1 /*
2 * kernel/time/sched_debug.c
3 *
4 * Print the CFS rbtree
5 *
6 * Copyright(C) 2007, Red Hat, Inc., Ingo Molnar
7 *
8 * This program is free software; you can redistribute it and/or modify
9 * it under the terms of the GNU General Public License version 2 as
10 * published by the Free Software Foundation.
11 */
12
13 #include <linux/proc_fs.h>
14 #include <linux/sched.h>
15 #include <linux/seq_file.h>
16 #include <linux/kallsyms.h>
17 #include <linux/utsname.h>
18
19 static DEFINE_SPINLOCK(sched_debug_lock);
20
21 /*
22 * This allows printing both to /proc/sched_debug and
23 * to the console
24 */
25 #define SEQ_printf(m, x...) \
26 do { \
27 if (m) \
28 seq_printf(m, x); \
29 else \
30 printk(x); \
31 } while (0)
32
33 /*
34 * Ease the printing of nsec fields:
35 */
nsec_high(unsigned long long nsec)36 static long long nsec_high(unsigned long long nsec)
37 {
38 if ((long long)nsec < 0) {
39 nsec = -nsec;
40 do_div(nsec, 1000000);
41 return -nsec;
42 }
43 do_div(nsec, 1000000);
44
45 return nsec;
46 }
47
nsec_low(unsigned long long nsec)48 static unsigned long nsec_low(unsigned long long nsec)
49 {
50 if ((long long)nsec < 0)
51 nsec = -nsec;
52
53 return do_div(nsec, 1000000);
54 }
55
56 #define SPLIT_NS(x) nsec_high(x), nsec_low(x)
57
58 #ifdef CONFIG_FAIR_GROUP_SCHED
print_cfs_group_stats(struct seq_file * m,int cpu,struct task_group * tg)59 static void print_cfs_group_stats(struct seq_file *m, int cpu, struct task_group *tg)
60 {
61 struct sched_entity *se = tg->se[cpu];
62 if (!se)
63 return;
64
65 #define P(F) \
66 SEQ_printf(m, " .%-30s: %lld\n", #F, (long long)F)
67 #define PN(F) \
68 SEQ_printf(m, " .%-30s: %lld.%06ld\n", #F, SPLIT_NS((long long)F))
69
70 PN(se->exec_start);
71 PN(se->vruntime);
72 PN(se->sum_exec_runtime);
73 #ifdef CONFIG_SCHEDSTATS
74 PN(se->statistics.wait_start);
75 PN(se->statistics.sleep_start);
76 PN(se->statistics.block_start);
77 PN(se->statistics.sleep_max);
78 PN(se->statistics.block_max);
79 PN(se->statistics.exec_max);
80 PN(se->statistics.slice_max);
81 PN(se->statistics.wait_max);
82 PN(se->statistics.wait_sum);
83 P(se->statistics.wait_count);
84 #endif
85 P(se->load.weight);
86 #undef PN
87 #undef P
88 }
89 #endif
90
91 #ifdef CONFIG_CGROUP_SCHED
92 static char group_path[PATH_MAX];
93
task_group_path(struct task_group * tg)94 static char *task_group_path(struct task_group *tg)
95 {
96 if (autogroup_path(tg, group_path, PATH_MAX))
97 return group_path;
98
99 /*
100 * May be NULL if the underlying cgroup isn't fully-created yet
101 */
102 if (!tg->css.cgroup) {
103 group_path[0] = '\0';
104 return group_path;
105 }
106 cgroup_path(tg->css.cgroup, group_path, PATH_MAX);
107 return group_path;
108 }
109 #endif
110
111 static void
print_task(struct seq_file * m,struct rq * rq,struct task_struct * p)112 print_task(struct seq_file *m, struct rq *rq, struct task_struct *p)
