~ [ source navigation ] ~ [ diff markup ] ~ [ identifier search ] ~

TOMOYO Linux Cross Reference
Linux/kernel/sched/sched.h

Version: ~ [ linux-4.19-rc7 ] ~ [ linux-4.18.12 ] ~ [ linux-4.17.19 ] ~ [ linux-4.16.18 ] ~ [ linux-4.15.18 ] ~ [ linux-4.14.74 ] ~ [ linux-4.13.16 ] ~ [ linux-4.12.14 ] ~ [ linux-4.11.12 ] ~ [ linux-4.10.17 ] ~ [ linux-4.9.131 ] ~ [ linux-4.8.17 ] ~ [ linux-4.7.10 ] ~ [ linux-4.6.7 ] ~ [ linux-4.5.7 ] ~ [ linux-4.4.159 ] ~ [ linux-4.3.6 ] ~ [ linux-4.2.8 ] ~ [ linux-4.1.52 ] ~ [ linux-4.0.9 ] ~ [ linux-3.19.8 ] ~ [ linux-3.18.123 ] ~ [ linux-3.17.8 ] ~ [ linux-3.16.59 ] ~ [ linux-3.15.10 ] ~ [ linux-3.14.79 ] ~ [ linux-3.13.11 ] ~ [ linux-3.12.74 ] ~ [ linux-3.11.10 ] ~ [ linux-3.10.108 ] ~ [ linux-3.9.11 ] ~ [ linux-3.8.13 ] ~ [ linux-3.7.10 ] ~ [ linux-3.6.11 ] ~ [ linux-3.5.7 ] ~ [ linux-3.4.113 ] ~ [ linux-3.3.8 ] ~ [ linux-3.2.102 ] ~ [ linux-3.1.10 ] ~ [ linux-3.0.101 ] ~ [ linux-2.6.39.4 ] ~ [ linux-2.6.38.8 ] ~ [ linux-2.6.37.6 ] ~ [ linux-2.6.36.4 ] ~ [ linux-2.6.35.14 ] ~ [ linux-2.6.34.15 ] ~ [ linux-2.6.33.20 ] ~ [ linux-2.6.32.71 ] ~ [ linux-2.6.31.14 ] ~ [ linux-2.6.30.10 ] ~ [ linux-2.6.29.6 ] ~ [ linux-2.6.28.10 ] ~ [ linux-2.6.27.62 ] ~ [ linux-2.6.0 ] ~ [ linux-2.4.37.11 ] ~ [ unix-v6-master ] ~ [ ccs-tools-1.8.5 ] ~ [ policy-sample ] ~
Architecture: ~ [ i386 ] ~ [ alpha ] ~ [ m68k ] ~ [ mips ] ~ [ ppc ] ~ [ sparc ] ~ [ sparc64 ] ~

  1 /* SPDX-License-Identifier: GPL-2.0 */
  2 /*
  3  * Scheduler internal types and methods:
  4  */
  5 #include <linux/sched.h>
  6 
  7 #include <linux/sched/autogroup.h>
  8 #include <linux/sched/clock.h>
  9 #include <linux/sched/coredump.h>
 10 #include <linux/sched/cpufreq.h>
 11 #include <linux/sched/cputime.h>
 12 #include <linux/sched/deadline.h>
 13 #include <linux/sched/debug.h>
 14 #include <linux/sched/hotplug.h>
 15 #include <linux/sched/idle.h>
 16 #include <linux/sched/init.h>
 17 #include <linux/sched/isolation.h>
 18 #include <linux/sched/jobctl.h>
 19 #include <linux/sched/loadavg.h>
 20 #include <linux/sched/mm.h>
 21 #include <linux/sched/nohz.h>
 22 #include <linux/sched/numa_balancing.h>
 23 #include <linux/sched/prio.h>
 24 #include <linux/sched/rt.h>
 25 #include <linux/sched/signal.h>
 26 #include <linux/sched/stat.h>
 27 #include <linux/sched/sysctl.h>
 28 #include <linux/sched/task.h>
 29 #include <linux/sched/task_stack.h>
 30 #include <linux/sched/topology.h>
 31 #include <linux/sched/user.h>
 32 #include <linux/sched/wake_q.h>
 33 #include <linux/sched/xacct.h>
 34 
 35 #include <uapi/linux/sched/types.h>
 36 
 37 #include <linux/binfmts.h>
 38 #include <linux/blkdev.h>
 39 #include <linux/compat.h>
 40 #include <linux/context_tracking.h>
 41 #include <linux/cpufreq.h>
 42 #include <linux/cpuidle.h>
 43 #include <linux/cpuset.h>
 44 #include <linux/ctype.h>
 45 #include <linux/debugfs.h>
 46 #include <linux/delayacct.h>
 47 #include <linux/init_task.h>
 48 #include <linux/kprobes.h>
 49 #include <linux/kthread.h>
 50 #include <linux/membarrier.h>
 51 #include <linux/migrate.h>
 52 #include <linux/mmu_context.h>
 53 #include <linux/nmi.h>
 54 #include <linux/proc_fs.h>
 55 #include <linux/prefetch.h>
 56 #include <linux/profile.h>
 57 #include <linux/rcupdate_wait.h>
 58 #include <linux/security.h>
 59 #include <linux/stackprotector.h>
 60 #include <linux/stop_machine.h>
 61 #include <linux/suspend.h>
 62 #include <linux/swait.h>
 63 #include <linux/syscalls.h>
 64 #include <linux/task_work.h>
 65 #include <linux/tsacct_kern.h>
 66 
 67 #include <asm/tlb.h>
 68 
 69 #ifdef CONFIG_PARAVIRT
 70 # include <asm/paravirt.h>
 71 #endif
 72 
 73 #include "cpupri.h"
 74 #include "cpudeadline.h"
 75 
 76 #ifdef CONFIG_SCHED_DEBUG
 77 # define SCHED_WARN_ON(x)       WARN_ONCE(x, #x)
 78 #else
 79 # define SCHED_WARN_ON(x)       ({ (void)(x), 0; })
 80 #endif
 81 
 82 struct rq;
 83 struct cpuidle_state;
 84 
 85 /* task_struct::on_rq states: */
 86 #define TASK_ON_RQ_QUEUED       1
 87 #define TASK_ON_RQ_MIGRATING    2
 88 
 89 extern __read_mostly int scheduler_running;
 90 
 91 extern unsigned long calc_load_update;
 92 extern atomic_long_t calc_load_tasks;
 93 
 94 extern void calc_global_load_tick(struct rq *this_rq);
 95 extern long calc_load_fold_active(struct rq *this_rq, long adjust);
 96 
 97 #ifdef CONFIG_SMP
 98 extern void cpu_load_update_active(struct rq *this_rq);
 99 #else
100 static inline void cpu_load_update_active(struct rq *this_rq) { }
101 #endif
102 
103 /*
104  * Helpers for converting nanosecond timing to jiffy resolution
105  */
106 #define NS_TO_JIFFIES(TIME)     ((unsigned long)(TIME) / (NSEC_PER_SEC / HZ))
107 
108 /*
109  * Increase resolution of nice-level calculations for 64-bit architectures.
110  * The extra resolution improves shares distribution and load balancing of
111  * low-weight task groups (eg. nice +19 on an autogroup), deeper taskgroup
112  * hierarchies, especially on larger systems. This is not a user-visible change
113  * and does not change the user-interface for setting shares/weights.
114  *
115  * We increase resolution only if we have enough bits to allow this increased
116  * resolution (i.e. 64-bit). The costs for increasing resolution when 32-bit
117  * are pretty high and the returns do not justify the increased costs.
118  *
119  * Really only required when CONFIG_FAIR_GROUP_SCHED=y is also set, but to
120  * increase coverage and consistency always enable it on 64-bit platforms.
121  */
122 #ifdef CONFIG_64BIT
123 # define NICE_0_LOAD_SHIFT      (SCHED_FIXEDPOINT_SHIFT + SCHED_FIXEDPOINT_SHIFT)
124 # define scale_load(w)          ((w) << SCHED_FIXEDPOINT_SHIFT)
125 # define scale_load_down(w)     ((w) >> SCHED_FIXEDPOINT_SHIFT)
126 #else
127 # define NICE_0_LOAD_SHIFT      (SCHED_FIXEDPOINT_SHIFT)
128 # define scale_load(w)          (w)
129 # define scale_load_down(w)     (w)
130 #endif
131 
132 /*
133  * Task weight (visible to users) and its load (invisible to users) have
134  * independent resolution, but they should be well calibrated. We use
135  * scale_load() and scale_load_down(w) to convert between them. The
136  * following must be true:
137  *
138  *  scale_load(sched_prio_to_weight[USER_PRIO(NICE_TO_PRIO(0))]) == NICE_0_LOAD
139  *
140  */
141 #define NICE_0_LOAD             (1L << NICE_0_LOAD_SHIFT)
142 
143 /*
144  * Single value that decides SCHED_DEADLINE internal math precision.
145  * 10 -> just above 1us
146  * 9  -> just above 0.5us
147  */
148 #define DL_SCALE                10
149 
150 /*
151  * Single value that denotes runtime == period, ie unlimited time.
152  */
153 #define RUNTIME_INF             ((u64)~0ULL)
154 
155 static inline int idle_policy(int policy)
156 {
157         return policy == SCHED_IDLE;
158 }
159 static inline int fair_policy(int policy)
160 {
161         return policy == SCHED_NORMAL || policy == SCHED_BATCH;
162 }
163 
164 static inline int rt_policy(int policy)
165 {
166         return policy == SCHED_FIFO || policy == SCHED_RR;
167 }
168 
169 static inline int dl_policy(int policy)
170 {
171         return policy == SCHED_DEADLINE;
172 }
173 static inline bool valid_policy(int policy)
174 {
175         return idle_policy(policy) || fair_policy(policy) ||
176                 rt_policy(policy) || dl_policy(policy);
177 }
178 
179 static inline int task_has_rt_policy(struct task_struct *p)
180 {
181         return rt_policy(p->policy);
182 }
183 
184 static inline int task_has_dl_policy(struct task_struct *p)
185 {
186         return dl_policy(p->policy);
187 }
188 
189 #define cap_scale(v, s) ((v)*(s) >> SCHED_CAPACITY_SHIFT)
190 
191 /*
192  * !! For sched_setattr_nocheck() (kernel) only !!
193  *
194  * This is actually gross. :(
195  *
196  * It is used to make schedutil kworker(s) higher priority than SCHED_DEADLINE
197  * tasks, but still be able to sleep. We need this on platforms that cannot
198  * atomically change clock frequency. Remove once fast switching will be
199  * available on such platforms.
200  *
201  * SUGOV stands for SchedUtil GOVernor.
202  */
203 #define SCHED_FLAG_SUGOV        0x10000000
204 
205 static inline bool dl_entity_is_special(struct sched_dl_entity *dl_se)
206 {
207 #ifdef CONFIG_CPU_FREQ_GOV_SCHEDUTIL
208         return unlikely(dl_se->flags & SCHED_FLAG_SUGOV);
209 #else
210         return false;
211 #endif
212 }
213 
214 /*
215  * Tells if entity @a should preempt entity @b.
