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v6.13.7
   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, "NO_");
  63		seq_printf(m, "%s ", sched_feat_names[i]);
  64	}
  65	seq_puts(m, "\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(&sched_feat_keys[i]);
  87}
  88
  89static void sched_feat_enable(int i)
  90{
  91	static_key_enable_cpuslocked(&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(sched_feat_names, __SCHED_FEAT_NR, 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(&buf, ubuf, cnt))
 136		return -EFAULT;
 137
 138	buf[cnt] = 0;
 139	cmp = strstrip(buf);
 140
 141	/* Ensure the static_key remains in a consistent state */
 142	inode = file_inode(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(&buf, ubuf, cnt))
 181		return -EFAULT;
 182	buf[cnt] = '\0';
 183
 184	if (kstrtouint(buf, 10, &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, "%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(&buf, ubuf, cnt))
 231		return -EFAULT;
 232
 233	buf[cnt] = 0;
 234	mode = sched_dynamic_mode(strstrip(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", "lazy",
 249	};
 250	int j = ARRAY_SIZE(preempt_modes) - !IS_ENABLED(CONFIG_ARCH_HAS_PREEMPT_LAZY);
 251	int i = IS_ENABLED(CONFIG_PREEMPT_RT) * 2;
 252
 253	for (; i < j; i++) {
 254		if (preempt_dynamic_mode == i)
 255			seq_puts(m, "(");
 256		seq_puts(m, preempt_modes[i]);
 257		if (preempt_dynamic_mode == i)
 258			seq_puts(m, ")");
 259
 260		seq_puts(m, " ");
 261	}
 262
 263	seq_puts(m, "\n");
 264	return 0;
 265}
 266
 267static int sched_dynamic_open(struct inode *inode, struct file *filp)
 268{
 269	return single_open(filp, sched_dynamic_show, NULL);
 270}
 271
 272static const struct file_operations sched_dynamic_fops = {
 273	.open		= sched_dynamic_open,
 274	.write		= sched_dynamic_write,
 275	.read		= seq_read,
 276	.llseek		= seq_lseek,
 277	.release	= single_release,
 278};
 279
 280#endif /* CONFIG_PREEMPT_DYNAMIC */
 281
 282__read_mostly bool sched_debug_verbose;
 283
 284#ifdef CONFIG_SMP
 285static struct dentry           *sd_dentry;
 286
 287
 288static 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	mutex_lock(&sched_domains_mutex);
 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	mutex_unlock(&sched_domains_mutex);
 308	cpus_read_unlock();
 309
 310	return result;
 311}
 312#else
 313#define sched_verbose_write debugfs_write_file_bool
 314#endif
 315
 316static const struct file_operations sched_verbose_fops = {
 317	.read =         debugfs_read_file_bool,
 318	.write =        sched_verbose_write,
 319	.open =         simple_open,
 320	.llseek =       default_llseek,
 321};
 322
 323static const struct seq_operations sched_debug_sops;
 324
 325static int sched_debug_open(struct inode *inode, struct file *filp)
 326{
 327	return seq_open(filp, &sched_debug_sops);
 328}
 329
 330static const struct file_operations sched_debug_fops = {
 331	.open		= sched_debug_open,
 332	.read		= seq_read,
 333	.llseek		= seq_lseek,
 334	.release	= seq_release,
 335};
 336
 337enum dl_param {
 338	DL_RUNTIME = 0,
 339	DL_PERIOD,
 340};
 341
 342static unsigned long fair_server_period_max = (1UL << 22) * NSEC_PER_USEC; /* ~4 seconds */
 343static unsigned long fair_server_period_min = (100) * NSEC_PER_USEC;     /* 100 us */
 344
 345static ssize_t sched_fair_server_write(struct file *filp, const char __user *ubuf,
 346				       size_t cnt, loff_t *ppos, enum dl_param param)
 347{
 348	long cpu = (long) ((struct seq_file *) filp->private_data)->private;
 349	struct rq *rq = cpu_rq(cpu);
 350	u64 runtime, period;
 351	size_t err;
 352	int retval;
 353	u64 value;
 354
 355	err = kstrtoull_from_user(ubuf, cnt, 10, &value);
 356	if (err)
 357		return err;
 358
 359	scoped_guard (rq_lock_irqsave, rq) {
 360		runtime  = rq->fair_server.dl_runtime;
 361		period = rq->fair_server.dl_period;
 362
 363		switch (param) {
 364		case DL_RUNTIME:
 365			if (runtime == value)
 366				break;
 367			runtime = value;
 368			break;
 369		case DL_PERIOD:
 370			if (value == period)
 371				break;
 372			period = value;
 373			break;
 374		}
 375
 376		if (runtime > period ||
 377		    period > fair_server_period_max ||
 378		    period < fair_server_period_min) {
 379			return  -EINVAL;
 380		}
 381
 382		if (rq->cfs.h_nr_running) {
 383			update_rq_clock(rq);
 384			dl_server_stop(&rq->fair_server);
 385		}
 386
 387		retval = dl_server_apply_params(&rq->fair_server, runtime, period, 0);
 388		if (retval)
 389			cnt = retval;
 390
 391		if (!runtime)
 392			printk_deferred("Fair server disabled in CPU %d, system may crash due to starvation.\n",
 393					cpu_of(rq));
 394
 395		if (rq->cfs.h_nr_running)
 396			dl_server_start(&rq->fair_server);
 397	}
 398
 399	*ppos += cnt;
 400	return cnt;
 401}
 402
 403static size_t sched_fair_server_show(struct seq_file *m, void *v, enum dl_param param)
 404{
 405	unsigned long cpu = (unsigned long) m->private;
 406	struct rq *rq = cpu_rq(cpu);
 407	u64 value;
 408
 409	switch (param) {
 410	case DL_RUNTIME:
 411		value = rq->fair_server.dl_runtime;
 412		break;
 413	case DL_PERIOD:
 414		value = rq->fair_server.dl_period;
 415		break;
 416	}
 417
 418	seq_printf(m, "%llu\n", value);
 419	return 0;
 420
 421}
 422
 423static ssize_t
 424sched_fair_server_runtime_write(struct file *filp, const char __user *ubuf,
 425				size_t cnt, loff_t *ppos)
 426{
 427	return sched_fair_server_write(filp, ubuf, cnt, ppos, DL_RUNTIME);
 428}
 429
 430static int sched_fair_server_runtime_show(struct seq_file *m, void *v)
 431{
 432	return sched_fair_server_show(m, v, DL_RUNTIME);
