1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3 * kernel/sched/debug.c
4 *
5 * Print the CFS rbtree and other debugging details
6 *
7 * Copyright(C) 2007, Red Hat, Inc., Ingo Molnar
8 */
9 #include <linux/debugfs.h>
10 #include <linux/nmi.h>
11 #include "sched.h"
12
13 /*
14 * This allows printing both to /sys/kernel/debug/sched/debug and
15 * to the console
16 */
17 #define SEQ_printf(m, x...) \
18 do { \
19 if (m) \
20 seq_printf(m, x); \
21 else \
22 pr_cont(x); \
23 } while (0)
24
25 /*
26 * Ease the printing of nsec fields:
27 */
nsec_high(unsigned long long nsec)28 static long long nsec_high(unsigned long long nsec)
29 {
30 if ((long long)nsec < 0) {
31 nsec = -nsec;
32 do_div(nsec, 1000000);
33 return -nsec;
34 }
35 do_div(nsec, 1000000);
36
37 return nsec;
38 }
39
nsec_low(unsigned long long nsec)40 static unsigned long nsec_low(unsigned long long nsec)
41 {
42 if ((long long)nsec < 0)
43 nsec = -nsec;
44
45 return do_div(nsec, 1000000);
46 }
47
48 #define SPLIT_NS(x) nsec_high(x), nsec_low(x)
49
50 #define SCHED_FEAT(name, enabled) \
51 #name ,
52
53 static const char * const sched_feat_names[] = {
54 #include "features.h"
55 };
56
57 #undef SCHED_FEAT
58
sched_feat_show(struct seq_file * m,void * v)59 static int sched_feat_show(struct seq_file *m, void *v)
60 {
61 int i;
62
63 for (i = 0; i < __SCHED_FEAT_NR; i++) {
64 if (!(sysctl_sched_features & (1UL << i)))
65 seq_puts(m, "NO_");
66 seq_printf(m, "%s ", sched_feat_names[i]);
67 }
68 seq_puts(m, "\n");
69
70 return 0;
71 }
72
73 #ifdef CONFIG_JUMP_LABEL
74
75 #define jump_label_key__true STATIC_KEY_INIT_TRUE
76 #define jump_label_key__false STATIC_KEY_INIT_FALSE
77
78 #define SCHED_FEAT(name, enabled) \
79 jump_label_key__##enabled ,
80
81 struct static_key sched_feat_keys[__SCHED_FEAT_NR] = {
82 #include "features.h"
83 };
84
85 #undef SCHED_FEAT
86
sched_feat_disable(int i)87 static void sched_feat_disable(int i)
88 {
89 static_key_disable_cpuslocked(&sched_feat_keys[i]);
90 }
91
sched_feat_enable(int i)92 static void sched_feat_enable(int i)
93 {
94 static_key_enable_cpuslocked(&sched_feat_keys[i]);
95 }
96 #else /* !CONFIG_JUMP_LABEL: */
sched_feat_disable(int i)97 static void sched_feat_disable(int i) { };
sched_feat_enable(int i)98 static void sched_feat_enable(int i) { };
99 #endif /* !CONFIG_JUMP_LABEL */
100
sched_feat_set(char * cmp)101 static int sched_feat_set(char *cmp)
102 {
103 int i;
104 int neg = 0;
105
106 if (strncmp(cmp, "NO_", 3) == 0) {
107 neg = 1;
108 cmp += 3;
109 }
110
111 i = match_string(sched_feat_names, __SCHED_FEAT_NR, cmp);
112 if (i < 0)
113 return i;
114
115 if (neg) {
116 sysctl_sched_features &= ~(1UL << i);
117 sched_feat_disable(i);
118 } else {
119 sysctl_sched_features |= (1UL << i);
120 sched_feat_enable(i);
121 }
122
123 return 0;
124 }
125
126 static ssize_t
sched_feat_write(struct file * filp,const char __user * ubuf,size_t cnt,loff_t * ppos)127 sched_feat_write(struct file *filp, const char __user *ubuf,
128 size_t cnt, loff_t *ppos)
129 {
130 char buf[64];
131 char *cmp;
132 int ret;
133 struct inode *inode;
134
135 if (cnt > 63)
136 cnt = 63;
137
138 if (copy_from_user(&buf, ubuf, cnt))
139 return -EFAULT;
140
141 buf[cnt] = 0;
142 cmp = strstrip(buf);
143
144 /* Ensure the static_key remains in a consistent state */
145 inode = file_inode(filp);
146 cpus_read_lock();
147 inode_lock(inode);
148 ret = sched_feat_set(cmp);
149 inode_unlock(inode);
150 cpus_read_unlock();
151 if (ret < 0)
152 return ret;
153
154 *ppos += cnt;
155
156 return cnt;
157 }
158
sched_feat_open(struct inode * inode,struct file * filp)159 static int sched_feat_open(struct inode *inode, struct file *filp)
160 {
161 return single_open(filp, sched_feat_show, NULL);
162 }
163
164 static const struct file_operations sched_feat_fops = {
165 .open = sched_feat_open,
166 .write = sched_feat_write,
167 .read = seq_read,
168 .llseek = seq_lseek,
169 .release = single_release,
170 };
171
sched_scaling_write(struct file * filp,const char __user * ubuf,size_t cnt,loff_t * ppos)172 static ssize_t sched_scaling_write(struct file *filp, const char __user *ubuf,
173 size_t cnt, loff_t *ppos)
174 {
175 char buf[16];
176 unsigned int scaling;
177
178 if (cnt > 15)
179 cnt = 15;
180
181 if (copy_from_user(&buf, ubuf, cnt))
182 return -EFAULT;
183 buf[cnt] = '\0';
184
185 if (kstrtouint(buf, 10, &scaling))
186 return -EINVAL;
187
188 if (scaling >= SCHED_TUNABLESCALING_END)
189 return -EINVAL;
190
191 sysctl_sched_tunable_scaling = scaling;
192 if (sched_update_scaling())
193 return -EINVAL;
194
195 *ppos += cnt;
196 return cnt;
197 }
198
sched_scaling_show(struct seq_file * m,void * v)199 static int sched_scaling_show(struct seq_file *m, void *v)
200 {
201 seq_printf(m, "%d\n", sysctl_sched_tunable_scaling);
202 return 0;
203 }
204
sched_scaling_open(struct inode * inode,struct file * filp)205 static int sched_scaling_open(struct inode *inode, struct file *filp)
206 {
207 return single_open(filp, sched_scaling_show, NULL);
208 }
209
210 static const struct file_operations sched_scaling_fops = {
211 .open = sched_scaling_open,
212 .write = sched_scaling_write,
213 .read = seq_read,
214 .llseek = seq_lseek,
215 .release = single_release,
216 };
217
218 #ifdef CONFIG_PREEMPT_DYNAMIC
219
sched_dynamic_write(struct file * filp,const char __user * ubuf,size_t cnt,loff_t * ppos)220 static ssize_t sched_dynamic_write(struct file *filp, const char __user *ubuf,
221 size_t cnt, loff_t *ppos)
222 {
223 char buf[16];
224 int mode;
225
226 if (cnt > 15)
227 cnt = 15;
228
229 if (copy_from_user(&buf, ubuf, cnt))
230 return -EFAULT;
231
232 buf[cnt] = 0;
233 mode = sched_dynamic_mode(strstrip(buf));
234 if (mode < 0)
