1700
Peter Zijlstra7c3f2ab2013-10-15 12:35:07 +02001701 /*
1702 * Match the barrier from rt_set_overloaded; this guarantees that if we
1703 * see overloaded we must also see the rto_mask bit.
1704 */
1705 smp_rmb();
1706
Rusty Russellc6c49272008-11-25 02:35:05 +10301707 for_each_cpu(cpu, this_rq->rd->rto_mask) {
Steven Rostedtf65eda42008-01-25 21:08:07 +01001708 if (this_cpu == cpu)
1709 continue;
1710
1711 src_rq = cpu_rq(cpu);
Gregory Haskins74ab8e42008-12-29 09:39:50 -05001712
1713 /*
1714 * Don't bother taking the src_rq->lock if the next highest
1715 * task is known to be lower-priority than our current task.
1716 * This may look racy, but if this value is about to go
1717 * logically higher, the src_rq will push this task away.
1718 * And if its going logically lower, we do not care
1719 */
1720 if (src_rq->rt.highest_prio.next >=
1721 this_rq->rt.highest_prio.curr)
1722 continue;
1723
Steven Rostedtf65eda42008-01-25 21:08:07 +01001724 /*
1725 * We can potentially drop this_rq's lock in
1726 * double_lock_balance, and another CPU could
Gregory Haskinsa8728942008-12-29 09:39:49 -05001727 * alter this_rq
Steven Rostedtf65eda42008-01-25 21:08:07 +01001728 */
Gregory Haskinsa8728942008-12-29 09:39:49 -05001729 double_lock_balance(this_rq, src_rq);
Steven Rostedtf65eda42008-01-25 21:08:07 +01001730
1731 /*
Kirill Tkhaie23ee742013-06-07 15:37:43 -04001732 * We can pull only a task, which is pushable
1733 * on its rq, and no others.
Steven Rostedtf65eda42008-01-25 21:08:07 +01001734 */
Kirill Tkhaie23ee742013-06-07 15:37:43 -04001735 p = pick_highest_pushable_task(src_rq, this_cpu);
Steven Rostedtf65eda42008-01-25 21:08:07 +01001736
1737 /*
1738 * Do we have an RT task that preempts
1739 * the to-be-scheduled task?
1740 */
Gregory Haskinsa8728942008-12-29 09:39:49 -05001741 if (p && (p->prio < this_rq->rt.highest_prio.curr)) {
Steven Rostedtf65eda42008-01-25 21:08:07 +01001742 WARN_ON(p == src_rq->curr);
Peter Zijlstrafd2f4412011-04-05 17:23:44 +02001743 WARN_ON(!p->on_rq);
Steven Rostedtf65eda42008-01-25 21:08:07 +01001744
1745 /*
1746 * There's a chance that p is higher in priority
1747 * than what's currently running on its cpu.
1748 * This is just that p is wakeing up and hasn't
1749 * had a chance to schedule. We only pull
1750 * p if it is lower in priority than the
Gregory Haskinsa8728942008-12-29 09:39:49 -05001751 * current task on the run queue
Steven Rostedtf65eda42008-01-25 21:08:07 +01001752 */
Gregory Haskinsa8728942008-12-29 09:39:49 -05001753 if (p->prio < src_rq->curr->prio)
Mike Galbraith614ee1f2008-01-25 21:08:30 +01001754 goto skip;
Steven Rostedtf65eda42008-01-25 21:08:07 +01001755
1756 ret = 1;
1757
