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  */
  34 static 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
  46 static 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
  57 static 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
  90 static void
  91 print_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                 cgroup_path(task_group(p)->css.cgroup, path, sizeof(path));
 118                 SEQ_printf(m, " %s", path);
 119         }
 120 #endif
 121         SEQ_printf(m, "\n");
 122 }
 123
 124 static void print_rq(struct seq_file *m, struct rq *rq, int rq_cpu)
 125 {
 126         struct task_struct *g, *p;
 127         unsigned long flags;
 128
 129         SEQ_printf(m,
 130         "\nrunnable tasks:\n"
 131         "            task   PID         tree-key  switches  prio"
 132         "     exec-runtime         sum-exec        sum-sleep\n"
 133         "------------------------------------------------------"
 134         "----------------------------------------------------\n");
 135
 136         read_lock_irqsave(&tasklist_lock, flags);
 137
 138         do_each_thread(g, p) {
 139                 if (!p->se.on_rq || task_cpu(p) != rq_cpu)
 140                         continue;
 141
 142                 print_task(m, rq, p);
 143         } while_each_thread(g, p);
 144
 145         read_unlock_irqrestore(&tasklist_lock, flags);
 146 }
 147
 148 #if defined(CONFIG_CGROUP_SCHED) && \
 149         (defined(CONFIG_FAIR_GROUP_SCHED) || defined(CONFIG_RT_GROUP_SCHED))
 150 static void task_group_path(struct task_group *tg, char *buf, int buflen)
 151 {
 152         /* may be NULL if the underlying cgroup isn't fully-created yet */
 153         if (!tg->css.cgroup) {
 154                 buf[0] = '\0';
 155                 return;
 156         }
 157         cgroup_path(tg->css.cgroup, buf, buflen);
 158 }
 159 #endif
 160
 161 void print_cfs_rq(struct seq_file *m, int cpu, struct cfs_rq *cfs_rq)
 162 {
 163         s64 MIN_vruntime = -1, min_vruntime, max_vruntime = -1,
 164                 spread, rq0_min_vruntime, spread0;
 165         struct rq *rq = cpu_rq(cpu);
 166         struct sched_entity *last;
 167         unsigned long flags;
 168
 169 #if defined(CONFIG_CGROUP_SCHED) && defined(CONFIG_FAIR_GROUP_SCHED)
 170         char path[128];
 171         struct task_group *tg = cfs_rq->tg;
 172
 173         task_group_path(tg, path, sizeof(path));
 174
 175         SEQ_printf(m, "\ncfs_rq[%d]:%s\n", cpu, path);
 176 #else
 177         SEQ_printf(m, "\ncfs_rq[%d]:\n", cpu);
 178 #endif
 179         SEQ_printf(m, "  .%-30s: %Ld.%06ld\n", "exec_clock",
 180                         SPLIT_NS(cfs_rq->exec_clock));
 181
 182         raw_spin_lock_irqsave(&rq->lock, flags);
 183         if (cfs_rq->rb_leftmost)
 184                 MIN_vruntime = (__pick_next_entity(cfs_rq))->vruntime;
 185         last = __pick_last_entity(cfs_rq);
 186         if (last)
 187                 max_vruntime = last->vruntime;
 188         min_vruntime = cfs_rq->min_vruntime;
 189         rq0_min_vruntime = cpu_rq(0)->cfs.min_vruntime;
 190         raw_spin_unlock_irqrestore(&rq->lock, flags);
 191         SEQ_printf(m, "  .%-30s: %Ld.%06ld\n", "MIN_vruntime",
 192                         SPLIT_NS(MIN_vruntime));
 193         SEQ_printf(m, "  .%-30s: %Ld.%06ld\n", "min_vruntime",
