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

source code of linux/kernel/sched/debug.c