1758 deactivate_task(src_rq, p, 0);
1759 set_task_cpu(p, this_cpu);
1760 activate_task(this_rq, p, 0);
1761 /*
1762 * We continue with the search, just in
1763 * case there's an even higher prio task
Lucas De Marchi25985ed2011-03-30 22:57:33 -03001764 * in another runqueue. (low likelihood
Steven Rostedtf65eda42008-01-25 21:08:07 +01001765 * but possible)
Steven Rostedtf65eda42008-01-25 21:08:07 +01001766 */
Steven Rostedtf65eda42008-01-25 21:08:07 +01001767 }
Peter Zijlstra49246272010-10-17 21:46:10 +02001768skip:
Peter Zijlstra1b12bbc2008-08-11 09:30:22 +02001769 double_unlock_balance(this_rq, src_rq);
Steven Rostedtf65eda42008-01-25 21:08:07 +01001770 }
1771
1772 return ret;
1773}
1774
Steven Rostedt9a897c52008-01-25 21:08:22 +01001775static void post_schedule_rt(struct rq *rq)
Steven Rostedte8fa1362008-01-25 21:08:05 +01001776{
Gregory Haskins967fc042008-12-29 09:39:52 -05001777 push_rt_tasks(rq);
Steven Rostedte8fa1362008-01-25 21:08:05 +01001778}
1779
Gregory Haskins8ae121a2008-04-23 07:13:29 -04001780/*
1781 * If we are not running and we are not going to reschedule soon, we should
1782 * try to push tasks away now
1783 */
Peter Zijlstraefbbd052009-12-16 18:04:40 +01001784static void task_woken_rt(struct rq *rq, struct task_struct *p)
Steven Rostedt4642daf2008-01-25 21:08:07 +01001785{
Steven Rostedt9a897c52008-01-25 21:08:22 +01001786 if (!task_running(rq, p) &&
Gregory Haskins8ae121a2008-04-23 07:13:29 -04001787 !test_tsk_need_resched(rq->curr) &&
Gregory Haskins917b6272008-12-29 09:39:53 -05001788 has_pushable_tasks(rq) &&
Peter Zijlstra29baa742012-04-23 12:11:21 +02001789 p->nr_cpus_allowed > 1 &&
Juri Lelli1baca4c2013-11-07 14:43:38 +01001790 (dl_task(rq->curr) || rt_task(rq->curr)) &&
Peter Zijlstra29baa742012-04-23 12:11:21 +02001791 (rq->curr->nr_cpus_allowed < 2 ||
Shawn Bohrer3be209a2011-09-12 09:28:04 -05001792 rq->curr->prio <= p->prio))
Steven Rostedt4642daf2008-01-25 21:08:07 +01001793 push_rt_tasks(rq);
1794}
1795
Mike Traviscd8ba7c2008-03-26 14:23:49 -07001796static void set_cpus_allowed_rt(struct task_struct *p,
Rusty Russell96f874e2008-11-25 02:35:14 +10301797 const struct cpumask *new_mask)
Gregory Haskins73fe6aa2008-01-25 21:08:07 +01001798{
Kirill Tkhai8d3d5ad2012-04-11 09:06:04 +04001799 struct rq *rq;
1800 int weight;
Gregory Haskins73fe6aa2008-01-25 21:08:07 +01001801
1802 BUG_ON(!rt_task(p));
1803
Kirill Tkhai8d3d5ad2012-04-11 09:06:04 +04001804 if (!p->on_rq)
1805 return;
1806
1807 weight = cpumask_weight(new_mask);
1808
Gregory Haskins73fe6aa2008-01-25 21:08:07 +01001809 /*
Kirill Tkhai8d3d5ad2012-04-11 09:06:04 +04001810 * Only update if the process changes its state from whether it
1811 * can migrate or not.
