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\n",
  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\n",
  76                0LL, 0LL, 0LL, 0L, 0LL, 0L, 0LL, 0L);
  77#endif
  78}
  79
  80static void print_rq(struct seq_file *m, struct rq *rq, int rq_cpu)
  81{
  82        struct task_struct *g, *p;
  83        unsigned long flags;
  84
  85        SEQ_printf(m,
  86        "\nrunnable tasks:\n"
  87        "            task   PID         tree-key  switches  prio"
  88        "     exec-runtime         sum-exec        sum-sleep\n"
  89        "------------------------------------------------------"
  90        "----------------------------------------------------\n");
  91
  92        read_lock_irqsave(&tasklist_lock, flags);
  93
  94        do_each_thread(g, p) {
  95                if (!p->se.on_rq || task_cpu(p) != rq_cpu)
  96                        continue;
  97
  98                print_task(m, rq, p);
  99        } while_each_thread(g, p);
 100
 101        read_unlock_irqrestore(&tasklist_lock, flags);
 102}
 103
 104void print_cfs_rq(struct seq_file *m, int cpu, struct cfs_rq *cfs_rq)
 105{
 106        s64 MIN_vruntime = -1, min_vruntime, max_vruntime = -1,
 107                spread, rq0_min_vruntime, spread0;
 108        struct rq *rq = &per_cpu(runqueues, cpu);
 109        struct sched_entity *last;
 110        unsigned long flags;
 111
 112        SEQ_printf(m, "\ncfs_rq\n");
 113
 114        SEQ_printf(m, "  .%-30s: %Ld.%06ld\n", "exec_clock",
 115                        SPLIT_NS(cfs_rq->exec_clock));
 116
 117        spin_lock_irqsave(&rq->lock, flags);
 118        if (cfs_rq->rb_leftmost)
 119                MIN_vruntime = (__pick_next_entity(cfs_rq))->vruntime;
 120        last = __pick_last_entity(cfs_rq);
 121        if (last)
 122                max_vruntime = last->vruntime;
 123        min_vruntime = rq->cfs.min_vruntime;
 124        rq0_min_vruntime = per_cpu(runqueues, 0).cfs.min_vruntime;
 125        spin_unlock_irqrestore(&rq->lock, flags);
 126        SEQ_printf(m, "  .%-30s: %Ld.%06ld\n", "MIN_vruntime",
 127                        SPLIT_NS(MIN_vruntime));
 128        SEQ_printf(m, "  .%-30s: %Ld.%06ld\n", "min_vruntime",
 129                        SPLIT_NS(min_vruntime));
 130        SEQ_printf(m, "  .%-30s: %Ld.%06ld\n", "max_vruntime",
 131                        SPLIT_NS(max_vruntime));
 132        spread = max_vruntime - MIN_vruntime;
 133        SEQ_printf(m, "  .%-30s: %Ld.%06ld\n", "spread",
 134                        SPLIT_NS(spread));
 135        spread0 = min_vruntime - rq0_min_vruntime;
 136        SEQ_printf(m, "  .%-30s: %Ld.%06ld\n", "spread0",
 137                        SPLIT_NS(spread0));
 138        SEQ_printf(m, "  .%-30s: %ld\n", "nr_running", cfs_rq->nr_running);
 139        SEQ_printf(m, "  .%-30s: %ld\n", "load", cfs_rq->load.weight);
 140#ifdef CONFIG_SCHEDSTATS
 141        SEQ_printf(m, "  .%-30s: %d\n", "bkl_count",
 142                        rq->bkl_count);
 143#endif
 144        SEQ_printf(m, "  .%-30s: %ld\n", "nr_spread_over",
 145                        cfs_rq->nr_spread_over);
 146}
 147
 148static void print_cpu(struct seq_file *m, int cpu)
 149{
 150        struct rq *rq = &per_cpu(runqueues, cpu);
 151
 152#ifdef CONFIG_X86
 153        {
 154                unsigned int freq = cpu_khz ? : 1;
 155
 156                SEQ_printf(m, "\ncpu#%d, %u.%03u MHz\n",
 157                           cpu, freq / 1000, (freq % 1000));
 158        }
 159#else
 160        SEQ_printf(m, "\ncpu#%d\n", cpu);
 161#endif
 162
 163#define P(x) \
 164        SEQ_printf(m, "  .%-30s: %Ld\n", #x, (long long)(rq->x))
 165#define PN(x) \
 166        SEQ_printf(m, "  .%-30s: %Ld.%06ld\n", #x, SPLIT_NS(rq->x))
 167
 168        P(nr_running);
 169        SEQ_printf(m, "  .%-30s: %lu\n", "load",
 170                   rq->load.weight);
 171        P(nr_switches);
 172        P(nr_load_updates);
 173        P(nr_uninterruptible);
