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