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->wait_start);
  74         PN(se->sleep_start);
  75         PN(se->block_start);
  76         PN(se->sleep_max);
  77         PN(se->block_max);
  78         PN(se->exec_max);
  79         PN(se->slice_max);
  80         PN(se->wait_max);
  81         PN(se->wait_sum);
  82         P(se->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.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 #elif defined(CONFIG_USER_SCHED) && defined(CONFIG_FAIR_GROUP_SCHED)
 177         {
 178                 uid_t uid = cfs_rq->tg->uid;
 179                 SEQ_printf(m, "\ncfs_rq[%d] for UID: %u\n", cpu, uid);
 180         }
 181 #else
 182         SEQ_printf(m, "\ncfs_rq[%d]:\n", cpu);
 183 #endif
 184         SEQ_printf(m, "  .%-30s: %Ld.%06ld\n", "exec_clock",
 185                         SPLIT_NS(cfs_rq->exec_clock));
 186
 187         raw_spin_lock_irqsave(&rq->lock, flags);
 188         if (cfs_rq->rb_leftmost)
 189                 MIN_vruntime = (__pick_next_entity(cfs_rq))->vruntime;
 190         last = __pick_last_entity(cfs_rq);
 191         if (last)
 192                 max_vruntime = last->vruntime;
 193         min_vruntime = cfs_rq->min_vruntime;
 194         rq0_min_vruntime = cpu_rq(0)->cfs.min_vruntime;
 195         raw_spin_unlock_irqrestore(&rq->lock, flags);
 196         SEQ_printf(m, "  .%-30s: %Ld.%06ld\n", "MIN_vruntime",
 197                         SPLIT_NS(MIN_vruntime));
 198         SEQ_printf(m, "  .%-30s: %Ld.%06ld\n", "min_vruntime",
 199                         SPLIT_NS(min_vruntime));
 200         SEQ_printf(m, "  .%-30s: %Ld.%06ld\n", "max_vruntime",
 201                         SPLIT_NS(max_vruntime));
 202         spread = max_vruntime - MIN_vruntime;
 203         SEQ_printf(m, "  .%-30s: %Ld.%06ld\n", "spread",
 204                         SPLIT_NS(spread));
 205         spread0 = min_vruntime - rq0_min_vruntime;
 206         SEQ_printf(m, "  .%-30s: %Ld.%06ld\n", "spread0",
 207                         SPLIT_NS(spread0));
 208         SEQ_printf(m, "  .%-30s: %ld\n", "nr_running", cfs_rq->nr_running);
 209         SEQ_printf(m, "  .%-30s: %ld\n", "load", cfs_rq->load.weight);
 210
 211         SEQ_printf(m, "  .%-30s: %d\n", "nr_spread_over",
 212                         cfs_rq->nr_spread_over);
 213 #ifdef CONFIG_FAIR_GROUP_SCHED
 214 #ifdef CONFIG_SMP
 215         SEQ_printf(m, "  .%-30s: %lu\n", "shares", cfs_rq->shares);
 216 #endif
 217         print_cfs_group_stats(m, cpu, cfs_rq->tg);
 218 #endif
 219 }
 220
 221 void print_rt_rq(struct seq_file *m, int cpu, struct rt_rq *rt_rq)
 222 {
 223 #if defined(CONFIG_CGROUP_SCHED) && defined(CONFIG_RT_GROUP_SCHED)
 224         char path[128];
 225         struct task_group *tg = rt_rq->tg;
 226
 227         task_group_path(tg, path, sizeof(path));
 228
 229         SEQ_printf(m, "\nrt_rq[%d]:%s\n", cpu, path);
 230 #else
 231         SEQ_printf(m, "\nrt_rq[%d]:\n", cpu);
 232 #endif
 233
 234
 235 #define P(x) \
 236         SEQ_printf(m, "  .%-30s: %Ld\n", #x, (long long)(rt_rq->x))
 237 #define PN(x) \
 238         SEQ_printf(m, "  .%-30s: %Ld.%06ld\n", #x, SPLIT_NS(rt_rq->x))
 239
 240         P(rt_nr_running);
 241         P(rt_throttled);
 242         PN(rt_time);
 243         PN(rt_runtime);
 244
 245 #undef PN
 246 #undef P
 247 }
 248
 249 static void print_cpu(struct seq_file *m, int cpu)
 250 {
 251         struct rq *rq = cpu_rq(cpu);
 252
 253 #ifdef CONFIG_X86
 254         {
 255                 unsigned int freq = cpu_khz ? : 1;
 256
 257                 SEQ_printf(m, "\ncpu#%d, %u.%03u MHz\n",
 258                            cpu, freq / 1000, (freq % 1000));
 259         }
 260 #else
 261         SEQ_printf(m, "\ncpu#%d\n", cpu);
 262 #endif
 263
 264 #define P(x) \
 265         SEQ_printf(m, "  .%-30s: %Ld\n", #x, (long long)(rq->x))
 266 #define PN(x) \
 267         SEQ_printf(m, "  .%-30s: %Ld.%06ld\n", #x, SPLIT_NS(rq->x))
 268
 269         P(nr_running);
 270         SEQ_printf(m, "  .%-30s: %lu\n", "load",
 271                    rq->load.weight);
 272         P(nr_switches);
 273         P(nr_load_updates);
 274         P(nr_uninterruptible);
 275         PN(next_balance);
 276         P(curr->pid);
 277         PN(clock);
 278         P(cpu_load[0]);
 279         P(cpu_load[1]);