235 return mode;
236
237 sched_dynamic_update(mode);
238
239 *ppos += cnt;
240
241 return cnt;
242 }
243
sched_dynamic_show(struct seq_file * m,void * v)244 static int sched_dynamic_show(struct seq_file *m, void *v)
245 {
246 int i = IS_ENABLED(CONFIG_PREEMPT_RT) * 2;
247 int j;
248
249 /* Count entries in NULL terminated preempt_modes */
250 for (j = 0; preempt_modes[j]; j++)
251 ;
252 j -= !IS_ENABLED(CONFIG_ARCH_HAS_PREEMPT_LAZY);
253
254 for (; i < j; i++) {
255 if (preempt_dynamic_mode == i)
256 seq_puts(m, "(");
257 seq_puts(m, preempt_modes[i]);
258 if (preempt_dynamic_mode == i)
259 seq_puts(m, ")");
260
261 seq_puts(m, " ");
262 }
263
264 seq_puts(m, "\n");
265 return 0;
266 }
267
sched_dynamic_open(struct inode * inode,struct file * filp)268 static int sched_dynamic_open(struct inode *inode, struct file *filp)
269 {
270 return single_open(filp, sched_dynamic_show, NULL);
271 }
272
273 static const struct file_operations sched_dynamic_fops = {
274 .open = sched_dynamic_open,
275 .write = sched_dynamic_write,
276 .read = seq_read,
277 .llseek = seq_lseek,
278 .release = single_release,
279 };
280
281 #endif /* CONFIG_PREEMPT_DYNAMIC */
282
283 __read_mostly bool sched_debug_verbose;
284
285 static struct dentry *sd_dentry;
286
287
sched_verbose_write(struct file * filp,const char __user * ubuf,size_t cnt,loff_t * ppos)288 static ssize_t sched_verbose_write(struct file *filp, const char __user *ubuf,
289 size_t cnt, loff_t *ppos)
290 {
291 ssize_t result;
292 bool orig;
293
294 cpus_read_lock();
295 sched_domains_mutex_lock();
296
297 orig = sched_debug_verbose;
298 result = debugfs_write_file_bool(filp, ubuf, cnt, ppos);
299
300 if (sched_debug_verbose && !orig)
301 update_sched_domain_debugfs();
302 else if (!sched_debug_verbose && orig) {
303 debugfs_remove(sd_dentry);
304 sd_dentry = NULL;
305 }
306
307 sched_domains_mutex_unlock();
308 cpus_read_unlock();
309
310 return result;
311 }
312
313 static const struct file_operations sched_verbose_fops = {
314 .read = debugfs_read_file_bool,
315 .write = sched_verbose_write,
316 .open = simple_open,
317 .llseek = default_llseek,
318 };
319
320 static const struct seq_operations sched_debug_sops;
321
sched_debug_open(struct inode * inode,struct file * filp)322 static int sched_debug_open(struct inode *inode, struct file *filp)
323 {
324 return seq_open(filp, &sched_debug_sops);
325 }
326
327 static const struct file_operations sched_debug_fops = {
328 .open = sched_debug_open,
329 .read = seq_read,
330 .llseek = seq_lseek,
331 .release = seq_release,
332 };
333
334 enum dl_param {
335 DL_RUNTIME = 0,
336 DL_PERIOD,
337 };
338
339 static unsigned long fair_server_period_max = (1UL << 22) * NSEC_PER_USEC; /* ~4 seconds */
340 static unsigned long fair_server_period_min = (100) * NSEC_PER_USEC; /* 100 us */
341
sched_fair_server_write(struct file * filp,const char __user * ubuf,size_t cnt,loff_t * ppos,enum dl_param param)342 static ssize_t sched_fair_server_write(struct file *filp, const char __user *ubuf,
343 size_t cnt, loff_t *ppos, enum dl_param param)
344 {
345 long cpu = (long) ((struct seq_file *) filp->private_data)->private;
346 struct rq *rq = cpu_rq(cpu);
347 u64 runtime, period;
348 size_t err;
349 int retval;
350 u64 value;
351
352 err = kstrtoull_from_user(ubuf, cnt, 10, &value);
353 if (err)
354 return err;
355
356 scoped_guard (rq_lock_irqsave, rq) {
357 runtime = rq->fair_server.dl_runtime;
358 period = rq->fair_server.dl_period;
359
360 switch (param) {
361 case DL_RUNTIME:
362 if (runtime == value)
363 break;
364 runtime = value;
365 break;
366 case DL_PERIOD:
367 if (value == period)
368 break;
369 period = value;
370 break;
371 }
372
373 if (runtime > period ||
374 period > fair_server_period_max ||
375 period < fair_server_period_min) {
376 return -EINVAL;
377 }
378
379 if (rq->cfs.h_nr_queued) {
380 update_rq_clock(rq);
381 dl_server_stop(&rq->fair_server);
382 }
383
384 retval = dl_server_apply_params(&rq->fair_server, runtime, period, 0);
385 if (retval)
386 cnt = retval;
387
388 if (!runtime)
389 printk_deferred("Fair server disabled in CPU %d, system may crash due to starvation.\n",
390 cpu_of(rq));
391
392 if (rq->cfs.h_nr_queued)
393 dl_server_start(&rq->fair_server);
394 }
395
396 *ppos += cnt;
397 return cnt;
398 }
399
sched_fair_server_show(struct seq_file * m,void * v,enum dl_param param)400 static size_t sched_fair_server_show(struct seq_file *m, void *v, enum dl_param param)
401 {
402 unsigned long cpu = (unsigned long) m->private;
403 struct rq *rq = cpu_rq(cpu);
404 u64 value;
405
406 switch (param) {
407 case DL_RUNTIME:
408 value = rq->fair_server.dl_runtime;
409 break;
410 case DL_PERIOD:
411 value = rq->fair_server.dl_period;
412 break;
413 }
414
415 seq_printf(m, "%llu\n", value);
416 return 0;
417
418 }
419
420 static ssize_t
sched_fair_server_runtime_write(struct file * filp,const char __user * ubuf,size_t cnt,loff_t * ppos)421 sched_fair_server_runtime_write(struct file *filp, const char __user *ubuf,
422 size_t cnt, loff_t *ppos)
423 {
424 return sched_fair_server_write(filp, ubuf, cnt, ppos, DL_RUNTIME);
425 }
426
sched_fair_server_runtime_show(struct seq_file * m,void * v)427 static int sched_fair_server_runtime_show(struct seq_file *m, void *v)
428 {
429 return sched_fair_server_show(m, v, DL_RUNTIME);
430 }
431
sched_fair_server_runtime_open(struct inode * inode,struct file * filp)432 static int sched_fair_server_runtime_open(struct inode *inode, struct file *filp)
433 {
434 return single_open(filp, sched_fair_server_runtime_show, inode->i_private);
435 }
436
437 static const struct file_operations fair_server_runtime_fops = {
438 .open = sched_fair_server_runtime_open,
