FS-Cache: Add the FS-Cache netfs API and documentation
[linux-2.6] / kernel / sched_debug.c
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 /*
20  * This allows printing both to /proc/sched_debug and
21  * to the console
22  */
23 #define SEQ_printf(m, x...)                     \
24  do {                                           \
25         if (m)                                  \
26                 seq_printf(m, x);               \
27         else                                    \
28                 printk(x);                      \
29  } while (0)
30
31 /*
32  * Ease the printing of nsec fields:
33  */
34 static long long nsec_high(unsigned long long nsec)
35 {
36         if ((long long)nsec < 0) {
37                 nsec = -nsec;
38                 do_div(nsec, 1000000);
39                 return -nsec;
40         }
41         do_div(nsec, 1000000);
42
43         return nsec;
44 }
45
46 static unsigned long nsec_low(unsigned long long nsec)
47 {
48         if ((long long)nsec < 0)
49                 nsec = -nsec;
50
51         return do_div(nsec, 1000000);
52 }
53
54 #define SPLIT_NS(x) nsec_high(x), nsec_low(x)
55
56 #ifdef CONFIG_FAIR_GROUP_SCHED
57 static void print_cfs_group_stats(struct seq_file *m, int cpu,
58                 struct task_group *tg)
59 {
60         struct sched_entity *se = tg->se[cpu];
61         if (!se)
62                 return;
63
64 #define P(F) \
65         SEQ_printf(m, "  .%-30s: %lld\n", #F, (long long)F)
66 #define PN(F) \
67         SEQ_printf(m, "  .%-30s: %lld.%06ld\n", #F, SPLIT_NS((long long)F))
68
69         PN(se->exec_start);
70         PN(se->vruntime);
71         PN(se->sum_exec_runtime);
72 #ifdef CONFIG_SCHEDSTATS
73         PN(se->wait_start);
74         PN(se->sleep_start);
75         PN(se->block_start);
76         PN(se->sleep_max);
77         PN(se->block_max);
78         PN(se->exec_max);
79         PN(se->slice_max);
80         PN(se->wait_max);
81         PN(se->wait_sum);
82         P(se->wait_count);
83 #endif
84         P(se->load.weight);
85 #undef PN
86 #undef P
87 }
88 #endif
89
90 static void
91 print_task(struct seq_file *m, struct rq *rq, struct task_struct *p)
92 {
93         if (rq->curr == p)
94                 SEQ_printf(m, "R");
95         else
96                 SEQ_printf(m, " ");
97
98         SEQ_printf(m, "%15s %5d %9Ld.%06ld %9Ld %5d ",
99                 p->comm, p->pid,
100                 SPLIT_NS(p->se.vruntime),
101                 (long long)(p->nvcsw + p->nivcsw),
102                 p->prio);
103 #ifdef CONFIG_SCHEDSTATS
104         SEQ_printf(m, "%9Ld.%06ld %9Ld.%06ld %9Ld.%06ld",
105                 SPLIT_NS(p->se.vruntime),
106                 SPLIT_NS(p->se.sum_exec_runtime),
107                 SPLIT_NS(p->se.sum_sleep_runtime));
108 #else
109         SEQ_printf(m, "%15Ld %15Ld %15Ld.%06ld %15Ld.%06ld %15Ld.%06ld",
110                 0LL, 0LL, 0LL, 0L, 0LL, 0L, 0LL, 0L);
111 #endif
112
113 #ifdef CONFIG_CGROUP_SCHED
114         {
115                 char path[64];
116
117                 cgroup_path(task_group(p)->css.cgroup, path, sizeof(path));
118                 SEQ_printf(m, " %s", path);
119         }
120 #endif
121         SEQ_printf(m, "\n");
122 }
123
124 static void print_rq(struct seq_file *m, struct rq *rq, int rq_cpu)
125 {
126         struct task_struct *g, *p;
127         unsigned long flags;
128
129         SEQ_printf(m,
130         "\nrunnable tasks:\n"
131         "            task   PID         tree-key  switches  prio"
132         "     exec-runtime         sum-exec        sum-sleep\n"
133         "------------------------------------------------------"
134         "----------------------------------------------------\n");
135
136         read_lock_irqsave(&tasklist_lock, flags);
137
138         do_each_thread(g, p) {
139                 if (!p->se.on_rq || task_cpu(p) != rq_cpu)
140                         continue;
141
142                 print_task(m, rq, p);
143         } while_each_thread(g, p);
144
145         read_unlock_irqrestore(&tasklist_lock, flags);
146 }
147
148 #if defined(CONFIG_CGROUP_SCHED) && \
149         (defined(CONFIG_FAIR_GROUP_SCHED) || defined(CONFIG_RT_GROUP_SCHED))