 433}
 434
 435static int sched_fair_server_runtime_open(struct inode *inode, struct file *filp)
 436{
 437	return single_open(filp, sched_fair_server_runtime_show, inode->i_private);
 438}
 439
 440static const struct file_operations fair_server_runtime_fops = {
 441	.open		= sched_fair_server_runtime_open,
 442	.write		= sched_fair_server_runtime_write,
 443	.read		= seq_read,
 444	.llseek		= seq_lseek,
 445	.release	= single_release,
 446};
 447
 448static ssize_t
 449sched_fair_server_period_write(struct file *filp, const char __user *ubuf,
 450			       size_t cnt, loff_t *ppos)
 451{
 452	return sched_fair_server_write(filp, ubuf, cnt, ppos, DL_PERIOD);
 453}
 454
 455static int sched_fair_server_period_show(struct seq_file *m, void *v)
 456{
 457	return sched_fair_server_show(m, v, DL_PERIOD);
 458}
 459
 460static int sched_fair_server_period_open(struct inode *inode, struct file *filp)
 461{
 462	return single_open(filp, sched_fair_server_period_show, inode->i_private);
 463}
 464
 465static const struct file_operations fair_server_period_fops = {
 466	.open		= sched_fair_server_period_open,
 467	.write		= sched_fair_server_period_write,
 468	.read		= seq_read,
 469	.llseek		= seq_lseek,
 470	.release	= single_release,
 471};
 472
 473static struct dentry *debugfs_sched;
 474
 475static void debugfs_fair_server_init(void)
 476{
 477	struct dentry *d_fair;
 478	unsigned long cpu;
 479
 480	d_fair = debugfs_create_dir("fair_server", debugfs_sched);
 481	if (!d_fair)
 482		return;
 483
 484	for_each_possible_cpu(cpu) {
 485		struct dentry *d_cpu;
 486		char buf[32];
 487
 488		snprintf(buf, sizeof(buf), "cpu%lu", cpu);
 489		d_cpu = debugfs_create_dir(buf, d_fair);
 490
 491		debugfs_create_file("runtime", 0644, d_cpu, (void *) cpu, &fair_server_runtime_fops);
 492		debugfs_create_file("period", 0644, d_cpu, (void *) cpu, &fair_server_period_fops);
 493	}
 494}
 495
 496static __init int sched_init_debug(void)
 497{
 498	struct dentry __maybe_unused *numa;
 499
 500	debugfs_sched = debugfs_create_dir("sched", NULL);
 501
 502	debugfs_create_file("features", 0644, debugfs_sched, NULL, &sched_feat_fops);
 503	debugfs_create_file_unsafe("verbose", 0644, debugfs_sched, &sched_debug_verbose, &sched_verbose_fops);
 504#ifdef CONFIG_PREEMPT_DYNAMIC
 505	debugfs_create_file("preempt", 0644, debugfs_sched, NULL, &sched_dynamic_fops);
 506#endif
 507
 508	debugfs_create_u32("base_slice_ns", 0644, debugfs_sched, &sysctl_sched_base_slice);
 509
 510	debugfs_create_u32("latency_warn_ms", 0644, debugfs_sched, &sysctl_resched_latency_warn_ms);
 511	debugfs_create_u32("latency_warn_once", 0644, debugfs_sched, &sysctl_resched_latency_warn_once);
 512
 513#ifdef CONFIG_SMP
 514	debugfs_create_file("tunable_scaling", 0644, debugfs_sched, NULL, &sched_scaling_fops);
 515	debugfs_create_u32("migration_cost_ns", 0644, debugfs_sched, &sysctl_sched_migration_cost);
 516	debugfs_create_u32("nr_migrate", 0644, debugfs_sched, &sysctl_sched_nr_migrate);
 517
 518	mutex_lock(&sched_domains_mutex);
 519	update_sched_domain_debugfs();
 520	mutex_unlock(&sched_domains_mutex);
 521#endif
 522
 523#ifdef CONFIG_NUMA_BALANCING
 524	numa = debugfs_create_dir("numa_balancing", debugfs_sched);
 525
 526	debugfs_create_u32("scan_delay_ms", 0644, numa, &sysctl_numa_balancing_scan_delay);
 527	debugfs_create_u32("scan_period_min_ms", 0644, numa, &sysctl_numa_balancing_scan_period_min);
 528	debugfs_create_u32("scan_period_max_ms", 0644, numa, &sysctl_numa_balancing_scan_period_max);
 529	debugfs_create_u32("scan_size_mb", 0644, numa, &sysctl_numa_balancing_scan_size);
 530	debugfs_create_u32("hot_threshold_ms", 0644, numa, &sysctl_numa_balancing_hot_threshold);
 531#endif
 532
 533	debugfs_create_file("debug", 0444, debugfs_sched, NULL, &sched_debug_fops);
 534
 535	debugfs_fair_server_init();
 536
 537	return 0;
 538}
 539late_initcall(sched_init_debug);
 540
 541#ifdef CONFIG_SMP
 542
 543static cpumask_var_t		sd_sysctl_cpus;
 544
 545static int sd_flags_show(struct seq_file *m, void *v)
 546{
 547	unsigned long flags = *(unsigned int *)m->private;
 548	int idx;
 549
 550	for_each_set_bit(idx, &flags, __SD_FLAG_CNT) {
 551		seq_puts(m, sd_flag_debug[idx].name);
 552		seq_puts(m, " ");
 553	}
 554	seq_puts(m, "\n");
 555
 556	return 0;
 557}
 558
 559static int sd_flags_open(struct inode *inode, struct file *file)
 560{
 561	return single_open(file, sd_flags_show, inode->i_private);
 562}
 563
 564static const struct file_operations sd_flags_fops = {
 565	.open		= sd_flags_open,
 566	.read		= seq_read,
 567	.llseek		= seq_lseek,
 568	.release	= single_release,
 569};
 570
 571static void register_sd(struct sched_domain *sd, struct dentry *parent)
 572{
 573#define SDM(type, mode, member)	\
 574	debugfs_create_##type(#member, mode, parent, &sd->member)
 575
 576	SDM(ulong, 0644, min_interval);
 577	SDM(ulong, 0644, max_interval);
 578	SDM(u64,   0644, max_newidle_lb_cost);
 579	SDM(u32,   0644, busy_factor);
 580	SDM(u32,   0644, imbalance_pct);
 581	SDM(u32,   0644, cache_nice_tries);
 582	SDM(str,   0444, name);
 583
 584#undef SDM
 585
 586	debugfs_create_file("flags", 0444, parent, &sd->flags, &sd_flags_fops);
 587	debugfs_create_file("groups_flags", 0444, parent, &sd->groups->flags, &sd_flags_fops);
 588	debugfs_create_u32("level", 0444, parent, (u32 *)&sd->level);
 589}
 590
 591void update_sched_domain_debugfs(void)
 592{
 593	int cpu, i;
 594
 595	/*
 596	 * This can unfortunately be invoked before sched_debug_init() creates
 597	 * the debug directory. Don't touch sd_sysctl_cpus until then.