 174        SEQ_printf(m, "  .%-30s: %lu\n", "jiffies", jiffies);
 175        PN(next_balance);
 176        P(curr->pid);
 177        PN(clock);
 178        PN(idle_clock);
 179        PN(prev_clock_raw);
 180        P(clock_warps);
 181        P(clock_overflows);
 182        P(clock_underflows);
 183        P(clock_deep_idle_events);
 184        PN(clock_max_delta);
 185        P(cpu_load[0]);
 186        P(cpu_load[1]);
 187        P(cpu_load[2]);
 188        P(cpu_load[3]);
 189        P(cpu_load[4]);
 190#undef P
 191#undef PN
 192
 193        print_cfs_stats(m, cpu);
 194
 195        print_rq(m, rq, cpu);
 196}
 197
 198static int sched_debug_show(struct seq_file *m, void *v)
 199{
 200        u64 now = ktime_to_ns(ktime_get());
 201        int cpu;
 202
 203        SEQ_printf(m, "Sched Debug Version: v0.07, %s %.*s\n",
 204                init_utsname()->release,
 205                (int)strcspn(init_utsname()->version, " "),
 206                init_utsname()->version);
 207
 208        SEQ_printf(m, "now at %Lu.%06ld msecs\n", SPLIT_NS(now));
 209
 210#define P(x) \
 211        SEQ_printf(m, "  .%-40s: %Ld\n", #x, (long long)(x))
 212#define PN(x) \
 213        SEQ_printf(m, "  .%-40s: %Ld.%06ld\n", #x, SPLIT_NS(x))
 214        PN(sysctl_sched_latency);
 215        PN(sysctl_sched_min_granularity);
 216        PN(sysctl_sched_wakeup_granularity);
 217        PN(sysctl_sched_batch_wakeup_granularity);
 218        PN(sysctl_sched_child_runs_first);
 219        P(sysctl_sched_features);
 220#undef PN
 221#undef P
 222
 223        for_each_online_cpu(cpu)
 224                print_cpu(m, cpu);
 225
 226        SEQ_printf(m, "\n");
 227
 228        return 0;
 229}
 230
 231static void sysrq_sched_debug_show(void)
 232{
 233        sched_debug_show(NULL, NULL);
 234}
 235
 236static int sched_debug_open(struct inode *inode, struct file *filp)
 237{
 238        return single_open(filp, sched_debug_show, NULL);
 239}
 240
 241static const struct file_operations sched_debug_fops = {
 242        .open           = sched_debug_open,
 243        .read           = seq_read,
 244        .llseek         = seq_lseek,
 245        .release        = single_release,
 246};
 247
 248static int __init init_sched_debug_procfs(void)
 249{
 250        struct proc_dir_entry *pe;
 251
 252        pe = create_proc_entry("sched_debug", 0644, NULL);
 253        if (!pe)
 254                return -ENOMEM;
 255
 256        pe->proc_fops = &sched_debug_fops;
 257
 258        return 0;
 259}
 260
 261__initcall(init_sched_debug_procfs);
 262
 263void proc_sched_show_task(struct task_struct *p, struct seq_file *m)
 264{
 265        unsigned long nr_switches;
 266        unsigned long flags;
 267        int num_threads = 1;
 268
 269        rcu_read_lock();
 270        if (lock_task_sighand(p, &flags)) {
 271                num_threads = atomic_read(&p->signal->count);
 272                unlock_task_sighand(p, &flags);
 273        }
 274        rcu_read_unlock();
 275
 276        SEQ_printf(m, "%s (%d, #threads: %d)\n", p->comm, p->pid, num_threads);
 277        SEQ_printf(m,
 278                "---------------------------------------------------------\n");
 279#define __P(F) \
 280        SEQ_printf(m, "%-35s:%21Ld\n", #F, (long long)F)
 281#define P(F) \
 282        SEQ_printf(m, "%-35s:%21Ld\n", #F, (long long)p->F)
 283#define __PN(F) \
 284        SEQ_printf(m, "%-35s:%14Ld.%06ld\n", #F, SPLIT_NS((long long)F))
 285#define PN(F) \
 286        SEQ_printf(m, "%-35s:%14Ld.%06ld\n", #F, SPLIT_NS((long long)p->F))
 287
 288        PN(se.exec_start);
 289        PN(se.vruntime);
 290        PN(se.sum_exec_runtime);
 291        PN(se.avg_overlap);
 292
 293        nr_switches = p->nvcsw + p->nivcsw;
 294
 295#ifdef CONFIG_SCHEDSTATS
 296        PN(se.wait_start);
 297        PN(se.sleep_start);
 298        PN(se.block_start);
 299        PN(se.sleep_max);
 300        PN(se.block_max);
 301        PN(se.exec_max);
 302        PN(se.slice_max);
