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
  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
  56static void
  57print_task(struct seq_file *m, struct rq *rq, struct task_struct *p)
  58{
  59        if (rq->curr == p)
  60                SEQ_printf(m, "R");
  61        else
  62                SEQ_printf(m, " ");
  63
  64        SEQ_printf(m, "%15s %5d %9Ld.%06ld %9Ld %5d ",
  65                p->comm, p->pid,
  66                SPLIT_NS(p->se.vruntime),
  67                (long long)(p->nvcsw + p->nivcsw),
  68                p->prio);
  69#ifdef CONFIG_SCHEDSTATS
  70        SEQ_printf(m, "%9Ld.%06ld %9Ld.%06ld %9Ld.%06ld",
  71                SPLIT_NS(p->se.vruntime),
  72                SPLIT_NS(p->se.sum_exec_runtime),
  73                SPLIT_NS(p->se.sum_sleep_runtime));
  74#else
  75        SEQ_printf(m, "%15Ld %15Ld %15Ld.%06ld %15Ld.%06ld %15Ld.%06ld",
  76                0LL, 0LL, 0LL, 0L, 0LL, 0L, 0LL, 0L);
  77#endif
  78
  79#ifdef CONFIG_CGROUP_SCHED
  80        {
  81                char path[64];
  82
  83                cgroup_path(task_group(p)->css.cgroup, path, sizeof(path));
  84                SEQ_printf(m, " %s", path);
  85        }
  86#endif
  87        SEQ_printf(m, "\n");
  88}
  89
  90static void print_rq(struct seq_file *m, struct rq *rq, int rq_cpu)
  91{
  92        struct task_struct *g, *p;
  93        unsigned long flags;
  94
  95        SEQ_printf(m,
  96        "\nrunnable tasks:\n"
  97        "            task   PID         tree-key  switches  prio"
  98        "     exec-runtime         sum-exec        sum-sleep\n"
  99        "------------------------------------------------------"
 100        "----------------------------------------------------\n");
 101
 102        read_lock_irqsave(&tasklist_lock, flags);
 103
 104        do_each_thread(g, p) {
 105                if (!p->se.on_rq || task_cpu(p) != rq_cpu)
 106                        continue;
 107
 108                print_task(m, rq, p);
 109        } while_each_thread(g, p);
 110
 111        read_unlock_irqrestore(&tasklist_lock, flags);
 112}
 113
 114void print_cfs_rq(struct seq_file *m, int cpu, struct cfs_rq *cfs_rq)
 115{
 116        s64 MIN_vruntime = -1, min_vruntime, max_vruntime = -1,
 117                spread, rq0_min_vruntime, spread0;
 118        struct rq *rq = &per_cpu(runqueues, cpu);
 119        struct sched_entity *last;
 120        unsigned long flags;
 121
 122#if defined(CONFIG_CGROUP_SCHED) && defined(CONFIG_FAIR_GROUP_SCHED)
 123        char path[128] = "";
 124        struct cgroup *cgroup = NULL;
 125        struct task_group *tg = cfs_rq->tg;
 126
 127        if (tg)
 128                cgroup = tg->css.cgroup;
 129
 130        if (cgroup)
 131                cgroup_path(cgroup, path, sizeof(path));
 132
 133        SEQ_printf(m, "\ncfs_rq[%d]:%s\n", cpu, path);
 134#else
 135        SEQ_printf(m, "\ncfs_rq[%d]:\n", cpu);
 136#endif
 137
 138        SEQ_printf(m, "  .%-30s: %Ld.%06ld\n", "exec_clock",
 139                        SPLIT_NS(cfs_rq->exec_clock));
 140
 141        spin_lock_irqsave(&rq->lock, flags);
 142        if (cfs_rq->rb_leftmost)
 143                MIN_vruntime = (__pick_next_entity(cfs_rq))->vruntime;
 144        last = __pick_last_entity(cfs_rq);
 145        if (last)
 146                max_vruntime = last->vruntime;
 147        min_vruntime = cfs_rq->min_vruntime;
 148        rq0_min_vruntime = per_cpu(runqueues, 0).cfs.min_vruntime;
 149        spin_unlock_irqrestore(&rq->lock, flags);
 150        SEQ_printf(m, "  .%-30s: %Ld.%06ld\n", "MIN_vruntime",