 598	 */
 599	if (!debugfs_sched)
 600		return;
 601
 602	if (!sched_debug_verbose)
 603		return;
 604
 605	if (!cpumask_available(sd_sysctl_cpus)) {
 606		if (!alloc_cpumask_var(&sd_sysctl_cpus, GFP_KERNEL))
 607			return;
 608		cpumask_copy(sd_sysctl_cpus, cpu_possible_mask);
 609	}
 610
 611	if (!sd_dentry) {
 612		sd_dentry = debugfs_create_dir("domains", debugfs_sched);
 613
 614		/* rebuild sd_sysctl_cpus if empty since it gets cleared below */
 615		if (cpumask_empty(sd_sysctl_cpus))
 616			cpumask_copy(sd_sysctl_cpus, cpu_online_mask);
 617	}
 618
 619	for_each_cpu(cpu, sd_sysctl_cpus) {
 620		struct sched_domain *sd;
 621		struct dentry *d_cpu;
 622		char buf[32];
 623
 624		snprintf(buf, sizeof(buf), "cpu%d", cpu);
 625		debugfs_lookup_and_remove(buf, sd_dentry);
 626		d_cpu = debugfs_create_dir(buf, sd_dentry);
 627
 628		i = 0;
 629		for_each_domain(cpu, sd) {
 630			struct dentry *d_sd;
 631
 632			snprintf(buf, sizeof(buf), "domain%d", i);
 633			d_sd = debugfs_create_dir(buf, d_cpu);
 634
 635			register_sd(sd, d_sd);
 636			i++;
 637		}
 638
 639		__cpumask_clear_cpu(cpu, sd_sysctl_cpus);
 640	}
 641}
 642
 643void dirty_sched_domain_sysctl(int cpu)
 644{
 645	if (cpumask_available(sd_sysctl_cpus))
 646		__cpumask_set_cpu(cpu, sd_sysctl_cpus);
 647}
 648
 649#endif /* CONFIG_SMP */
 650
 651#ifdef CONFIG_FAIR_GROUP_SCHED
 652static void print_cfs_group_stats(struct seq_file *m, int cpu, struct task_group *tg)
 653{
 654	struct sched_entity *se = tg->se[cpu];
 655
 656#define P(F)		SEQ_printf(m, "  .%-30s: %lld\n",	#F, (long long)F)
 657#define P_SCHEDSTAT(F)	SEQ_printf(m, "  .%-30s: %lld\n",	\
 658		#F, (long long)schedstat_val(stats->F))
 659#define PN(F)		SEQ_printf(m, "  .%-30s: %lld.%06ld\n", #F, SPLIT_NS((long long)F))
 660#define PN_SCHEDSTAT(F)	SEQ_printf(m, "  .%-30s: %lld.%06ld\n", \
 661		#F, SPLIT_NS((long long)schedstat_val(stats->F)))
 662
 663	if (!se)
 664		return;
 665
 666	PN(se->exec_start);
 667	PN(se->vruntime);
 668	PN(se->sum_exec_runtime);
 669
 670	if (schedstat_enabled()) {
 671		struct sched_statistics *stats;
 672		stats = __schedstats_from_se(se);
 673
 674		PN_SCHEDSTAT(wait_start);
 675		PN_SCHEDSTAT(sleep_start);
 676		PN_SCHEDSTAT(block_start);
 677		PN_SCHEDSTAT(sleep_max);
 678		PN_SCHEDSTAT(block_max);
 679		PN_SCHEDSTAT(exec_max);
 680		PN_SCHEDSTAT(slice_max);
 681		PN_SCHEDSTAT(wait_max);
 682		PN_SCHEDSTAT(wait_sum);
 683		P_SCHEDSTAT(wait_count);
 684	}
 685
 686	P(se->load.weight);
 687#ifdef CONFIG_SMP
 688	P(se->avg.load_avg);
 689	P(se->avg.util_avg);
 690	P(se->avg.runnable_avg);
 691#endif
 692
 693#undef PN_SCHEDSTAT
 694#undef PN
 695#undef P_SCHEDSTAT
 696#undef P
 697}
 698#endif
 699
 700#ifdef CONFIG_CGROUP_SCHED
 701static DEFINE_SPINLOCK(sched_debug_lock);
 702static char group_path[PATH_MAX];
 703
 704static void task_group_path(struct task_group *tg, char *path, int plen)
 705{
 706	if (autogroup_path(tg, path, plen))
 707		return;
 708
 709	cgroup_path(tg->css.cgroup, path, plen);
 710}
 711
 712/*
 713 * Only 1 SEQ_printf_task_group_path() caller can use the full length
 714 * group_path[] for cgroup path. Other simultaneous callers will have
 715 * to use a shorter stack buffer. A "..." suffix is appended at the end
 716 * of the stack buffer so that it will show up in case the output length
 717 * matches the given buffer size to indicate possible path name truncation.