113 {
114 if (rq->curr == p)
115 SEQ_printf(m, "R");
116 else
117 SEQ_printf(m, " ");
118
119 SEQ_printf(m, "%15s %5d %9Ld.%06ld %9Ld %5d ",
120 p->comm, p->pid,
121 SPLIT_NS(p->se.vruntime),
122 (long long)(p->nvcsw + p->nivcsw),
123 p->prio);
124 #ifdef CONFIG_SCHEDSTATS
125 SEQ_printf(m, "%9Ld.%06ld %9Ld.%06ld %9Ld.%06ld",
126 SPLIT_NS(p->se.vruntime),
127 SPLIT_NS(p->se.sum_exec_runtime),
128 SPLIT_NS(p->se.statistics.sum_sleep_runtime));
129 #else
130 SEQ_printf(m, "%15Ld %15Ld %15Ld.%06ld %15Ld.%06ld %15Ld.%06ld",
131 0LL, 0LL, 0LL, 0L, 0LL, 0L, 0LL, 0L);
132 #endif
133 #ifdef CONFIG_CGROUP_SCHED
134 SEQ_printf(m, " %s", task_group_path(task_group(p)));
135 #endif
136
137 SEQ_printf(m, "\n");
138 }
139
print_rq(struct seq_file * m,struct rq * rq,int rq_cpu)140 static void print_rq(struct seq_file *m, struct rq *rq, int rq_cpu)
141 {
142 struct task_struct *g, *p;
143 unsigned long flags;
144
145 SEQ_printf(m,
146 "\nrunnable tasks:\n"
147 " task PID tree-key switches prio"
148 " exec-runtime sum-exec sum-sleep\n"
149 "------------------------------------------------------"
150 "----------------------------------------------------\n");
151
152 read_lock_irqsave(&tasklist_lock, flags);
153
154 do_each_thread(g, p) {
155 if (!p->se.on_rq || task_cpu(p) != rq_cpu)
156 continue;
157
158 print_task(m, rq, p);
159 } while_each_thread(g, p);
160
161 read_unlock_irqrestore(&tasklist_lock, flags);
162 }
163
print_cfs_rq(struct seq_file * m,int cpu,struct cfs_rq * cfs_rq)164 void print_cfs_rq(struct seq_file *m, int cpu, struct cfs_rq *cfs_rq)
165 {
166 s64 MIN_vruntime = -1, min_vruntime, max_vruntime = -1,
167 spread, rq0_min_vruntime, spread0;
168 struct rq *rq = cpu_rq(cpu);
169 struct sched_entity *last;
170 unsigned long flags;
171
172 #ifdef CONFIG_FAIR_GROUP_SCHED
173 SEQ_printf(m, "\ncfs_rq[%d]:%s\n", cpu, task_group_path(cfs_rq->tg));
174 #else
175 SEQ_printf(m, "\ncfs_rq[%d]:\n", cpu);
176 #endif
177 SEQ_printf(m, " .%-30s: %Ld.%06ld\n", "exec_clock",
178 SPLIT_NS(cfs_rq->exec_clock));
179
180 raw_spin_lock_irqsave(&rq->lock, flags);
181 if (cfs_rq->rb_leftmost)
182 MIN_vruntime = (__pick_first_entity(cfs_rq))->vruntime;
183 last = __pick_last_entity(cfs_rq);
184 if (last)
185 max_vruntime = last->vruntime;
186 min_vruntime = cfs_rq->min_vruntime;
187 rq0_min_vruntime = cpu_rq(0)->cfs.min_vruntime;
188 raw_spin_unlock_irqrestore(&rq->lock, flags);
189 SEQ_printf(m, " .%-30s: %Ld.%06ld\n", "MIN_vruntime",
190 SPLIT_NS(MIN_vruntime));
191 SEQ_printf(m, " .%-30s: %Ld.%06ld\n", "min_vruntime",
192 SPLIT_NS(min_vruntime));
193 SEQ_printf(m, " .%-30s: %Ld.%06ld\n", "max_vruntime",
194 SPLIT_NS(max_vruntime));
195 spread = max_vruntime - MIN_vruntime;
196 SEQ_printf(m, " .%-30s: %Ld.%06ld\n", "spread",
197 SPLIT_NS(spread));
198 spread0 = min_vruntime - rq0_min_vruntime;
