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 static void
  57 print_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
  90 static 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
 114 void 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 = 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 #define P(n) SEQ_printf(m, "  .%-30s: %d\n", #n, rq->n);
 166
 167         P(yld_exp_empty);
 168         P(yld_act_empty);
 169         P(yld_both_empty);
 170         P(yld_count);
 171
 172         P(sched_switch);
 173         P(sched_count);
 174         P(sched_goidle);
 175
 176         P(ttwu_count);
 177         P(ttwu_local);
 178
 179         P(bkl_count);
 180
 181 #undef P
 182 #endif
 183         SEQ_printf(m, "  .%-30s: %ld\n", "nr_spread_over",
 184                         cfs_rq->nr_spread_over);
 185 #ifdef CONFIG_FAIR_GROUP_SCHED
 186 #ifdef CONFIG_SMP
 187         SEQ_printf(m, "  .%-30s: %lu\n", "shares", cfs_rq->shares);
 188 #endif
 189 #endif
 190 }
 191
 192 void print_rt_rq(struct seq_file *m, int cpu, struct rt_rq *rt_rq)
 193 {
 194 #if defined(CONFIG_CGROUP_SCHED) && defined(CONFIG_RT_GROUP_SCHED)
 195         char path[128] = "";
 196         struct cgroup *cgroup = NULL;
 197         struct task_group *tg = rt_rq->tg;
 198
 199         if (tg)
 200                 cgroup = tg->css.cgroup;
 201
 202         if (cgroup)
 203                 cgroup_path(cgroup, path, sizeof(path));
 204
 205         SEQ_printf(m, "\nrt_rq[%d]:%s\n", cpu, path);
 206 #else
 207         SEQ_printf(m, "\nrt_rq[%d]:\n", cpu);
 208 #endif
 209
 210
 211 #define P(x) \
 212         SEQ_printf(m, "  .%-30s: %Ld\n", #x, (long long)(rt_rq->x))
 213 #define PN(x) \
 214         SEQ_printf(m, "  .%-30s: %Ld.%06ld\n", #x, SPLIT_NS(rt_rq->x))
 215
 216         P(rt_nr_running);
 217         P(rt_throttled);
 218         PN(rt_time);
 219         PN(rt_runtime);
 220
 221 #undef PN
 222 #undef P
 223 }
 224
 225 static void print_cpu(struct seq_file *m, int cpu)
 226 {
 227         struct rq *rq = &per_cpu(runqueues, cpu);
 228
 229 #ifdef CONFIG_X86
 230         {
 231                 unsigned int freq = cpu_khz ? : 1;
 232
 233                 SEQ_printf(m, "\ncpu#%d, %u.%03u MHz\n",
 234                            cpu, freq / 1000, (freq % 1000));
 235         }
 236 #else
 237         SEQ_printf(m, "\ncpu#%d\n", cpu);
 238 #endif
 239
 240 #define P(x) \
 241         SEQ_printf(m, "  .%-30s: %Ld\n", #x, (long long)(rq->x))
 242 #define PN(x) \
 243         SEQ_printf(m, "  .%-30s: %Ld.%06ld\n", #x, SPLIT_NS(rq->x))
 244
 245         P(nr_running);
 246         SEQ_printf(m, "  .%-30s: %lu\n", "load",
 247                    rq->load.weight);
 248         P(nr_switches);
 249         P(nr_load_updates);
 250         P(nr_uninterruptible);
 251         SEQ_printf(m, "  .%-30s: %lu\n", "jiffies", jiffies);
 252         PN(next_balance);
 253         P(curr->pid);
 254         PN(clock);
 255         P(cpu_load[0]);
 256         P(cpu_load[1]);
 257         P(cpu_load[2]);
 258         P(cpu_load[3]);
 259         P(cpu_load[4]);
 260 #undef P
 261 #undef PN
 262
 263         print_cfs_stats(m, cpu);
 264         print_rt_stats(m, cpu);
 265
 266         print_rq(m, rq, cpu);
 267 }
 268
 269 static int sched_debug_show(struct seq_file *m, void *v)
 270 {
 271         u64 now = ktime_to_ns(ktime_get());
 272         int cpu;
 273
 274         SEQ_printf(m, "Sched Debug Version: v0.07, %s %.*s\n",
 275                 init_utsname()->release,