 718 */
 719#define SEQ_printf_task_group_path(m, tg, fmt...)			\
 720{									\
 721	if (spin_trylock(&sched_debug_lock)) {				\
 722		task_group_path(tg, group_path, sizeof(group_path));	\
 723		SEQ_printf(m, fmt, group_path);				\
 724		spin_unlock(&sched_debug_lock);				\
 725	} else {							\
 726		char buf[128];						\
 727		char *bufend = buf + sizeof(buf) - 3;			\
 728		task_group_path(tg, buf, bufend - buf);			\
 729		strcpy(bufend - 1, "...");				\
 730		SEQ_printf(m, fmt, buf);				\
 731	}								\
 732}
 733#endif
 734
 735static void
 736print_task(struct seq_file *m, struct rq *rq, struct task_struct *p)
 737{
 738	if (task_current(rq, p))
 739		SEQ_printf(m, ">R");
 740	else
 741		SEQ_printf(m, " %c", task_state_to_char(p));
 742
 743	SEQ_printf(m, " %15s %5d %9Ld.%06ld   %c   %9Ld.%06ld %c %9Ld.%06ld %9Ld.%06ld %9Ld   %5d ",
 744		p->comm, task_pid_nr(p),
 745		SPLIT_NS(p->se.vruntime),
 746		entity_eligible(cfs_rq_of(&p->se), &p->se) ? 'E' : 'N',
 747		SPLIT_NS(p->se.deadline),
 748		p->se.custom_slice ? 'S' : ' ',
 749		SPLIT_NS(p->se.slice),
 750		SPLIT_NS(p->se.sum_exec_runtime),
 751		(long long)(p->nvcsw + p->nivcsw),
 752		p->prio);
 753
 754	SEQ_printf(m, "%9lld.%06ld %9lld.%06ld %9lld.%06ld",
 755		SPLIT_NS(schedstat_val_or_zero(p->stats.wait_sum)),
 
 756		SPLIT_NS(schedstat_val_or_zero(p->stats.sum_sleep_runtime)),
 757		SPLIT_NS(schedstat_val_or_zero(p->stats.sum_block_runtime)));
 758
 759#ifdef CONFIG_NUMA_BALANCING
 760	SEQ_printf(m, "   %d      %d", task_node(p), task_numa_group_id(p));
 761#endif
 762#ifdef CONFIG_CGROUP_SCHED
 763	SEQ_printf_task_group_path(m, task_group(p), "        %s")
 764#endif
 765
 766	SEQ_printf(m, "\n");
 767}
 768
 769static void print_rq(struct seq_file *m, struct rq *rq, int rq_cpu)
 770{
 771	struct task_struct *g, *p;
 772
 773	SEQ_printf(m, "\n");
 774	SEQ_printf(m, "runnable tasks:\n");
 775	SEQ_printf(m, " S            task   PID       vruntime   eligible    "
 776		   "deadline             slice          sum-exec      switches  "
 777		   "prio         wait-time        sum-sleep       sum-block"
 778#ifdef CONFIG_NUMA_BALANCING
 779		   "  node   group-id"
 780#endif
 781#ifdef CONFIG_CGROUP_SCHED
 782		   "  group-path"
 783#endif
 784		   "\n");
 785	SEQ_printf(m, "-------------------------------------------------------"
 786		   "------------------------------------------------------"
 787		   "------------------------------------------------------"
 788#ifdef CONFIG_NUMA_BALANCING
 789		   "--------------"
 790#endif
 791#ifdef CONFIG_CGROUP_SCHED
 792		   "--------------"
 793#endif
 794		   "\n");
 795
 796	rcu_read_lock();
 797	for_each_process_thread(g, p) {
 798		if (task_cpu(p) != rq_cpu)
 799			continue;
 800
 801		print_task(m, rq, p);
 802	}
 803	rcu_read_unlock();
 804}
 805
 806void print_cfs_rq(struct seq_file *m, int cpu, struct cfs_rq *cfs_rq)
 807{
 808	s64 left_vruntime = -1, min_vruntime, right_vruntime = -1, left_deadline = -1, spread;
 809	struct sched_entity *last, *first, *root;
 810	struct rq *rq = cpu_rq(cpu);
 811	unsigned long flags;
 812
 813#ifdef CONFIG_FAIR_GROUP_SCHED
 814	SEQ_printf(m, "\n");
 815	SEQ_printf_task_group_path(m, cfs_rq->tg, "cfs_rq[%d]:%s\n", cpu);
 816#else
 817	SEQ_printf(m, "\n");
 818	SEQ_printf(m, "cfs_rq[%d]:\n", cpu);
 819#endif
 
 
 820
 821	raw_spin_rq_lock_irqsave(rq, flags);
 822	root = __pick_root_entity(cfs_rq);
 823	if (root)
 824		left_vruntime = root->min_vruntime;
 825	first = __pick_first_entity(cfs_rq);
 826	if (first)
 827		left_deadline = first->deadline;
 828	last = __pick_last_entity(cfs_rq);
 829	if (last)
 830		right_vruntime = last->vruntime;
 831	min_vruntime = cfs_rq->min_vruntime;
 832	raw_spin_rq_unlock_irqrestore(rq, flags);
 833
 834	SEQ_printf(m, "  .%-30s: %Ld.%06ld\n", "left_deadline",
 835			SPLIT_NS(left_deadline));
 836	SEQ_printf(m, "  .%-30s: %Ld.%06ld\n", "left_vruntime",
 837			SPLIT_NS(left_vruntime));
 838	SEQ_printf(m, "  .%-30s: %Ld.%06ld\n", "min_vruntime",
 839			SPLIT_NS(min_vruntime));
 840	SEQ_printf(m, "  .%-30s: %Ld.%06ld\n", "avg_vruntime",
 841			SPLIT_NS(avg_vruntime(cfs_rq)));
 842	SEQ_printf(m, "  .%-30s: %Ld.%06ld\n", "right_vruntime",
 843			SPLIT_NS(right_vruntime));
 844	spread = right_vruntime - left_vruntime;
 845	SEQ_printf(m, "  .%-30s: %Ld.%06ld\n", "spread", SPLIT_NS(spread));
 
 
 846	SEQ_printf(m, "  .%-30s: %d\n", "nr_running", cfs_rq->nr_running);
 847	SEQ_printf(m, "  .%-30s: %d\n", "h_nr_running", cfs_rq->h_nr_running);