199 SEQ_printf(m, " .%-30s: %Ld.%06ld\n", "spread0",
200 SPLIT_NS(spread0));
201 SEQ_printf(m, " .%-30s: %d\n", "nr_spread_over",
202 cfs_rq->nr_spread_over);
203 SEQ_printf(m, " .%-30s: %ld\n", "nr_running", cfs_rq->nr_running);
204 SEQ_printf(m, " .%-30s: %ld\n", "load", cfs_rq->load.weight);
205 #ifdef CONFIG_FAIR_GROUP_SCHED
206 #ifdef CONFIG_SMP
207 SEQ_printf(m, " .%-30s: %Ld.%06ld\n", "load_avg",
208 SPLIT_NS(cfs_rq->load_avg));
209 SEQ_printf(m, " .%-30s: %Ld.%06ld\n", "load_period",
210 SPLIT_NS(cfs_rq->load_period));
211 SEQ_printf(m, " .%-30s: %ld\n", "load_contrib",
212 cfs_rq->load_contribution);
213 SEQ_printf(m, " .%-30s: %d\n", "load_tg",
214 atomic_read(&cfs_rq->tg->load_weight));
215 #endif
216
217 print_cfs_group_stats(m, cpu, cfs_rq->tg);
218 #endif
219 }
220
print_rt_rq(struct seq_file * m,int cpu,struct rt_rq * rt_rq)221 void print_rt_rq(struct seq_file *m, int cpu, struct rt_rq *rt_rq)
222 {
223 #ifdef CONFIG_RT_GROUP_SCHED
224 SEQ_printf(m, "\nrt_rq[%d]:%s\n", cpu, task_group_path(rt_rq->tg));
225 #else
226 SEQ_printf(m, "\nrt_rq[%d]:\n", cpu);
227 #endif
228
229 #define P(x) \
230 SEQ_printf(m, " .%-30s: %Ld\n", #x, (long long)(rt_rq->x))
231 #define PN(x) \
232 SEQ_printf(m, " .%-30s: %Ld.%06ld\n", #x, SPLIT_NS(rt_rq->x))
233
234 P(rt_nr_running);
235 P(rt_throttled);
236 PN(rt_time);
237 PN(rt_runtime);
238
239 #undef PN
240 #undef P
241 }
242
243 extern __read_mostly int sched_clock_running;
244
print_cpu(struct seq_file * m,int cpu)245 static void print_cpu(struct seq_file *m, int cpu)
246 {
247 struct rq *rq = cpu_rq(cpu);
248 unsigned long flags;
249
250 #ifdef CONFIG_X86
251 {
252 unsigned int freq = cpu_khz ? : 1;
253
254 SEQ_printf(m, "\ncpu#%d, %u.%03u MHz\n",
255 cpu, freq / 1000, (freq % 1000));
256 }
257 #else
258 SEQ_printf(m, "\ncpu#%d\n", cpu);
259 #endif
260
261 #define P(x) \
262 SEQ_printf(m, " .%-30s: %Ld\n", #x, (long long)(rq->x))
263 #define PN(x) \
264 SEQ_printf(m, " .%-30s: %Ld.%06ld\n", #x, SPLIT_NS(rq->x))
265
266 P(nr_running);
267 SEQ_printf(m, " .%-30s: %lu\n", "load",
268 rq->load.weight);
269 P(nr_switches);
270 P(nr_load_updates);
271 P(nr_uninterruptible);
272 PN(next_balance);
273 P(curr->pid);
274 PN(clock);
275 P(cpu_load[0]);
276 P(cpu_load[1]);
277 P(cpu_load[2]);
278 P(cpu_load[3]);
279 P(cpu_load[4]);
280 #undef P
281 #undef PN
282
283 #ifdef CONFIG_SCHEDSTATS
284 #define P(n) SEQ_printf(m, " .%-30s: %d\n", #n, rq->n);
285 #define P64(n) SEQ_printf(m, " .%-30s: %Ld\n", #n, rq->n);
286
287 P(yld_count);
288
289 P(sched_switch);
290 P(sched_count);
291 P(sched_goidle);
292 #ifdef CONFIG_SMP
293 P64(avg_idle);
294 #endif
295
296 P(ttwu_count);
297 P(ttwu_local);
298
299 SEQ_printf(m, " .%-30s: %d\n", "bkl_count",
300 rq->rq_sched_info.bkl_count);
301
302 #undef P
303 #undef P64
304 #endif
305 spin_lock_irqsave(&sched_debug_lock, flags);