 280         P(cpu_load[2]);
 281         P(cpu_load[3]);
 282         P(cpu_load[4]);
 283 #undef P
 284 #undef PN
 285
 286 #ifdef CONFIG_SCHEDSTATS
 287 #define P(n) SEQ_printf(m, "  .%-30s: %d\n", #n, rq->n);
 288 #define P64(n) SEQ_printf(m, "  .%-30s: %Ld\n", #n, rq->n);
 289
 290         P(yld_count);
 291
 292         P(sched_switch);
 293         P(sched_count);
 294         P(sched_goidle);
 295 #ifdef CONFIG_SMP
 296         P64(avg_idle);
 297 #endif
 298
 299         P(ttwu_count);
 300         P(ttwu_local);
 301
 302         P(bkl_count);
 303
 304 #undef P
 305 #endif
 306         print_cfs_stats(m, cpu);
 307         print_rt_stats(m, cpu);
 308
 309         print_rq(m, rq, cpu);
 310 }
 311
 312 static const char *sched_tunable_scaling_names[] = {
 313         "none",
 314         "logaritmic",
 315         "linear"
 316 };
 317
 318 static int sched_debug_show(struct seq_file *m, void *v)
 319 {
 320         u64 now = ktime_to_ns(ktime_get());
 321         int cpu;
 322
 323         SEQ_printf(m, "Sched Debug Version: v0.09, %s %.*s\n",
 324                 init_utsname()->release,
 325                 (int)strcspn(init_utsname()->version, " "),
 326                 init_utsname()->version);
 327
 328         SEQ_printf(m, "now at %Lu.%06ld msecs\n", SPLIT_NS(now));
 329
 330 #define P(x) \
 331         SEQ_printf(m, "  .%-40s: %Ld\n", #x, (long long)(x))
 332 #define PN(x) \
 333         SEQ_printf(m, "  .%-40s: %Ld.%06ld\n", #x, SPLIT_NS(x))
 334         P(jiffies);
 335         PN(sysctl_sched_latency);
 336         PN(sysctl_sched_min_granularity);
 337         PN(sysctl_sched_wakeup_granularity);
 338         PN(sysctl_sched_child_runs_first);
 339         P(sysctl_sched_features);
 340 #undef PN
 341 #undef P
 342
 343         SEQ_printf(m, "  .%-40s: %d (%s)\n", "sysctl_sched_tunable_scaling",
 344                 sysctl_sched_tunable_scaling,
 345                 sched_tunable_scaling_names[sysctl_sched_tunable_scaling]);
 346
 347         for_each_online_cpu(cpu)
 348                 print_cpu(m, cpu);
 349
 350         SEQ_printf(m, "\n");
 351
 352         return 0;
 353 }
 354
 355 static void sysrq_sched_debug_show(void)
 356 {
 357         sched_debug_show(NULL, NULL);
 358 }
 359
 360 static int sched_debug_open(struct inode *inode, struct file *filp)
 361 {
 362         return single_open(filp, sched_debug_show, NULL);
 363 }
 364
 365 static const struct file_operations sched_debug_fops = {
 366         .open           = sched_debug_open,
 367         .read           = seq_read,
 368         .llseek         = seq_lseek,
 369         .release        = single_release,
 370 };
 371
 372 static int __init init_sched_debug_procfs(void)
 373 {
 374         struct proc_dir_entry *pe;
 375
 376         pe = proc_create("sched_debug", 0444, NULL, &sched_debug_fops);
 377         if (!pe)
 378                 return -ENOMEM;
 379         return 0;
 380 }
 381
 382 __initcall(init_sched_debug_procfs);
 383
 384 void proc_sched_show_task(struct task_struct *p, struct seq_file *m)
 385 {
 386         unsigned long nr_switches;
 387         unsigned long flags;
 388         int num_threads = 1;
 389
 390         if (lock_task_sighand(p, &flags)) {
 391                 num_threads = atomic_read(&p->signal->count);
 392                 unlock_task_sighand(p, &flags);
 393         }
 394
 395         SEQ_printf(m, "%s (%d, #threads: %d)\n", p->comm, p->pid, num_threads);
 396         SEQ_printf(m,
 397                 "---------------------------------------------------------\n");
 398 #define __P(F) \
 399         SEQ_printf(m, "%-35s:%21Ld\n", #F, (long long)F)
 400 #define P(F) \
 401         SEQ_printf(m, "%-35s:%21Ld\n", #F, (long long)p->F)
 402 #define __PN(F) \
 403         SEQ_printf(m, "%-35s:%14Ld.%06ld\n", #F, SPLIT_NS((long long)F))
 404 #define PN(F) \
 405         SEQ_printf(m, "%-35s:%14Ld.%06ld\n", #F, SPLIT_NS((long long)p->F))
 406
 407         PN(se.exec_start);
 408         PN(se.vruntime);
 409         PN(se.sum_exec_runtime);
 410         PN(se.avg_overlap);
 411         PN(se.avg_wakeup);
 412
 413         nr_switches = p->nvcsw + p->nivcsw;
 414
 415 #ifdef CONFIG_SCHEDSTATS
 416         PN(se.wait_start);
 417         PN(se.sleep_start);
 418         PN(se.block_start);