 848	SEQ_printf(m, "  .%-30s: %d\n", "h_nr_delayed", cfs_rq->h_nr_delayed);
 849	SEQ_printf(m, "  .%-30s: %d\n", "idle_nr_running",
 850			cfs_rq->idle_nr_running);
 851	SEQ_printf(m, "  .%-30s: %d\n", "idle_h_nr_running",
 852			cfs_rq->idle_h_nr_running);
 853	SEQ_printf(m, "  .%-30s: %ld\n", "load", cfs_rq->load.weight);
 854#ifdef CONFIG_SMP
 855	SEQ_printf(m, "  .%-30s: %lu\n", "load_avg",
 856			cfs_rq->avg.load_avg);
 857	SEQ_printf(m, "  .%-30s: %lu\n", "runnable_avg",
 858			cfs_rq->avg.runnable_avg);
 859	SEQ_printf(m, "  .%-30s: %lu\n", "util_avg",
 860			cfs_rq->avg.util_avg);
 861	SEQ_printf(m, "  .%-30s: %u\n", "util_est",
 862			cfs_rq->avg.util_est);
 863	SEQ_printf(m, "  .%-30s: %ld\n", "removed.load_avg",
 864			cfs_rq->removed.load_avg);
 865	SEQ_printf(m, "  .%-30s: %ld\n", "removed.util_avg",
 866			cfs_rq->removed.util_avg);
 867	SEQ_printf(m, "  .%-30s: %ld\n", "removed.runnable_avg",
 868			cfs_rq->removed.runnable_avg);
 869#ifdef CONFIG_FAIR_GROUP_SCHED
 870	SEQ_printf(m, "  .%-30s: %lu\n", "tg_load_avg_contrib",
 871			cfs_rq->tg_load_avg_contrib);
 872	SEQ_printf(m, "  .%-30s: %ld\n", "tg_load_avg",
 873			atomic_long_read(&cfs_rq->tg->load_avg));
 874#endif
 875#endif
 876#ifdef CONFIG_CFS_BANDWIDTH
 877	SEQ_printf(m, "  .%-30s: %d\n", "throttled",
 878			cfs_rq->throttled);
 879	SEQ_printf(m, "  .%-30s: %d\n", "throttle_count",
 880			cfs_rq->throttle_count);
 881#endif
 882
 883#ifdef CONFIG_FAIR_GROUP_SCHED
 884	print_cfs_group_stats(m, cpu, cfs_rq->tg);
 885#endif
 886}
 887
 888void print_rt_rq(struct seq_file *m, int cpu, struct rt_rq *rt_rq)
 889{
 890#ifdef CONFIG_RT_GROUP_SCHED
 891	SEQ_printf(m, "\n");
 892	SEQ_printf_task_group_path(m, rt_rq->tg, "rt_rq[%d]:%s\n", cpu);
 893#else
 894	SEQ_printf(m, "\n");
 895	SEQ_printf(m, "rt_rq[%d]:\n", cpu);
 896#endif
 897
 898#define P(x) \
 899	SEQ_printf(m, "  .%-30s: %Ld\n", #x, (long long)(rt_rq->x))
 900#define PU(x) \
 901	SEQ_printf(m, "  .%-30s: %lu\n", #x, (unsigned long)(rt_rq->x))
 902#define PN(x) \
 903	SEQ_printf(m, "  .%-30s: %Ld.%06ld\n", #x, SPLIT_NS(rt_rq->x))
 904
 905	PU(rt_nr_running);
 906
 907#ifdef CONFIG_RT_GROUP_SCHED
 908	P(rt_throttled);
 909	PN(rt_time);
 910	PN(rt_runtime);
 911#endif
 912
 913#undef PN
 914#undef PU
 915#undef P
 916}
 917
 918void print_dl_rq(struct seq_file *m, int cpu, struct dl_rq *dl_rq)
 919{
 920	struct dl_bw *dl_bw;
 921
 922	SEQ_printf(m, "\n");
 923	SEQ_printf(m, "dl_rq[%d]:\n", cpu);
 924
 925#define PU(x) \
 926	SEQ_printf(m, "  .%-30s: %lu\n", #x, (unsigned long)(dl_rq->x))
 927
 928	PU(dl_nr_running);
 929#ifdef CONFIG_SMP
 930	dl_bw = &cpu_rq(cpu)->rd->dl_bw;
 931#else
 932	dl_bw = &dl_rq->dl_bw;
 933#endif
 934	SEQ_printf(m, "  .%-30s: %lld\n", "dl_bw->bw", dl_bw->bw);
 935	SEQ_printf(m, "  .%-30s: %lld\n", "dl_bw->total_bw", dl_bw->total_bw);
 936
 937#undef PU
 938}
 939
 940static void print_cpu(struct seq_file *m, int cpu)
 941{
 942	struct rq *rq = cpu_rq(cpu);
 943
 944#ifdef CONFIG_X86
 945	{
 946		unsigned int freq = cpu_khz ? : 1;
 947
 948		SEQ_printf(m, "cpu#%d, %u.%03u MHz\n",
 949			   cpu, freq / 1000, (freq % 1000));
 950	}
 951#else
 952	SEQ_printf(m, "cpu#%d\n", cpu);
 953#endif
 954
 955#define P(x)								\
 956do {									\
 957	if (sizeof(rq->x) == 4)						\
 958		SEQ_printf(m, "  .%-30s: %d\n", #x, (int)(rq->x));	\
 959	else								\
 960		SEQ_printf(m, "  .%-30s: %Ld\n", #x, (long long)(rq->x));\
 961} while (0)
 962
 963#define PN(x) \
 964	SEQ_printf(m, "  .%-30s: %Ld.%06ld\n", #x, SPLIT_NS(rq->x))
 965
 966	P(nr_running);
 967	P(nr_switches);
 968	P(nr_uninterruptible);
 969	PN(next_balance);
 970	SEQ_printf(m, "  .%-30s: %ld\n", "curr->pid", (long)(task_pid_nr(rq->curr)));
 971	PN(clock);
 972	PN(clock_task);
 973#undef P
 974#undef PN
 975
 976#ifdef CONFIG_SMP
 977#define P64(n) SEQ_printf(m, "  .%-30s: %Ld\n", #n, rq->n);
 978	P64(avg_idle);
 979	P64(max_idle_balance_cost);
 980#undef P64
 981#endif
 982
 983#define P(n) SEQ_printf(m, "  .%-30s: %d\n", #n, schedstat_val(rq->n));
 984	if (schedstat_enabled()) {
 985		P(yld_count);
 986		P(sched_count);
 987		P(sched_goidle);
 988		P(ttwu_count);
 989		P(ttwu_local);
 990	}
 991#undef P
 992
 993	print_cfs_stats(m, cpu);
 994	print_rt_stats(m, cpu);
 995	print_dl_stats(m, cpu);
 996
 997	print_rq(m, rq, cpu);
 998	SEQ_printf(m, "\n");
 999}
1000
1001static const char *sched_tunable_scaling_names[] = {
1002	"none",
1003	"logarithmic",
1004	"linear"
1005};
1006
1007static void sched_debug_header(struct seq_file *m)
