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         PN(idle_clock);
 208         PN(prev_clock_raw);
 209         P(clock_warps);
 210         P(clock_overflows);
 211         P(clock_underflows);
 212         P(clock_deep_idle_events);
 213         PN(clock_max_delta);
 214         P(cpu_load[0]);
 215         P(cpu_load[1]);
 216         P(cpu_load[2]);
 217         P(cpu_load[3]);
 218         P(cpu_load[4]);
 219 #undef P
 220 #undef PN
 221
 222         print_cfs_stats(m, cpu);
 223
 224         print_rq(m, rq, cpu);
 225 }
 226
 227 static int sched_debug_show(struct seq_file *m, void *v)
 228 {
 229         u64 now = ktime_to_ns(ktime_get());
 230         int cpu;
 231
 232         SEQ_printf(m, "Sched Debug Version: v0.07, %s %.*s\n",
 233                 init_utsname()->release,
 234                 (int)strcspn(init_utsname()->version, " "),
 235                 init_utsname()->version);
 236
 237         SEQ_printf(m, "now at %Lu.%06ld msecs\n", SPLIT_NS(now));
 238
 239 #define P(x) \
 240         SEQ_printf(m, "  .%-40s: %Ld\n", #x, (long long)(x))
 241 #define PN(x) \
 242         SEQ_printf(m, "  .%-40s: %Ld.%06ld\n", #x, SPLIT_NS(x))
 243         PN(sysctl_sched_latency);
 244         PN(sysctl_sched_min_granularity);
 245         PN(sysctl_sched_wakeup_granularity);
 246         PN(sysctl_sched_child_runs_first);
 247         P(sysctl_sched_features);
 248 #undef PN
 249 #undef P
 250
 251         for_each_online_cpu(cpu)
 252                 print_cpu(m, cpu);
 253
 254         SEQ_printf(m, "\n");
 255
 256         return 0;
 257 }
 258
 259 static void sysrq_sched_debug_show(void)
 260 {
 261         sched_debug_show(NULL, NULL);
 262 }
 263
 264 static int sched_debug_open(struct inode *inode, struct file *filp)
 265 {
 266         return single_open(filp, sched_debug_show, NULL);
 267 }
 268
 269 static const struct file_operations sched_debug_fops = {
 270         .open           = sched_debug_open,
 271         .read           = seq_read,
 272         .llseek         = seq_lseek,
 273         .release        = single_release,
 274 };
 275
 276 static int __init init_sched_debug_procfs(void)
 277 {
 278         struct proc_dir_entry *pe;
 279
 280         pe = create_proc_entry("sched_debug", 0644, NULL);
 281         if (!pe)
 282                 return -ENOMEM;
 283
 284         pe->proc_fops = &sched_debug_fops;
 285
 286         return 0;
 287 }
 288
 289 __initcall(init_sched_debug_procfs);
 290
 291 void proc_sched_show_task(struct task_struct *p, struct seq_file *m)
 292 {
 293         unsigned long nr_switches;
 294         unsigned long flags;
 295         int num_threads = 1;
 296
 297         rcu_read_lock();
 298         if (lock_task_sighand(p, &flags)) {
 299                 num_threads = atomic_read(&p->signal->count);
 300                 unlock_task_sighand(p, &flags);
 301         }
 302         rcu_read_unlock();
 303
 304         SEQ_printf(m, "%s (%d, #threads: %d)\n", p->comm, p->pid, num_threads);
 305         SEQ_printf(m,
 306                 "---------------------------------------------------------\n");
 307 #define __P(F) \
 308         SEQ_printf(m, "%-35s:%21Ld\n", #F, (long long)F)
 309 #define P(F) \
 310         SEQ_printf(m, "%-35s:%21Ld\n", #F, (long long)p->F)
 311 #define __PN(F) \
 312         SEQ_printf(m, "%-35s:%14Ld.%06ld\n", #F, SPLIT_NS((long long)F))
 313 #define PN(F) \
 314         SEQ_printf(m, "%-35s:%14Ld.%06ld\n", #F, SPLIT_NS((long long)p->F))
 315
 316         PN(se.exec_start);
 317         PN(se.vruntime);
 318         PN(se.sum_exec_runtime);
 319         PN(se.avg_overlap);
 320
 321         nr_switches = p->nvcsw + p->nivcsw;
 322
 323 #ifdef CONFIG_SCHEDSTATS
 324         PN(se.wait_start);
 325         PN(se.sleep_start);
 326         PN(se.block_start);
 327         PN(se.sleep_max);
 328         PN(se.block_max);
 329         PN(se.exec_max);
 330         PN(se.slice_max);
 331         PN(se.wait_max);