216  */
217 static inline bool
218 dl_entity_preempt(struct sched_dl_entity *a, struct sched_dl_entity *b)
219 {
220         return dl_entity_is_special(a) ||
221                dl_time_before(a->deadline, b->deadline);
222 }
223 
224 /*
225  * This is the priority-queue data structure of the RT scheduling class:
226  */
227 struct rt_prio_array {
228         DECLARE_BITMAP(bitmap, MAX_RT_PRIO+1); /* include 1 bit for delimiter */
229         struct list_head queue[MAX_RT_PRIO];
230 };
231 
232 struct rt_bandwidth {
233         /* nests inside the rq lock: */
234         raw_spinlock_t          rt_runtime_lock;
235         ktime_t                 rt_period;
236         u64                     rt_runtime;
237         struct hrtimer          rt_period_timer;
238         unsigned int            rt_period_active;
239 };
240 
241 void __dl_clear_params(struct task_struct *p);
242 
243 /*
244  * To keep the bandwidth of -deadline tasks and groups under control
245  * we need some place where:
246  *  - store the maximum -deadline bandwidth of the system (the group);
247  *  - cache the fraction of that bandwidth that is currently allocated.
248  *
249  * This is all done in the data structure below. It is similar to the
250  * one used for RT-throttling (rt_bandwidth), with the main difference
251  * that, since here we are only interested in admission control, we
252  * do not decrease any runtime while the group "executes", neither we
253  * need a timer to replenish it.
254  *
255  * With respect to SMP, the bandwidth is given on a per-CPU basis,
256  * meaning that:
257  *  - dl_bw (< 100%) is the bandwidth of the system (group) on each CPU;
258  *  - dl_total_bw array contains, in the i-eth element, the currently
259  *    allocated bandwidth on the i-eth CPU.
260  * Moreover, groups consume bandwidth on each CPU, while tasks only
261  * consume bandwidth on the CPU they're running on.
262  * Finally, dl_total_bw_cpu is used to cache the index of dl_total_bw
263  * that will be shown the next time the proc or cgroup controls will
264  * be red. It on its turn can be changed by writing on its own
265  * control.
266  */
267 struct dl_bandwidth {
268         raw_spinlock_t          dl_runtime_lock;
269         u64                     dl_runtime;
270         u64                     dl_period;
271 };
272 
273 static inline int dl_bandwidth_enabled(void)
274 {
275         return sysctl_sched_rt_runtime >= 0;
276 }
277 
278 struct dl_bw {
279         raw_spinlock_t          lock;
280         u64                     bw;
281         u64                     total_bw;
282 };
283 
284 static inline void __dl_update(struct dl_bw *dl_b, s64 bw);
285 
286 static inline
287 void __dl_sub(struct dl_bw *dl_b, u64 tsk_bw, int cpus)
288 {
289         dl_b->total_bw -= tsk_bw;
290         __dl_update(dl_b, (s32)tsk_bw / cpus);
291 }
292 
293 static inline
294 void __dl_add(struct dl_bw *dl_b, u64 tsk_bw, int cpus)
295 {
296         dl_b->total_bw += tsk_bw;
297         __dl_update(dl_b, -((s32)tsk_bw / cpus));
298 }
299 
300 static inline
301 bool __dl_overflow(struct dl_bw *dl_b, int cpus, u64 old_bw, u64 new_bw)
302 {
303         return dl_b->bw != -1 &&
304                dl_b->bw * cpus < dl_b->total_bw - old_bw + new_bw;
305 }
306 
307 extern void dl_change_utilization(struct task_struct *p, u64 new_bw);
308 extern void init_dl_bw(struct dl_bw *dl_b);
309 extern int  sched_dl_global_validate(void);
310 extern void sched_dl_do_global(void);
311 extern int  sched_dl_overflow(struct task_struct *p, int policy, const struct sched_attr *attr);
312 extern void __setparam_dl(struct task_struct *p, const struct sched_attr *attr);
313 extern void __getparam_dl(struct task_struct *p, struct sched_attr *attr);
314 extern bool __checkparam_dl(const struct sched_attr *attr);
315 extern bool dl_param_changed(struct task_struct *p, const struct sched_attr *attr);
316 extern int  dl_task_can_attach(struct task_struct *p, const struct cpumask *cs_cpus_allowed);
317 extern int  dl_cpuset_cpumask_can_shrink(const struct cpumask *cur, const struct cpumask *trial);
318 extern bool dl_cpu_busy(unsigned int cpu);
319 
320 #ifdef CONFIG_CGROUP_SCHED
321 
322 #include <linux/cgroup.h>
323 
324 struct cfs_rq;
325 struct rt_rq;
326 
327 extern struct list_head task_groups;
328 
329 struct cfs_bandwidth {
330 #ifdef CONFIG_CFS_BANDWIDTH
331         raw_spinlock_t          lock;
332         ktime_t                 period;
333         u64                     quota;
334         u64                     runtime;
335         s64                     hierarchical_quota;
336         u64                     runtime_expires;
337         int                     expires_seq;
338 
339         short                   idle;
340         short                   period_active;
341         struct hrtimer          period_timer;
342         struct hrtimer          slack_timer;
343         struct list_head        throttled_cfs_rq;
344 
345         /* Statistics: */
346         int                     nr_periods;
347         int                     nr_throttled;
348         u64                     throttled_time;
349 #endif
350 };
351 
352 /* Task group related information */
353 struct task_group {
354         struct cgroup_subsys_state css;
355 
356 #ifdef CONFIG_FAIR_GROUP_SCHED
357         /* schedulable entities of this group on each CPU */
358         struct sched_entity     **se;
359         /* runqueue "owned" by this group on each CPU */
360         struct cfs_rq           **cfs_rq;
361         unsigned long           shares;
362 
363 #ifdef  CONFIG_SMP
364         /*
365          * load_avg can be heavily contended at clock tick time, so put
366          * it in its own cacheline separated from the fields above which
367          * will also be accessed at each tick.
368          */
369         atomic_long_t           load_avg ____cacheline_aligned;
370 #endif
371 #endif
372 
373 #ifdef CONFIG_RT_GROUP_SCHED
374         struct sched_rt_entity  **rt_se;
375         struct rt_rq            **rt_rq;
376 
377         struct rt_bandwidth     rt_bandwidth;
378 #endif
379 
380         struct rcu_head         rcu;
381         struct list_head        list;
382 
383         struct task_group       *parent;
384         struct list_head        siblings;
385         struct list_head        children;
386 
387 #ifdef CONFIG_SCHED_AUTOGROUP
388         struct autogroup        *autogroup;
389 #endif
390 
391         struct cfs_bandwidth    cfs_bandwidth;
392 };
393 
394 #ifdef CONFIG_FAIR_GROUP_SCHED
395 #define ROOT_TASK_GROUP_LOAD    NICE_0_LOAD
396 
397 /*
398  * A weight of 0 or 1 can cause arithmetics problems.
399  * A weight of a cfs_rq is the sum of weights of which entities
400  * are queued on this cfs_rq, so a weight of a entity should not be
401  * too large, so as the shares value of a task group.
402  * (The default weight is 1024 - so there's no practical
403  *  limitation from this.)
404  */
405 #define MIN_SHARES              (1UL <<  1)
406 #define MAX_SHARES              (1UL << 18)
407 #endif
408 
409 typedef int (*tg_visitor)(struct task_group *, void *);
410 
411 extern int walk_tg_tree_from(struct task_group *from,
412                              tg_visitor down, tg_visitor up, void *data);
413 
414 /*
415  * Iterate the full tree, calling @down when first entering a node and @up when
416  * leaving it for the final time.
417  *
418  * Caller must hold rcu_lock or sufficient equivalent.
419  */
420 static inline int walk_tg_tree(tg_visitor down, tg_visitor up, void *data)
421 {
422         return walk_tg_tree_from(&root_task_group, down, up, data);
423 }
424 
425 extern int tg_nop(struct task_group *tg, void *data);
426 
427 extern void free_fair_sched_group(struct task_group *tg);
428 extern int alloc_fair_sched_group(struct task_group *tg, struct task_group *parent);
429 extern void online_fair_sched_group(struct task_group *tg);
430 extern void unregister_fair_sched_group(struct task_group *tg);
431 extern void init_tg_cfs_entry(struct task_group *tg, struct cfs_rq *cfs_rq,
432                         struct sched_entity *se, int cpu,
433                         struct sched_entity *parent);
434 extern void init_cfs_bandwidth(struct cfs_bandwidth *cfs_b);
435 
436 extern void __refill_cfs_bandwidth_runtime(struct cfs_bandwidth *cfs_b);
437 extern void start_cfs_bandwidth(struct cfs_bandwidth *cfs_b);
438 extern void unthrottle_cfs_rq(struct cfs_rq *cfs_rq);
439 
440 extern void free_rt_sched_group(struct task_group *tg);
441 extern int alloc_rt_sched_group(struct task_group *tg, struct task_group *parent);
442 extern void init_tg_rt_entry(struct task_group *tg, struct rt_rq *rt_rq,
443                 struct sched_rt_entity *rt_se, int cpu,
444                 struct sched_rt_entity *parent);
445 extern int sched_group_set_rt_runtime(struct task_group *tg, long rt_runtime_us);
446 extern int sched_group_set_rt_period(struct task_group *tg, u64 rt_period_us);
447 extern long sched_group_rt_runtime(struct task_group *tg);
448 extern long sched_group_rt_period(struct task_group *tg);
449 extern int sched_rt_can_attach(struct task_group *tg, struct task_struct *tsk);
450 
451 extern struct task_group *sched_create_group(struct task_group *parent);
452 extern void sched_online_group(struct task_group *tg,
453                                struct task_group *parent);
454 extern void sched_destroy_group(struct task_group *tg);
455 extern void sched_offline_group(struct task_group *tg);
456 
457 extern void sched_move_task(struct task_struct *tsk);
458 
459 #ifdef CONFIG_FAIR_GROUP_SCHED
460 extern int sched_group_set_shares(struct task_group *tg, unsigned long shares);
461 
462 #ifdef CONFIG_SMP
463 extern void set_task_rq_fair(struct sched_entity *se,
464                              struct cfs_rq *prev, struct cfs_rq *next);
465 #else /* !CONFIG_SMP */
466 static inline void set_task_rq_fair(struct sched_entity *se,
467                              struct cfs_rq *prev, struct cfs_rq *next) { }
468 #endif /* CONFIG_SMP */
469 #endif /* CONFIG_FAIR_GROUP_SCHED */
470 
471 #else /* CONFIG_CGROUP_SCHED */
472 
473 struct cfs_bandwidth { };
474 
475 #endif  /* CONFIG_CGROUP_SCHED */
476 
477 /* CFS-related fields in a runqueue */
478 struct cfs_rq {
479         struct load_weight      load;
480         unsigned long           runnable_weight;
481         unsigned int            nr_running;
482         unsigned int            h_nr_running;
483 
484         u64                     exec_clock;
485         u64                     min_vruntime;
486 #ifndef CONFIG_64BIT
487         u64                     min_vruntime_copy;
488 #endif
489 
490         struct rb_root_cached   tasks_timeline;
491 
492         /*
493          * 'curr' points to currently running entity on this cfs_rq.