1008{
1009	u64 ktime, sched_clk, cpu_clk;
1010	unsigned long flags;
1011
1012	local_irq_save(flags);
1013	ktime = ktime_to_ns(ktime_get());
1014	sched_clk = sched_clock();
1015	cpu_clk = local_clock();
1016	local_irq_restore(flags);
1017
1018	SEQ_printf(m, "Sched Debug Version: v0.11, %s %.*s\n",
1019		init_utsname()->release,
1020		(int)strcspn(init_utsname()->version, " "),
1021		init_utsname()->version);
1022
1023#define P(x) \
1024	SEQ_printf(m, "%-40s: %Ld\n", #x, (long long)(x))
1025#define PN(x) \
1026	SEQ_printf(m, "%-40s: %Ld.%06ld\n", #x, SPLIT_NS(x))
1027	PN(ktime);
1028	PN(sched_clk);
1029	PN(cpu_clk);
1030	P(jiffies);
1031#ifdef CONFIG_HAVE_UNSTABLE_SCHED_CLOCK
1032	P(sched_clock_stable());
1033#endif
1034#undef PN
1035#undef P
1036
1037	SEQ_printf(m, "\n");
1038	SEQ_printf(m, "sysctl_sched\n");
1039
1040#define P(x) \
1041	SEQ_printf(m, "  .%-40s: %Ld\n", #x, (long long)(x))
1042#define PN(x) \
1043	SEQ_printf(m, "  .%-40s: %Ld.%06ld\n", #x, SPLIT_NS(x))
1044	PN(sysctl_sched_base_slice);
1045	P(sysctl_sched_features);
1046#undef PN
1047#undef P
1048
1049	SEQ_printf(m, "  .%-40s: %d (%s)\n",
1050		"sysctl_sched_tunable_scaling",
1051		sysctl_sched_tunable_scaling,
1052		sched_tunable_scaling_names[sysctl_sched_tunable_scaling]);
1053	SEQ_printf(m, "\n");
1054}
1055
1056static int sched_debug_show(struct seq_file *m, void *v)
1057{
1058	int cpu = (unsigned long)(v - 2);
1059
1060	if (cpu != -1)
1061		print_cpu(m, cpu);
1062	else
1063		sched_debug_header(m);
1064
1065	return 0;
1066}
1067
1068void sysrq_sched_debug_show(void)
1069{
1070	int cpu;
1071
1072	sched_debug_header(NULL);
1073	for_each_online_cpu(cpu) {
1074		/*
1075		 * Need to reset softlockup watchdogs on all CPUs, because
1076		 * another CPU might be blocked waiting for us to process
1077		 * an IPI or stop_machine.
1078		 */
1079		touch_nmi_watchdog();
1080		touch_all_softlockup_watchdogs();
1081		print_cpu(NULL, cpu);
1082	}
1083}
1084
1085/*
1086 * This iterator needs some explanation.
1087 * It returns 1 for the header position.
1088 * This means 2 is CPU 0.
1089 * In a hotplugged system some CPUs, including CPU 0, may be missing so we have
1090 * to use cpumask_* to iterate over the CPUs.
1091 */
1092static void *sched_debug_start(struct seq_file *file, loff_t *offset)
1093{
1094	unsigned long n = *offset;
1095
1096	if (n == 0)
1097		return (void *) 1;
1098
1099	n--;
1100
1101	if (n > 0)
1102		n = cpumask_next(n - 1, cpu_online_mask);
1103	else
1104		n = cpumask_first(cpu_online_mask);
1105
1106	*offset = n + 1;
1107
1108	if (n < nr_cpu_ids)
1109		return (void *)(unsigned long)(n + 2);
1110
1111	return NULL;
1112}
1113
1114static void *sched_debug_next(struct seq_file *file, void *data, loff_t *offset)
1115{
1116	(*offset)++;
1117	return sched_debug_start(file, offset);
1118}
1119
1120static void sched_debug_stop(struct seq_file *file, void *data)
1121{
1122}
1123
1124static const struct seq_operations sched_debug_sops = {
1125	.start		= sched_debug_start,
1126	.next		= sched_debug_next,
1127	.stop		= sched_debug_stop,
1128	.show		= sched_debug_show,
1129};
1130
1131#define __PS(S, F) SEQ_printf(m, "%-45s:%21Ld\n", S, (long long)(F))
1132#define __P(F) __PS(#F, F)
1133#define   P(F) __PS(#F, p->F)
1134#define   PM(F, M) __PS(#F, p->F & (M))
1135#define __PSN(S, F) SEQ_printf(m, "%-45s:%14Ld.%06ld\n", S, SPLIT_NS((long long)(F)))
1136#define __PN(F) __PSN(#F, F)
1137#define   PN(F) __PSN(#F, p->F)
1138
1139
1140#ifdef CONFIG_NUMA_BALANCING
1141void print_numa_stats(struct seq_file *m, int node, unsigned long tsf,
1142		unsigned long tpf, unsigned long gsf, unsigned long gpf)
1143{
1144	SEQ_printf(m, "numa_faults node=%d ", node);
1145	SEQ_printf(m, "task_private=%lu task_shared=%lu ", tpf, tsf);
1146	SEQ_printf(m, "group_private=%lu group_shared=%lu\n", gpf, gsf);
1147}
1148#endif
1149
1150
1151static void sched_show_numa(struct task_struct *p, struct seq_file *m)
1152{
1153#ifdef CONFIG_NUMA_BALANCING
1154	if (p->mm)
1155		P(mm->numa_scan_seq);
1156
1157	P(numa_pages_migrated);
1158	P(numa_preferred_nid);
1159	P(total_numa_faults);
1160	SEQ_printf(m, "current_node=%d, numa_group_id=%d\n",
1161			task_node(p), task_numa_group_id(p));
1162	show_numa_stats(p, m);
1163#endif
1164}
1165
1166void proc_sched_show_task(struct task_struct *p, struct pid_namespace *ns,
1167						  struct seq_file *m)
1168{
1169	unsigned long nr_switches;
1170
1171	SEQ_printf(m, "%s (%d, #threads: %d)\n", p->comm, task_pid_nr_ns(p, ns),