439 .write = sched_fair_server_runtime_write,
440 .read = seq_read,
441 .llseek = seq_lseek,
442 .release = single_release,
443 };
444
445 static ssize_t
sched_fair_server_period_write(struct file * filp,const char __user * ubuf,size_t cnt,loff_t * ppos)446 sched_fair_server_period_write(struct file *filp, const char __user *ubuf,
447 size_t cnt, loff_t *ppos)
448 {
449 return sched_fair_server_write(filp, ubuf, cnt, ppos, DL_PERIOD);
450 }
451
sched_fair_server_period_show(struct seq_file * m,void * v)452 static int sched_fair_server_period_show(struct seq_file *m, void *v)
453 {
454 return sched_fair_server_show(m, v, DL_PERIOD);
455 }
456
sched_fair_server_period_open(struct inode * inode,struct file * filp)457 static int sched_fair_server_period_open(struct inode *inode, struct file *filp)
458 {
459 return single_open(filp, sched_fair_server_period_show, inode->i_private);
460 }
461
462 static const struct file_operations fair_server_period_fops = {
463 .open = sched_fair_server_period_open,
464 .write = sched_fair_server_period_write,
465 .read = seq_read,
466 .llseek = seq_lseek,
467 .release = single_release,
468 };
469
470 static struct dentry *debugfs_sched;
471
debugfs_fair_server_init(void)472 static void debugfs_fair_server_init(void)
473 {
474 struct dentry *d_fair;
475 unsigned long cpu;
476
477 d_fair = debugfs_create_dir("fair_server", debugfs_sched);
478 if (!d_fair)
479 return;
480
481 for_each_possible_cpu(cpu) {
482 struct dentry *d_cpu;
483 char buf[32];
484
485 snprintf(buf, sizeof(buf), "cpu%lu", cpu);
486 d_cpu = debugfs_create_dir(buf, d_fair);
487
488 debugfs_create_file("runtime", 0644, d_cpu, (void *) cpu, &fair_server_runtime_fops);
489 debugfs_create_file("period", 0644, d_cpu, (void *) cpu, &fair_server_period_fops);
490 }
491 }
492
sched_init_debug(void)493 static __init int sched_init_debug(void)
494 {
495 struct dentry __maybe_unused *numa;
496
497 debugfs_sched = debugfs_create_dir("sched", NULL);
498
499 debugfs_create_file("features", 0644, debugfs_sched, NULL, &sched_feat_fops);
500 debugfs_create_file_unsafe("verbose", 0644, debugfs_sched, &sched_debug_verbose, &sched_verbose_fops);
501 #ifdef CONFIG_PREEMPT_DYNAMIC
502 debugfs_create_file("preempt", 0644, debugfs_sched, NULL, &sched_dynamic_fops);
503 #endif
504
505 debugfs_create_u32("base_slice_ns", 0644, debugfs_sched, &sysctl_sched_base_slice);
506
507 debugfs_create_u32("latency_warn_ms", 0644, debugfs_sched, &sysctl_resched_latency_warn_ms);
508 debugfs_create_u32("latency_warn_once", 0644, debugfs_sched, &sysctl_resched_latency_warn_once);
509
510 debugfs_create_file("tunable_scaling", 0644, debugfs_sched, NULL, &sched_scaling_fops);
511 debugfs_create_u32("migration_cost_ns", 0644, debugfs_sched, &sysctl_sched_migration_cost);
512 debugfs_create_u32("nr_migrate", 0644, debugfs_sched, &sysctl_sched_nr_migrate);
513
514 sched_domains_mutex_lock();
515 update_sched_domain_debugfs();
516 sched_domains_mutex_unlock();
517
518 #ifdef CONFIG_NUMA_BALANCING
519 numa = debugfs_create_dir("numa_balancing", debugfs_sched);
520
521 debugfs_create_u32("scan_delay_ms", 0644, numa, &sysctl_numa_balancing_scan_delay);
522 debugfs_create_u32("scan_period_min_ms", 0644, numa, &sysctl_numa_balancing_scan_period_min);
523 debugfs_create_u32("scan_period_max_ms", 0644, numa, &sysctl_numa_balancing_scan_period_max);
524 debugfs_create_u32("scan_size_mb", 0644, numa, &sysctl_numa_balancing_scan_size);
525 debugfs_create_u32("hot_threshold_ms", 0644, numa, &sysctl_numa_balancing_hot_threshold);
526 #endif /* CONFIG_NUMA_BALANCING */
527
528 debugfs_create_file("debug", 0444, debugfs_sched, NULL, &sched_debug_fops);
529
530 debugfs_fair_server_init();
531
532 return 0;
533 }
534 late_initcall(sched_init_debug);
535
536 static cpumask_var_t sd_sysctl_cpus;
537
sd_flags_show(struct seq_file * m,void * v)538 static int sd_flags_show(struct seq_file *m, void *v)
539 {
540 unsigned long flags = *(unsigned int *)m->private;
541 int idx;
542
543 for_each_set_bit(idx, &flags, __SD_FLAG_CNT) {
544 seq_puts(m, sd_flag_debug[idx].name);
545 seq_puts(m, " ");
546 }
547 seq_puts(m, "\n");
548
549 return 0;
550 }
551
sd_flags_open(struct inode * inode,struct file * file)552 static int sd_flags_open(struct inode *inode, struct file *file)
553 {
554 return single_open(file, sd_flags_show, inode->i_private);
555 }
556
557 static const struct file_operations sd_flags_fops = {
558 .open = sd_flags_open,
559 .read = seq_read,
560 .llseek = seq_lseek,
561 .release = single_release,
562 };
563
register_sd(struct sched_domain * sd,struct dentry * parent)564 static void register_sd(struct sched_domain *sd, struct dentry *parent)
565 {
566 #define SDM(type, mode, member) \
567 debugfs_create_##type(#member, mode, parent, &sd->member)
568
569 SDM(ulong, 0644, min_interval);
570 SDM(ulong, 0644, max_interval);
571 SDM(u64, 0644, max_newidle_lb_cost);
572 SDM(u32, 0644, busy_factor);
573 SDM(u32, 0644, imbalance_pct);
574 SDM(u32, 0644, cache_nice_tries);
575 SDM(str, 0444, name);
576
577 #undef SDM
578
579 debugfs_create_file("flags", 0444, parent, &sd->flags, &sd_flags_fops);
580 debugfs_create_file("groups_flags", 0444, parent, &sd->groups->flags, &sd_flags_fops);
581 debugfs_create_u32("level", 0444, parent, (u32 *)&sd->level);
582
583 if (sd->flags & SD_ASYM_PACKING)
584 debugfs_create_u32("group_asym_prefer_cpu", 0444, parent,
585 (u32 *)&sd->groups->asym_prefer_cpu);
586 }
587
update_sched_domain_debugfs(void)588 void update_sched_domain_debugfs(void)
589 {
590 int cpu, i;
591
592 /*
593 * This can unfortunately be invoked before sched_debug_init() creates
594 * the debug directory. Don't touch sd_sysctl_cpus until then.