 151                        SPLIT_NS(MIN_vruntime));
 152        SEQ_printf(m, "  .%-30s: %Ld.%06ld\n", "min_vruntime",
 153                        SPLIT_NS(min_vruntime));
 154        SEQ_printf(m, "  .%-30s: %Ld.%06ld\n", "max_vruntime",
 155                        SPLIT_NS(max_vruntime));
 156        spread = max_vruntime - MIN_vruntime;
 157        SEQ_printf(m, "  .%-30s: %Ld.%06ld\n", "spread",
 158                        SPLIT_NS(spread));
 159        spread0 = min_vruntime - rq0_min_vruntime;
 160        SEQ_printf(m, "  .%-30s: %Ld.%06ld\n", "spread0",
 161                        SPLIT_NS(spread0));
 162        SEQ_printf(m, "  .%-30s: %ld\n", "nr_running", cfs_rq->nr_running);
 163        SEQ_printf(m, "  .%-30s: %ld\n", "load", cfs_rq->load.weight);
 164
 165        SEQ_printf(m, "  .%-30s: %d\n", "nr_spread_over",
 166                        cfs_rq->nr_spread_over);
 167#ifdef CONFIG_FAIR_GROUP_SCHED
 168#ifdef CONFIG_SMP
 169        SEQ_printf(m, "  .%-30s: %lu\n", "shares", cfs_rq->shares);
 170#endif
 171#endif
 172}
 173
 174void print_rt_rq(struct seq_file *m, int cpu, struct rt_rq *rt_rq)
 175{
 176#if defined(CONFIG_CGROUP_SCHED) && defined(CONFIG_RT_GROUP_SCHED)
 177        char path[128] = "";
 178        struct cgroup *cgroup = NULL;
 179        struct task_group *tg = rt_rq->tg;
 180
 181        if (tg)
 182                cgroup = tg->css.cgroup;
 183
 184        if (cgroup)
 185                cgroup_path(cgroup, path, sizeof(path));
 186
 187        SEQ_printf(m, "\nrt_rq[%d]:%s\n", cpu, path);
 188#else
 189        SEQ_printf(m, "\nrt_rq[%d]:\n", cpu);
 190#endif
 191
 192
 193#define P(x) \
 194        SEQ_printf(m, "  .%-30s: %Ld\n", #x, (long long)(rt_rq->x))
 195#define PN(x) \
 196        SEQ_printf(m, "  .%-30s: %Ld.%06ld\n", #x, SPLIT_NS(rt_rq->x))
 197
 198        P(rt_nr_running);
 199        P(rt_throttled);
 200        PN(rt_time);
 201        PN(rt_runtime);
 202
 203#undef PN
 204#undef P
 205}
 206
 207static void print_cpu(struct seq_file *m, int cpu)
 208{
 209        struct rq *rq = &per_cpu(runqueues, cpu);
 210
 211#ifdef CONFIG_X86
 212        {
 213                unsigned int freq = cpu_khz ? : 1;
 214
 215                SEQ_printf(m, "\ncpu#%d, %u.%03u MHz\n",
 216                           cpu, freq / 1000, (freq % 1000));
 217        }
 218#else
 219        SEQ_printf(m, "\ncpu#%d\n", cpu);
 220#endif
 221
 222#define P(x) \
 223        SEQ_printf(m, "  .%-30s: %Ld\n", #x, (long long)(rq->x))
 224#define PN(x) \
 225        SEQ_printf(m, "  .%-30s: %Ld.%06ld\n", #x, SPLIT_NS(rq->x))
 226
 227        P(nr_running);
 228        SEQ_printf(m, "  .%-30s: %lu\n", "load",
 229                   rq->load.weight);
 230        P(nr_switches);
 231        P(nr_load_updates);
 232        P(nr_uninterruptible);
 233        SEQ_printf(m, "  .%-30s: %lu\n", "jiffies", jiffies);
 234        PN(next_balance);
 235        P(curr->pid);
 236        PN(clock);
 237        P(cpu_load[0]);
 238        P(cpu_load[1]);
 239        P(cpu_load[2]);
 240        P(cpu_load[3]);
 241        P(cpu_load[4]);
 242#undef P
 243#undef PN
 244
 245#ifdef CONFIG_SCHEDSTATS
 246#define P(n) SEQ_printf(m, "  .%-30s: %d\n", #n, rq->n);
 247
 248        P(yld_exp_empty);
 249        P(yld_act_empty);
 250        P(yld_both_empty);
 251        P(yld_count);
 252
 253        P(sched_switch);
 254        P(sched_count);
 255        P(sched_goidle);
 256
 257        P(ttwu_count);
 258        P(ttwu_local);
 259
 260        P(bkl_count);
 261
 262#undef P
 263#endif
 264        print_cfs_stats(m, cpu);
 265        print_rt_stats(m, cpu);
 266
 267        print_rq(m, rq, cpu);