306 print_cfs_stats(m, cpu);
307 print_rt_stats(m, cpu);
308
309 rcu_read_lock();
310 print_rq(m, rq, cpu);
311 rcu_read_unlock();
312 spin_unlock_irqrestore(&sched_debug_lock, flags);
313 }
314
315 static const char *sched_tunable_scaling_names[] = {
316 "none",
317 "logaritmic",
318 "linear"
319 };
320
sched_debug_show(struct seq_file * m,void * v)321 static int sched_debug_show(struct seq_file *m, void *v)
322 {
323 u64 ktime, sched_clk, cpu_clk;
324 unsigned long flags;
325 int cpu;
326
327 local_irq_save(flags);
328 ktime = ktime_to_ns(ktime_get());
329 sched_clk = sched_clock();
330 cpu_clk = local_clock();
331 local_irq_restore(flags);
332
333 SEQ_printf(m, "Sched Debug Version: v0.10, %s %.*s\n",
334 init_utsname()->release,
335 (int)strcspn(init_utsname()->version, " "),
336 init_utsname()->version);
337
338 #define P(x) \
339 SEQ_printf(m, "%-40s: %Ld\n", #x, (long long)(x))
340 #define PN(x) \
341 SEQ_printf(m, "%-40s: %Ld.%06ld\n", #x, SPLIT_NS(x))
342 PN(ktime);
343 PN(sched_clk);
344 PN(cpu_clk);
345 P(jiffies);
346 #ifdef CONFIG_HAVE_UNSTABLE_SCHED_CLOCK
347 P(sched_clock_stable);
348 #endif
349 #undef PN
350 #undef P
351
352 SEQ_printf(m, "\n");
353 SEQ_printf(m, "sysctl_sched\n");
354
355 #define P(x) \
356 SEQ_printf(m, " .%-40s: %Ld\n", #x, (long long)(x))
357 #define PN(x) \
358 SEQ_printf(m, " .%-40s: %Ld.%06ld\n", #x, SPLIT_NS(x))
359 PN(sysctl_sched_latency);
360 PN(sysctl_sched_min_granularity);
361 PN(sysctl_sched_wakeup_granularity);
362 P(sysctl_sched_child_runs_first);
363 P(sysctl_sched_features);
364 #undef PN
365 #undef P
366
367 SEQ_printf(m, " .%-40s: %d (%s)\n", "sysctl_sched_tunable_scaling",
368 sysctl_sched_tunable_scaling,
369 sched_tunable_scaling_names[sysctl_sched_tunable_scaling]);
370
371 for_each_online_cpu(cpu)
372 print_cpu(m, cpu);
373
374 SEQ_printf(m, "\n");
375
376 return 0;
377 }
378
sysrq_sched_debug_show(void)379 static void sysrq_sched_debug_show(void)
380 {
381 sched_debug_show(NULL, NULL);
382 }
383
sched_debug_open(struct inode * inode,struct file * filp)384 static int sched_debug_open(struct inode *inode, struct file *filp)
385 {
386 return single_open(filp, sched_debug_show, NULL);
387 }
388
389 static const struct file_operations sched_debug_fops = {
390 .open = sched_debug_open,
391 .read = seq_read,
392 .llseek = seq_lseek,
393 .release = single_release,
394 };
395
init_sched_debug_procfs(void)396 static int __init init_sched_debug_procfs(void)
397 {
398 struct proc_dir_entry *pe;
399
400 pe = proc_create("sched_debug", 0444, NULL, &sched_debug_fops);
401 if (!pe)
402 return -ENOMEM;
403 return 0;
404 }
405
406 __initcall(init_sched_debug_procfs);
407
proc_sched_show_task(struct task_struct * p,struct seq_file * m)408 void proc_sched_show_task(struct task_struct *p, struct seq_file *m)
409 {
410 unsigned long nr_switches;
411