 194                         SPLIT_NS(min_vruntime));
 195         SEQ_printf(m, "  .%-30s: %Ld.%06ld\n", "max_vruntime",
 196                         SPLIT_NS(max_vruntime));
 197         spread = max_vruntime - MIN_vruntime;
 198         SEQ_printf(m, "  .%-30s: %Ld.%06ld\n", "spread",
 199                         SPLIT_NS(spread));
 200         spread0 = min_vruntime - rq0_min_vruntime;
 201         SEQ_printf(m, "  .%-30s: %Ld.%06ld\n", "spread0",
 202                         SPLIT_NS(spread0));
 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
 206         SEQ_printf(m, "  .%-30s: %d\n", "nr_spread_over",
 207                         cfs_rq->nr_spread_over);
 208 #ifdef CONFIG_FAIR_GROUP_SCHED
 209 #ifdef CONFIG_SMP
 210         SEQ_printf(m, "  .%-30s: %lu\n", "shares", cfs_rq->shares);
 211 #endif
 212         print_cfs_group_stats(m, cpu, cfs_rq->tg);
 213 #endif
 214 }
 215
 216 void print_rt_rq(struct seq_file *m, int cpu, struct rt_rq *rt_rq)
 217 {
 218 #if defined(CONFIG_CGROUP_SCHED) && defined(CONFIG_RT_GROUP_SCHED)
 219         char path[128];
 220         struct task_group *tg = rt_rq->tg;
 221
 222         task_group_path(tg, path, sizeof(path));
 223
 224         SEQ_printf(m, "\nrt_rq[%d]:%s\n", cpu, path);
 225 #else
 226         SEQ_printf(m, "\nrt_rq[%d]:\n", cpu);
 227 #endif
 228
 229
 230 #define P(x) \
 231         SEQ_printf(m, "  .%-30s: %Ld\n", #x, (long long)(rt_rq->x))
 232 #define PN(x) \
 233         SEQ_printf(m, "  .%-30s: %Ld.%06ld\n", #x, SPLIT_NS(rt_rq->x))
 234
 235         P(rt_nr_running);
 236         P(rt_throttled);
 237         PN(rt_time);
 238         PN(rt_runtime);
 239
 240 #undef PN
 241 #undef P
 242 }
 243
 244 static void print_cpu(struct seq_file *m, int cpu)
 245 {
 246         struct rq *rq = cpu_rq(cpu);
 247
 248 #ifdef CONFIG_X86
 249         {
 250                 unsigned int freq = cpu_khz ? : 1;
 251
 252                 SEQ_printf(m, "\ncpu#%d, %u.%03u MHz\n",
 253                            cpu, freq / 1000, (freq % 1000));
 254         }
 255 #else
 256         SEQ_printf(m, "\ncpu#%d\n", cpu);
 257 #endif
 258
 259 #define P(x) \
 260         SEQ_printf(m, "  .%-30s: %Ld\n", #x, (long long)(rq->x))
 261 #define PN(x) \
 262         SEQ_printf(m, "  .%-30s: %Ld.%06ld\n", #x, SPLIT_NS(rq->x))
 263
 264         P(nr_running);
 265         SEQ_printf(m, "  .%-30s: %lu\n", "load",
 266                    rq->load.weight);
 267         P(nr_switches);
 268         P(nr_load_updates);
 269         P(nr_uninterruptible);
 270         PN(next_balance);
 271         P(curr->pid);
 272         PN(clock);
 273         P(cpu_load[0]);
 274         P(cpu_load[1]);
 275         P(cpu_load[2]);
 276         P(cpu_load[3]);
 277         P(cpu_load[4]);
 278 #undef P
 279 #undef PN
 280
 281 #ifdef CONFIG_SCHEDSTATS
 282 #define P(n) SEQ_printf(m, "  .%-30s: %d\n", #n, rq->n);
 283 #define P64(n) SEQ_printf(m, "  .%-30s: %Ld\n", #n, rq->n);
 284
 285         P(yld_count);
 286
 287         P(sched_switch);
 288         P(sched_count);
 289         P(sched_goidle);
 290 #ifdef CONFIG_SMP
 291         P64(avg_idle);
 292 #endif
 293
 294         P(ttwu_count);
 295         P(ttwu_local);
 296
 297         P(bkl_count);
 298
 299 #undef P
 300 #endif
 301         print_cfs_stats(m, cpu);
 302         print_rt_stats(m, cpu);
 303