494          * It is set to NULL otherwise (i.e when none are currently running).
495          */
496         struct sched_entity     *curr;
497         struct sched_entity     *next;
498         struct sched_entity     *last;
499         struct sched_entity     *skip;
500 
501 #ifdef  CONFIG_SCHED_DEBUG
502         unsigned int            nr_spread_over;
503 #endif
504 
505 #ifdef CONFIG_SMP
506         /*
507          * CFS load tracking
508          */
509         struct sched_avg        avg;
510 #ifndef CONFIG_64BIT
511         u64                     load_last_update_time_copy;
512 #endif
513         struct {
514                 raw_spinlock_t  lock ____cacheline_aligned;
515                 int             nr;
516                 unsigned long   load_avg;
517                 unsigned long   util_avg;
518                 unsigned long   runnable_sum;
519         } removed;
520 
521 #ifdef CONFIG_FAIR_GROUP_SCHED
522         unsigned long           tg_load_avg_contrib;
523         long                    propagate;
524         long                    prop_runnable_sum;
525 
526         /*
527          *   h_load = weight * f(tg)
528          *
529          * Where f(tg) is the recursive weight fraction assigned to
530          * this group.
531          */
532         unsigned long           h_load;
533         u64                     last_h_load_update;
534         struct sched_entity     *h_load_next;
535 #endif /* CONFIG_FAIR_GROUP_SCHED */
536 #endif /* CONFIG_SMP */
537 
538 #ifdef CONFIG_FAIR_GROUP_SCHED
539         struct rq               *rq;    /* CPU runqueue to which this cfs_rq is attached */
540 
541         /*
542          * leaf cfs_rqs are those that hold tasks (lowest schedulable entity in
543          * a hierarchy). Non-leaf lrqs hold other higher schedulable entities
544          * (like users, containers etc.)
545          *
546          * leaf_cfs_rq_list ties together list of leaf cfs_rq's in a CPU.
547          * This list is used during load balance.
548          */
549         int                     on_list;
550         struct list_head        leaf_cfs_rq_list;
551         struct task_group       *tg;    /* group that "owns" this runqueue */
552 
553 #ifdef CONFIG_CFS_BANDWIDTH
554         int                     runtime_enabled;
555         int                     expires_seq;
556         u64                     runtime_expires;
557         s64                     runtime_remaining;
558 
559         u64                     throttled_clock;
560         u64                     throttled_clock_task;
561         u64                     throttled_clock_task_time;
562         int                     throttled;
563         int                     throttle_count;
564         struct list_head        throttled_list;
565 #endif /* CONFIG_CFS_BANDWIDTH */
566 #endif /* CONFIG_FAIR_GROUP_SCHED */
567 };
568 
569 static inline int rt_bandwidth_enabled(void)
570 {
571         return sysctl_sched_rt_runtime >= 0;
572 }
573 
574 /* RT IPI pull logic requires IRQ_WORK */
575 #if defined(CONFIG_IRQ_WORK) && defined(CONFIG_SMP)
576 # define HAVE_RT_PUSH_IPI
577 #endif
578 
579 /* Real-Time classes' related field in a runqueue: */
580 struct rt_rq {
581         struct rt_prio_array    active;
582         unsigned int            rt_nr_running;
583         unsigned int            rr_nr_running;
584 #if defined CONFIG_SMP || defined CONFIG_RT_GROUP_SCHED
585         struct {
586                 int             curr; /* highest queued rt task prio */
587 #ifdef CONFIG_SMP
588                 int             next; /* next highest */
589 #endif
590         } highest_prio;
591 #endif
592 #ifdef CONFIG_SMP
593         unsigned long           rt_nr_migratory;
594         unsigned long           rt_nr_total;
595         int                     overloaded;
596         struct plist_head       pushable_tasks;
597 
598 #endif /* CONFIG_SMP */
599         int                     rt_queued;
600 
601         int                     rt_throttled;
602         u64                     rt_time;
603         u64                     rt_runtime;
604         /* Nests inside the rq lock: */
605         raw_spinlock_t          rt_runtime_lock;
606 
607 #ifdef CONFIG_RT_GROUP_SCHED
608         unsigned long           rt_nr_boosted;
609 
610         struct rq               *rq;
611         struct task_group       *tg;
612 #endif
613 };
614 
615 static inline bool rt_rq_is_runnable(struct rt_rq *rt_rq)
616 {
617         return rt_rq->rt_queued && rt_rq->rt_nr_running;
618 }
619 
620 /* Deadline class' related fields in a runqueue */
621 struct dl_rq {
622         /* runqueue is an rbtree, ordered by deadline */
623         struct rb_root_cached   root;
624 
625         unsigned long           dl_nr_running;
626 
627 #ifdef CONFIG_SMP
628         /*
629          * Deadline values of the currently executing and the
630          * earliest ready task on this rq. Caching these facilitates
631          * the decision wether or not a ready but not running task
632          * should migrate somewhere else.
633          */
634         struct {
635                 u64             curr;
636                 u64             next;
637         } earliest_dl;
638 
639         unsigned long           dl_nr_migratory;
640         int                     overloaded;
641 
642         /*
643          * Tasks on this rq that can be pushed away. They are kept in
644          * an rb-tree, ordered by tasks' deadlines, with caching
645          * of the leftmost (earliest deadline) element.
646          */
647         struct rb_root_cached   pushable_dl_tasks_root;
648 #else
649         struct dl_bw            dl_bw;
650 #endif
651         /*
652          * "Active utilization" for this runqueue: increased when a
653          * task wakes up (becomes TASK_RUNNING) and decreased when a
654          * task blocks
655          */
656         u64                     running_bw;
657 
658         /*
659          * Utilization of the tasks "assigned" to this runqueue (including
660          * the tasks that are in runqueue and the tasks that executed on this
661          * CPU and blocked). Increased when a task moves to this runqueue, and
662          * decreased when the task moves away (migrates, changes scheduling
663          * policy, or terminates).
664          * This is needed to compute the "inactive utilization" for the
665          * runqueue (inactive utilization = this_bw - running_bw).
666          */
667         u64                     this_bw;
668         u64                     extra_bw;
669 
670         /*
671          * Inverse of the fraction of CPU utilization that can be reclaimed
672          * by the GRUB algorithm.
673          */
674         u64                     bw_ratio;
675 };
676 
677 #ifdef CONFIG_FAIR_GROUP_SCHED
678 /* An entity is a task if it doesn't "own" a runqueue */
679 #define entity_is_task(se)      (!se->my_q)
680 #else
681 #define entity_is_task(se)      1
682 #endif
683 
684 #ifdef CONFIG_SMP
685 /*
686  * XXX we want to get rid of these helpers and use the full load resolution.
687  */
688 static inline long se_weight(struct sched_entity *se)
689 {
690         return scale_load_down(se->load.weight);
691 }
692 
693 static inline long se_runnable(struct sched_entity *se)
694 {
695         return scale_load_down(se->runnable_weight);
696 }
697 
698 static inline bool sched_asym_prefer(int a, int b)
699 {
700         return arch_asym_cpu_priority(a) > arch_asym_cpu_priority(b);
701 }
702 
703 /*
704  * We add the notion of a root-domain which will be used to define per-domain
705  * variables. Each exclusive cpuset essentially defines an island domain by
706  * fully partitioning the member CPUs from any other cpuset. Whenever a new
707  * exclusive cpuset is created, we also create and attach a new root-domain
708  * object.
709  *
710  */
711 struct root_domain {
712         atomic_t                refcount;
713         atomic_t                rto_count;
714         struct rcu_head         rcu;
715         cpumask_var_t           span;
716         cpumask_var_t           online;
717 
718         /* Indicate more than one runnable task for any CPU */
719         bool                    overload;
720 
721         /*
722          * The bit corresponding to a CPU gets set here if such CPU has more
723          * than one runnable -deadline task (as it is below for RT tasks).
724          */
725         cpumask_var_t           dlo_mask;
726         atomic_t                dlo_count;
727         struct dl_bw            dl_bw;
728         struct cpudl            cpudl;
729 
730 #ifdef HAVE_RT_PUSH_IPI
731         /*
732          * For IPI pull requests, loop across the rto_mask.
733          */
734         struct irq_work         rto_push_work;
735         raw_spinlock_t          rto_lock;
736         /* These are only updated and read within rto_lock */
737         int                     rto_loop;
738         int                     rto_cpu;
739         /* These atomics are updated outside of a lock */
740         atomic_t                rto_loop_next;
741         atomic_t                rto_loop_start;
742 #endif
743         /*
744          * The "RT overload" flag: it gets set if a CPU has more than
745          * one runnable RT task.
746          */
747         cpumask_var_t           rto_mask;
748         struct cpupri           cpupri;
749 
750         unsigned long           max_cpu_capacity;
751 };
752 
753 extern struct root_domain def_root_domain;
754 extern struct mutex sched_domains_mutex;
755 
756 extern void init_defrootdomain(void);
757 extern int sched_init_domains(const struct cpumask *cpu_map);
758 extern void rq_attach_root(struct rq *rq, struct root_domain *rd);
759 extern void sched_get_rd(struct root_domain *rd);
760 extern void sched_put_rd(struct root_domain *rd);
761 
762 #ifdef HAVE_RT_PUSH_IPI
763 extern void rto_push_irq_work_func(struct irq_work *work);
764 #endif
765 #endif /* CONFIG_SMP */
766 
767 /*
768  * This is the main, per-CPU runqueue data structure.
769  *
770  * Locking rule: those places that want to lock multiple runqueues
771  * (such as the load balancing or the thread migration code), lock
772  * acquire operations must be ordered by ascending &runqueue.
773  */
774 struct rq {
775         /* runqueue lock: */
776         raw_spinlock_t          lock;
777 
778         /*
779          * nr_running and cpu_load should be in the same cacheline because
780          * remote CPUs use both these fields when doing load calculation.