 303        PN(se.wait_max);
 304        PN(se.wait_sum);
 305        P(se.wait_count);
 306        P(sched_info.bkl_count);
 307        P(se.nr_migrations);
 308        P(se.nr_migrations_cold);
 309        P(se.nr_failed_migrations_affine);
 310        P(se.nr_failed_migrations_running);
 311        P(se.nr_failed_migrations_hot);
 312        P(se.nr_forced_migrations);
 313        P(se.nr_forced2_migrations);
 314        P(se.nr_wakeups);
 315        P(se.nr_wakeups_sync);
 316        P(se.nr_wakeups_migrate);
 317        P(se.nr_wakeups_local);
 318        P(se.nr_wakeups_remote);
 319        P(se.nr_wakeups_affine);
 320        P(se.nr_wakeups_affine_attempts);
 321        P(se.nr_wakeups_passive);
 322        P(se.nr_wakeups_idle);
 323
 324        {
 325                u64 avg_atom, avg_per_cpu;
 326
 327                avg_atom = p->se.sum_exec_runtime;
 328                if (nr_switches)
 329                        do_div(avg_atom, nr_switches);
 330                else
 331                        avg_atom = -1LL;
 332
 333                avg_per_cpu = p->se.sum_exec_runtime;
 334                if (p->se.nr_migrations) {
 335                        avg_per_cpu = div64_64(avg_per_cpu,
 336                                               p->se.nr_migrations);
 337                } else {
 338                        avg_per_cpu = -1LL;
 339                }
 340
 341                __PN(avg_atom);
 342                __PN(avg_per_cpu);
 343        }
 344#endif
 345        __P(nr_switches);
 346        SEQ_printf(m, "%-35s:%21Ld\n",
 347                   "nr_voluntary_switches", (long long)p->nvcsw);
 348        SEQ_printf(m, "%-35s:%21Ld\n",
 349                   "nr_involuntary_switches", (long long)p->nivcsw);
 350
 351        P(se.load.weight);
 352        P(policy);
 353        P(prio);
 354#undef PN
 355#undef __PN
 356#undef P
 357#undef __P
 358
 359        {
 360                u64 t0, t1;
 361
 362                t0 = sched_clock();
 363                t1 = sched_clock();
 364                SEQ_printf(m, "%-35s:%21Ld\n",
 365                           "clock-delta", (long long)(t1-t0));
 366        }
 367}
 368
 369void proc_sched_set_task(struct task_struct *p)
 370{
 371#ifdef CONFIG_SCHEDSTATS
 372        p->se.wait_max                          = 0;
 373        p->se.wait_sum                          = 0;
 374        p->se.wait_count                        = 0;
 375        p->se.sleep_max                         = 0;
 376        p->se.sum_sleep_runtime                 = 0;
 377        p->se.block_max                         = 0;
 378        p->se.exec_max                          = 0;
 379        p->se.slice_max                         = 0;
 380        p->se.nr_migrations                     = 0;
 381        p->se.nr_migrations_cold                = 0;
 382        p->se.nr_failed_migrations_affine       = 0;
 383        p->se.nr_failed_migrations_running      = 0;
 384        p->se.nr_failed_migrations_hot          = 0;
 385        p->se.nr_forced_migrations              = 0;
 386        p->se.nr_forced2_migrations             = 0;
 387        p->se.nr_wakeups                        = 0;
 388        p->se.nr_wakeups_sync                   = 0;
 389        p->se.nr_wakeups_migrate                = 0;
 390        p->se.nr_wakeups_local                  = 0;
 391        p->se.nr_wakeups_remote                 = 0;
 392        p->se.nr_wakeups_affine                 = 0;
 393        p->se.nr_wakeups_affine_attempts        = 0;
 394        p->se.nr_wakeups_passive                = 0;
 395        p->se.nr_wakeups_idle                   = 0;
 396        p->sched_info.bkl_count                 = 0;
 397#endif
 398        p->se.sum_exec_runtime                  = 0;
 399        p->se.prev_sum_exec_runtime             = 0;
 400        p->nvcsw                                = 0;
 401        p->nivcsw                               = 0;
 402}
 403
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