Root/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 */
34static 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
46static 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
57static 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->statistics.wait_start);
74    PN(se->statistics.sleep_start);
75    PN(se->statistics.block_start);
76    PN(se->statistics.sleep_max);
77    PN(se->statistics.block_max);
78    PN(se->statistics.exec_max);
79    PN(se->statistics.slice_max);
80    PN(se->statistics.wait_max);
81    PN(se->statistics.wait_sum);
82    P(se->statistics.wait_count);
83#endif
84    P(se->load.weight);
85#undef PN
86#undef P
87}
88#endif
89
90static void
91print_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.statistics.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        rcu_read_lock();
118        cgroup_path(task_group(p)->css.cgroup, path, sizeof(path));
119        rcu_read_unlock();
120        SEQ_printf(m, " %s", path);
121    }
122#endif
123    SEQ_printf(m, "\n");
124}
125
126static void print_rq(struct seq_file *m, struct rq *rq, int rq_cpu)
127{
128    struct task_struct *g, *p;
129    unsigned long flags;
130
131    SEQ_printf(m,
132    "\nrunnable tasks:\n"
133    " task PID tree-key switches prio"
134    " exec-runtime sum-exec sum-sleep\n"
135    "------------------------------------------------------"
136    "----------------------------------------------------\n");
137
138    read_lock_irqsave(&tasklist_lock, flags);
139
140    do_each_thread(g, p) {
141        if (!p->se.on_rq || task_cpu(p) != rq_cpu)
142            continue;
143
144        print_task(m, rq, p);
145    } while_each_thread(g, p);
146
147    read_unlock_irqrestore(&tasklist_lock, flags);
148}
149
150#if defined(CONFIG_CGROUP_SCHED) && \
151    (defined(CONFIG_FAIR_GROUP_SCHED) || defined(CONFIG_RT_GROUP_SCHED))
152static void task_group_path(struct task_group *tg, char *buf, int buflen)
153{
154    /* may be NULL if the underlying cgroup isn't fully-created yet */
155    if (!tg->css.cgroup) {
156        buf[0] = '\0';
157        return;
158    }
159    cgroup_path(tg->css.cgroup, buf, buflen);
160}
161#endif
162
163void print_cfs_rq(struct seq_file *m, int cpu, struct cfs_rq *cfs_rq)
164{
165    s64 MIN_vruntime = -1, min_vruntime, max_vruntime = -1,
166        spread, rq0_min_vruntime, spread0;
167    struct rq *rq = cpu_rq(cpu);
168    struct sched_entity *last;
169    unsigned long flags;
170
171#if defined(CONFIG_CGROUP_SCHED) && defined(CONFIG_FAIR_GROUP_SCHED)
172    char path[128];
173    struct task_group *tg = cfs_rq->tg;
174
175    task_group_path(tg, path, sizeof(path));
176
177    SEQ_printf(m, "\ncfs_rq[%d]:%s\n", cpu, path);
178#else
179    SEQ_printf(m, "\ncfs_rq[%d]:\n", cpu);
180#endif
181    SEQ_printf(m, " .%-30s: %Ld.%06ld\n", "exec_clock",
182            SPLIT_NS(cfs_rq->exec_clock));
183
184    raw_spin_lock_irqsave(&rq->lock, flags);
185    if (cfs_rq->rb_leftmost)
186        MIN_vruntime = (__pick_next_entity(cfs_rq))->vruntime;
187    last = __pick_last_entity(cfs_rq);
188    if (last)
189        max_vruntime = last->vruntime;
190    min_vruntime = cfs_rq->min_vruntime;
191    rq0_min_vruntime = cpu_rq(0)->cfs.min_vruntime;
192    raw_spin_unlock_irqrestore(&rq->lock, flags);
193    SEQ_printf(m, " .%-30s: %Ld.%06ld\n", "MIN_vruntime",
194            SPLIT_NS(MIN_vruntime));
195    SEQ_printf(m, " .%-30s: %Ld.%06ld\n", "min_vruntime",
196            SPLIT_NS(min_vruntime));
197    SEQ_printf(m, " .%-30s: %Ld.%06ld\n", "max_vruntime",