781          */
782         unsigned int            nr_running;
783 #ifdef CONFIG_NUMA_BALANCING
784         unsigned int            nr_numa_running;
785         unsigned int            nr_preferred_running;
786         unsigned int            numa_migrate_on;
787 #endif
788         #define CPU_LOAD_IDX_MAX 5
789         unsigned long           cpu_load[CPU_LOAD_IDX_MAX];
790 #ifdef CONFIG_NO_HZ_COMMON
791 #ifdef CONFIG_SMP
792         unsigned long           last_load_update_tick;
793         unsigned long           last_blocked_load_update_tick;
794         unsigned int            has_blocked_load;
795 #endif /* CONFIG_SMP */
796         unsigned int            nohz_tick_stopped;
797         atomic_t nohz_flags;
798 #endif /* CONFIG_NO_HZ_COMMON */
799 
800         /* capture load from *all* tasks on this CPU: */
801         struct load_weight      load;
802         unsigned long           nr_load_updates;
803         u64                     nr_switches;
804 
805         struct cfs_rq           cfs;
806         struct rt_rq            rt;
807         struct dl_rq            dl;
808 
809 #ifdef CONFIG_FAIR_GROUP_SCHED
810         /* list of leaf cfs_rq on this CPU: */
811         struct list_head        leaf_cfs_rq_list;
812         struct list_head        *tmp_alone_branch;
813 #endif /* CONFIG_FAIR_GROUP_SCHED */
814 
815         /*
816          * This is part of a global counter where only the total sum
817          * over all CPUs matters. A task can increase this counter on
818          * one CPU and if it got migrated afterwards it may decrease
819          * it on another CPU. Always updated under the runqueue lock:
820          */
821         unsigned long           nr_uninterruptible;
822 
823         struct task_struct      *curr;
824         struct task_struct      *idle;
825         struct task_struct      *stop;
826         unsigned long           next_balance;
827         struct mm_struct        *prev_mm;
828 
829         unsigned int            clock_update_flags;
830         u64                     clock;
831         u64                     clock_task;
832 
833         atomic_t                nr_iowait;
834 
835 #ifdef CONFIG_SMP
836         struct root_domain      *rd;
837         struct sched_domain     *sd;
838 
839         unsigned long           cpu_capacity;
840         unsigned long           cpu_capacity_orig;
841 
842         struct callback_head    *balance_callback;
843 
844         unsigned char           idle_balance;
845 
846         /* For active balancing */
847         int                     active_balance;
848         int                     push_cpu;
849         struct cpu_stop_work    active_balance_work;
850 
851         /* CPU of this runqueue: */
852         int                     cpu;
853         int                     online;
854 
855         struct list_head cfs_tasks;
856 
857         struct sched_avg        avg_rt;
858         struct sched_avg        avg_dl;
859 #if defined(CONFIG_IRQ_TIME_ACCOUNTING) || defined(CONFIG_PARAVIRT_TIME_ACCOUNTING)
860 #define HAVE_SCHED_AVG_IRQ
861         struct sched_avg        avg_irq;
862 #endif
863         u64                     idle_stamp;
864         u64                     avg_idle;
865 
866         /* This is used to determine avg_idle's max value */
867         u64                     max_idle_balance_cost;
868 #endif
869 
870 #ifdef CONFIG_IRQ_TIME_ACCOUNTING
871         u64                     prev_irq_time;
872 #endif
873 #ifdef CONFIG_PARAVIRT
874         u64                     prev_steal_time;
875 #endif
876 #ifdef CONFIG_PARAVIRT_TIME_ACCOUNTING
877         u64                     prev_steal_time_rq;
878 #endif
879 
880         /* calc_load related fields */
881         unsigned long           calc_load_update;
882         long                    calc_load_active;
883 
884 #ifdef CONFIG_SCHED_HRTICK
885 #ifdef CONFIG_SMP
886         int                     hrtick_csd_pending;
887         call_single_data_t      hrtick_csd;
888 #endif
889         struct hrtimer          hrtick_timer;
890 #endif
891 
892 #ifdef CONFIG_SCHEDSTATS
893         /* latency stats */
894         struct sched_info       rq_sched_info;
895         unsigned long long      rq_cpu_time;
896         /* could above be rq->cfs_rq.exec_clock + rq->rt_rq.rt_runtime ? */
897 
898         /* sys_sched_yield() stats */
899         unsigned int            yld_count;
900 
901         /* schedule() stats */
902         unsigned int            sched_count;
903         unsigned int            sched_goidle;
904 
905         /* try_to_wake_up() stats */
906         unsigned int            ttwu_count;
907         unsigned int            ttwu_local;
908 #endif
909 
910 #ifdef CONFIG_SMP
911         struct llist_head       wake_list;
912 #endif
913 
914 #ifdef CONFIG_CPU_IDLE
915         /* Must be inspected within a rcu lock section */
916         struct cpuidle_state    *idle_state;
917 #endif
918 };
919 
920 static inline int cpu_of(struct rq *rq)
921 {
922 #ifdef CONFIG_SMP
923         return rq->cpu;
924 #else
925         return 0;
926 #endif
927 }
928 
929 
930 #ifdef CONFIG_SCHED_SMT
931 
932 extern struct static_key_false sched_smt_present;
933 
934 extern void __update_idle_core(struct rq *rq);
935 
936 static inline void update_idle_core(struct rq *rq)
937 {
938         if (static_branch_unlikely(&sched_smt_present))
939                 __update_idle_core(rq);
940 }
941 
942 #else
943 static inline void update_idle_core(struct rq *rq) { }
944 #endif
945 
946 DECLARE_PER_CPU_SHARED_ALIGNED(struct rq, runqueues);
947 
948 #define cpu_rq(cpu)             (&per_cpu(runqueues, (cpu)))
949 #define this_rq()               this_cpu_ptr(&runqueues)
950 #define task_rq(p)              cpu_rq(task_cpu(p))
951 #define cpu_curr(cpu)           (cpu_rq(cpu)->curr)
952 #define raw_rq()                raw_cpu_ptr(&runqueues)
953 
954 static inline u64 __rq_clock_broken(struct rq *rq)
955 {
956         return READ_ONCE(rq->clock);
957 }
958 
959 /*
960  * rq::clock_update_flags bits
961  *
962  * %RQCF_REQ_SKIP - will request skipping of clock update on the next
963  *  call to __schedule(). This is an optimisation to avoid
964  *  neighbouring rq clock updates.
965  *
966  * %RQCF_ACT_SKIP - is set from inside of __schedule() when skipping is
967  *  in effect and calls to update_rq_clock() are being ignored.
968  *
969  * %RQCF_UPDATED - is a debug flag that indicates whether a call has been
970  *  made to update_rq_clock() since the last time rq::lock was pinned.
971  *
972  * If inside of __schedule(), clock_update_flags will have been
973  * shifted left (a left shift is a cheap operation for the fast path
974  * to promote %RQCF_REQ_SKIP to %RQCF_ACT_SKIP), so you must use,
975  *
976  *      if (rq-clock_update_flags >= RQCF_UPDATED)
977  *
978  * to check if %RQCF_UPADTED is set. It'll never be shifted more than
979  * one position though, because the next rq_unpin_lock() will shift it
980  * back.
981  */
982 #define RQCF_REQ_SKIP           0x01
983 #define RQCF_ACT_SKIP           0x02
984 #define RQCF_UPDATED            0x04
985 
986 static inline void assert_clock_updated(struct rq *rq)
987 {
988         /*
989          * The only reason for not seeing a clock update since the
990          * last rq_pin_lock() is if we're currently skipping updates.
991          */
992         SCHED_WARN_ON(rq->clock_update_flags < RQCF_ACT_SKIP);
993 }
994 
995 static inline u64 rq_clock(struct rq *rq)
996 {
997         lockdep_assert_held(&rq->lock);
998         assert_clock_updated(rq);
999 
1000         return rq->clock;
1001 }
1002 
1003 static inline u64 rq_clock_task(struct rq *rq)
1004 {
1005         lockdep_assert_held(&rq->lock);
1006         assert_clock_updated(rq);
1007 
1008         return rq->clock_task;
1009 }
1010 
1011 static inline void rq_clock_skip_update(struct rq *rq)
1012 {
1013         lockdep_assert_held(&rq->lock);
1014         rq->clock_update_flags |= RQCF_REQ_SKIP;
1015 }
1016 
1017 /*
1018  * See rt task throttling, which is the only time a skip
1019  * request is cancelled.
1020  */
1021 static inline void rq_clock_cancel_skipupdate(struct rq *rq)
1022 {
1023         lockdep_assert_held(&rq->lock);
1024         rq->clock_update_flags &= ~RQCF_REQ_SKIP;
1025 }
1026 
1027 struct rq_flags {
1028         unsigned long flags;
1029         struct pin_cookie cookie;
1030 #ifdef CONFIG_SCHED_DEBUG
1031         /*
1032          * A copy of (rq::clock_update_flags & RQCF_UPDATED) for the
1033          * current pin context is stashed here in case it needs to be
1034          * restored in rq_repin_lock().
1035          */
1036         unsigned int clock_update_flags;
1037 #endif
1038 };
1039 
1040 static inline void rq_pin_lock(struct rq *rq, struct rq_flags *rf)
1041 {
1042         rf->cookie = lockdep_pin_lock(&rq->lock);
1043 
1044 #ifdef CONFIG_SCHED_DEBUG
1045         rq->clock_update_flags &= (RQCF_REQ_SKIP|RQCF_ACT_SKIP);
1046         rf->clock_update_flags = 0;
1047 #endif
1048 }
1049 
1050 static inline void rq_unpin_lock(struct rq *rq, struct rq_flags *rf)
1051 {
1052 #ifdef CONFIG_SCHED_DEBUG
1053         if (rq->clock_update_flags > RQCF_ACT_SKIP)
1054                 rf->clock_update_flags = RQCF_UPDATED;
1055 #endif
1056 
1057         lockdep_unpin_lock(&rq->lock, rf->cookie);
1058 }
1059 
1060 static inline void rq_repin_lock(struct rq *rq, struct rq_flags *rf)
1061 {
1062         lockdep_repin_lock(&rq->lock, rf->cookie);
1063 
1064 #ifdef CONFIG_SCHED_DEBUG
1065         /*
1066          * Restore the value we stashed in @rf for this pin context.
1067          */
1068         rq->clock_update_flags |= rf->clock_update_flags;
1069 #endif
1070 }
1071 
1072 #ifdef CONFIG_NUMA
1073 enum numa_topology_type {
1074         NUMA_DIRECT,
1075         NUMA_GLUELESS_MESH,
1076         NUMA_BACKPLANE,
1077 };
1078 extern enum numa_topology_type sched_numa_topology_type;
1079 extern int sched_max_numa_distance;
1080 extern bool find_numa_distance(int distance);
1081 #endif
1082 
1083 #ifdef CONFIG_NUMA
1084 extern void sched_init_numa(void);
1085 extern void sched_domains_numa_masks_set(unsigned int cpu);
1086 extern void sched_domains_numa_masks_clear(unsigned int cpu);
1087 #else
1088 static inline void sched_init_numa(void) { }
1089 static inline void sched_domains_numa_masks_set(unsigned int cpu) { }
1090 static inline void sched_domains_numa_masks_clear(unsigned int cpu) { }
1091 #endif
1092 
1093 #ifdef CONFIG_NUMA_BALANCING
1094 /* The regions in numa_faults array from task_struct */
1095 enum numa_faults_stats {
1096         NUMA_MEM = 0,
1097         NUMA_CPU,
1098         NUMA_MEMBUF,
1099         NUMA_CPUBUF
1100 };
1101 extern void sched_setnuma(struct task_struct *p, int node);
1102 extern int migrate_task_to(struct task_struct *p, int cpu);
1103 extern int migrate_swap(struct task_struct *p, struct task_struct *t,
1104                         int cpu, int scpu);
1105 extern void init_numa_balancing(unsigned long clone_flags, struct task_struct *p);
1106 #else
1107 static inline void
1108 init_numa_balancing(unsigned long clone_flags, struct task_struct *p)
1109 {
1110 }
1111 #endif /* CONFIG_NUMA_BALANCING */
1112 
1113 #ifdef CONFIG_SMP
1114 
1115 static inline void
1116 queue_balance_callback(struct rq *rq,
1117                        struct callback_head *head,
1118                        void (*func)(struct rq *rq))
1119 {
1120         lockdep_assert_held(&rq->lock);
1121 
1122         if (unlikely(head->next))
1123                 return;
1124 
1125         head->func = (void (*)(struct callback_head *))func;
1126         head->next = rq->balance_callback;
1127         rq->balance_callback = head;
1128 }
1129 
1130 extern void sched_ttwu_pending(void);
1131 
1132 #define rcu_dereference_check_sched_domain(p) \
1133         rcu_dereference_check((p), \
1134                               lockdep_is_held(&sched_domains_mutex))
1135 
1136 /*
1137  * The domain tree (rq->sd) is protected by RCU's quiescent state transition.