 276                 (int)strcspn(init_utsname()->version, " "),
 277                 init_utsname()->version);
 278
 279         SEQ_printf(m, "now at %Lu.%06ld msecs\n", SPLIT_NS(now));
 280
 281 #define P(x) \
 282         SEQ_printf(m, "  .%-40s: %Ld\n", #x, (long long)(x))
 283 #define PN(x) \
 284         SEQ_printf(m, "  .%-40s: %Ld.%06ld\n", #x, SPLIT_NS(x))
 285         PN(sysctl_sched_latency);
 286         PN(sysctl_sched_min_granularity);
 287         PN(sysctl_sched_wakeup_granularity);
 288         PN(sysctl_sched_child_runs_first);
 289         P(sysctl_sched_features);
 290 #undef PN
 291 #undef P
 292
 293         for_each_online_cpu(cpu)
 294                 print_cpu(m, cpu);
 295
 296         SEQ_printf(m, "\n");
 297
 298         return 0;
 299 }
 300
 301 static void sysrq_sched_debug_show(void)
 302 {
 303         sched_debug_show(NULL, NULL);
 304 }
 305
 306 static int sched_debug_open(struct inode *inode, struct file *filp)
 307 {
 308         return single_open(filp, sched_debug_show, NULL);
 309 }
 310
 311 static const struct file_operations sched_debug_fops = {
 312         .open           = sched_debug_open,
 313         .read           = seq_read,
 314         .llseek         = seq_lseek,
 315         .release        = single_release,
 316 };
 317
 318 static int __init init_sched_debug_procfs(void)
 319 {
 320         struct proc_dir_entry *pe;
 321
 322         pe = proc_create("sched_debug", 0644, NULL, &sched_debug_fops);
 323         if (!pe)
 324                 return -ENOMEM;
 325         return 0;
 326 }
 327
 328 __initcall(init_sched_debug_procfs);
 329
 330 void proc_sched_show_task(struct task_struct *p, struct seq_file *m)
 331 {
 332         unsigned long nr_switches;
 333         unsigned long flags;
 334         int num_threads = 1;
 335
 336         if (lock_task_sighand(p, &flags)) {
 337                 num_threads = atomic_read(&p->signal->count);
 338                 unlock_task_sighand(p, &flags);
 339         }
 340
 341         SEQ_printf(m, "%s (%d, #threads: %d)\n", p->comm, p->pid, num_threads);
 342         SEQ_printf(m,
 343                 "---------------------------------------------------------\n");
 344 #define __P(F) \
 345         SEQ_printf(m, "%-35s:%21Ld\n", #F, (long long)F)
 346 #define P(F) \
 347         SEQ_printf(m, "%-35s:%21Ld\n", #F, (long long)p->F)
 348 #define __PN(F) \
 349         SEQ_printf(m, "%-35s:%14Ld.%06ld\n", #F, SPLIT_NS((long long)F))
 350 #define PN(F) \
 351         SEQ_printf(m, "%-35s:%14Ld.%06ld\n", #F, SPLIT_NS((long long)p->F))
 352
 353         PN(se.exec_start);
 354         PN(se.vruntime);
 355         PN(se.sum_exec_runtime);
 356         PN(se.avg_overlap);
 357
 358         nr_switches = p->nvcsw + p->nivcsw;
 359
 360 #ifdef CONFIG_SCHEDSTATS
 361         PN(se.wait_start);
 362         PN(se.sleep_start);
 363         PN(se.block_start);
 364         PN(se.sleep_max);
 365         PN(se.block_max);
 366         PN(se.exec_max);
 367         PN(se.slice_max);
 368         PN(se.wait_max);
 369         PN(se.wait_sum);
 370         P(se.wait_count);
 371         P(sched_info.bkl_count);
 372         P(se.nr_migrations);
 373         P(se.nr_migrations_cold);
 374         P(se.nr_failed_migrations_affine);
 375         P(se.nr_failed_migrations_running);
 376         P(se.nr_failed_migrations_hot);
 377         P(se.nr_forced_migrations);
 378         P(se.nr_forced2_migrations);
 379         P(se.nr_wakeups);
 380         P(se.nr_wakeups_sync);