150 static void task_group_path(struct task_group *tg, char *buf, int buflen)
151 {
152         /* may be NULL if the underlying cgroup isn't fully-created yet */
153         if (!tg->css.cgroup) {
154                 buf[0] = '\0';
155                 return;
156         }
157         cgroup_path(tg->css.cgroup, buf, buflen);
158 }
159 #endif
160
161 void print_cfs_rq(struct seq_file *m, int cpu, struct cfs_rq *cfs_rq)
162 {
163         s64 MIN_vruntime = -1, min_vruntime, max_vruntime = -1,
164                 spread, rq0_min_vruntime, spread0;
165         struct rq *rq = &per_cpu(runqueues, cpu);
166         struct sched_entity *last;
167         unsigned long flags;
168
169 #if defined(CONFIG_CGROUP_SCHED) && defined(CONFIG_FAIR_GROUP_SCHED)
170         char path[128];
171         struct task_group *tg = cfs_rq->tg;
172
173         task_group_path(tg, path, sizeof(path));
174
175         SEQ_printf(m, "\ncfs_rq[%d]:%s\n", cpu, path);
176 #elif defined(CONFIG_USER_SCHED) && defined(CONFIG_FAIR_GROUP_SCHED)
177         {
178                 uid_t uid = cfs_rq->tg->uid;
179                 SEQ_printf(m, "\ncfs_rq[%d] for UID: %u\n", cpu, uid);
180         }
181 #else
182         SEQ_printf(m, "\ncfs_rq[%d]:\n", cpu);
183 #endif
184         SEQ_printf(m, "  .%-30s: %Ld.%06ld\n", "exec_clock",
185                         SPLIT_NS(cfs_rq->exec_clock));
186
187         spin_lock_irqsave(&rq->lock, flags);
188         if (cfs_rq->rb_leftmost)
189                 MIN_vruntime = (__pick_next_entity(cfs_rq))->vruntime;
190         last = __pick_last_entity(cfs_rq);
191         if (last)
192                 max_vruntime = last->vruntime;
193         min_vruntime = cfs_rq->min_vruntime;
194         rq0_min_vruntime = per_cpu(runqueues, 0).cfs.min_vruntime;
195         spin_unlock_irqrestore(&rq->lock, flags);
196         SEQ_printf(m, "  .%-30s: %Ld.%06ld\n", "MIN_vruntime",
197                         SPLIT_NS(MIN_vruntime));
198         SEQ_printf(m, "  .%-30s: %Ld.%06ld\n", "min_vruntime",
199                         SPLIT_NS(min_vruntime));
200         SEQ_printf(m, "  .%-30s: %Ld.%06ld\n", "max_vruntime",
201                         SPLIT_NS(max_vruntime));
202         spread = max_vruntime - MIN_vruntime;
203         SEQ_printf(m, "  .%-30s: %Ld.%06ld\n", "spread",
204                         SPLIT_NS(spread));
205         spread0 = min_vruntime - rq0_min_vruntime;
206         SEQ_printf(m, "  .%-30s: %Ld.%06ld\n", "spread0",
207                         SPLIT_NS(spread0));
208         SEQ_printf(m, "  .%-30s: %ld\n", "nr_running", cfs_rq->nr_running);
209         SEQ_printf(m, "  .%-30s: %ld\n", "load", cfs_rq->load.weight);
210
211         SEQ_printf(m, "  .%-30s: %d\n", "nr_spread_over",
212                         cfs_rq->nr_spread_over);
213 #ifdef CONFIG_FAIR_GROUP_SCHED
214 #ifdef CONFIG_SMP
215         SEQ_printf(m, "  .%-30s: %lu\n", "shares", cfs_rq->shares);
216 #endif
217         print_cfs_group_stats(m, cpu, cfs_rq->tg);
218 #endif
219 }
220
221 void print_rt_rq(struct seq_file *m, int cpu, struct rt_rq *rt_rq)
222 {
223 #if defined(CONFIG_CGROUP_SCHED) && defined(CONFIG_RT_GROUP_SCHED)
224         char path[128];
225         struct task_group *tg = rt_rq->tg;
226
227         task_group_path(tg, path, sizeof(path));
228
229         SEQ_printf(m, "\nrt_rq[%d]:%s\n", cpu, path);
230 #else
231         SEQ_printf(m, "\nrt_rq[%d]:\n", cpu);
232 #endif
233
234
235 #define P(x) \
236         SEQ_printf(m, "  .%-30s: %Ld\n", #x, (long long)(rt_rq->x))
237 #define PN(x) \
238         SEQ_printf(m, "  .%-30s: %Ld.%06ld\n", #x, SPLIT_NS(rt_rq->x))
239
240         P(rt_nr_running);
241         P(rt_throttled);
242         PN(rt_time);
243         PN(rt_runtime);
244
245 #undef PN
246 #undef P
247 }
248
249 static void print_cpu(struct seq_file *m, int cpu)
250 {
251         struct rq *rq = &per_cpu(runqueues, cpu);
252
253 #ifdef CONFIG_X86
254         {
255                 unsigned int freq = cpu_khz ? : 1;
256
257                 SEQ_printf(m, "\ncpu#%d, %u.%03u MHz\n",
258                            cpu, freq / 1000, (freq % 1000));
259         }
260 #else
261         SEQ_printf(m, "\ncpu#%d\n", cpu);