1138  * See detach_destroy_domains: synchronize_sched for details.
1139  *
1140  * The domain tree of any CPU may only be accessed from within
1141  * preempt-disabled sections.
1142  */
1143 #define for_each_domain(cpu, __sd) \
1144         for (__sd = rcu_dereference_check_sched_domain(cpu_rq(cpu)->sd); \
1145                         __sd; __sd = __sd->parent)
1146 
1147 #define for_each_lower_domain(sd) for (; sd; sd = sd->child)
1148 
1149 /**
1150  * highest_flag_domain - Return highest sched_domain containing flag.
1151  * @cpu:        The CPU whose highest level of sched domain is to
1152  *              be returned.
1153  * @flag:       The flag to check for the highest sched_domain
1154  *              for the given CPU.
1155  *
1156  * Returns the highest sched_domain of a CPU which contains the given flag.
1157  */
1158 static inline struct sched_domain *highest_flag_domain(int cpu, int flag)
1159 {
1160         struct sched_domain *sd, *hsd = NULL;
1161 
1162         for_each_domain(cpu, sd) {
1163                 if (!(sd->flags & flag))
1164                         break;
1165                 hsd = sd;
1166         }
1167 
1168         return hsd;
1169 }
1170 
1171 static inline struct sched_domain *lowest_flag_domain(int cpu, int flag)
1172 {
1173         struct sched_domain *sd;
1174 
1175         for_each_domain(cpu, sd) {
1176                 if (sd->flags & flag)
1177                         break;
1178         }
1179 
1180         return sd;
1181 }
1182 
1183 DECLARE_PER_CPU(struct sched_domain *, sd_llc);
1184 DECLARE_PER_CPU(int, sd_llc_size);
1185 DECLARE_PER_CPU(int, sd_llc_id);
1186 DECLARE_PER_CPU(struct sched_domain_shared *, sd_llc_shared);
1187 DECLARE_PER_CPU(struct sched_domain *, sd_numa);
1188 DECLARE_PER_CPU(struct sched_domain *, sd_asym);
1189 
1190 struct sched_group_capacity {
1191         atomic_t                ref;
1192         /*
1193          * CPU capacity of this group, SCHED_CAPACITY_SCALE being max capacity
1194          * for a single CPU.
1195          */
1196         unsigned long           capacity;
1197         unsigned long           min_capacity;           /* Min per-CPU capacity in group */
1198         unsigned long           next_update;
1199         int                     imbalance;              /* XXX unrelated to capacity but shared group state */
1200 
1201 #ifdef CONFIG_SCHED_DEBUG
1202         int                     id;
1203 #endif
1204 
1205         unsigned long           cpumask[0];             /* Balance mask */
1206 };
1207 
1208 struct sched_group {
1209         struct sched_group      *next;                  /* Must be a circular list */
1210         atomic_t                ref;
1211 
1212         unsigned int            group_weight;
1213         struct sched_group_capacity *sgc;
1214         int                     asym_prefer_cpu;        /* CPU of highest priority in group */
1215 
1216         /*
1217          * The CPUs this group covers.
1218          *
1219          * NOTE: this field is variable length. (Allocated dynamically
1220          * by attaching extra space to the end of the structure,
1221          * depending on how many CPUs the kernel has booted up with)
1222          */
1223         unsigned long           cpumask[0];
1224 };
1225 
1226 static inline struct cpumask *sched_group_span(struct sched_group *sg)
1227 {
1228         return to_cpumask(sg->cpumask);
1229 }
1230 
1231 /*
1232  * See build_balance_mask().
1233  */
1234 static inline struct cpumask *group_balance_mask(struct sched_group *sg)
1235 {
1236         return to_cpumask(sg->sgc->cpumask);
1237 }
1238 
1239 /**
1240  * group_first_cpu - Returns the first CPU in the cpumask of a sched_group.
1241  * @group: The group whose first CPU is to be returned.
1242  */
1243 static inline unsigned int group_first_cpu(struct sched_group *group)
1244 {
1245         return cpumask_first(sched_group_span(group));
1246 }
1247 
1248 extern int group_balance_cpu(struct sched_group *sg);
1249 
1250 #if defined(CONFIG_SCHED_DEBUG) && defined(CONFIG_SYSCTL)
1251 void register_sched_domain_sysctl(void);
1252 void dirty_sched_domain_sysctl(int cpu);
1253 void unregister_sched_domain_sysctl(void);
1254 #else
1255 static inline void register_sched_domain_sysctl(void)
1256 {
1257 }
1258 static inline void dirty_sched_domain_sysctl(int cpu)
1259 {
1260 }
1261 static inline void unregister_sched_domain_sysctl(void)
1262 {
1263 }
1264 #endif
1265 
1266 #else
1267 
1268 static inline void sched_ttwu_pending(void) { }
1269 
1270 #endif /* CONFIG_SMP */
1271 
1272 #include "stats.h"
1273 #include "autogroup.h"
1274 
1275 #ifdef CONFIG_CGROUP_SCHED
1276 
1277 /*
1278  * Return the group to which this tasks belongs.
1279  *
1280  * We cannot use task_css() and friends because the cgroup subsystem
1281  * changes that value before the cgroup_subsys::attach() method is called,
1282  * therefore we cannot pin it and might observe the wrong value.
1283  *
1284  * The same is true for autogroup's p->signal->autogroup->tg, the autogroup
1285  * core changes this before calling sched_move_task().
1286  *
1287  * Instead we use a 'copy' which is updated from sched_move_task() while
1288  * holding both task_struct::pi_lock and rq::lock.
1289  */
1290 static inline struct task_group *task_group(struct task_struct *p)
1291 {
1292         return p->sched_task_group;
1293 }
1294 
1295 /* Change a task's cfs_rq and parent entity if it moves across CPUs/groups */
1296 static inline void set_task_rq(struct task_struct *p, unsigned int cpu)
1297 {
1298 #if defined(CONFIG_FAIR_GROUP_SCHED) || defined(CONFIG_RT_GROUP_SCHED)
1299         struct task_group *tg = task_group(p);
1300 #endif
1301 
1302 #ifdef CONFIG_FAIR_GROUP_SCHED
1303         set_task_rq_fair(&p->se, p->se.cfs_rq, tg->cfs_rq[cpu]);
1304         p->se.cfs_rq = tg->cfs_rq[cpu];
1305         p->se.parent = tg->se[cpu];
1306 #endif
1307 
1308 #ifdef CONFIG_RT_GROUP_SCHED
1309         p->rt.rt_rq  = tg->rt_rq[cpu];
1310         p->rt.parent = tg->rt_se[cpu];
1311 #endif
1312 }
1313 
1314 #else /* CONFIG_CGROUP_SCHED */
1315 
1316 static inline void set_task_rq(struct task_struct *p, unsigned int cpu) { }
1317 static inline struct task_group *task_group(struct task_struct *p)
1318 {
1319         return NULL;
1320 }
1321 
1322 #endif /* CONFIG_CGROUP_SCHED */
1323 
1324 static inline void __set_task_cpu(struct task_struct *p, unsigned int cpu)
1325 {
1326         set_task_rq(p, cpu);
1327 #ifdef CONFIG_SMP
1328         /*
1329          * After ->cpu is set up to a new value, task_rq_lock(p, ...) can be
1330          * successfuly executed on another CPU. We must ensure that updates of
1331          * per-task data have been completed by this moment.
1332          */
1333         smp_wmb();
1334 #ifdef CONFIG_THREAD_INFO_IN_TASK
1335         p->cpu = cpu;
1336 #else
1337         task_thread_info(p)->cpu = cpu;
1338 #endif
1339         p->wake_cpu = cpu;
1340 #endif
1341 }
1342 
1343 /*
1344  * Tunables that become constants when CONFIG_SCHED_DEBUG is off:
1345  */
1346 #ifdef CONFIG_SCHED_DEBUG
1347 # include <linux/static_key.h>
1348 # define const_debug __read_mostly
1349 #else
1350 # define const_debug const
1351 #endif
1352 
1353 #define SCHED_FEAT(name, enabled)       \
1354         __SCHED_FEAT_##name ,
1355 
1356 enum {
1357 #include "features.h"
1358         __SCHED_FEAT_NR,
1359 };
1360 
1361 #undef SCHED_FEAT
1362 
1363 #if defined(CONFIG_SCHED_DEBUG) && defined(HAVE_JUMP_LABEL)
1364 
1365 /*
1366  * To support run-time toggling of sched features, all the translation units
1367  * (but core.c) reference the sysctl_sched_features defined in core.c.
1368  */
1369 extern const_debug unsigned int sysctl_sched_features;
1370 
1371 #define SCHED_FEAT(name, enabled)                                       \
1372 static __always_inline bool static_branch_##name(struct static_key *key) \
1373 {                                                                       \
1374         return static_key_##enabled(key);                               \
1375 }
1376 
1377 #include "features.h"
1378 #undef SCHED_FEAT
1379 
1380 extern struct static_key sched_feat_keys[__SCHED_FEAT_NR];
1381 #define sched_feat(x) (static_branch_##x(&sched_feat_keys[__SCHED_FEAT_##x]))
1382 
1383 #else /* !(SCHED_DEBUG && HAVE_JUMP_LABEL) */
1384 
1385 /*
1386  * Each translation unit has its own copy of sysctl_sched_features to allow
1387  * constants propagation at compile time and compiler optimization based on
1388  * features default.
