linux/kernel/sched_debug.c
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   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
  19static 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 */
  36static 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
  48static 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
  59static 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
  92static char group_path[PATH_MAX];
  93
  94static 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
 111static void
 112print_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
 140static 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
 164void 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
 221void 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
 243extern __read_mostly int sched_clock_running;
 244
 245static 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
 315static const char *sched_tunable_scaling_names[] = {
 316        "none",
 317        "logaritmic",
 318        "linear"
 319};
 320
 321static 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
 379static void sysrq_sched_debug_show(void)
 380{
 381        sched_debug_show(NULL, NULL);
 382}
 383
 384static int sched_debug_open(struct inode *inode, struct file *filp)
 385{
 386        return single_open(filp, sched_debug_show, NULL);
 387}
 388
 389static 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
 396static 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
 408void 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
 507void 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