595 */
596 if (!debugfs_sched)
597 return;
598
599 if (!sched_debug_verbose)
600 return;
601
602 if (!cpumask_available(sd_sysctl_cpus)) {
603 if (!alloc_cpumask_var(&sd_sysctl_cpus, GFP_KERNEL))
604 return;
605 cpumask_copy(sd_sysctl_cpus, cpu_possible_mask);
606 }
607
608 if (!sd_dentry) {
609 sd_dentry = debugfs_create_dir("domains", debugfs_sched);
610
611 /* rebuild sd_sysctl_cpus if empty since it gets cleared below */
612 if (cpumask_empty(sd_sysctl_cpus))
613 cpumask_copy(sd_sysctl_cpus, cpu_online_mask);
614 }
615
616 for_each_cpu(cpu, sd_sysctl_cpus) {
617 struct sched_domain *sd;
618 struct dentry *d_cpu;
619 char buf[32];
620
621 snprintf(buf, sizeof(buf), "cpu%d", cpu);
622 debugfs_lookup_and_remove(buf, sd_dentry);
623 d_cpu = debugfs_create_dir(buf, sd_dentry);
624
625 i = 0;
626 for_each_domain(cpu, sd) {
627 struct dentry *d_sd;
628
629 snprintf(buf, sizeof(buf), "domain%d", i);
630 d_sd = debugfs_create_dir(buf, d_cpu);
631
632 register_sd(sd, d_sd);
633 i++;
634 }
635
636 __cpumask_clear_cpu(cpu, sd_sysctl_cpus);
637 }
638 }
639
dirty_sched_domain_sysctl(int cpu)640 void dirty_sched_domain_sysctl(int cpu)
641 {
642 if (cpumask_available(sd_sysctl_cpus))
643 __cpumask_set_cpu(cpu, sd_sysctl_cpus);
644 }
645
646 #ifdef CONFIG_FAIR_GROUP_SCHED
print_cfs_group_stats(struct seq_file * m,int cpu,struct task_group * tg)647 static void print_cfs_group_stats(struct seq_file *m, int cpu, struct task_group *tg)
648 {
649 struct sched_entity *se = tg->se[cpu];
650
651 #define P(F) SEQ_printf(m, " .%-30s: %lld\n", #F, (long long)F)
652 #define P_SCHEDSTAT(F) SEQ_printf(m, " .%-30s: %lld\n", \
653 #F, (long long)schedstat_val(stats->F))
654 #define PN(F) SEQ_printf(m, " .%-30s: %lld.%06ld\n", #F, SPLIT_NS((long long)F))
655 #define PN_SCHEDSTAT(F) SEQ_printf(m, " .%-30s: %lld.%06ld\n", \
656 #F, SPLIT_NS((long long)schedstat_val(stats->F)))
657
658 if (!se)
659 return;
660
661 PN(se->exec_start);
662 PN(se->vruntime);
663 PN(se->sum_exec_runtime);
664
665 if (schedstat_enabled()) {
666 struct sched_statistics *stats;
667 stats = __schedstats_from_se(se);
668
669 PN_SCHEDSTAT(wait_start);
670 PN_SCHEDSTAT(sleep_start);
671 PN_SCHEDSTAT(block_start);
672 PN_SCHEDSTAT(sleep_max);
673 PN_SCHEDSTAT(block_max);
674 PN_SCHEDSTAT(exec_max);
675 PN_SCHEDSTAT(slice_max);
676 PN_SCHEDSTAT(wait_max);
677 PN_SCHEDSTAT(wait_sum);
678 P_SCHEDSTAT(wait_count);
679 }
680
681 P(se->load.weight);
682 P(se->avg.load_avg);
683 P(se->avg.util_avg);
684 P(se->avg.runnable_avg);
685
686 #undef PN_SCHEDSTAT
687 #undef PN
688 #undef P_SCHEDSTAT
689 #undef P
690 }
691 #endif /* CONFIG_FAIR_GROUP_SCHED */
692
693 #ifdef CONFIG_CGROUP_SCHED
694 static DEFINE_SPINLOCK(sched_debug_lock);
695 static char group_path[PATH_MAX];
696
task_group_path(struct task_group * tg,char * path,int plen)697 static void task_group_path(struct task_group *tg, char *path, int plen)
698 {
699 if (autogroup_path(tg, path, plen))
700 return;
701
702 cgroup_path(tg->css.cgroup, path, plen);
703 }
704
705 /*
706 * Only 1 SEQ_printf_task_group_path() caller can use the full length
707 * group_path[] for cgroup path. Other simultaneous callers will have
708 * to use a shorter stack buffer. A "..." suffix is appended at the end
709 * of the stack buffer so that it will show up in case the output length
710 * matches the given buffer size to indicate possible path name truncation.