Gregory Haskins73fe6aa2008-01-25 21:08:07 +01001812 */
Peter Zijlstra29baa742012-04-23 12:11:21 +02001813 if ((p->nr_cpus_allowed > 1) == (weight > 1))
Kirill Tkhai8d3d5ad2012-04-11 09:06:04 +04001814 return;
Gregory Haskins73fe6aa2008-01-25 21:08:07 +01001815
Kirill Tkhai8d3d5ad2012-04-11 09:06:04 +04001816 rq = task_rq(p);
Gregory Haskins917b6272008-12-29 09:39:53 -05001817
Kirill Tkhai8d3d5ad2012-04-11 09:06:04 +04001818 /*
1819 * The process used to be able to migrate OR it can now migrate
1820 */
1821 if (weight <= 1) {
1822 if (!task_current(rq, p))
1823 dequeue_pushable_task(rq, p);
1824 BUG_ON(!rq->rt.rt_nr_migratory);
1825 rq->rt.rt_nr_migratory--;
1826 } else {
1827 if (!task_current(rq, p))
1828 enqueue_pushable_task(rq, p);
1829 rq->rt.rt_nr_migratory++;
Gregory Haskins73fe6aa2008-01-25 21:08:07 +01001830 }
Kirill Tkhai8d3d5ad2012-04-11 09:06:04 +04001831
1832 update_rt_migration(&rq->rt);
Gregory Haskins73fe6aa2008-01-25 21:08:07 +01001833}
Ingo Molnardeeeccd2008-01-25 21:08:15 +01001834
Ingo Molnarbdd7c812008-01-25 21:08:18 +01001835/* Assumes rq->lock is held */
Gregory Haskins1f11eb62008-06-04 15:04:05 -04001836static void rq_online_rt(struct rq *rq)
Ingo Molnarbdd7c812008-01-25 21:08:18 +01001837{
1838 if (rq->rt.overloaded)
1839 rt_set_overload(rq);
Gregory Haskins6e0534f2008-05-12 21:21:01 +02001840
Peter Zijlstra7def2be2008-06-05 14:49:58 +02001841 __enable_runtime(rq);
1842
Gregory Haskinse864c492008-12-29 09:39:49 -05001843 cpupri_set(&rq->rd->cpupri, rq->cpu, rq->rt.highest_prio.curr);
Ingo Molnarbdd7c812008-01-25 21:08:18 +01001844}
1845
1846/* Assumes rq->lock is held */
Gregory Haskins1f11eb62008-06-04 15:04:05 -04001847static void rq_offline_rt(struct rq *rq)
Ingo Molnarbdd7c812008-01-25 21:08:18 +01001848{
1849 if (rq->rt.overloaded)
1850 rt_clear_overload(rq);
Gregory Haskins6e0534f2008-05-12 21:21:01 +02001851
Peter Zijlstra7def2be2008-06-05 14:49:58 +02001852 __disable_runtime(rq);
1853
Gregory Haskins6e0534f2008-05-12 21:21:01 +02001854 cpupri_set(&rq->rd->cpupri, rq->cpu, CPUPRI_INVALID);
Ingo Molnarbdd7c812008-01-25 21:08:18 +01001855}
Steven Rostedtcb469842008-01-25 21:08:22 +01001856
1857/*
1858 * When switch from the rt queue, we bring ourselves to a position
1859 * that we might want to pull RT tasks from other runqueues.
1860 */
Peter Zijlstrada7a7352011-01-17 17:03:27 +01001861static void switched_from_rt(struct rq *rq, struct task_struct *p)
Steven Rostedtcb469842008-01-25 21:08:22 +01001862{
1863 /*
1864 * If there are other RT tasks then we will reschedule
1865 * and the scheduling of the other RT tasks will handle
1866 * the balancing. But if we are the last RT task
1867 * we may need to handle the pulling of RT tasks
1868 * now.
1869 */
Kirill Tkhai1158ddb2012-11-23 00:02:15 +04001870 if (!p->on_rq || rq->rt.rt_nr_running)
1871 return;
1872
1873 if (pull_rt_task(rq))
1874 resched_task(rq->curr);
Steven Rostedtcb469842008-01-25 21:08:22 +01001875}
Rusty Russell3d8cbdf2008-11-25 09:58:41 +10301876
Li Zefan11c785b2014-02-08 14:17:45 +08001877void __init init_sched_rt_class(void)
Rusty Russell3d8cbdf2008-11-25 09:58:41 +10301878{
1879 unsigned int i;
1880
Peter Zijlstra029632f2011-10-25 10:00:11 +02001881 for_each_possible_cpu(i) {
Yinghai Lueaa95842009-06-06 14:51:36 -07001882 zalloc_cpumask_var_node(&per_cpu(local_cpu_mask, i),
Mike Travis6ca09df2008-12-31 18:08:45 -08001883 GFP_KERNEL, cpu_to_node(i));
Peter Zijlstra029632f2011-10-25 10:00:11 +02001884 }
Rusty Russell3d8cbdf2008-11-25 09:58:41 +10301885}
Steven Rostedte8fa1362008-01-25 21:08:05 +01001886#endif /* CONFIG_SMP */
Ingo Molnarbb44e5d2007-07-09 18:51:58 +02001887
Steven Rostedtcb469842008-01-25 21:08:22 +01001888/*
1889 * When switching a task to RT, we may overload the runqueue
1890 * with RT tasks. In this case we try to push them off to
1891 * other runqueues.