198            SPLIT_NS(max_vruntime));
199    spread = max_vruntime - MIN_vruntime;
200    SEQ_printf(m, " .%-30s: %Ld.%06ld\n", "spread",
201            SPLIT_NS(spread));
202    spread0 = min_vruntime - rq0_min_vruntime;
203    SEQ_printf(m, " .%-30s: %Ld.%06ld\n", "spread0",
204            SPLIT_NS(spread0));
205    SEQ_printf(m, " .%-30s: %ld\n", "nr_running", cfs_rq->nr_running);
206    SEQ_printf(m, " .%-30s: %ld\n", "load", cfs_rq->load.weight);
207
208    SEQ_printf(m, " .%-30s: %d\n", "nr_spread_over",
209            cfs_rq->nr_spread_over);
210#ifdef CONFIG_FAIR_GROUP_SCHED
211#ifdef CONFIG_SMP
212    SEQ_printf(m, " .%-30s: %lu\n", "shares", cfs_rq->shares);
213#endif
214    print_cfs_group_stats(m, cpu, cfs_rq->tg);
215#endif
216}
217
218void print_rt_rq(struct seq_file *m, int cpu, struct rt_rq *rt_rq)
219{
220#if defined(CONFIG_CGROUP_SCHED) && defined(CONFIG_RT_GROUP_SCHED)
221    char path[128];
222    struct task_group *tg = rt_rq->tg;
223
224    task_group_path(tg, path, sizeof(path));
225
226    SEQ_printf(m, "\nrt_rq[%d]:%s\n", cpu, path);
227#else
228    SEQ_printf(m, "\nrt_rq[%d]:\n", cpu);
229#endif
230
231
232#define P(x) \
233    SEQ_printf(m, " .%-30s: %Ld\n", #x, (long long)(rt_rq->x))
234#define PN(x) \
235    SEQ_printf(m, " .%-30s: %Ld.%06ld\n", #x, SPLIT_NS(rt_rq->x))
236
237    P(rt_nr_running);
238    P(rt_throttled);
239    PN(rt_time);
240    PN(rt_runtime);
241
242#undef PN
243#undef P
244}
245
246static void print_cpu(struct seq_file *m, int cpu)
247{
248    struct rq *rq = cpu_rq(cpu);
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    P(bkl_count);
300
301#undef P
302#endif
303    print_cfs_stats(m, cpu);
304    print_rt_stats(m, cpu);
305
306    print_rq(m, rq, cpu);
307}
308
309static const char *sched_tunable_scaling_names[] = {
310    "none",
311    "logaritmic",
312    "linear"
313};
314
315static int sched_debug_show(struct seq_file *m, void *v)
316{
317    u64 now = ktime_to_ns(ktime_get());
318    int cpu;
319
320    SEQ_printf(m, "Sched Debug Version: v0.09, %s %.*s\n",
321        init_utsname()->release,
322        (int)strcspn(init_utsname()->version, " "),
323        init_utsname()->version);
324
325    SEQ_printf(m, "now at %Lu.%06ld msecs\n", SPLIT_NS(now));
326
327#define P(x) \
328    SEQ_printf(m, " .%-40s: %Ld\n", #x, (long long)(x))
329#define PN(x) \
330    SEQ_printf(m, " .%-40s: %Ld.%06ld\n", #x, SPLIT_NS(x))
331    P(jiffies);
332    PN(sysctl_sched_latency);
333    PN(sysctl_sched_min_granularity);
334    PN(sysctl_sched_wakeup_granularity);
335    P(sysctl_sched_child_runs_first);
336    P(sysctl_sched_features);
337#undef PN
338#undef P
339
340    SEQ_printf(m, " .%-40s: %d (%s)\n", "sysctl_sched_tunable_scaling",
341        sysctl_sched_tunable_scaling,
342        sched_tunable_scaling_names[sysctl_sched_tunable_scaling]);
343
344    for_each_online_cpu(cpu)
345        print_cpu(m, cpu);
346
347    SEQ_printf(m, "\n");
348
349    return 0;
350}
351
352static void sysrq_sched_debug_show(void)
353{
354    sched_debug_show(NULL, NULL);
355}
356
357static int sched_debug_open(struct inode *inode, struct file *filp)
358{
359    return single_open(filp, sched_debug_show, NULL);
360}
361
362static const struct file_operations sched_debug_fops = {
363    .open = sched_debug_open,
364    .read = seq_read,
365    .llseek = seq_lseek,
366    .release = single_release,
367};
368
369static int __init init_sched_debug_procfs(void)
370{
371    struct proc_dir_entry *pe;
372