 419         PN(se.sleep_max);
 420         PN(se.block_max);
 421         PN(se.exec_max);
 422         PN(se.slice_max);
 423         PN(se.wait_max);
 424         PN(se.wait_sum);
 425         P(se.wait_count);
 426         PN(se.iowait_sum);
 427         P(se.iowait_count);
 428         P(sched_info.bkl_count);
 429         P(se.nr_migrations);
 430         P(se.nr_migrations_cold);
 431         P(se.nr_failed_migrations_affine);
 432         P(se.nr_failed_migrations_running);
 433         P(se.nr_failed_migrations_hot);
 434         P(se.nr_forced_migrations);
 435         P(se.nr_wakeups);
 436         P(se.nr_wakeups_sync);
 437         P(se.nr_wakeups_migrate);
 438         P(se.nr_wakeups_local);
 439         P(se.nr_wakeups_remote);
 440         P(se.nr_wakeups_affine);
 441         P(se.nr_wakeups_affine_attempts);
 442         P(se.nr_wakeups_passive);
 443         P(se.nr_wakeups_idle);
 444
 445         {
 446                 u64 avg_atom, avg_per_cpu;
 447
 448                 avg_atom = p->se.sum_exec_runtime;
 449                 if (nr_switches)
 450                         do_div(avg_atom, nr_switches);
 451                 else
 452                         avg_atom = -1LL;
 453
 454                 avg_per_cpu = p->se.sum_exec_runtime;
 455                 if (p->se.nr_migrations) {
 456                         avg_per_cpu = div64_u64(avg_per_cpu,
 457                                                 p->se.nr_migrations);
 458                 } else {
 459                         avg_per_cpu = -1LL;
 460                 }
 461
 462                 __PN(avg_atom);
 463                 __PN(avg_per_cpu);
 464         }
 465 #endif
 466         __P(nr_switches);
 467         SEQ_printf(m, "%-35s:%21Ld\n",
 468                    "nr_voluntary_switches", (long long)p->nvcsw);
 469         SEQ_printf(m, "%-35s:%21Ld\n",
 470                    "nr_involuntary_switches", (long long)p->nivcsw);
 471
 472         P(se.load.weight);
 473         P(policy);
 474         P(prio);
 475 #undef PN
 476 #undef __PN
 477 #undef P
 478 #undef __P
 479
 480         {
 481                 unsigned int this_cpu = raw_smp_processor_id();
 482                 u64 t0, t1;
 483
 484                 t0 = cpu_clock(this_cpu);
 485                 t1 = cpu_clock(this_cpu);
 486                 SEQ_printf(m, "%-35s:%21Ld\n",
 487                            "clock-delta", (long long)(t1-t0));
 488         }
 489 }
 490
 491 void proc_sched_set_task(struct task_struct *p)
 492 {
 493 #ifdef CONFIG_SCHEDSTATS
 494         p->se.wait_max                          = 0;
 495         p->se.wait_sum                          = 0;
 496         p->se.wait_count                        = 0;
 497         p->se.iowait_sum                        = 0;
 498         p->se.iowait_count                      = 0;
 499         p->se.sleep_max                         = 0;
 500         p->se.sum_sleep_runtime                 = 0;
 501         p->se.block_max                         = 0;
 502         p->se.exec_max                          = 0;
 503         p->se.slice_max                         = 0;
 504         p->se.nr_migrations                     = 0;
 505         p->se.nr_migrations_cold                = 0;
 506         p->se.nr_failed_migrations_affine       = 0;
 507         p->se.nr_failed_migrations_running      = 0;
 508         p->se.nr_failed_migrations_hot          = 0;
 509         p->se.nr_forced_migrations              = 0;
 510         p->se.nr_wakeups                        = 0;
 511         p->se.nr_wakeups_sync                   = 0;
 512         p->se.nr_wakeups_migrate                = 0;
 513         p->se.nr_wakeups_local                  = 0;
 514         p->se.nr_wakeups_remote                 = 0;
 515         p->se.nr_wakeups_affine                 = 0;
 516         p->se.nr_wakeups_affine_attempts        = 0;
 517         p->se.nr_wakeups_passive                = 0;
 518         p->se.nr_wakeups_idle                   = 0;
 519         p->sched_info.bkl_count                 = 0;
 520 #endif
 521         p->se.sum_exec_runtime                  = 0;
 522         p->se.prev_sum_exec_runtime             = 0;
 523         p->nvcsw                                = 0;
 524         p->nivcsw                               = 0;
 525 }