 268}
 269
 270static int sched_debug_show(struct seq_file *m, void *v)
 271{
 272        u64 now = ktime_to_ns(ktime_get());
 273        int cpu;
 274
 275        SEQ_printf(m, "Sched Debug Version: v0.07, %s %.*s\n",
 276                init_utsname()->release,
 277                (int)strcspn(init_utsname()->version, " "),
 278                init_utsname()->version);
 279
 280        SEQ_printf(m, "now at %Lu.%06ld msecs\n", SPLIT_NS(now));
 281
 282#define P(x) \
 283        SEQ_printf(m, "  .%-40s: %Ld\n", #x, (long long)(x))
 284#define PN(x) \
 285        SEQ_printf(m, "  .%-40s: %Ld.%06ld\n", #x, SPLIT_NS(x))
 286        PN(sysctl_sched_latency);
 287        PN(sysctl_sched_min_granularity);
 288        PN(sysctl_sched_wakeup_granularity);
 289        PN(sysctl_sched_child_runs_first);
 290        P(sysctl_sched_features);
 291#undef PN
 292#undef P
 293
 294        for_each_online_cpu(cpu)
 295                print_cpu(m, cpu);
 296
 297        SEQ_printf(m, "\n");
 298
 299        return 0;
 300}
 301
 302static void sysrq_sched_debug_show(void)
 303{
 304        sched_debug_show(NULL, NULL);
 305}
 306
 307static int sched_debug_open(struct inode *inode, struct file *filp)
 308{
 309        return single_open(filp, sched_debug_show, NULL);
 310}
 311
 312static const struct file_operations sched_debug_fops = {
 313        .open           = sched_debug_open,
 314        .read           = seq_read,
 315        .llseek         = seq_lseek,
 316        .release        = single_release,
 317};
 318
 319static int __init init_sched_debug_procfs(void)
 320{
 321        struct proc_dir_entry *pe;
 322
 323        pe = proc_create("sched_debug", 0444, NULL, &sched_debug_fops);
 324        if (!pe)
 325                return -ENOMEM;
 326        return 0;
 327}
 328
 329__initcall(init_sched_debug_procfs);
 330
 331void proc_sched_show_task(struct task_struct *p, struct seq_file *m)
 332{
 333        unsigned long nr_switches;
 334        unsigned long flags;
 335        int num_threads = 1;
 336
 337        if (lock_task_sighand(p, &flags)) {
 338                num_threads = atomic_read(&p->signal->count);
 339                unlock_task_sighand(p, &flags);
 340        }
 341
 342        SEQ_printf(m, "%s (%d, #threads: %d)\n", p->comm, p->pid, num_threads);
 343        SEQ_printf(m,
 344                "---------------------------------------------------------\n");
 345#define __P(F) \
 346        SEQ_printf(m, "%-35s:%21Ld\n", #F, (long long)F)
 347#define P(F) \
 348        SEQ_printf(m, "%-35s:%21Ld\n", #F, (long long)p->F)
 349#define __PN(F) \
 350        SEQ_printf(m, "%-35s:%14Ld.%06ld\n", #F, SPLIT_NS((long long)F))
 351#define PN(F) \
 352        SEQ_printf(m, "%-35s:%14Ld.%06ld\n", #F, SPLIT_NS((long long)p->F))
 353
 354        PN(se.exec_start);
 355        PN(se.vruntime);
 356        PN(se.sum_exec_runtime);
 357        PN(se.avg_overlap);
 358
 359        nr_switches = p->nvcsw + p->nivcsw;
 360
 361#ifdef CONFIG_SCHEDSTATS
 362        PN(se.wait_start);
 363        PN(se.sleep_start);
 364        PN(se.block_start);
 365        PN(se.sleep_max);
 366        PN(se.block_max);
 367        PN(se.exec_max);
 368        PN(se.slice_max);
 369        PN(se.wait_max);
 370        PN(se.wait_sum);
 371        P(se.wait_count);
 372        P(sched_info.bkl_count);
 373        P(se.nr_migrations);
 374        P(se.nr_migrations_cold);
 375        P(se.nr_failed_migrations_affine);
 376        P(se.nr_failed_migrations_running);
 377        P(se.nr_failed_migrations_hot);
 378        P(se.nr_forced_migrations);