1389  */
1390 #define SCHED_FEAT(name, enabled)       \
1391         (1UL << __SCHED_FEAT_##name) * enabled |
1392 static const_debug __maybe_unused unsigned int sysctl_sched_features =
1393 #include "features.h"
1394         0;
1395 #undef SCHED_FEAT
1396 
1397 #define sched_feat(x) (sysctl_sched_features & (1UL << __SCHED_FEAT_##x))
1398 
1399 #endif /* SCHED_DEBUG && HAVE_JUMP_LABEL */
1400 
1401 extern struct static_key_false sched_numa_balancing;
1402 extern struct static_key_false sched_schedstats;
1403 
1404 static inline u64 global_rt_period(void)
1405 {
1406         return (u64)sysctl_sched_rt_period * NSEC_PER_USEC;
1407 }
1408 
1409 static inline u64 global_rt_runtime(void)
1410 {
1411         if (sysctl_sched_rt_runtime < 0)
1412                 return RUNTIME_INF;
1413 
1414         return (u64)sysctl_sched_rt_runtime * NSEC_PER_USEC;
1415 }
1416 
1417 static inline int task_current(struct rq *rq, struct task_struct *p)
1418 {
1419         return rq->curr == p;
1420 }
1421 
1422 static inline int task_running(struct rq *rq, struct task_struct *p)
1423 {
1424 #ifdef CONFIG_SMP
1425         return p->on_cpu;
1426 #else
1427         return task_current(rq, p);
1428 #endif
1429 }
1430 
1431 static inline int task_on_rq_queued(struct task_struct *p)
1432 {
1433         return p->on_rq == TASK_ON_RQ_QUEUED;
1434 }
1435 
1436 static inline int task_on_rq_migrating(struct task_struct *p)
1437 {
1438         return p->on_rq == TASK_ON_RQ_MIGRATING;
1439 }
1440 
1441 /*
1442  * wake flags
1443  */
1444 #define WF_SYNC                 0x01            /* Waker goes to sleep after wakeup */
1445 #define WF_FORK                 0x02            /* Child wakeup after fork */
1446 #define WF_MIGRATED             0x4             /* Internal use, task got migrated */
1447 
1448 /*
1449  * To aid in avoiding the subversion of "niceness" due to uneven distribution
1450  * of tasks with abnormal "nice" values across CPUs the contribution that
1451  * each task makes to its run queue's load is weighted according to its
1452  * scheduling class and "nice" value. For SCHED_NORMAL tasks this is just a
1453  * scaled version of the new time slice allocation that they receive on time
1454  * slice expiry etc.
1455  */
1456 
1457 #define WEIGHT_IDLEPRIO         3
1458 #define WMULT_IDLEPRIO          1431655765
1459 
1460 extern const int                sched_prio_to_weight[40];
1461 extern const u32                sched_prio_to_wmult[40];
1462 
1463 /*
1464  * {de,en}queue flags:
1465  *
1466  * DEQUEUE_SLEEP  - task is no longer runnable
1467  * ENQUEUE_WAKEUP - task just became runnable
1468  *
1469  * SAVE/RESTORE - an otherwise spurious dequeue/enqueue, done to ensure tasks
1470  *                are in a known state which allows modification. Such pairs
1471  *                should preserve as much state as possible.
1472  *
1473  * MOVE - paired with SAVE/RESTORE, explicitly does not preserve the location
1474  *        in the runqueue.
1475  *
1476  * ENQUEUE_HEAD      - place at front of runqueue (tail if not specified)
1477  * ENQUEUE_REPLENISH - CBS (replenish runtime and postpone deadline)
1478  * ENQUEUE_MIGRATED  - the task was migrated during wakeup
1479  *
1480  */
1481 
1482 #define DEQUEUE_SLEEP           0x01
1483 #define DEQUEUE_SAVE            0x02 /* Matches ENQUEUE_RESTORE */
1484 #define DEQUEUE_MOVE            0x04 /* Matches ENQUEUE_MOVE */
1485 #define DEQUEUE_NOCLOCK         0x08 /* Matches ENQUEUE_NOCLOCK */
1486 
1487 #define ENQUEUE_WAKEUP          0x01
1488 #define ENQUEUE_RESTORE         0x02
1489 #define ENQUEUE_MOVE            0x04
1490 #define ENQUEUE_NOCLOCK         0x08
1491 
1492 #define ENQUEUE_HEAD            0x10
1493 #define ENQUEUE_REPLENISH       0x20
1494 #ifdef CONFIG_SMP
1495 #define ENQUEUE_MIGRATED        0x40
1496 #else
1497 #define ENQUEUE_MIGRATED        0x00
1498 #endif
1499 
1500 #define RETRY_TASK              ((void *)-1UL)
1501 
1502 struct sched_class {
1503         const struct sched_class *next;
1504 
1505         void (*enqueue_task) (struct rq *rq, struct task_struct *p, int flags);
1506         void (*dequeue_task) (struct rq *rq, struct task_struct *p, int flags);
1507         void (*yield_task)   (struct rq *rq);
1508         bool (*yield_to_task)(struct rq *rq, struct task_struct *p, bool preempt);
1509 
1510         void (*check_preempt_curr)(struct rq *rq, struct task_struct *p, int flags);
1511 
1512         /*
1513          * It is the responsibility of the pick_next_task() method that will
1514          * return the next task to call put_prev_task() on the @prev task or
1515          * something equivalent.
1516          *
1517          * May return RETRY_TASK when it finds a higher prio class has runnable
1518          * tasks.
1519          */
1520         struct task_struct * (*pick_next_task)(struct rq *rq,
1521                                                struct task_struct *prev,
1522                                                struct rq_flags *rf);
1523         void (*put_prev_task)(struct rq *rq, struct task_struct *p);
1524 
1525 #ifdef CONFIG_SMP
1526         int  (*select_task_rq)(struct task_struct *p, int task_cpu, int sd_flag, int flags);
1527         void (*migrate_task_rq)(struct task_struct *p, int new_cpu);
1528 
1529         void (*task_woken)(struct rq *this_rq, struct task_struct *task);
1530 
1531         void (*set_cpus_allowed)(struct task_struct *p,
1532                                  const struct cpumask *newmask);
1533 
1534         void (*rq_online)(struct rq *rq);
1535         void (*rq_offline)(struct rq *rq);
1536 #endif
1537 
1538         void (*set_curr_task)(struct rq *rq);
1539         void (*task_tick)(struct rq *rq, struct task_struct *p, int queued);
1540         void (*task_fork)(struct task_struct *p);
1541         void (*task_dead)(struct task_struct *p);
1542 
1543         /*
1544          * The switched_from() call is allowed to drop rq->lock, therefore we
1545          * cannot assume the switched_from/switched_to pair is serliazed by
1546          * rq->lock. They are however serialized by p->pi_lock.
1547          */
1548         void (*switched_from)(struct rq *this_rq, struct task_struct *task);
1549         void (*switched_to)  (struct rq *this_rq, struct task_struct *task);
1550         void (*prio_changed) (struct rq *this_rq, struct task_struct *task,
1551                               int oldprio);
1552 
1553         unsigned int (*get_rr_interval)(struct rq *rq,
1554                                         struct task_struct *task);
1555 
1556         void (*update_curr)(struct rq *rq);
1557 
1558 #define TASK_SET_GROUP          0
1559 #define TASK_MOVE_GROUP         1
1560 
1561 #ifdef CONFIG_FAIR_GROUP_SCHED
1562         void (*task_change_group)(struct task_struct *p, int type);
1563 #endif
1564 };
1565 
1566 static inline void put_prev_task(struct rq *rq, struct task_struct *prev)
1567 {
1568         prev->sched_class->put_prev_task(rq, prev);
1569 }
1570 
1571 static inline void set_curr_task(struct rq *rq, struct task_struct *curr)
1572 {
1573         curr->sched_class->set_curr_task(rq);
1574 }
1575 
1576 #ifdef CONFIG_SMP
1577 #define sched_class_highest (&stop_sched_class)
1578 #else
1579 #define sched_class_highest (&dl_sched_class)
1580 #endif
1581 #define for_each_class(class) \
1582    for (class = sched_class_highest; class; class = class->next)
1583 
1584 extern const struct sched_class stop_sched_class;
1585 extern const struct sched_class dl_sched_class;
1586 extern const struct sched_class rt_sched_class;
1587 extern const struct sched_class fair_sched_class;
1588 extern const struct sched_class idle_sched_class;
1589 
1590 
1591 #ifdef CONFIG_SMP
1592 
1593 extern void update_group_capacity(struct sched_domain *sd, int cpu);
1594 
1595 extern void trigger_load_balance(struct rq *rq);
1596 
1597 extern void set_cpus_allowed_common(struct task_struct *p, const struct cpumask *new_mask);
1598 
1599 #endif
1600 
1601 #ifdef CONFIG_CPU_IDLE
1602 static inline void idle_set_state(struct rq *rq,
1603                                   struct cpuidle_state *idle_state)
1604 {
1605         rq->idle_state = idle_state;
1606 }
1607 
1608 static inline struct cpuidle_state *idle_get_state(struct rq *rq)
1609 {
1610         SCHED_WARN_ON(!rcu_read_lock_held());
1611 
1612         return rq->idle_state;
1613 }
1614 #else
1615 static inline void idle_set_state(struct rq *rq,
1616                                   struct cpuidle_state *idle_state)
1617 {
1618 }
1619 
1620 static inline struct cpuidle_state *idle_get_state(struct rq *rq)
1621 {
1622         return NULL;
1623 }
1624 #endif
1625 
1626 extern void schedule_idle(void);
1627 
1628 extern void sysrq_sched_debug_show(void);
1629 extern void sched_init_granularity(void);
1630 extern void update_max_interval(void);
1631 
1632 extern void init_sched_dl_class(void);
1633 extern void init_sched_rt_class(void);
1634 extern void init_sched_fair_class(void);
1635 
1636 extern void reweight_task(struct task_struct *p, int prio);
1637 
1638 extern void resched_curr(struct rq *rq);
1639 extern void resched_cpu(int cpu);
1640 
1641 extern struct rt_bandwidth def_rt_bandwidth;
1642 extern void init_rt_bandwidth(struct rt_bandwidth *rt_b, u64 period, u64 runtime);
1643 
1644 extern struct dl_bandwidth def_dl_bandwidth;
1645 extern void init_dl_bandwidth(struct dl_bandwidth *dl_b, u64 period, u64 runtime);
1646 extern void init_dl_task_timer(struct sched_dl_entity *dl_se);
1647 extern void init_dl_inactive_task_timer(struct sched_dl_entity *dl_se);
1648 extern void init_dl_rq_bw_ratio(struct dl_rq *dl_rq);
1649 
1650 #define BW_SHIFT                20
1651 #define BW_UNIT                 (1 << BW_SHIFT)
1652 #define RATIO_SHIFT             8
1653 unsigned long to_ratio(u64 period, u64 runtime);
1654 
1655 extern void init_entity_runnable_average(struct sched_entity *se);
1656 extern void post_init_entity_util_avg(struct sched_entity *se);
1657 
1658 #ifdef CONFIG_NO_HZ_FULL
1659 extern bool sched_can_stop_tick(struct rq *rq);
1660 extern int __init sched_tick_offload_init(void);
1661 
1662 /*
1663  * Tick may be needed by tasks in the runqueue depending on their policy and
1664  * requirements. If tick is needed, lets send the target an IPI to kick it out of
1665  * nohz mode if necessary.