1172						get_nr_threads(p));
1173	SEQ_printf(m,
1174		"---------------------------------------------------------"
1175		"----------\n");
1176
1177#define P_SCHEDSTAT(F)  __PS(#F, schedstat_val(p->stats.F))
1178#define PN_SCHEDSTAT(F) __PSN(#F, schedstat_val(p->stats.F))
1179
1180	PN(se.exec_start);
1181	PN(se.vruntime);
1182	PN(se.sum_exec_runtime);
1183
1184	nr_switches = p->nvcsw + p->nivcsw;
1185
1186	P(se.nr_migrations);
1187
1188	if (schedstat_enabled()) {
1189		u64 avg_atom, avg_per_cpu;
1190
1191		PN_SCHEDSTAT(sum_sleep_runtime);
1192		PN_SCHEDSTAT(sum_block_runtime);
1193		PN_SCHEDSTAT(wait_start);
1194		PN_SCHEDSTAT(sleep_start);
1195		PN_SCHEDSTAT(block_start);
1196		PN_SCHEDSTAT(sleep_max);
1197		PN_SCHEDSTAT(block_max);
1198		PN_SCHEDSTAT(exec_max);
1199		PN_SCHEDSTAT(slice_max);
1200		PN_SCHEDSTAT(wait_max);
1201		PN_SCHEDSTAT(wait_sum);
1202		P_SCHEDSTAT(wait_count);
1203		PN_SCHEDSTAT(iowait_sum);
1204		P_SCHEDSTAT(iowait_count);
1205		P_SCHEDSTAT(nr_migrations_cold);
1206		P_SCHEDSTAT(nr_failed_migrations_affine);
1207		P_SCHEDSTAT(nr_failed_migrations_running);
1208		P_SCHEDSTAT(nr_failed_migrations_hot);
1209		P_SCHEDSTAT(nr_forced_migrations);
1210		P_SCHEDSTAT(nr_wakeups);
1211		P_SCHEDSTAT(nr_wakeups_sync);
1212		P_SCHEDSTAT(nr_wakeups_migrate);
1213		P_SCHEDSTAT(nr_wakeups_local);
1214		P_SCHEDSTAT(nr_wakeups_remote);
1215		P_SCHEDSTAT(nr_wakeups_affine);
1216		P_SCHEDSTAT(nr_wakeups_affine_attempts);
1217		P_SCHEDSTAT(nr_wakeups_passive);
1218		P_SCHEDSTAT(nr_wakeups_idle);
1219
1220		avg_atom = p->se.sum_exec_runtime;
1221		if (nr_switches)
1222			avg_atom = div64_ul(avg_atom, nr_switches);
1223		else
1224			avg_atom = -1LL;
1225
1226		avg_per_cpu = p->se.sum_exec_runtime;
1227		if (p->se.nr_migrations) {
1228			avg_per_cpu = div64_u64(avg_per_cpu,
1229						p->se.nr_migrations);
1230		} else {
1231			avg_per_cpu = -1LL;
1232		}
1233
1234		__PN(avg_atom);
1235		__PN(avg_per_cpu);
1236
1237#ifdef CONFIG_SCHED_CORE
1238		PN_SCHEDSTAT(core_forceidle_sum);
1239#endif
1240	}
1241
1242	__P(nr_switches);
1243	__PS("nr_voluntary_switches", p->nvcsw);
1244	__PS("nr_involuntary_switches", p->nivcsw);
1245
1246	P(se.load.weight);
1247#ifdef CONFIG_SMP
1248	P(se.avg.load_sum);
1249	P(se.avg.runnable_sum);
1250	P(se.avg.util_sum);
1251	P(se.avg.load_avg);
1252	P(se.avg.runnable_avg);
1253	P(se.avg.util_avg);
1254	P(se.avg.last_update_time);
1255	PM(se.avg.util_est, ~UTIL_AVG_UNCHANGED);
1256#endif
1257#ifdef CONFIG_UCLAMP_TASK
1258	__PS("uclamp.min", p->uclamp_req[UCLAMP_MIN].value);
1259	__PS("uclamp.max", p->uclamp_req[UCLAMP_MAX].value);
1260	__PS("effective uclamp.min", uclamp_eff_value(p, UCLAMP_MIN));
1261	__PS("effective uclamp.max", uclamp_eff_value(p, UCLAMP_MAX));
1262#endif
1263	P(policy);
1264	P(prio);
1265	if (task_has_dl_policy(p)) {
1266		P(dl.runtime);
1267		P(dl.deadline);
1268	}
1269#ifdef CONFIG_SCHED_CLASS_EXT
1270	__PS("ext.enabled", task_on_scx(p));
1271#endif
1272#undef PN_SCHEDSTAT
1273#undef P_SCHEDSTAT
1274
1275	{
1276		unsigned int this_cpu = raw_smp_processor_id();
1277		u64 t0, t1;
1278
1279		t0 = cpu_clock(this_cpu);
1280		t1 = cpu_clock(this_cpu);
1281		__PS("clock-delta", t1-t0);
1282	}
1283
1284	sched_show_numa(p, m);
1285}
1286
1287void proc_sched_set_task(struct task_struct *p)
1288{
1289#ifdef CONFIG_SCHEDSTATS
1290	memset(&p->stats, 0, sizeof(p->stats));
1291#endif
1292}
1293
1294void resched_latency_warn(int cpu, u64 latency)
1295{
1296	static DEFINE_RATELIMIT_STATE(latency_check_ratelimit, 60 * 60 * HZ, 1);
1297
1298	WARN(__ratelimit(&latency_check_ratelimit),
1299	     "sched: CPU %d need_resched set for > %llu ns (%d ticks) "
1300	     "without schedule\n",
1301	     cpu, latency, cpu_rq(cpu)->ticks_without_resched);
1302}
v6.9.4
   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, "NO_");
  63		seq_printf(m, "%s ", sched_feat_names[i]);
  64	}
  65	seq_puts(m, "\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(&sched_feat_keys[i]);
  87}
  88
  89static void sched_feat_enable(int i)
  90{
  91	static_key_enable_cpuslocked(&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(sched_feat_names, __SCHED_FEAT_NR, 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(&buf, ubuf, cnt))
 136		return -EFAULT;
 137
 138	buf[cnt] = 0;
 139	cmp = strstrip(buf);
 140
 141	/* Ensure the static_key remains in a consistent state */
 142	inode = file_inode(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(&buf, ubuf, cnt))
 181		return -EFAULT;