711 */
712 #define SEQ_printf_task_group_path(m, tg, fmt...) \
713 { \
714 if (spin_trylock(&sched_debug_lock)) { \
715 task_group_path(tg, group_path, sizeof(group_path)); \
716 SEQ_printf(m, fmt, group_path); \
717 spin_unlock(&sched_debug_lock); \
718 } else { \
719 char buf[128]; \
720 char *bufend = buf + sizeof(buf) - 3; \
721 task_group_path(tg, buf, bufend - buf); \
722 strcpy(bufend - 1, "..."); \
723 SEQ_printf(m, fmt, buf); \
724 } \
725 }
726 #endif
727
728 static void
print_task(struct seq_file * m,struct rq * rq,struct task_struct * p)729 print_task(struct seq_file *m, struct rq *rq, struct task_struct *p)
730 {
731 if (task_current(rq, p))
732 SEQ_printf(m, ">R");
733 else
734 SEQ_printf(m, " %c", task_state_to_char(p));
735
736 SEQ_printf(m, " %15s %5d %9Ld.%06ld %c %9Ld.%06ld %c %9Ld.%06ld %9Ld.%06ld %9Ld %5d ",
737 p->comm, task_pid_nr(p),
738 SPLIT_NS(p->se.vruntime),
739 entity_eligible(cfs_rq_of(&p->se), &p->se) ? 'E' : 'N',
740 SPLIT_NS(p->se.deadline),
741 p->se.custom_slice ? 'S' : ' ',
742 SPLIT_NS(p->se.slice),
743 SPLIT_NS(p->se.sum_exec_runtime),
744 (long long)(p->nvcsw + p->nivcsw),
745 p->prio);
746
747 SEQ_printf(m, "%9lld.%06ld %9lld.%06ld %9lld.%06ld",
748 SPLIT_NS(schedstat_val_or_zero(p->stats.wait_sum)),
749 SPLIT_NS(schedstat_val_or_zero(p->stats.sum_sleep_runtime)),
750 SPLIT_NS(schedstat_val_or_zero(p->stats.sum_block_runtime)));
751
752 #ifdef CONFIG_NUMA_BALANCING
753 SEQ_printf(m, " %d %d", task_node(p), task_numa_group_id(p));
754 #endif
755 #ifdef CONFIG_CGROUP_SCHED
756 SEQ_printf_task_group_path(m, task_group(p), " %s")
757 #endif
758
759 SEQ_printf(m, "\n");
760 }
761
print_rq(struct seq_file * m,struct rq * rq,int rq_cpu)762 static void print_rq(struct seq_file *m, struct rq *rq, int rq_cpu)
763 {
764 struct task_struct *g, *p;
765
766 SEQ_printf(m, "\n");
767 SEQ_printf(m, "runnable tasks:\n");
768 SEQ_printf(m, " S task PID vruntime eligible "
769 "deadline slice sum-exec switches "
770 "prio wait-time sum-sleep sum-block"
771 #ifdef CONFIG_NUMA_BALANCING
772 " node group-id"
773 #endif
774 #ifdef CONFIG_CGROUP_SCHED
775 " group-path"
776 #endif
777 "\n");
778 SEQ_printf(m, "-------------------------------------------------------"
779 "------------------------------------------------------"
780 "------------------------------------------------------"
781 #ifdef CONFIG_NUMA_BALANCING
782 "--------------"
783 #endif
784 #ifdef CONFIG_CGROUP_SCHED
785 "--------------"
786 #endif
787 "\n");
788
789 rcu_read_lock();
790 for_each_process_thread(g, p) {
791 if (task_cpu(p) != rq_cpu)
792 continue;
793
794 print_task(m, rq, p);
795 }
796 rcu_read_unlock();
797 }
798
print_cfs_rq(struct seq_file * m,int cpu,struct cfs_rq * cfs_rq)799 void print_cfs_rq(struct seq_file *m, int cpu, struct cfs_rq *cfs_rq)
800 {
801 s64 left_vruntime = -1, min_vruntime, right_vruntime = -1, left_deadline = -1, spread;
802 struct sched_entity *last, *first, *root;
803 struct rq *rq = cpu_rq(cpu);
804 unsigned long flags;
805
806 #ifdef CONFIG_FAIR_GROUP_SCHED
807 SEQ_printf(m, "\n");
808 SEQ_printf_task_group_path(m, cfs_rq->tg, "cfs_rq[%d]:%s\n", cpu);
809 #else
810 SEQ_printf(m, "\n");
811 SEQ_printf(m, "cfs_rq[%d]:\n", cpu);
812 #endif
813
814 raw_spin_rq_lock_irqsave(rq, flags);
815 root = __pick_root_entity(cfs_rq);
816 if (root)
817 left_vruntime = root->min_vruntime;
818 first = __pick_first_entity(cfs_rq);
819 if (first)
820 left_deadline = first->deadline;
821 last = __pick_last_entity(cfs_rq);
822 if (last)
823 right_vruntime = last->vruntime;
824 min_vruntime = cfs_rq->min_vruntime;
825 raw_spin_rq_unlock_irqrestore(rq, flags);
826
827 SEQ_printf(m, " .%-30s: %Ld.%06ld\n", "left_deadline",
828 SPLIT_NS(left_deadline));
829 SEQ_printf(m, " .%-30s: %Ld.%06ld\n", "left_vruntime",
830 SPLIT_NS(left_vruntime));
831 SEQ_printf(m, " .%-30s: %Ld.%06ld\n", "min_vruntime",
832 SPLIT_NS(min_vruntime));
833 SEQ_printf(m, " .%-30s: %Ld.%06ld\n", "avg_vruntime",
834 SPLIT_NS(avg_vruntime(cfs_rq)));
835 SEQ_printf(m, " .%-30s: %Ld.%06ld\n", "right_vruntime",
836 SPLIT_NS(right_vruntime));
837 spread = right_vruntime - left_vruntime;
838 SEQ_printf(m, " .%-30s: %Ld.%06ld\n", "spread", SPLIT_NS(spread));
839 SEQ_printf(m, " .%-30s: %d\n", "nr_queued", cfs_rq->nr_queued);
840 SEQ_printf(m, " .%-30s: %d\n", "h_nr_runnable", cfs_rq->h_nr_runnable);
841 SEQ_printf(m, " .%-30s: %d\n", "h_nr_queued", cfs_rq->h_nr_queued);