 379        P(se.nr_forced2_migrations);
 380        P(se.nr_wakeups);
 381        P(se.nr_wakeups_sync);
 382        P(se.nr_wakeups_migrate);
 383        P(se.nr_wakeups_local);
 384        P(se.nr_wakeups_remote);
 385        P(se.nr_wakeups_affine);
 386        P(se.nr_wakeups_affine_attempts);
 387        P(se.nr_wakeups_passive);
 388        P(se.nr_wakeups_idle);
 389
 390        {
 391                u64 avg_atom, avg_per_cpu;
 392
 393                avg_atom = p->se.sum_exec_runtime;
 394                if (nr_switches)
 395                        do_div(avg_atom, nr_switches);
 396                else
 397                        avg_atom = -1LL;
 398
 399                avg_per_cpu = p->se.sum_exec_runtime;
 400                if (p->se.nr_migrations) {
 401                        avg_per_cpu = div64_u64(avg_per_cpu,
 402                                                p->se.nr_migrations);
 403                } else {
 404                        avg_per_cpu = -1LL;
 405                }
 406
 407                __PN(avg_atom);
 408                __PN(avg_per_cpu);
 409        }
 410#endif
 411        __P(nr_switches);
 412        SEQ_printf(m, "%-35s:%21Ld\n",
 413                   "nr_voluntary_switches", (long long)p->nvcsw);
 414        SEQ_printf(m, "%-35s:%21Ld\n",
 415                   "nr_involuntary_switches", (long long)p->nivcsw);
 416
 417        P(se.load.weight);
 418        P(policy);
 419        P(prio);
 420#undef PN
 421#undef __PN
 422#undef P
 423#undef __P
 424
 425        {
 426                unsigned int this_cpu = raw_smp_processor_id();
 427                u64 t0, t1;
 428
 429                t0 = cpu_clock(this_cpu);
 430                t1 = cpu_clock(this_cpu);
 431                SEQ_printf(m, "%-35s:%21Ld\n",
 432                           "clock-delta", (long long)(t1-t0));
 433        }
 434}
 435
 436void proc_sched_set_task(struct task_struct *p)
 437{
 438#ifdef CONFIG_SCHEDSTATS
 439        p->se.wait_max                          = 0;
 440        p->se.wait_sum                          = 0;
 441        p->se.wait_count                        = 0;
 442        p->se.sleep_max                         = 0;
 443        p->se.sum_sleep_runtime                 = 0;
 444        p->se.block_max                         = 0;
 445        p->se.exec_max                          = 0;
 446        p->se.slice_max                         = 0;
 447        p->se.nr_migrations                     = 0;
 448        p->se.nr_migrations_cold                = 0;
 449        p->se.nr_failed_migrations_affine       = 0;
 450        p->se.nr_failed_migrations_running      = 0;
 451        p->se.nr_failed_migrations_hot          = 0;
 452        p->se.nr_forced_migrations              = 0;
 453        p->se.nr_forced2_migrations             = 0;
 454        p->se.nr_wakeups                        = 0;
 455        p->se.nr_wakeups_sync                   = 0;
 456        p->se.nr_wakeups_migrate                = 0;
 457        p->se.nr_wakeups_local                  = 0;
 458        p->se.nr_wakeups_remote                 = 0;
 459        p->se.nr_wakeups_affine                 = 0;
 460        p->se.nr_wakeups_affine_attempts        = 0;
 461        p->se.nr_wakeups_passive                = 0;
 462        p->se.nr_wakeups_idle                   = 0;
 463        p->sched_info.bkl_count                 = 0;
 464#endif
 465        p->se.sum_exec_runtime                  = 0;
 466        p->se.prev_sum_exec_runtime             = 0;
 467        p->nvcsw                                = 0;
 468        p->nivcsw                               = 0;
 469}
 470