linux/kernel/sched_debug.c
<<
>>
Prefs
   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_USER_SCHED)
 123        SEQ_printf(m, "\ncfs_rq[%d]:\n", cpu);
 124#else
 125        char path[128] = "";
 126        struct cgroup *cgroup = NULL;
 127        struct task_group *tg = cfs_rq->tg;
 128
 129        if (tg)
 130                cgroup = tg->css.cgroup;
 131
 132        if (cgroup)
 133                cgroup_path(cgroup, path, sizeof(path));
 134
 135        SEQ_printf(m, "\ncfs_rq[%d]:%s\n", cpu, path);
 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 = rq->cfs.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#ifdef CONFIG_SCHEDSTATS
 165        SEQ_printf(m, "  .%-30s: %d\n", "bkl_count",
 166                        rq->bkl_count);
 167#endif
 168        SEQ_printf(m, "  .%-30s: %ld\n", "nr_spread_over",
 169                        cfs_rq->nr_spread_over);
 170}
 171
 172static void print_cpu(struct seq_file *m, int cpu)
 173{
 174        struct rq *rq = &per_cpu(runqueues, cpu);
 175
 176#ifdef CONFIG_X86
 177        {
 178                unsigned int freq = cpu_khz ? : 1;
 179
 180                SEQ_printf(m, "\ncpu#%d, %u.%03u MHz\n",
 181                           cpu, freq / 1000, (freq % 1000));
 182        }
 183#else
 184        SEQ_printf(m, "\ncpu#%d\n", cpu);
 185#endif
 186
 187#define P(x) \
 188        SEQ_printf(m, "  .%-30s: %Ld\n", #x, (long long)(rq->x))
 189#define PN(x) \
 190        SEQ_printf(m, "  .%-30s: %Ld.%06ld\n", #x, SPLIT_NS(rq->x))
 191
 192        P(nr_running);
 193        SEQ_printf(m, "  .%-30s: %lu\n", "load",
 194                   rq->load.weight);
 195        P(nr_switches);
 196        P(nr_load_updates);
 197        P(nr_uninterruptible);
 198        SEQ_printf(m, "  .%-30s: %lu\n", "jiffies", jiffies);
 199        PN(next_balance);
 200        P(curr->pid);
 201        PN(clock);
 202        P(cpu_load[0]);
 203        P(cpu_load[1]);
 204        P(cpu_load[2]);
 205        P(cpu_load[3]);
 206        P(cpu_load[4]);
 207#undef P
 208#undef PN
 209
 210        print_cfs_stats(m, cpu);
 211
 212        print_rq(m, rq, cpu);
 213}
 214
 215static int sched_debug_show(struct seq_file *m, void *v)
 216{
 217        u64 now = ktime_to_ns(ktime_get());
 218        int cpu;
 219
 220        SEQ_printf(m, "Sched Debug Version: v0.07, %s %.*s\n",
 221                init_utsname()->release,
 222                (int)strcspn(init_utsname()->version, " "),
 223                init_utsname()->version);
 224
 225        SEQ_printf(m, "now at %Lu.%06ld msecs\n", SPLIT_NS(now));
 226
 227#define P(x) \
 228        SEQ_printf(m, "  .%-40s: %Ld\n", #x, (long long)(x))
 229#define PN(x) \
 230        SEQ_printf(m, "  .%-40s: %Ld.%06ld\n", #x, SPLIT_NS(x))
 231        PN(sysctl_sched_latency);
 232        PN(sysctl_sched_min_granularity);
 233        PN(sysctl_sched_wakeup_granularity);
 234        PN(sysctl_sched_child_runs_first);
 235        P(sysctl_sched_features);
 236#undef PN
 237#undef P
 238
 239        for_each_online_cpu(cpu)
 240                print_cpu(m, cpu);
 241
 242        SEQ_printf(m, "\n");
 243
 244        return 0;
 245}
 246
 247static void sysrq_sched_debug_show(void)
 248{
 249        sched_debug_show(NULL, NULL);
 250}
 251
 252static int sched_debug_open(struct inode *inode, struct file *filp)
 253{
 254        return single_open(filp, sched_debug_show, NULL);
 255}
 256
 257static const struct file_operations sched_debug_fops = {
 258        .open           = sched_debug_open,
 259        .read           = seq_read,
 260        .llseek         = seq_lseek,
 261        .release        = single_release,
 262};
 263
 264static int __init init_sched_debug_procfs(void)
 265{
 266        struct proc_dir_entry *pe;
 267
 268        pe = proc_create("sched_debug", 0644, NULL, &sched_debug_fops);
 269        if (!pe)
 270                return -ENOMEM;
 271        return 0;
 272}
 273
 274__initcall(init_sched_debug_procfs);
 275
 276void proc_sched_show_task(struct task_struct *p, struct seq_file *m)
 277{
 278        unsigned long nr_switches;
 279        unsigned long flags;
 280        int num_threads = 1;
 281
 282        rcu_read_lock();
 283        if (lock_task_sighand(p, &flags)) {
 284                num_threads = atomic_read(&p->signal->count);
 285                unlock_task_sighand(p, &flags);
 286        }
 287        rcu_read_unlock();
 288
 289        SEQ_printf(m, "%s (%d, #threads: %d)\n", p->comm, p->pid, num_threads);
 290        SEQ_printf(m,
 291                "---------------------------------------------------------\n");
 292#define __P(F) \
 293        SEQ_printf(m, "%-35s:%21Ld\n", #F, (long long)F)
 294#define P(F) \