842 SEQ_printf(m, " .%-30s: %d\n", "h_nr_idle", cfs_rq->h_nr_idle);
843 SEQ_printf(m, " .%-30s: %ld\n", "load", cfs_rq->load.weight);
844 SEQ_printf(m, " .%-30s: %lu\n", "load_avg",
845 cfs_rq->avg.load_avg);
846 SEQ_printf(m, " .%-30s: %lu\n", "runnable_avg",
847 cfs_rq->avg.runnable_avg);
848 SEQ_printf(m, " .%-30s: %lu\n", "util_avg",
849 cfs_rq->avg.util_avg);
850 SEQ_printf(m, " .%-30s: %u\n", "util_est",
851 cfs_rq->avg.util_est);
852 SEQ_printf(m, " .%-30s: %ld\n", "removed.load_avg",
853 cfs_rq->removed.load_avg);
854 SEQ_printf(m, " .%-30s: %ld\n", "removed.util_avg",
855 cfs_rq->removed.util_avg);
856 SEQ_printf(m, " .%-30s: %ld\n", "removed.runnable_avg",
857 cfs_rq->removed.runnable_avg);
858 #ifdef CONFIG_FAIR_GROUP_SCHED
859 SEQ_printf(m, " .%-30s: %lu\n", "tg_load_avg_contrib",
860 cfs_rq->tg_load_avg_contrib);
861 SEQ_printf(m, " .%-30s: %ld\n", "tg_load_avg",
862 atomic_long_read(&cfs_rq->tg->load_avg));
863 #endif /* CONFIG_FAIR_GROUP_SCHED */
864 #ifdef CONFIG_CFS_BANDWIDTH
865 SEQ_printf(m, " .%-30s: %d\n", "throttled",
866 cfs_rq->throttled);
867 SEQ_printf(m, " .%-30s: %d\n", "throttle_count",
868 cfs_rq->throttle_count);
869 #endif
870
871 #ifdef CONFIG_FAIR_GROUP_SCHED
872 print_cfs_group_stats(m, cpu, cfs_rq->tg);
873 #endif
874 }
875
print_rt_rq(struct seq_file * m,int cpu,struct rt_rq * rt_rq)876 void print_rt_rq(struct seq_file *m, int cpu, struct rt_rq *rt_rq)
877 {
878 #ifdef CONFIG_RT_GROUP_SCHED
879 SEQ_printf(m, "\n");
880 SEQ_printf_task_group_path(m, rt_rq->tg, "rt_rq[%d]:%s\n", cpu);
881 #else
882 SEQ_printf(m, "\n");
883 SEQ_printf(m, "rt_rq[%d]:\n", cpu);
884 #endif
885
886 #define P(x) \
887 SEQ_printf(m, " .%-30s: %Ld\n", #x, (long long)(rt_rq->x))
888 #define PU(x) \
889 SEQ_printf(m, " .%-30s: %lu\n", #x, (unsigned long)(rt_rq->x))
890 #define PN(x) \
891 SEQ_printf(m, " .%-30s: %Ld.%06ld\n", #x, SPLIT_NS(rt_rq->x))
892
893 PU(rt_nr_running);
894
895 #ifdef CONFIG_RT_GROUP_SCHED
896 P(rt_throttled);
897 PN(rt_time);
898 PN(rt_runtime);
899 #endif
900
901 #undef PN
902 #undef PU
903 #undef P
904 }
905
print_dl_rq(struct seq_file * m,int cpu,struct dl_rq * dl_rq)906 void print_dl_rq(struct seq_file *m, int cpu, struct dl_rq *dl_rq)
907 {
908 struct dl_bw *dl_bw;
909
910 SEQ_printf(m, "\n");
911 SEQ_printf(m, "dl_rq[%d]:\n", cpu);
912
913 #define PU(x) \
914 SEQ_printf(m, " .%-30s: %lu\n", #x, (unsigned long)(dl_rq->x))
915
916 PU(dl_nr_running);
917 dl_bw = &cpu_rq(cpu)->rd->dl_bw;
918 SEQ_printf(m, " .%-30s: %lld\n", "dl_bw->bw", dl_bw->bw);
919 SEQ_printf(m, " .%-30s: %lld\n", "dl_bw->total_bw", dl_bw->total_bw);
920
921 #undef PU
922 }
923
print_cpu(struct seq_file * m,int cpu)924 static void print_cpu(struct seq_file *m, int cpu)
925 {
926 struct rq *rq = cpu_rq(cpu);
927
928 #ifdef CONFIG_X86
929 {
930 unsigned int freq = cpu_khz ? : 1;
931
932 SEQ_printf(m, "cpu#%d, %u.%03u MHz\n",
933 cpu, freq / 1000, (freq % 1000));
934 }
935 #else /* !CONFIG_X86: */
936 SEQ_printf(m, "cpu#%d\n", cpu);
937 #endif /* !CONFIG_X86 */
938
939 #define P(x) \
940 do { \
941 if (sizeof(rq->x) == 4) \
942 SEQ_printf(m, " .%-30s: %d\n", #x, (int)(rq->x)); \
943 else \
944 SEQ_printf(m, " .%-30s: %Ld\n", #x, (long long)(rq->x));\
945 } while (0)
946
947 #define PN(x) \
948 SEQ_printf(m, " .%-30s: %Ld.%06ld\n", #x, SPLIT_NS(rq->x))
949
950 P(nr_running);
951 P(nr_switches);
952 P(nr_uninterruptible);
953 PN(next_balance);
954 SEQ_printf(m, " .%-30s: %ld\n", "curr->pid", (long)(task_pid_nr(rq->curr)));
955 PN(clock);
956 PN(clock_task);
957 #undef P
958 #undef PN
959
960 #define P64(n) SEQ_printf(m, " .%-30s: %Ld\n", #n, rq->n);
961 P64(avg_idle);
962 P64(max_idle_balance_cost);
963 #undef P64
964
965 #define P(n) SEQ_printf(m, " .%-30s: %d\n", #n, schedstat_val(rq->n));
966 if (schedstat_enabled()) {
967 P(yld_count);
968 P(sched_count);
969 P(sched_goidle);
970 P(ttwu_count);
971 P(ttwu_local);
972 }
973 #undef P
974
975 print_cfs_stats(m, cpu);
976 print_rt_stats(m, cpu);
977 print_dl_stats(m, cpu);
978
979 print_rq(m, rq, cpu);
980 SEQ_printf(m, "\n");
981 }
982
983 static const char *sched_tunable_scaling_names[] = {
984 "none",
985 "logarithmic",
986 "linear"
987 };
988
sched_debug_header(struct seq_file * m)989 static void sched_debug_header(struct seq_file *m)
990 {
991 u64 ktime, sched_clk, cpu_clk;
992 unsigned long flags;
993
994 local_irq_save(flags);