412 SEQ_printf(m, "%s (%d, #threads: %d)\n", p->comm, p->pid,
413 get_nr_threads(p));
414 SEQ_printf(m,
415 "---------------------------------------------------------\n");
416 #define __P(F) \
417 SEQ_printf(m, "%-35s:%21Ld\n", #F, (long long)F)
418 #define P(F) \
419 SEQ_printf(m, "%-35s:%21Ld\n", #F, (long long)p->F)
420 #define __PN(F) \
421 SEQ_printf(m, "%-35s:%14Ld.%06ld\n", #F, SPLIT_NS((long long)F))
422 #define PN(F) \
423 SEQ_printf(m, "%-35s:%14Ld.%06ld\n", #F, SPLIT_NS((long long)p->F))
424
425 PN(se.exec_start);
426 PN(se.vruntime);
427 PN(se.sum_exec_runtime);
428
429 nr_switches = p->nvcsw + p->nivcsw;
430
431 #ifdef CONFIG_SCHEDSTATS
432 PN(se.statistics.wait_start);
433 PN(se.statistics.sleep_start);
434 PN(se.statistics.block_start);
435 PN(se.statistics.sleep_max);
436 PN(se.statistics.block_max);
437 PN(se.statistics.exec_max);
438 PN(se.statistics.slice_max);
439 PN(se.statistics.wait_max);
440 PN(se.statistics.wait_sum);
441 P(se.statistics.wait_count);
442 PN(se.statistics.iowait_sum);
443 P(se.statistics.iowait_count);
444 P(sched_info.bkl_count);
445 P(se.nr_migrations);
446 P(se.statistics.nr_migrations_cold);
447 P(se.statistics.nr_failed_migrations_affine);
448 P(se.statistics.nr_failed_migrations_running);
449 P(se.statistics.nr_failed_migrations_hot);
450 P(se.statistics.nr_forced_migrations);
451 P(se.statistics.nr_wakeups);
452 P(se.statistics.nr_wakeups_sync);
453 P(se.statistics.nr_wakeups_migrate);
454 P(se.statistics.nr_wakeups_local);
455 P(se.statistics.nr_wakeups_remote);
456 P(se.statistics.nr_wakeups_affine);
457 P(se.statistics.nr_wakeups_affine_attempts);
458 P(se.statistics.nr_wakeups_passive);
459 P(se.statistics.nr_wakeups_idle);
460
461 {
462 u64 avg_atom, avg_per_cpu;
463
464 avg_atom = p->se.sum_exec_runtime;
465 if (nr_switches)
466 do_div(avg_atom, nr_switches);
467 else
468 avg_atom = -1LL;
469
470 avg_per_cpu = p->se.sum_exec_runtime;
471 if (p->se.nr_migrations) {
472 avg_per_cpu = div64_u64(avg_per_cpu,
473 p->se.nr_migrations);
474 } else {
475 avg_per_cpu = -1LL;
476 }
477
478 __PN(avg_atom);
479 __PN(avg_per_cpu);
480 }
481 #endif
482 __P(nr_switches);
483 SEQ_printf(m, "%-35s:%21Ld\n",
484 "nr_voluntary_switches", (long long)p->nvcsw);
485 SEQ_printf(m, "%-35s:%21Ld\n",
486 "nr_involuntary_switches", (long long)p->nivcsw);
487
488 P(se.load.weight);
489 P(policy);
490 P(prio);
491 #undef PN
492 #undef __PN
493 #undef P
494 #undef __P
495
496 {
497 unsigned int this_cpu = raw_smp_processor_id();
498 u64 t0, t1;
499
500 t0 = cpu_clock(this_cpu);
501 t1 = cpu_clock(this_cpu);
502 SEQ_printf(m, "%-35s:%21Ld\n",
503 "clock-delta", (long long)(t1-t0));
504 }
505 }
506
proc_sched_set_task(struct task_struct * p)507 void proc_sched_set_task(struct task_struct *p)
508 {
509 #ifdef CONFIG_SCHEDSTATS
510 memset(&p->se.statistics, 0, sizeof(p->se.statistics));
511 #endif
512 }
513