1666  */
1667 static inline void sched_update_tick_dependency(struct rq *rq)
1668 {
1669         int cpu;
1670 
1671         if (!tick_nohz_full_enabled())
1672                 return;
1673 
1674         cpu = cpu_of(rq);
1675 
1676         if (!tick_nohz_full_cpu(cpu))
1677                 return;
1678 
1679         if (sched_can_stop_tick(rq))
1680                 tick_nohz_dep_clear_cpu(cpu, TICK_DEP_BIT_SCHED);
1681         else
1682                 tick_nohz_dep_set_cpu(cpu, TICK_DEP_BIT_SCHED);
1683 }
1684 #else
1685 static inline int sched_tick_offload_init(void) { return 0; }
1686 static inline void sched_update_tick_dependency(struct rq *rq) { }
1687 #endif
1688 
1689 static inline void add_nr_running(struct rq *rq, unsigned count)
1690 {
1691         unsigned prev_nr = rq->nr_running;
1692 
1693         rq->nr_running = prev_nr + count;
1694 
1695         if (prev_nr < 2 && rq->nr_running >= 2) {
1696 #ifdef CONFIG_SMP
1697                 if (!rq->rd->overload)
1698                         rq->rd->overload = true;
1699 #endif
1700         }
1701 
1702         sched_update_tick_dependency(rq);
1703 }
1704 
1705 static inline void sub_nr_running(struct rq *rq, unsigned count)
1706 {
1707         rq->nr_running -= count;
1708         /* Check if we still need preemption */
1709         sched_update_tick_dependency(rq);
1710 }
1711 
1712 extern void update_rq_clock(struct rq *rq);
1713 
1714 extern void activate_task(struct rq *rq, struct task_struct *p, int flags);
1715 extern void deactivate_task(struct rq *rq, struct task_struct *p, int flags);
1716 
1717 extern void check_preempt_curr(struct rq *rq, struct task_struct *p, int flags);
1718 
1719 extern const_debug unsigned int sysctl_sched_nr_migrate;
1720 extern const_debug unsigned int sysctl_sched_migration_cost;
1721 
1722 #ifdef CONFIG_SCHED_HRTICK
1723 
1724 /*
1725  * Use hrtick when:
1726  *  - enabled by features
1727  *  - hrtimer is actually high res
1728  */
1729 static inline int hrtick_enabled(struct rq *rq)
1730 {
1731         if (!sched_feat(HRTICK))
1732                 return 0;
1733         if (!cpu_active(cpu_of(rq)))
1734                 return 0;
1735         return hrtimer_is_hres_active(&rq->hrtick_timer);
1736 }
1737 
1738 void hrtick_start(struct rq *rq, u64 delay);
1739 
1740 #else
1741 
1742 static inline int hrtick_enabled(struct rq *rq)
1743 {
1744         return 0;
1745 }
1746 
1747 #endif /* CONFIG_SCHED_HRTICK */
1748 
1749 #ifndef arch_scale_freq_capacity
1750 static __always_inline
1751 unsigned long arch_scale_freq_capacity(int cpu)
1752 {
1753         return SCHED_CAPACITY_SCALE;
1754 }
1755 #endif
1756 
1757 #ifdef CONFIG_SMP
1758 #ifndef arch_scale_cpu_capacity
1759 static __always_inline
1760 unsigned long arch_scale_cpu_capacity(struct sched_domain *sd, int cpu)
1761 {
1762         if (sd && (sd->flags & SD_SHARE_CPUCAPACITY) && (sd->span_weight > 1))
1763                 return sd->smt_gain / sd->span_weight;
1764 
1765         return SCHED_CAPACITY_SCALE;
1766 }
1767 #endif
1768 #else
1769 #ifndef arch_scale_cpu_capacity
1770 static __always_inline
1771 unsigned long arch_scale_cpu_capacity(void __always_unused *sd, int cpu)
1772 {
1773         return SCHED_CAPACITY_SCALE;
1774 }
1775 #endif
1776 #endif
1777 
1778 struct rq *__task_rq_lock(struct task_struct *p, struct rq_flags *rf)
1779         __acquires(rq->lock);
1780 
1781 struct rq *task_rq_lock(struct task_struct *p, struct rq_flags *rf)
1782         __acquires(p->pi_lock)
1783         __acquires(rq->lock);
1784 
1785 static inline void __task_rq_unlock(struct rq *rq, struct rq_flags *rf)
1786         __releases(rq->lock)
1787 {
1788         rq_unpin_lock(rq, rf);
1789         raw_spin_unlock(&rq->lock);
1790 }
1791 
1792 static inline void
1793 task_rq_unlock(struct rq *rq, struct task_struct *p, struct rq_flags *rf)
1794         __releases(rq->lock)
1795         __releases(p->pi_lock)
1796 {
1797         rq_unpin_lock(rq, rf);
1798         raw_spin_unlock(&rq->lock);
1799         raw_spin_unlock_irqrestore(&p->pi_lock, rf->flags);
1800 }
1801 
1802 static inline void
1803 rq_lock_irqsave(struct rq *rq, struct rq_flags *rf)
1804         __acquires(rq->lock)
1805 {
1806         raw_spin_lock_irqsave(&rq->lock, rf->flags);
1807         rq_pin_lock(rq, rf);
1808 }
1809 
1810 static inline void
1811 rq_lock_irq(struct rq *rq, struct rq_flags *rf)
1812         __acquires(rq->lock)
1813 {
1814         raw_spin_lock_irq(&rq->lock);
1815         rq_pin_lock(rq, rf);
1816 }
1817 
1818 static inline void
1819 rq_lock(struct rq *rq, struct rq_flags *rf)
1820         __acquires(rq->lock)
1821 {
1822         raw_spin_lock(&rq->lock);
1823         rq_pin_lock(rq, rf);
1824 }
1825 
1826 static inline void
1827 rq_relock(struct rq *rq, struct rq_flags *rf)
1828         __acquires(rq->lock)
1829 {
1830         raw_spin_lock(&rq->lock);
1831         rq_repin_lock(rq, rf);
1832 }
1833 
1834 static inline void
1835 rq_unlock_irqrestore(struct rq *rq, struct rq_flags *rf)
1836         __releases(rq->lock)
1837 {
1838         rq_unpin_lock(rq, rf);
1839         raw_spin_unlock_irqrestore(&rq->lock, rf->flags);
1840 }
1841 
1842 static inline void
1843 rq_unlock_irq(struct rq *rq, struct rq_flags *rf)
1844         __releases(rq->lock)
1845 {
1846         rq_unpin_lock(rq, rf);
1847         raw_spin_unlock_irq(&rq->lock);
1848 }
1849 
1850 static inline void
1851 rq_unlock(struct rq *rq, struct rq_flags *rf)
1852         __releases(rq->lock)
1853 {
1854         rq_unpin_lock(rq, rf);
1855         raw_spin_unlock(&rq->lock);
1856 }
1857 
1858 #ifdef CONFIG_SMP
1859 #ifdef CONFIG_PREEMPT
1860 
1861 static inline void double_rq_lock(struct rq *rq1, struct rq *rq2);
1862 
1863 /*
1864  * fair double_lock_balance: Safely acquires both rq->locks in a fair
1865  * way at the expense of forcing extra atomic operations in all
1866  * invocations.  This assures that the double_lock is acquired using the
1867  * same underlying policy as the spinlock_t on this architecture, which
1868  * reduces latency compared to the unfair variant below.  However, it
1869  * also adds more overhead and therefore may reduce throughput.
1870  */
1871 static inline int _double_lock_balance(struct rq *this_rq, struct rq *busiest)
1872         __releases(this_rq->lock)
1873         __acquires(busiest->lock)
1874         __acquires(this_rq->lock)
1875 {
1876         raw_spin_unlock(&this_rq->lock);
1877         double_rq_lock(this_rq, busiest);
1878 
1879         return 1;
1880 }
1881 
1882 #else
1883 /*
1884  * Unfair double_lock_balance: Optimizes throughput at the expense of
1885  * latency by eliminating extra atomic operations when the locks are
1886  * already in proper order on entry.  This favors lower CPU-ids and will
1887  * grant the double lock to lower CPUs over higher ids under contention,
1888  * regardless of entry order into the function.
1889  */
1890 static inline int _double_lock_balance(struct rq *this_rq, struct rq *busiest)
1891         __releases(this_rq->lock)
1892         __acquires(busiest->lock)
1893         __acquires(this_rq->lock)
1894 {
1895         int ret = 0;
1896 
1897         if (unlikely(!raw_spin_trylock(&busiest->lock))) {
1898                 if (busiest < this_rq) {
1899                         raw_spin_unlock(&this_rq->lock);
1900                         raw_spin_lock(&busiest->lock);
1901                         raw_spin_lock_nested(&this_rq->lock,
1902                                               SINGLE_DEPTH_NESTING);
1903                         ret = 1;
1904                 } else
1905                         raw_spin_lock_nested(&busiest->lock,
1906                                               SINGLE_DEPTH_NESTING);
1907         }
1908         return ret;
1909 }
1910 
1911 #endif /* CONFIG_PREEMPT */
1912 
1913 /*
1914  * double_lock_balance - lock the busiest runqueue, this_rq is locked already.
1915  */
1916 static inline int double_lock_balance(struct rq *this_rq, struct rq *busiest)
1917 {
1918         if (unlikely(!irqs_disabled())) {
1919                 /* printk() doesn't work well under rq->lock */
1920                 raw_spin_unlock(&this_rq->lock);
1921                 BUG_ON(1);
1922         }
1923 
1924         return _double_lock_balance(this_rq, busiest);
1925 }
1926 
1927 static inline void double_unlock_balance(struct rq *this_rq, struct rq *busiest)
1928         __releases(busiest->lock)
1929 {
1930         raw_spin_unlock(&busiest->lock);
1931         lock_set_subclass(&this_rq->lock.dep_map, 0, _RET_IP_);
1932 }
1933 
1934 static inline void double_lock(spinlock_t *l1, spinlock_t *l2)
1935 {
1936         if (l1 > l2)
1937                 swap(l1, l2);
1938 
1939         spin_lock(l1);
1940         spin_lock_nested(l2, SINGLE_DEPTH_NESTING);
1941 }
1942 
1943 static inline void double_lock_irq(spinlock_t *l1, spinlock_t *l2)
1944 {
1945         if (l1 > l2)
1946                 swap(l1, l2);
1947 
1948         spin_lock_irq(l1);
1949         spin_lock_nested(l2, SINGLE_DEPTH_NESTING);
1950 }
1951 
1952 static inline void double_raw_lock(raw_spinlock_t *l1, raw_spinlock_t *l2)
1953 {
1954         if (l1 > l2)
1955                 swap(l1, l2);
1956 
1957         raw_spin_lock(l1);
1958         raw_spin_lock_nested(l2, SINGLE_DEPTH_NESTING);
1959 }
1960 
1961 /*
1962  * double_rq_lock - safely lock two runqueues
1963  *
1964  * Note this does not disable interrupts like task_rq_lock,
1965  * you need to do so manually before calling.
1966  */
1967 static inline void double_rq_lock(struct rq *rq1, struct rq *rq2)
1968         __acquires(rq1->lock)
1969         __acquires(rq2->lock)
1970 {
1971         BUG_ON(!irqs_disabled());
1972         if (rq1 == rq2) {
1973                 raw_spin_lock(&rq1->lock);
1974                 __acquire(rq2->lock);   /* Fake it out ;) */
1975         } else {
1976                 if (rq1 < rq2) {
1977                         raw_spin_lock(&rq1->lock);
1978                         raw_spin_lock_nested(&rq2->lock, SINGLE_DEPTH_NESTING);
1979                 } else {
1980                         raw_spin_lock(&rq2->lock);
1981                         raw_spin_lock_nested(&rq1->lock, SINGLE_DEPTH_NESTING);
1982                 }
1983         }
1984 }
1985 
1986 /*
1987  * double_rq_unlock - safely unlock two runqueues
1988  *
1989  * Note this does not restore interrupts like task_rq_unlock,
1990  * you need to do so manually after calling.