995 ktime = ktime_to_ns(ktime_get());
996 sched_clk = sched_clock();
997 cpu_clk = local_clock();
998 local_irq_restore(flags);
999
1000 SEQ_printf(m, "Sched Debug Version: v0.11, %s %.*s\n",
1001 init_utsname()->release,
1002 (int)strcspn(init_utsname()->version, " "),
1003 init_utsname()->version);
1004
1005 #define P(x) \
1006 SEQ_printf(m, "%-40s: %Ld\n", #x, (long long)(x))
1007 #define PN(x) \
1008 SEQ_printf(m, "%-40s: %Ld.%06ld\n", #x, SPLIT_NS(x))
1009 PN(ktime);
1010 PN(sched_clk);
1011 PN(cpu_clk);
1012 P(jiffies);
1013 #ifdef CONFIG_HAVE_UNSTABLE_SCHED_CLOCK
1014 P(sched_clock_stable());
1015 #endif
1016 #undef PN
1017 #undef P
1018
1019 SEQ_printf(m, "\n");
1020 SEQ_printf(m, "sysctl_sched\n");
1021
1022 #define P(x) \
1023 SEQ_printf(m, " .%-40s: %Ld\n", #x, (long long)(x))
1024 #define PN(x) \
1025 SEQ_printf(m, " .%-40s: %Ld.%06ld\n", #x, SPLIT_NS(x))
1026 PN(sysctl_sched_base_slice);
1027 P(sysctl_sched_features);
1028 #undef PN
1029 #undef P
1030
1031 SEQ_printf(m, " .%-40s: %d (%s)\n",
1032 "sysctl_sched_tunable_scaling",
1033 sysctl_sched_tunable_scaling,
1034 sched_tunable_scaling_names[sysctl_sched_tunable_scaling]);
1035 SEQ_printf(m, "\n");
1036 }
1037
sched_debug_show(struct seq_file * m,void * v)1038 static int sched_debug_show(struct seq_file *m, void *v)
1039 {
1040 int cpu = (unsigned long)(v - 2);
1041
1042 if (cpu != -1)
1043 print_cpu(m, cpu);
1044 else
1045 sched_debug_header(m);
1046
1047 return 0;
1048 }
1049
sysrq_sched_debug_show(void)1050 void sysrq_sched_debug_show(void)
1051 {
1052 int cpu;
1053
1054 sched_debug_header(NULL);
1055 for_each_online_cpu(cpu) {
1056 /*
1057 * Need to reset softlockup watchdogs on all CPUs, because
1058 * another CPU might be blocked waiting for us to process
1059 * an IPI or stop_machine.
1060 */
1061 touch_nmi_watchdog();
1062 touch_all_softlockup_watchdogs();
1063 print_cpu(NULL, cpu);
1064 }
1065 }
1066
1067 /*
1068 * This iterator needs some explanation.
1069 * It returns 1 for the header position.
1070 * This means 2 is CPU 0.
1071 * In a hotplugged system some CPUs, including CPU 0, may be missing so we have
1072 * to use cpumask_* to iterate over the CPUs.
1073 */
sched_debug_start(struct seq_file * file,loff_t * offset)1074 static void *sched_debug_start(struct seq_file *file, loff_t *offset)
1075 {
1076 unsigned long n = *offset;
1077
1078 if (n == 0)
1079 return (void *) 1;
1080
1081 n--;
1082
1083 if (n > 0)
1084 n = cpumask_next(n - 1, cpu_online_mask);
1085 else
1086 n = cpumask_first(cpu_online_mask);
1087
1088 *offset = n + 1;
1089
1090 if (n < nr_cpu_ids)
1091 return (void *)(unsigned long)(n + 2);
1092
1093 return NULL;
1094 }
1095
sched_debug_next(struct seq_file * file,void * data,loff_t * offset)1096 static void *sched_debug_next(struct seq_file *file, void *data, loff_t *offset)
1097 {
1098 (*offset)++;
1099 return sched_debug_start(file, offset);
1100 }
1101
sched_debug_stop(struct seq_file * file,void * data)1102 static void sched_debug_stop(struct seq_file *file, void *data)
1103 {
1104 }
1105
1106 static const struct seq_operations sched_debug_sops = {
1107 .start = sched_debug_start,
1108 .next = sched_debug_next,
1109 .stop = sched_debug_stop,
1110 .show = sched_debug_show,
1111 };
1112
1113 #define __PS(S, F) SEQ_printf(m, "%-45s:%21Ld\n", S, (long long)(F))
1114 #define __P(F) __PS(#F, F)
1115 #define P(F) __PS(#F, p->F)
1116 #define PM(F, M) __PS(#F, p->F & (M))
1117 #define __PSN(S, F) SEQ_printf(m, "%-45s:%14Ld.%06ld\n", S, SPLIT_NS((long long)(F)))
1118 #define __PN(F) __PSN(#F, F)
1119 #define PN(F) __PSN(#F, p->F)
1120
1121
1122 #ifdef CONFIG_NUMA_BALANCING
print_numa_stats(struct seq_file * m,int node,unsigned long tsf,unsigned long tpf,unsigned long gsf,unsigned long gpf)1123 void print_numa_stats(struct seq_file *m, int node, unsigned long tsf,
1124 unsigned long tpf, unsigned long gsf, unsigned long gpf)
1125 {
1126 SEQ_printf(m, "numa_faults node=%d ", node);
1127 SEQ_printf(m, "task_private=%lu task_shared=%lu ", tpf, tsf);
1128 SEQ_printf(m, "group_private=%lu group_shared=%lu\n", gpf, gsf);
1129 }
1130 #endif
1131
1132
sched_show_numa(struct task_struct * p,struct seq_file * m)1133 static void sched_show_numa(struct task_struct *p, struct seq_file *m)
1134 {
1135 #ifdef CONFIG_NUMA_BALANCING
1136 if (p->mm)
1137 P(mm->numa_scan_seq);
1138
1139 P(numa_pages_migrated);
1140 P(numa_preferred_nid);