 295        SEQ_printf(m, "%-35s:%21Ld\n", #F, (long long)p->F)
 296#define __PN(F) \
 297        SEQ_printf(m, "%-35s:%14Ld.%06ld\n", #F, SPLIT_NS((long long)F))
 298#define PN(F) \
 299        SEQ_printf(m, "%-35s:%14Ld.%06ld\n", #F, SPLIT_NS((long long)p->F))
 300
 301        PN(se.exec_start);
 302        PN(se.vruntime);
 303        PN(se.sum_exec_runtime);
 304        PN(se.avg_overlap);
 305
 306        nr_switches = p->nvcsw + p->nivcsw;
 307
 308#ifdef CONFIG_SCHEDSTATS
 309        PN(se.wait_start);
 310        PN(se.sleep_start);
 311        PN(se.block_start);
 312        PN(se.sleep_max);
 313        PN(se.block_max);
 314        PN(se.exec_max);
 315        PN(se.slice_max);
 316        PN(se.wait_max);
 317        PN(se.wait_sum);
 318        P(se.wait_count);
 319        P(sched_info.bkl_count);
 320        P(se.nr_migrations);
 321        P(se.nr_migrations_cold);
 322        P(se.nr_failed_migrations_affine);
 323        P(se.nr_failed_migrations_running);
 324        P(se.nr_failed_migrations_hot);
 325        P(se.nr_forced_migrations);
 326        P(se.nr_forced2_migrations);
 327        P(se.nr_wakeups);
 328        P(se.nr_wakeups_sync);
 329        P(se.nr_wakeups_migrate);
 330        P(se.nr_wakeups_local);
 331        P(se.nr_wakeups_remote);
 332        P(se.nr_wakeups_affine);
 333        P(se.nr_wakeups_affine_attempts);
 334        P(se.nr_wakeups_passive);
 335        P(se.nr_wakeups_idle);
 336
 337        {
 338                u64 avg_atom, avg_per_cpu;
 339
 340                avg_atom = p->se.sum_exec_runtime;
 341                if (nr_switches)
 342                        do_div(avg_atom, nr_switches);
 343                else
 344                        avg_atom = -1LL;
 345
 346                avg_per_cpu = p->se.sum_exec_runtime;
 347                if (p->se.nr_migrations) {
 348                        avg_per_cpu = div64_u64(avg_per_cpu,
 349                                                p->se.nr_migrations);
 350                } else {
 351                        avg_per_cpu = -1LL;
 352                }
 353
 354                __PN(avg_atom);
 355                __PN(avg_per_cpu);
 356        }
 357#endif
 358        __P(nr_switches);
 359        SEQ_printf(m, "%-35s:%21Ld\n",
 360                   "nr_voluntary_switches", (long long)p->nvcsw);
 361        SEQ_printf(m, "%-35s:%21Ld\n",
 362                   "nr_involuntary_switches", (long long)p->nivcsw);
 363
 364        P(se.load.weight);
 365        P(policy);
 366        P(prio);
 367#undef PN
 368#undef __PN
 369#undef P
 370#undef __P
 371
 372        {
 373                u64 t0, t1;
 374
 375                t0 = sched_clock();
 376                t1 = sched_clock();
 377                SEQ_printf(m, "%-35s:%21Ld\n",
 378                           "clock-delta", (long long)(t1-t0));
 379        }
 380}
 381
 382void proc_sched_set_task(struct task_struct *p)
 383{
 384#ifdef CONFIG_SCHEDSTATS
 385        p->se.wait_max                          = 0;
 386        p->se.wait_sum                          = 0;
 387        p->se.wait_count                        = 0;
 388        p->se.sleep_max                         = 0;
 389        p->se.sum_sleep_runtime                 = 0;
 390        p->se.block_max                         = 0;
 391        p->se.exec_max                          = 0;
 392        p->se.slice_max                         = 0;
 393        p->se.nr_migrations                     = 0;
 394        p->se.nr_migrations_cold                = 0;
 395        p->se.nr_failed_migrations_affine       = 0;
 396        p->se.nr_failed_migrations_running      = 0;
 397        p->se.nr_failed_migrations_hot          = 0;
 398        p->se.nr_forced_migrations              = 0;
 399        p->se.nr_forced2_migrations             = 0;
 400        p->se.nr_wakeups                        = 0;
 401        p->se.nr_wakeups_sync                   = 0;
 402        p->se.nr_wakeups_migrate                = 0;
 403        p->se.nr_wakeups_local                  = 0;
 404        p->se.nr_wakeups_remote                 = 0;
 405        p->se.nr_wakeups_affine                 = 0;
 406        p->se.nr_wakeups_affine_attempts        = 0;
 407        p->se.nr_wakeups_passive                = 0;
 408        p->se.nr_wakeups_idle                   = 0;
 409        p->sched_info.bkl_count                 = 0;
 410#endif
 411        p->se.sum_exec_runtime                  = 0;
 412        p->se.prev_sum_exec_runtime             = 0;
 413        p->nvcsw                                = 0;
 414        p->nivcsw                               = 0;
 415}
 416
lxr.linux.no kindly hosted by Redpill Linpro AS, provider of Linux consulting and operations services since 1995.