262 #endif
263
264 #define P(x) \
265         SEQ_printf(m, "  .%-30s: %Ld\n", #x, (long long)(rq->x))
266 #define PN(x) \
267         SEQ_printf(m, "  .%-30s: %Ld.%06ld\n", #x, SPLIT_NS(rq->x))
268
269         P(nr_running);
270         SEQ_printf(m, "  .%-30s: %lu\n", "load",
271                    rq->load.weight);
272         P(nr_switches);
273         P(nr_load_updates);
274         P(nr_uninterruptible);
275         PN(next_balance);
276         P(curr->pid);
277         PN(clock);
278         P(cpu_load[0]);
279         P(cpu_load[1]);
280         P(cpu_load[2]);
281         P(cpu_load[3]);
282         P(cpu_load[4]);
283 #undef P
284 #undef PN
285
286 #ifdef CONFIG_SCHEDSTATS
287 #define P(n) SEQ_printf(m, "  .%-30s: %d\n", #n, rq->n);
288
289         P(yld_count);
290
291         P(sched_switch);
292         P(sched_count);
293         P(sched_goidle);
294
295         P(ttwu_count);
296         P(ttwu_local);
297
298         P(bkl_count);
299
300 #undef P
301 #endif
302         print_cfs_stats(m, cpu);
303         print_rt_stats(m, cpu);
304
305         print_rq(m, rq, cpu);
306 }
307
308 static int sched_debug_show(struct seq_file *m, void *v)
309 {
310         u64 now = ktime_to_ns(ktime_get());
311         int cpu;
312
313         SEQ_printf(m, "Sched Debug Version: v0.09, %s %.*s\n",
314                 init_utsname()->release,
315                 (int)strcspn(init_utsname()->version, " "),
316                 init_utsname()->version);
317
318         SEQ_printf(m, "now at %Lu.%06ld msecs\n", SPLIT_NS(now));
319
320 #define P(x) \
321         SEQ_printf(m, "  .%-40s: %Ld\n", #x, (long long)(x))
322 #define PN(x) \
323         SEQ_printf(m, "  .%-40s: %Ld.%06ld\n", #x, SPLIT_NS(x))
324         P(jiffies);
325         PN(sysctl_sched_latency);
326         PN(sysctl_sched_min_granularity);
327         PN(sysctl_sched_wakeup_granularity);
328         PN(sysctl_sched_child_runs_first);
329         P(sysctl_sched_features);
330 #undef PN
331 #undef P
332
333         for_each_online_cpu(cpu)
334                 print_cpu(m, cpu);
335
336         SEQ_printf(m, "\n");
337
338         return 0;
339 }
340
341 static void sysrq_sched_debug_show(void)
342 {
343         sched_debug_show(NULL, NULL);
344 }
345
346 static int sched_debug_open(struct inode *inode, struct file *filp)
347 {
348         return single_open(filp, sched_debug_show, NULL);
349 }
350
351 static const struct file_operations sched_debug_fops = {
352         .open           = sched_debug_open,
353         .read           = seq_read,
354         .llseek         = seq_lseek,
355         .release        = single_release,
356 };
357
358 static int __init init_sched_debug_procfs(void)
359 {
360         struct proc_dir_entry *pe;
361
362         pe = proc_create("sched_debug", 0444, NULL, &sched_debug_fops);
363         if (!pe)
364                 return -ENOMEM;
365         return 0;
366 }
367
368 __initcall(init_sched_debug_procfs);
369
370 void proc_sched_show_task(struct task_struct *p, struct seq_file *m)
371 {
372         unsigned long nr_switches;
373         unsigned long flags;
374         int num_threads = 1;
375
376         if (lock_task_sighand(p, &flags)) {
377                 num_threads = atomic_read(&p->signal->count);
378                 unlock_task_sighand(p, &flags);
379         }
380
381         SEQ_printf(m, "%s (%d, #threads: %d)\n", p->comm, p->pid, num_threads);
382         SEQ_printf(m,
383                 "---------------------------------------------------------\n");
384 #define __P(F) \
385         SEQ_printf(m, "%-35s:%21Ld\n", #F, (long long)F)
386 #define P(F) \
387         SEQ_printf(m, "%-35s:%21Ld\n", #F, (long long)p->F)
388 #define __PN(F) \
389         SEQ_printf(m, "%-35s:%14Ld.%06ld\n", #F, SPLIT_NS((long long)F))
390 #define PN(F) \
391         SEQ_printf(m, "%-35s:%14Ld.%06ld\n", #F, SPLIT_NS((long long)p->F))
392
393         PN(se.exec_start);
394         PN(se.vruntime);
395         PN(se.sum_exec_runtime);
396         PN(se.avg_overlap);
397         PN(se.avg_wakeup);
398
399         nr_switches = p->nvcsw + p->nivcsw;
400
401 #ifdef CONFIG_SCHEDSTATS
402         PN(se.wait_start);