1892 */
Peter Zijlstrada7a7352011-01-17 17:03:27 +01001893static void switched_to_rt(struct rq *rq, struct task_struct *p)
Steven Rostedtcb469842008-01-25 21:08:22 +01001894{
1895 int check_resched = 1;
1896
1897 /*
1898 * If we are already running, then there's nothing
1899 * that needs to be done. But if we are not running
1900 * we may need to preempt the current running task.
1901 * If that current running task is also an RT task
1902 * then see if we can move to another run queue.
1903 */
Peter Zijlstrafd2f4412011-04-05 17:23:44 +02001904 if (p->on_rq && rq->curr != p) {
Steven Rostedtcb469842008-01-25 21:08:22 +01001905#ifdef CONFIG_SMP
Kirill V Tkhai10447912014-03-12 06:18:33 -04001906 if (p->nr_cpus_allowed > 1 && rq->rt.overloaded &&
Steven Rostedtcb469842008-01-25 21:08:22 +01001907 /* Don't resched if we changed runqueues */
Kirill V Tkhai10447912014-03-12 06:18:33 -04001908 push_rt_task(rq) && rq != task_rq(p))
Steven Rostedtcb469842008-01-25 21:08:22 +01001909 check_resched = 0;
1910#endif /* CONFIG_SMP */
1911 if (check_resched && p->prio < rq->curr->prio)
1912 resched_task(rq->curr);
1913 }
1914}
1915
1916/*
1917 * Priority of the task has changed. This may cause
1918 * us to initiate a push or pull.
1919 */
Peter Zijlstrada7a7352011-01-17 17:03:27 +01001920static void
1921prio_changed_rt(struct rq *rq, struct task_struct *p, int oldprio)
Steven Rostedtcb469842008-01-25 21:08:22 +01001922{
Peter Zijlstrafd2f4412011-04-05 17:23:44 +02001923 if (!p->on_rq)
Peter Zijlstrada7a7352011-01-17 17:03:27 +01001924 return;
1925
1926 if (rq->curr == p) {
Steven Rostedtcb469842008-01-25 21:08:22 +01001927#ifdef CONFIG_SMP
1928 /*
1929 * If our priority decreases while running, we
1930 * may need to pull tasks to this runqueue.
1931 */
1932 if (oldprio < p->prio)
1933 pull_rt_task(rq);
1934 /*
1935 * If there's a higher priority task waiting to run
Steven Rostedt6fa46fa2008-03-05 10:00:12 -05001936 * then reschedule. Note, the above pull_rt_task
1937 * can release the rq lock and p could migrate.
1938 * Only reschedule if p is still on the same runqueue.
Steven Rostedtcb469842008-01-25 21:08:22 +01001939 */
Gregory Haskinse864c492008-12-29 09:39:49 -05001940 if (p->prio > rq->rt.highest_prio.curr && rq->curr == p)
Steven Rostedtcb469842008-01-25 21:08:22 +01001941 resched_task(p);
1942#else
1943 /* For UP simply resched on drop of prio */
1944 if (oldprio < p->prio)
1945 resched_task(p);
1946#endif /* CONFIG_SMP */
1947 } else {
1948 /*
1949 * This task is not running, but if it is
1950 * greater than the current running task
1951 * then reschedule.