 304         print_rq(m, rq, cpu);
 305 }
 306
 307 static const char *sched_tunable_scaling_names[] = {
 308         "none",
 309         "logaritmic",
 310         "linear"
 311 };
 312
 313 static int sched_debug_show(struct seq_file *m, void *v)
 314 {
 315         u64 now = ktime_to_ns(ktime_get());
 316         int cpu;
 317
 318         SEQ_printf(m, "Sched Debug Version: v0.09, %s %.*s\n",
 319                 init_utsname()->release,
 320                 (int)strcspn(init_utsname()->version, " "),
 321                 init_utsname()->version);
 322
 323         SEQ_printf(m, "now at %Lu.%06ld msecs\n", SPLIT_NS(now));
 324
 325 #define P(x) \
 326         SEQ_printf(m, "  .%-40s: %Ld\n", #x, (long long)(x))
 327 #define PN(x) \
 328         SEQ_printf(m, "  .%-40s: %Ld.%06ld\n", #x, SPLIT_NS(x))
 329         P(jiffies);
 330         PN(sysctl_sched_latency);
 331         PN(sysctl_sched_min_granularity);
 332         PN(sysctl_sched_wakeup_granularity);
 333         PN(sysctl_sched_child_runs_first);
 334         P(sysctl_sched_features);
 335 #undef PN
 336 #undef P
 337
 338         SEQ_printf(m, "  .%-40s: %d (%s)\n", "sysctl_sched_tunable_scaling",
 339                 sysctl_sched_tunable_scaling,
 340                 sched_tunable_scaling_names[sysctl_sched_tunable_scaling]);
 341
 342         for_each_online_cpu(cpu)
 343                 print_cpu(m, cpu);
 344
 345         SEQ_printf(m, "\n");
 346
 347         return 0;
 348 }
 349
 350 static void sysrq_sched_debug_show(void)
 351 {
 352         sched_debug_show(NULL, NULL);
 353 }
 354
 355 static int sched_debug_open(struct inode *inode, struct file *filp)
 356 {
 357         return single_open(filp, sched_debug_show, NULL);
 358 }
 359
 360 static const struct file_operations sched_debug_fops = {
 361         .open           = sched_debug_open,
 362         .read           = seq_read,
 363         .llseek         = seq_lseek,
 364         .release        = single_release,
 365 };
 366
 367 static int __init init_sched_debug_procfs(void)
 368 {
 369         struct proc_dir_entry *pe;
 370
 371         pe = proc_create("sched_debug", 0444, NULL, &sched_debug_fops);
 372         if (!pe)
 373                 return -ENOMEM;
 374         return 0;
 375 }
 376
 377 __initcall(init_sched_debug_procfs);
 378
 379 void proc_sched_show_task(struct task_struct *p, struct seq_file *m)
 380 {
 381         unsigned long nr_switches;
 382         unsigned long flags;
 383         int num_threads = 1;
 384
 385         if (lock_task_sighand(p, &flags)) {
 386                 num_threads = atomic_read(&p->signal->count);
 387                 unlock_task_sighand(p, &flags);
 388         }
 389
 390         SEQ_printf(m, "%s (%d, #threads: %d)\n", p->comm, p->pid, num_threads);
 391         SEQ_printf(m,
 392                 "---------------------------------------------------------\n");
 393 #define __P(F) \
 394         SEQ_printf(m, "%-35s:%21Ld\n", #F, (long long)F)
 395 #define P(F) \
 396         SEQ_printf(m, "%-35s:%21Ld\n", #F, (long long)p->F)
 397 #define __PN(F) \
 398         SEQ_printf(m, "%-35s:%14Ld.%06ld\n", #F, SPLIT_NS((long long)F))
 399 #define PN(F) \
 400         SEQ_printf(m, "%-35s:%14Ld.%06ld\n", #F, SPLIT_NS((long long)p->F))
 401
 402         PN(se.exec_start);
 403         PN(se.vruntime);
 404         PN(se.sum_exec_runtime);