 381         P(se.nr_wakeups_migrate);
 382         P(se.nr_wakeups_local);
 383         P(se.nr_wakeups_remote);
 384         P(se.nr_wakeups_affine);
 385         P(se.nr_wakeups_affine_attempts);
 386         P(se.nr_wakeups_passive);
 387         P(se.nr_wakeups_idle);
 388
 389         {
 390                 u64 avg_atom, avg_per_cpu;
 391
 392                 avg_atom = p->se.sum_exec_runtime;
 393                 if (nr_switches)
 394                         do_div(avg_atom, nr_switches);
 395                 else
 396                         avg_atom = -1LL;
 397
 398                 avg_per_cpu = p->se.sum_exec_runtime;
 399                 if (p->se.nr_migrations) {
 400                         avg_per_cpu = div64_u64(avg_per_cpu,
 401                                                 p->se.nr_migrations);
 402                 } else {
 403                         avg_per_cpu = -1LL;
 404                 }
 405
 406                 __PN(avg_atom);
 407                 __PN(avg_per_cpu);
 408         }
 409 #endif
 410         __P(nr_switches);
 411         SEQ_printf(m, "%-35s:%21Ld\n",
 412                    "nr_voluntary_switches", (long long)p->nvcsw);
 413         SEQ_printf(m, "%-35s:%21Ld\n",
 414                    "nr_involuntary_switches", (long long)p->nivcsw);
 415
 416         P(se.load.weight);
 417         P(policy);
 418         P(prio);
 419 #undef PN
 420 #undef __PN
 421 #undef P
 422 #undef __P
 423
 424         {
 425                 u64 t0, t1;
 426
 427                 t0 = sched_clock();
 428                 t1 = sched_clock();
 429                 SEQ_printf(m, "%-35s:%21Ld\n",
 430                            "clock-delta", (long long)(t1-t0));
 431         }
 432 }
 433
 434 void proc_sched_set_task(struct task_struct *p)
 435 {
 436 #ifdef CONFIG_SCHEDSTATS
 437         p->se.wait_max                          = 0;
 438         p->se.wait_sum                          = 0;
 439         p->se.wait_count                        = 0;
 440         p->se.sleep_max                         = 0;
 441         p->se.sum_sleep_runtime                 = 0;
 442         p->se.block_max                         = 0;
 443         p->se.exec_max                          = 0;
 444         p->se.slice_max                         = 0;
 445         p->se.nr_migrations                     = 0;
 446         p->se.nr_migrations_cold                = 0;
 447         p->se.nr_failed_migrations_affine       = 0;
 448         p->se.nr_failed_migrations_running      = 0;
 449         p->se.nr_failed_migrations_hot          = 0;
 450         p->se.nr_forced_migrations              = 0;
 451         p->se.nr_forced2_migrations             = 0;
 452         p->se.nr_wakeups                        = 0;
 453         p->se.nr_wakeups_sync                   = 0;
 454         p->se.nr_wakeups_migrate                = 0;
 455         p->se.nr_wakeups_local                  = 0;
 456         p->se.nr_wakeups_remote                 = 0;
 457         p->se.nr_wakeups_affine                 = 0;
 458         p->se.nr_wakeups_affine_attempts        = 0;
 459         p->se.nr_wakeups_passive                = 0;
 460         p->se.nr_wakeups_idle                   = 0;
 461         p->sched_info.bkl_count                 = 0;
 462 #endif
 463         p->se.sum_exec_runtime                  = 0;
 464         p->se.prev_sum_exec_runtime             = 0;
 465         p->nvcsw                                = 0;
 466         p->nivcsw                               = 0;
 467 }