1952 */
1953 if (p->prio < rq->curr->prio)
1954 resched_task(rq->curr);
1955 }
1956}
1957
Peter Zijlstra78f2c7d2008-01-25 21:08:27 +01001958static void watchdog(struct rq *rq, struct task_struct *p)
1959{
1960 unsigned long soft, hard;
1961
Jiri Slaby78d7d402010-03-05 13:42:54 -08001962 /* max may change after cur was read, this will be fixed next tick */
1963 soft = task_rlimit(p, RLIMIT_RTTIME);
1964 hard = task_rlimit_max(p, RLIMIT_RTTIME);
Peter Zijlstra78f2c7d2008-01-25 21:08:27 +01001965
1966 if (soft != RLIM_INFINITY) {
1967 unsigned long next;
1968
Ying Xue57d2aa02012-07-17 15:03:43 +08001969 if (p->rt.watchdog_stamp != jiffies) {
1970 p->rt.timeout++;
1971 p->rt.watchdog_stamp = jiffies;
1972 }
1973
Peter Zijlstra78f2c7d2008-01-25 21:08:27 +01001974 next = DIV_ROUND_UP(min(soft, hard), USEC_PER_SEC/HZ);
Peter Zijlstra5a52dd52008-01-25 21:08:32 +01001975 if (p->rt.timeout > next)
Frank Mayharf06febc2008-09-12 09:54:39 -07001976 p->cputime_expires.sched_exp = p->se.sum_exec_runtime;
Peter Zijlstra78f2c7d2008-01-25 21:08:27 +01001977 }
1978}
Steven Rostedtcb469842008-01-25 21:08:22 +01001979
Peter Zijlstra8f4d37e2008-01-25 21:08:29 +01001980static void task_tick_rt(struct rq *rq, struct task_struct *p, int queued)
Ingo Molnarbb44e5d2007-07-09 18:51:58 +02001981{
Colin Cross454c7992012-05-16 21:34:23 -07001982 struct sched_rt_entity *rt_se = &p->rt;
1983
Peter Zijlstra67e2be02007-12-20 15:01:17 +01001984 update_curr_rt(rq);
1985
Peter Zijlstra78f2c7d2008-01-25 21:08:27 +01001986 watchdog(rq, p);
1987
Ingo Molnarbb44e5d2007-07-09 18:51:58 +02001988 /*
1989 * RR tasks need a special form of timeslice management.
1990 * FIFO tasks have no timeslices.
1991 */
1992 if (p->policy != SCHED_RR)
1993 return;
1994
Peter Zijlstrafa717062008-01-25 21:08:27 +01001995 if (--p->rt.time_slice)
Ingo Molnarbb44e5d2007-07-09 18:51:58 +02001996 return;
1997
Clark Williamsce0dbbb2013-02-07 09:47:04 -06001998 p->rt.time_slice = sched_rr_timeslice;
Ingo Molnarbb44e5d2007-07-09 18:51:58 +02001999
Dmitry Adamushko98fbc792007-08-24 20:39:10 +02002000 /*
Li Bine9aa39b2013-10-21 20:15:43 +08002001 * Requeue to the end of queue if we (and all of our ancestors) are not
2002 * the only element on the queue
Dmitry Adamushko98fbc792007-08-24 20:39:10 +02002003 */
Colin Cross454c7992012-05-16 21:34:23 -07002004 for_each_sched_rt_entity(rt_se) {
2005 if (rt_se->run_list.prev != rt_se->run_list.next) {
2006 requeue_task_rt(rq, p, 0);
2007 set_tsk_need_resched(p);
2008 return;
2009 }
Dmitry Adamushko98fbc792007-08-24 20:39:10 +02002010 }
Ingo Molnarbb44e5d2007-07-09 18:51:58 +02002011}
2012
Srivatsa Vaddagiri83b699e2007-10-15 17:00:08 +02002013static void set_curr_task_rt(struct rq *rq)
2014{
2015 struct task_struct *p = rq->curr;
2016
Frederic Weisbecker78becc22013-04-12 01:51:02 +02002017 p->se.exec_start = rq_clock_task(rq);
Gregory Haskins917b6272008-12-29 09:39:53 -05002018
2019 /* The running task is never eligible for pushing */