1141 P(total_numa_faults);
1142 SEQ_printf(m, "current_node=%d, numa_group_id=%d\n",
1143 task_node(p), task_numa_group_id(p));
1144 show_numa_stats(p, m);
1145 #endif /* CONFIG_NUMA_BALANCING */
1146 }
1147
proc_sched_show_task(struct task_struct * p,struct pid_namespace * ns,struct seq_file * m)1148 void proc_sched_show_task(struct task_struct *p, struct pid_namespace *ns,
1149 struct seq_file *m)
1150 {
1151 unsigned long nr_switches;
1152
1153 SEQ_printf(m, "%s (%d, #threads: %d)\n", p->comm, task_pid_nr_ns(p, ns),
1154 get_nr_threads(p));
1155 SEQ_printf(m,
1156 "---------------------------------------------------------"
1157 "----------\n");
1158
1159 #define P_SCHEDSTAT(F) __PS(#F, schedstat_val(p->stats.F))
1160 #define PN_SCHEDSTAT(F) __PSN(#F, schedstat_val(p->stats.F))
1161
1162 PN(se.exec_start);
1163 PN(se.vruntime);
1164 PN(se.sum_exec_runtime);
1165
1166 nr_switches = p->nvcsw + p->nivcsw;
1167
1168 P(se.nr_migrations);
1169
1170 if (schedstat_enabled()) {
1171 u64 avg_atom, avg_per_cpu;
1172
1173 PN_SCHEDSTAT(sum_sleep_runtime);
1174 PN_SCHEDSTAT(sum_block_runtime);
1175 PN_SCHEDSTAT(wait_start);
1176 PN_SCHEDSTAT(sleep_start);
1177 PN_SCHEDSTAT(block_start);
1178 PN_SCHEDSTAT(sleep_max);
1179 PN_SCHEDSTAT(block_max);
1180 PN_SCHEDSTAT(exec_max);
1181 PN_SCHEDSTAT(slice_max);
1182 PN_SCHEDSTAT(wait_max);
1183 PN_SCHEDSTAT(wait_sum);
1184 P_SCHEDSTAT(wait_count);
1185 PN_SCHEDSTAT(iowait_sum);
1186 P_SCHEDSTAT(iowait_count);
1187 P_SCHEDSTAT(nr_migrations_cold);
1188 P_SCHEDSTAT(nr_failed_migrations_affine);
1189 P_SCHEDSTAT(nr_failed_migrations_running);
1190 P_SCHEDSTAT(nr_failed_migrations_hot);
1191 P_SCHEDSTAT(nr_forced_migrations);
1192 P_SCHEDSTAT(nr_wakeups);
1193 P_SCHEDSTAT(nr_wakeups_sync);
1194 P_SCHEDSTAT(nr_wakeups_migrate);
1195 P_SCHEDSTAT(nr_wakeups_local);
1196 P_SCHEDSTAT(nr_wakeups_remote);
1197 P_SCHEDSTAT(nr_wakeups_affine);
1198 P_SCHEDSTAT(nr_wakeups_affine_attempts);
1199 P_SCHEDSTAT(nr_wakeups_passive);
1200 P_SCHEDSTAT(nr_wakeups_idle);
1201
1202 avg_atom = p->se.sum_exec_runtime;
1203 if (nr_switches)
1204 avg_atom = div64_ul(avg_atom, nr_switches);
1205 else
1206 avg_atom = -1LL;
1207
1208 avg_per_cpu = p->se.sum_exec_runtime;
1209 if (p->se.nr_migrations) {
1210 avg_per_cpu = div64_u64(avg_per_cpu,
1211 p->se.nr_migrations);
1212 } else {
1213 avg_per_cpu = -1LL;
1214 }
1215
1216 __PN(avg_atom);
1217 __PN(avg_per_cpu);
1218
1219 #ifdef CONFIG_SCHED_CORE
1220 PN_SCHEDSTAT(core_forceidle_sum);
1221 #endif
1222 }
1223
1224 __P(nr_switches);
1225 __PS("nr_voluntary_switches", p->nvcsw);
1226 __PS("nr_involuntary_switches", p->nivcsw);
1227
1228 P(se.load.weight);
1229 P(se.avg.load_sum);
1230 P(se.avg.runnable_sum);
1231 P(se.avg.util_sum);
1232 P(se.avg.load_avg);
1233 P(se.avg.runnable_avg);
1234 P(se.avg.util_avg);
1235 P(se.avg.last_update_time);
1236 PM(se.avg.util_est, ~UTIL_AVG_UNCHANGED);
1237 #ifdef CONFIG_UCLAMP_TASK
1238 __PS("uclamp.min", p->uclamp_req[UCLAMP_MIN].value);
1239 __PS("uclamp.max", p->uclamp_req[UCLAMP_MAX].value);
1240 __PS("effective uclamp.min", uclamp_eff_value(p, UCLAMP_MIN));
1241 __PS("effective uclamp.max", uclamp_eff_value(p, UCLAMP_MAX));
1242 #endif /* CONFIG_UCLAMP_TASK */
1243 P(policy);
1244 P(prio);
1245 if (task_has_dl_policy(p)) {
1246 P(dl.runtime);
1247 P(dl.deadline);
1248 } else if (fair_policy(p->policy)) {
1249 P(se.slice);
1250 }
1251 #ifdef CONFIG_SCHED_CLASS_EXT
1252 __PS("ext.enabled", task_on_scx(p));
1253 #endif
1254 #undef PN_SCHEDSTAT
1255 #undef P_SCHEDSTAT
1256
1257 {
1258 unsigned int this_cpu = raw_smp_processor_id();
1259 u64 t0, t1;
1260
1261 t0 = cpu_clock(this_cpu);
1262 t1 = cpu_clock(this_cpu);
1263 __PS("clock-delta", t1-t0);
1264 }
1265
1266 sched_show_numa(p, m);
1267 }
1268
proc_sched_set_task(struct task_struct * p)1269 void proc_sched_set_task(struct task_struct *p)
1270 {
1271 #ifdef CONFIG_SCHEDSTATS
1272 memset(&p->stats, 0, sizeof(p->stats));
1273 #endif
1274 }
1275
resched_latency_warn(int cpu,u64 latency)1276 void resched_latency_warn(int cpu, u64 latency)
1277 {
1278 static DEFINE_RATELIMIT_STATE(latency_check_ratelimit, 60 * 60 * HZ, 1);
1279
1280 if (likely(!__ratelimit(&latency_check_ratelimit)))
1281 return;
1282
1283 pr_err("sched: CPU %d need_resched set for > %llu ns (%d ticks) without schedule\n",
1284 cpu, latency, cpu_rq(cpu)->ticks_without_resched);
1285 dump_stack();
1286 }
1287