403         PN(se.sleep_start);
404         PN(se.block_start);
405         PN(se.sleep_max);
406         PN(se.block_max);
407         PN(se.exec_max);
408         PN(se.slice_max);
409         PN(se.wait_max);
410         PN(se.wait_sum);
411         P(se.wait_count);
412         P(sched_info.bkl_count);
413         P(se.nr_migrations);
414         P(se.nr_migrations_cold);
415         P(se.nr_failed_migrations_affine);
416         P(se.nr_failed_migrations_running);
417         P(se.nr_failed_migrations_hot);
418         P(se.nr_forced_migrations);
419         P(se.nr_forced2_migrations);
420         P(se.nr_wakeups);
421         P(se.nr_wakeups_sync);
422         P(se.nr_wakeups_migrate);
423         P(se.nr_wakeups_local);
424         P(se.nr_wakeups_remote);
425         P(se.nr_wakeups_affine);
426         P(se.nr_wakeups_affine_attempts);
427         P(se.nr_wakeups_passive);
428         P(se.nr_wakeups_idle);
429
430         {
431                 u64 avg_atom, avg_per_cpu;
432
433                 avg_atom = p->se.sum_exec_runtime;
434                 if (nr_switches)
435                         do_div(avg_atom, nr_switches);
436                 else
437                         avg_atom = -1LL;
438
439                 avg_per_cpu = p->se.sum_exec_runtime;
440                 if (p->se.nr_migrations) {
441                         avg_per_cpu = div64_u64(avg_per_cpu,
442                                                 p->se.nr_migrations);
443                 } else {
444                         avg_per_cpu = -1LL;
445                 }
446
447                 __PN(avg_atom);
448                 __PN(avg_per_cpu);
449         }
450 #endif
451         __P(nr_switches);
452         SEQ_printf(m, "%-35s:%21Ld\n",
453                    "nr_voluntary_switches", (long long)p->nvcsw);
454         SEQ_printf(m, "%-35s:%21Ld\n",
455                    "nr_involuntary_switches", (long long)p->nivcsw);
456
457         P(se.load.weight);
458         P(policy);
459         P(prio);
460 #undef PN
461 #undef __PN
462 #undef P
463 #undef __P
464
465         {
466                 unsigned int this_cpu = raw_smp_processor_id();
467                 u64 t0, t1;
468
469                 t0 = cpu_clock(this_cpu);
470                 t1 = cpu_clock(this_cpu);
471                 SEQ_printf(m, "%-35s:%21Ld\n",
472                            "clock-delta", (long long)(t1-t0));
473         }
474 }
475
476 void proc_sched_set_task(struct task_struct *p)
477 {
478 #ifdef CONFIG_SCHEDSTATS
479         p->se.wait_max                          = 0;
480         p->se.wait_sum                          = 0;
481         p->se.wait_count                        = 0;
482         p->se.sleep_max                         = 0;
483         p->se.sum_sleep_runtime                 = 0;
484         p->se.block_max                         = 0;
485         p->se.exec_max                          = 0;
486         p->se.slice_max                         = 0;
487         p->se.nr_migrations                     = 0;
488         p->se.nr_migrations_cold                = 0;
489         p->se.nr_failed_migrations_affine       = 0;
490         p->se.nr_failed_migrations_running      = 0;
491         p->se.nr_failed_migrations_hot          = 0;
492         p->se.nr_forced_migrations              = 0;
493         p->se.nr_forced2_migrations             = 0;
494         p->se.nr_wakeups                        = 0;
495         p->se.nr_wakeups_sync                   = 0;
496         p->se.nr_wakeups_migrate                = 0;
497         p->se.nr_wakeups_local                  = 0;
498         p->se.nr_wakeups_remote                 = 0;
499         p->se.nr_wakeups_affine                 = 0;
500         p->se.nr_wakeups_affine_attempts        = 0;
501         p->se.nr_wakeups_passive                = 0;
502         p->se.nr_wakeups_idle                   = 0;
503         p->sched_info.bkl_count                 = 0;
504 #endif
505         p->se.sum_exec_runtime                  = 0;
506         p->se.prev_sum_exec_runtime             = 0;
507         p->nvcsw                                = 0;
508         p->nivcsw                               = 0;
509 }