2020 dequeue_pushable_task(rq, p);
Srivatsa Vaddagiri83b699e2007-10-15 17:00:08 +02002021}
2022
H Hartley Sweeten6d686f42010-01-13 20:21:52 -07002023static unsigned int get_rr_interval_rt(struct rq *rq, struct task_struct *task)
Peter Williams0d721ce2009-09-21 01:31:53 +00002024{
2025 /*
2026 * Time slice is 0 for SCHED_FIFO tasks
2027 */
2028 if (task->policy == SCHED_RR)
Clark Williamsce0dbbb2013-02-07 09:47:04 -06002029 return sched_rr_timeslice;
Peter Williams0d721ce2009-09-21 01:31:53 +00002030 else
2031 return 0;
2032}
2033
Peter Zijlstra029632f2011-10-25 10:00:11 +02002034const struct sched_class rt_sched_class = {
Ingo Molnar5522d5d2007-10-15 17:00:12 +02002035 .next = &fair_sched_class,
Ingo Molnarbb44e5d2007-07-09 18:51:58 +02002036 .enqueue_task = enqueue_task_rt,
2037 .dequeue_task = dequeue_task_rt,
2038 .yield_task = yield_task_rt,
2039
2040 .check_preempt_curr = check_preempt_curr_rt,
2041
2042 .pick_next_task = pick_next_task_rt,
2043 .put_prev_task = put_prev_task_rt,
2044
Peter Williams681f3e62007-10-24 18:23:51 +02002045#ifdef CONFIG_SMP
Li Zefan4ce72a22008-10-22 15:25:26 +08002046 .select_task_rq = select_task_rq_rt,
2047
Gregory Haskins73fe6aa2008-01-25 21:08:07 +01002048 .set_cpus_allowed = set_cpus_allowed_rt,
Gregory Haskins1f11eb62008-06-04 15:04:05 -04002049 .rq_online = rq_online_rt,
2050 .rq_offline = rq_offline_rt,
Steven Rostedt9a897c52008-01-25 21:08:22 +01002051 .post_schedule = post_schedule_rt,
Peter Zijlstraefbbd052009-12-16 18:04:40 +01002052 .task_woken = task_woken_rt,
Steven Rostedtcb469842008-01-25 21:08:22 +01002053 .switched_from = switched_from_rt,
Peter Williams681f3e62007-10-24 18:23:51 +02002054#endif
Ingo Molnarbb44e5d2007-07-09 18:51:58 +02002055
Srivatsa Vaddagiri83b699e2007-10-15 17:00:08 +02002056 .set_curr_task = set_curr_task_rt,
Ingo Molnarbb44e5d2007-07-09 18:51:58 +02002057 .task_tick = task_tick_rt,
Steven Rostedtcb469842008-01-25 21:08:22 +01002058
Peter Williams0d721ce2009-09-21 01:31:53 +00002059 .get_rr_interval = get_rr_interval_rt,
2060
Steven Rostedtcb469842008-01-25 21:08:22 +01002061 .prio_changed = prio_changed_rt,
2062 .switched_to = switched_to_rt,
Ingo Molnarbb44e5d2007-07-09 18:51:58 +02002063};
Peter Zijlstraada18de2008-06-19 14:22:24 +02002064
2065#ifdef CONFIG_SCHED_DEBUG
2066extern void print_rt_rq(struct seq_file *m, int cpu, struct rt_rq *rt_rq);
2067
Peter Zijlstra029632f2011-10-25 10:00:11 +02002068void print_rt_stats(struct seq_file *m, int cpu)
Peter Zijlstraada18de2008-06-19 14:22:24 +02002069{
Cheng Xuec514c42011-05-14 14:20:02 +08002070 rt_rq_iter_t iter;
Peter Zijlstraada18de2008-06-19 14:22:24 +02002071 struct rt_rq *rt_rq;
2072
2073 rcu_read_lock();
Cheng Xuec514c42011-05-14 14:20:02 +08002074 for_each_rt_rq(rt_rq, iter, cpu_rq(cpu))
Peter Zijlstraada18de2008-06-19 14:22:24 +02002075 print_rt_rq(m, cpu, rt_rq);
2076 rcu_read_unlock();
2077}
Dhaval Giani55e12e52008-06-24 23:39:43 +05302078#endif /* CONFIG_SCHED_DEBUG */