373    pe = proc_create("sched_debug", 0444, NULL, &sched_debug_fops);
374    if (!pe)
375        return -ENOMEM;
376    return 0;
377}
378
379__initcall(init_sched_debug_procfs);
380
381void proc_sched_show_task(struct task_struct *p, struct seq_file *m)
382{
383    unsigned long nr_switches;
384
385    SEQ_printf(m, "%s (%d, #threads: %d)\n", p->comm, p->pid,
386                        get_nr_threads(p));
387    SEQ_printf(m,
388        "---------------------------------------------------------\n");
389#define __P(F) \
390    SEQ_printf(m, "%-35s:%21Ld\n", #F, (long long)F)
391#define P(F) \
392    SEQ_printf(m, "%-35s:%21Ld\n", #F, (long long)p->F)
393#define __PN(F) \
394    SEQ_printf(m, "%-35s:%14Ld.%06ld\n", #F, SPLIT_NS((long long)F))
395#define PN(F) \
396    SEQ_printf(m, "%-35s:%14Ld.%06ld\n", #F, SPLIT_NS((long long)p->F))
397
398    PN(se.exec_start);
399    PN(se.vruntime);
400    PN(se.sum_exec_runtime);
401
402    nr_switches = p->nvcsw + p->nivcsw;
403
404#ifdef CONFIG_SCHEDSTATS
405    PN(se.statistics.wait_start);
406    PN(se.statistics.sleep_start);
407    PN(se.statistics.block_start);
408    PN(se.statistics.sleep_max);
409    PN(se.statistics.block_max);
410    PN(se.statistics.exec_max);
411    PN(se.statistics.slice_max);
412    PN(se.statistics.wait_max);
413    PN(se.statistics.wait_sum);
414    P(se.statistics.wait_count);
415    PN(se.statistics.iowait_sum);
416    P(se.statistics.iowait_count);
417    P(sched_info.bkl_count);
418    P(se.nr_migrations);
419    P(se.statistics.nr_migrations_cold);
420    P(se.statistics.nr_failed_migrations_affine);
421    P(se.statistics.nr_failed_migrations_running);
422    P(se.statistics.nr_failed_migrations_hot);
423    P(se.statistics.nr_forced_migrations);
424    P(se.statistics.nr_wakeups);
425    P(se.statistics.nr_wakeups_sync);
426    P(se.statistics.nr_wakeups_migrate);
427    P(se.statistics.nr_wakeups_local);
428    P(se.statistics.nr_wakeups_remote);
429    P(se.statistics.nr_wakeups_affine);
430    P(se.statistics.nr_wakeups_affine_attempts);
431    P(se.statistics.nr_wakeups_passive);
432    P(se.statistics.nr_wakeups_idle);
433
434    {
435        u64 avg_atom, avg_per_cpu;
436
437        avg_atom = p->se.sum_exec_runtime;
438        if (nr_switches)
439            do_div(avg_atom, nr_switches);
440        else
441            avg_atom = -1LL;
442
443        avg_per_cpu = p->se.sum_exec_runtime;
444        if (p->se.nr_migrations) {
445            avg_per_cpu = div64_u64(avg_per_cpu,
446                        p->se.nr_migrations);
447        } else {
448            avg_per_cpu = -1LL;
449        }
450
451        __PN(avg_atom);
452        __PN(avg_per_cpu);
453    }
454#endif
455    __P(nr_switches);
456    SEQ_printf(m, "%-35s:%21Ld\n",
457           "nr_voluntary_switches", (long long)p->nvcsw);
458    SEQ_printf(m, "%-35s:%21Ld\n",
459           "nr_involuntary_switches", (long long)p->nivcsw);
460
461    P(se.load.weight);
462    P(policy);
463    P(prio);
464#undef PN
465#undef __PN
466#undef P
467#undef __P
468
469    {
470        unsigned int this_cpu = raw_smp_processor_id();
471        u64 t0, t1;
472
473        t0 = cpu_clock(this_cpu);
474        t1 = cpu_clock(this_cpu);
475        SEQ_printf(m, "%-35s:%21Ld\n",
476               "clock-delta", (long long)(t1-t0));
477    }
478}
479
480void proc_sched_set_task(struct task_struct *p)
481{
482#ifdef CONFIG_SCHEDSTATS
483    memset(&p->se.statistics, 0, sizeof(p->se.statistics));
484#endif
485}
486

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