1991  */
1992 static inline void double_rq_unlock(struct rq *rq1, struct rq *rq2)
1993         __releases(rq1->lock)
1994         __releases(rq2->lock)
1995 {
1996         raw_spin_unlock(&rq1->lock);
1997         if (rq1 != rq2)
1998                 raw_spin_unlock(&rq2->lock);
1999         else
2000                 __release(rq2->lock);
2001 }
2002 
2003 extern void set_rq_online (struct rq *rq);
2004 extern void set_rq_offline(struct rq *rq);
2005 extern bool sched_smp_initialized;
2006 
2007 #else /* CONFIG_SMP */
2008 
2009 /*
2010  * double_rq_lock - safely lock two runqueues
2011  *
2012  * Note this does not disable interrupts like task_rq_lock,
2013  * you need to do so manually before calling.
2014  */
2015 static inline void double_rq_lock(struct rq *rq1, struct rq *rq2)
2016         __acquires(rq1->lock)
2017         __acquires(rq2->lock)
2018 {
2019         BUG_ON(!irqs_disabled());
2020         BUG_ON(rq1 != rq2);
2021         raw_spin_lock(&rq1->lock);
2022         __acquire(rq2->lock);   /* Fake it out ;) */
2023 }
2024 
2025 /*
2026  * double_rq_unlock - safely unlock two runqueues
2027  *
2028  * Note this does not restore interrupts like task_rq_unlock,
2029  * you need to do so manually after calling.
2030  */
2031 static inline void double_rq_unlock(struct rq *rq1, struct rq *rq2)
2032         __releases(rq1->lock)
2033         __releases(rq2->lock)
2034 {
2035         BUG_ON(rq1 != rq2);
2036         raw_spin_unlock(&rq1->lock);
2037         __release(rq2->lock);
2038 }
2039 
2040 #endif
2041 
2042 extern struct sched_entity *__pick_first_entity(struct cfs_rq *cfs_rq);
2043 extern struct sched_entity *__pick_last_entity(struct cfs_rq *cfs_rq);
2044 
2045 #ifdef  CONFIG_SCHED_DEBUG
2046 extern bool sched_debug_enabled;
2047 
2048 extern void print_cfs_stats(struct seq_file *m, int cpu);
2049 extern void print_rt_stats(struct seq_file *m, int cpu);
2050 extern void print_dl_stats(struct seq_file *m, int cpu);
2051 extern void print_cfs_rq(struct seq_file *m, int cpu, struct cfs_rq *cfs_rq);
2052 extern void print_rt_rq(struct seq_file *m, int cpu, struct rt_rq *rt_rq);
2053 extern void print_dl_rq(struct seq_file *m, int cpu, struct dl_rq *dl_rq);
2054 #ifdef CONFIG_NUMA_BALANCING
2055 extern void
2056 show_numa_stats(struct task_struct *p, struct seq_file *m);
2057 extern void
2058 print_numa_stats(struct seq_file *m, int node, unsigned long tsf,
2059         unsigned long tpf, unsigned long gsf, unsigned long gpf);
2060 #endif /* CONFIG_NUMA_BALANCING */
2061 #endif /* CONFIG_SCHED_DEBUG */
2062 
2063 extern void init_cfs_rq(struct cfs_rq *cfs_rq);
2064 extern void init_rt_rq(struct rt_rq *rt_rq);
2065 extern void init_dl_rq(struct dl_rq *dl_rq);
2066 
2067 extern void cfs_bandwidth_usage_inc(void);
2068 extern void cfs_bandwidth_usage_dec(void);
2069 
2070 #ifdef CONFIG_NO_HZ_COMMON
2071 #define NOHZ_BALANCE_KICK_BIT   0
2072 #define NOHZ_STATS_KICK_BIT     1
2073 
2074 #define NOHZ_BALANCE_KICK       BIT(NOHZ_BALANCE_KICK_BIT)
2075 #define NOHZ_STATS_KICK         BIT(NOHZ_STATS_KICK_BIT)
2076 
2077 #define NOHZ_KICK_MASK  (NOHZ_BALANCE_KICK | NOHZ_STATS_KICK)
2078 
2079 #define nohz_flags(cpu) (&cpu_rq(cpu)->nohz_flags)
2080 
2081 extern void nohz_balance_exit_idle(struct rq *rq);
2082 #else
2083 static inline void nohz_balance_exit_idle(struct rq *rq) { }
2084 #endif
2085 
2086 
2087 #ifdef CONFIG_SMP
2088 static inline
2089 void __dl_update(struct dl_bw *dl_b, s64 bw)
2090 {
2091         struct root_domain *rd = container_of(dl_b, struct root_domain, dl_bw);
2092         int i;
2093 
2094         RCU_LOCKDEP_WARN(!rcu_read_lock_sched_held(),
2095                          "sched RCU must be held");
2096         for_each_cpu_and(i, rd->span, cpu_active_mask) {
2097                 struct rq *rq = cpu_rq(i);
2098 
2099                 rq->dl.extra_bw += bw;
2100         }
2101 }
2102 #else
2103 static inline
2104 void __dl_update(struct dl_bw *dl_b, s64 bw)
2105 {
2106         struct dl_rq *dl = container_of(dl_b, struct dl_rq, dl_bw);
2107 
2108         dl->extra_bw += bw;
2109 }
2110 #endif
2111 
2112 
2113 #ifdef CONFIG_IRQ_TIME_ACCOUNTING
2114 struct irqtime {
2115         u64                     total;
2116         u64                     tick_delta;
2117         u64                     irq_start_time;
2118         struct u64_stats_sync   sync;
2119 };
2120 
2121 DECLARE_PER_CPU(struct irqtime, cpu_irqtime);
2122 
2123 /*
2124  * Returns the irqtime minus the softirq time computed by ksoftirqd.
2125  * Otherwise ksoftirqd's sum_exec_runtime is substracted its own runtime
2126  * and never move forward.
2127  */
2128 static inline u64 irq_time_read(int cpu)
2129 {
2130         struct irqtime *irqtime = &per_cpu(cpu_irqtime, cpu);
2131         unsigned int seq;
2132         u64 total;
2133 
2134         do {
2135                 seq = __u64_stats_fetch_begin(&irqtime->sync);
2136                 total = irqtime->total;
2137         } while (__u64_stats_fetch_retry(&irqtime->sync, seq));
2138 
2139         return total;
2140 }
2141 #endif /* CONFIG_IRQ_TIME_ACCOUNTING */
2142 
2143 #ifdef CONFIG_CPU_FREQ
2144 DECLARE_PER_CPU(struct update_util_data *, cpufreq_update_util_data);
2145 
2146 /**
2147  * cpufreq_update_util - Take a note about CPU utilization changes.
2148  * @rq: Runqueue to carry out the update for.
2149  * @flags: Update reason flags.
2150  *
2151  * This function is called by the scheduler on the CPU whose utilization is
2152  * being updated.
2153  *
2154  * It can only be called from RCU-sched read-side critical sections.
2155  *
2156  * The way cpufreq is currently arranged requires it to evaluate the CPU
2157  * performance state (frequency/voltage) on a regular basis to prevent it from
2158  * being stuck in a completely inadequate performance level for too long.
2159  * That is not guaranteed to happen if the updates are only triggered from CFS
2160  * and DL, though, because they may not be coming in if only RT tasks are
2161  * active all the time (or there are RT tasks only).
2162  *
2163  * As a workaround for that issue, this function is called periodically by the
2164  * RT sched class to trigger extra cpufreq updates to prevent it from stalling,
2165  * but that really is a band-aid.  Going forward it should be replaced with
2166  * solutions targeted more specifically at RT tasks.
2167  */
2168 static inline void cpufreq_update_util(struct rq *rq, unsigned int flags)
2169 {
2170         struct update_util_data *data;
2171 
2172         data = rcu_dereference_sched(*per_cpu_ptr(&cpufreq_update_util_data,
2173                                                   cpu_of(rq)));
2174         if (data)
2175                 data->func(data, rq_clock(rq), flags);
2176 }
2177 #else
2178 static inline void cpufreq_update_util(struct rq *rq, unsigned int flags) {}
2179 #endif /* CONFIG_CPU_FREQ */
2180 
2181 #ifdef arch_scale_freq_capacity
2182 # ifndef arch_scale_freq_invariant
2183 #  define arch_scale_freq_invariant()   true
2184 # endif
2185 #else
2186 # define arch_scale_freq_invariant()    false
2187 #endif
2188 
2189 #ifdef CONFIG_CPU_FREQ_GOV_SCHEDUTIL
2190 static inline unsigned long cpu_bw_dl(struct rq *rq)
2191 {
2192         return (rq->dl.running_bw * SCHED_CAPACITY_SCALE) >> BW_SHIFT;
2193 }
2194 
2195 static inline unsigned long cpu_util_dl(struct rq *rq)
2196 {
2197         return READ_ONCE(rq->avg_dl.util_avg);
2198 }
2199 
2200 static inline unsigned long cpu_util_cfs(struct rq *rq)
2201 {
2202         unsigned long util = READ_ONCE(rq->cfs.avg.util_avg);
2203 
2204         if (sched_feat(UTIL_EST)) {
2205                 util = max_t(unsigned long, util,
2206                              READ_ONCE(rq->cfs.avg.util_est.enqueued));
2207         }
2208 
2209         return util;
2210 }
2211 
2212 static inline unsigned long cpu_util_rt(struct rq *rq)
2213 {
2214         return READ_ONCE(rq->avg_rt.util_avg);
2215 }
2216 #endif
2217 
2218 #ifdef HAVE_SCHED_AVG_IRQ
2219 static inline unsigned long cpu_util_irq(struct rq *rq)
2220 {
2221         return rq->avg_irq.util_avg;
2222 }
2223 
2224 static inline
2225 unsigned long scale_irq_capacity(unsigned long util, unsigned long irq, unsigned long max)
2226 {
2227         util *= (max - irq);
2228         util /= max;
2229 
2230         return util;
2231 
2232 }
2233 #else
2234 static inline unsigned long cpu_util_irq(struct rq *rq)
2235 {
2236         return 0;
2237 }
2238 
2239 static inline
2240 unsigned long scale_irq_capacity(unsigned long util, unsigned long irq, unsigned long max)
2241 {
2242         return util;
2243 }
2244 #endif
2245 

~ [ source navigation ] ~ [ diff markup ] ~ [ identifier search ] ~

kernel.org | git.kernel.org | LWN.net | Project Home | Wiki (Japanese) | Wiki (English) | SVN repository | Mail admin

Linux® is a registered trademark of Linus Torvalds in the United States and other countries.
TOMOYO® is a registered trademark of NTT DATA CORPORATION.

osdn.jp