 332         PN(se.wait_sum);
 333         P(se.wait_count);
 334         P(sched_info.bkl_count);
 335         P(se.nr_migrations);
 336         P(se.nr_migrations_cold);
 337         P(se.nr_failed_migrations_affine);
 338         P(se.nr_failed_migrations_running);
 339         P(se.nr_failed_migrations_hot);
 340         P(se.nr_forced_migrations);
 341         P(se.nr_forced2_migrations);
 342         P(se.nr_wakeups);
 343         P(se.nr_wakeups_sync);
 344         P(se.nr_wakeups_migrate);
 345         P(se.nr_wakeups_local);
 346         P(se.nr_wakeups_remote);
 347         P(se.nr_wakeups_affine);
 348         P(se.nr_wakeups_affine_attempts);
 349         P(se.nr_wakeups_passive);
 350         P(se.nr_wakeups_idle);
 351
 352         {
 353                 u64 avg_atom, avg_per_cpu;
 354
 355                 avg_atom = p->se.sum_exec_runtime;
 356                 if (nr_switches)
 357                         do_div(avg_atom, nr_switches);
 358                 else
 359                         avg_atom = -1LL;
 360
 361                 avg_per_cpu = p->se.sum_exec_runtime;
 362                 if (p->se.nr_migrations) {
 363                         avg_per_cpu = div64_64(avg_per_cpu,
 364                                                p->se.nr_migrations);
 365                 } else {
 366                         avg_per_cpu = -1LL;
 367                 }
 368
 369                 __PN(avg_atom);
 370                 __PN(avg_per_cpu);
 371         }
 372 #endif
 373         __P(nr_switches);
 374         SEQ_printf(m, "%-35s:%21Ld\n",
 375                    "nr_voluntary_switches", (long long)p->nvcsw);
 376         SEQ_printf(m, "%-35s:%21Ld\n",
 377                    "nr_involuntary_switches", (long long)p->nivcsw);
 378
 379         P(se.load.weight);
 380         P(policy);
 381         P(prio);
 382 #undef PN
 383 #undef __PN
 384 #undef P
 385 #undef __P
 386
 387         {
 388                 u64 t0, t1;
 389
 390                 t0 = sched_clock();
 391                 t1 = sched_clock();
 392                 SEQ_printf(m, "%-35s:%21Ld\n",
 393                            "clock-delta", (long long)(t1-t0));
 394         }
 395 }
 396
 397 void proc_sched_set_task(struct task_struct *p)
 398 {
 399 #ifdef CONFIG_SCHEDSTATS
 400         p->se.wait_max                          = 0;
 401         p->se.wait_sum                          = 0;
 402         p->se.wait_count                        = 0;
 403         p->se.sleep_max                         = 0;
 404         p->se.sum_sleep_runtime                 = 0;
 405         p->se.block_max                         = 0;
 406         p->se.exec_max                          = 0;
 407         p->se.slice_max                         = 0;
 408         p->se.nr_migrations                     = 0;
 409         p->se.nr_migrations_cold                = 0;
 410         p->se.nr_failed_migrations_affine       = 0;
 411         p->se.nr_failed_migrations_running      = 0;
 412         p->se.nr_failed_migrations_hot          = 0;
 413         p->se.nr_forced_migrations              = 0;
 414         p->se.nr_forced2_migrations             = 0;
 415         p->se.nr_wakeups                        = 0;
 416         p->se.nr_wakeups_sync                   = 0;
 417         p->se.nr_wakeups_migrate                = 0;
 418         p->se.nr_wakeups_local                  = 0;
 419         p->se.nr_wakeups_remote                 = 0;
 420         p->se.nr_wakeups_affine                 = 0;
 421         p->se.nr_wakeups_affine_attempts        = 0;
 422         p->se.nr_wakeups_passive                = 0;
 423         p->se.nr_wakeups_idle                   = 0;
 424         p->sched_info.bkl_count                 = 0;
 425 #endif
 426         p->se.sum_exec_runtime                  = 0;
 427         p->se.prev_sum_exec_runtime             = 0;
 428         p->nvcsw                                = 0;
 429         p->nivcsw                               = 0;
 430 }