 182	buf[cnt] = '\0';
 183
 184	if (kstrtouint(buf, 10, &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, "%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(&buf, ubuf, cnt))
 231		return -EFAULT;
 232
 233	buf[cnt] = 0;
 234	mode = sched_dynamic_mode(strstrip(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, "(");
 255		seq_puts(m, preempt_modes[i]);
 256		if (preempt_dynamic_mode == i)
 257			seq_puts(m, ")");
 258
 259		seq_puts(m, " ");
 260	}
 261
 262	seq_puts(m, "\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(filp, ubuf, cnt, ppos);
 298
 299	if (sched_debug_verbose && !orig)
 300		update_sched_domain_debugfs();
 301	else if (!sched_debug_verbose && orig) {
 302		debugfs_remove(sd_dentry);
 303		sd_dentry = NULL;
 304	}
 305
 306	mutex_unlock(&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("sched", NULL);
 343
 344	debugfs_create_file("features", 0644, debugfs_sched, NULL, &sched_feat_fops);
 345	debugfs_create_file_unsafe("verbose", 0644, debugfs_sched, &sched_debug_verbose, &sched_verbose_fops);
 346#ifdef CONFIG_PREEMPT_DYNAMIC
 347	debugfs_create_file("preempt", 0644, debugfs_sched, NULL, &sched_dynamic_fops);
 348#endif
 349
 350	debugfs_create_u32("base_slice_ns", 0644, debugfs_sched, &sysctl_sched_base_slice);
 351
 352	debugfs_create_u32("latency_warn_ms", 0644, debugfs_sched, &sysctl_resched_latency_warn_ms);
 353	debugfs_create_u32("latency_warn_once", 0644, debugfs_sched, &sysctl_resched_latency_warn_once);
 354
 355#ifdef CONFIG_SMP
 356	debugfs_create_file("tunable_scaling", 0644, debugfs_sched, NULL, &sched_scaling_fops);
 357	debugfs_create_u32("migration_cost_ns", 0644, debugfs_sched, &sysctl_sched_migration_cost);
 358	debugfs_create_u32("nr_migrate", 0644, debugfs_sched, &sysctl_sched_nr_migrate);
 359
 360	mutex_lock(&sched_domains_mutex);
 361	update_sched_domain_debugfs();
 362	mutex_unlock(&sched_domains_mutex);
 363#endif
 364
 365#ifdef CONFIG_NUMA_BALANCING
 366	numa = debugfs_create_dir("numa_balancing", debugfs_sched);
 367
 368	debugfs_create_u32("scan_delay_ms", 0644, numa, &sysctl_numa_balancing_scan_delay);
 369	debugfs_create_u32("scan_period_min_ms", 0644, numa, &sysctl_numa_balancing_scan_period_min);
 370	debugfs_create_u32("scan_period_max_ms", 0644, numa, &sysctl_numa_balancing_scan_period_max);
 371	debugfs_create_u32("scan_size_mb", 0644, numa, &sysctl_numa_balancing_scan_size);
 372	debugfs_create_u32("hot_threshold_ms", 0644, numa, &sysctl_numa_balancing_hot_threshold);
 373#endif
 374
 375	debugfs_create_file("debug", 0444, debugfs_sched, NULL, &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, sd_flag_debug[idx].name);
 392		seq_puts(m, " ");
 393	}
 394	seq_puts(m, "\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("flags", 0444, parent, &sd->flags, &sd_flags_fops);
 427	debugfs_create_file("groups_flags", 0444, parent, &sd->groups->flags, &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(sd_sysctl_cpus)) {
 445		if (!alloc_cpumask_var(&sd_sysctl_cpus, GFP_KERNEL))
 446			return;
 447		cpumask_copy(sd_sysctl_cpus, cpu_possible_mask);
 448	}
 449
 450	if (!sd_dentry) {
 451		sd_dentry = debugfs_create_dir("domains", debugfs_sched);
 452
 453		/* rebuild sd_sysctl_cpus if empty since it gets cleared below */
 454		if (cpumask_empty(sd_sysctl_cpus))
 455			cpumask_copy(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, sizeof(buf), "cpu%d", cpu);
 464		debugfs_lookup_and_remove(buf, sd_dentry);
 465		d_cpu = debugfs_create_dir(buf, sd_dentry);
 466
 467		i = 0;
 468		for_each_domain(cpu, sd) {
 469			struct dentry *d_sd;
 470
 471			snprintf(buf, sizeof(buf), "domain%d", i);
 472			d_sd = debugfs_create_dir(buf, d_cpu);
 473
 474			register_sd(sd, d_sd);
 475			i++;
 476		}
 477
 478		__cpumask_clear_cpu(cpu, sd_sysctl_cpus);
 479	}
 480}
 481
 482void dirty_sched_domain_sysctl(int cpu)
 483{
 484	if (cpumask_available(sd_sysctl_cpus))
 485		__cpumask_set_cpu(cpu, 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, path, plen))
 546		return;
 547
 548	cgroup_path(tg->css.cgroup, path, 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, 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, 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(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 - 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(avg_per_cpu,
1052						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(this_cpu);
1100		t1 = cpu_clock(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}