 405
 406         nr_switches = p->nvcsw + p->nivcsw;
 407
 408 #ifdef CONFIG_SCHEDSTATS
 409         PN(se.statistics.wait_start);
 410         PN(se.statistics.sleep_start);
 411         PN(se.statistics.block_start);
 412         PN(se.statistics.sleep_max);
 413         PN(se.statistics.block_max);
 414         PN(se.statistics.exec_max);
 415         PN(se.statistics.slice_max);
 416         PN(se.statistics.wait_max);
 417         PN(se.statistics.wait_sum);
 418         P(se.statistics.wait_count);
 419         PN(se.statistics.iowait_sum);
 420         P(se.statistics.iowait_count);
 421         P(sched_info.bkl_count);
 422         P(se.nr_migrations);
 423         P(se.statistics.nr_migrations_cold);
 424         P(se.statistics.nr_failed_migrations_affine);
 425         P(se.statistics.nr_failed_migrations_running);
 426         P(se.statistics.nr_failed_migrations_hot);
 427         P(se.statistics.nr_forced_migrations);
 428         P(se.statistics.nr_wakeups);
 429         P(se.statistics.nr_wakeups_sync);
 430         P(se.statistics.nr_wakeups_migrate);
 431         P(se.statistics.nr_wakeups_local);
 432         P(se.statistics.nr_wakeups_remote);
 433         P(se.statistics.nr_wakeups_affine);
 434         P(se.statistics.nr_wakeups_affine_attempts);
 435         P(se.statistics.nr_wakeups_passive);
 436         P(se.statistics.nr_wakeups_idle);
 437
 438         {
 439                 u64 avg_atom, avg_per_cpu;
 440
 441                 avg_atom = p->se.sum_exec_runtime;
 442                 if (nr_switches)
 443                         do_div(avg_atom, nr_switches);
 444                 else
 445                         avg_atom = -1LL;
 446
 447                 avg_per_cpu = p->se.sum_exec_runtime;
 448                 if (p->se.nr_migrations) {
 449                         avg_per_cpu = div64_u64(avg_per_cpu,
 450                                                 p->se.nr_migrations);
 451                 } else {
 452                         avg_per_cpu = -1LL;
 453                 }
 454
 455                 __PN(avg_atom);
 456                 __PN(avg_per_cpu);
 457         }
 458 #endif
 459         __P(nr_switches);
 460         SEQ_printf(m, "%-35s:%21Ld\n",
 461                    "nr_voluntary_switches", (long long)p->nvcsw);
 462         SEQ_printf(m, "%-35s:%21Ld\n",
 463                    "nr_involuntary_switches", (long long)p->nivcsw);
 464
 465         P(se.load.weight);
 466         P(policy);
 467         P(prio);
 468 #undef PN
 469 #undef __PN
 470 #undef P
 471 #undef __P
 472
 473         {
 474                 unsigned int this_cpu = raw_smp_processor_id();
 475                 u64 t0, t1;
 476
 477                 t0 = cpu_clock(this_cpu);
 478                 t1 = cpu_clock(this_cpu);
 479                 SEQ_printf(m, "%-35s:%21Ld\n",
 480                            "clock-delta", (long long)(t1-t0));
 481         }
 482 }
 483
 484 void proc_sched_set_task(struct task_struct *p)
 485 {
 486 #ifdef CONFIG_SCHEDSTATS
 487         memset(&p->se.statistics, 0, sizeof(p->se.statistics));
 488 #endif
 489         p->se.sum_exec_runtime                  = 0;
 490         p->se.prev_sum_exec_runtime             = 0;
 491         p->nvcsw                                = 0;
 492         p->nivcsw                               = 0;
 493 }