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 static void
  32 print_task(struct seq_file *m, struct rq *rq, struct task_struct *p)
  33 {
  34         if (rq->curr == p)
  35                 SEQ_printf(m, "R");
  36         else
  37                 SEQ_printf(m, " ");
  38
  39         SEQ_printf(m, "%15s %5d %15Ld %13Ld %13Ld %9Ld %5d ",
  40                 p->comm, p->pid,
  41                 (long long)p->se.fair_key,
  42                 (long long)(p->se.fair_key - rq->cfs.fair_clock),
  43                 (long long)p->se.wait_runtime,
  44                 (long long)(p->nvcsw + p->nivcsw),
  45                 p->prio);
  46 #ifdef CONFIG_SCHEDSTATS
  47         SEQ_printf(m, "%15Ld %15Ld %15Ld %15Ld %15Ld %15Ld\n",
  48                 (long long)p->se.vruntime,
  49                 (long long)p->se.sum_exec_runtime,
  50                 (long long)p->se.sum_wait_runtime,
  51                 (long long)p->se.sum_sleep_runtime,
  52                 (long long)p->se.wait_runtime_overruns,
  53                 (long long)p->se.wait_runtime_underruns);
  54 #else
  55         SEQ_printf(m, "%15Ld %15Ld %15Ld %15Ld %15Ld\n",
  56                 0LL, 0LL, 0LL, 0LL, 0LL);
  57 #endif
  58 }
  59
  60 static void print_rq(struct seq_file *m, struct rq *rq, int rq_cpu)
  61 {
  62         struct task_struct *g, *p;
  63
  64         SEQ_printf(m,
  65         "\nrunnable tasks:\n"
  66         "            task   PID        tree-key         delta       waiting"
  67         "  switches  prio"
  68         "    exec-runtime        sum-exec        sum-wait       sum-sleep"
  69         "    wait-overrun   wait-underrun\n"
  70         "------------------------------------------------------------------"
  71         "--------------------------------"
  72         "------------------------------------------------"
  73         "--------------------------------\n");
  74
  75         read_lock_irq(&tasklist_lock);
  76
  77         do_each_thread(g, p) {
  78                 if (!p->se.on_rq || task_cpu(p) != rq_cpu)
  79                         continue;
  80
  81                 print_task(m, rq, p);
  82         } while_each_thread(g, p);
  83
  84         read_unlock_irq(&tasklist_lock);
  85 }
  86
  87 static void
  88 print_cfs_rq_runtime_sum(struct seq_file *m, int cpu, struct cfs_rq *cfs_rq)
  89 {
  90         s64 wait_runtime_rq_sum = 0;
  91         struct task_struct *p;
  92         struct rb_node *curr;
  93         unsigned long flags;
  94         struct rq *rq = &per_cpu(runqueues, cpu);
  95
  96         spin_lock_irqsave(&rq->lock, flags);
  97         curr = first_fair(cfs_rq);
  98         while (curr) {
  99                 p = rb_entry(curr, struct task_struct, se.run_node);
 100                 wait_runtime_rq_sum += p->se.wait_runtime;
 101
 102                 curr = rb_next(curr);
 103         }
 104         spin_unlock_irqrestore(&rq->lock, flags);
 105
 106         SEQ_printf(m, "  .%-30s: %Ld\n", "wait_runtime_rq_sum",
 107                 (long long)wait_runtime_rq_sum);
 108 }
 109
 110 void print_cfs_rq(struct seq_file *m, int cpu, struct cfs_rq *cfs_rq)
 111 {
 112         s64 MIN_vruntime = -1, min_vruntime, max_vruntime = -1,
 113                 spread, rq0_min_vruntime, spread0;
 114         struct rq *rq = &per_cpu(runqueues, cpu);
 115         struct sched_entity *last;
 116         unsigned long flags;
 117
 118         SEQ_printf(m, "\ncfs_rq\n");
 119
 120 #define P(x) \
 121         SEQ_printf(m, "  .%-30s: %Ld\n", #x, (long long)(cfs_rq->x))
 122
 123         P(fair_clock);
 124         P(exec_clock);
 125
 126         spin_lock_irqsave(&rq->lock, flags);
 127         if (cfs_rq->rb_leftmost)
 128                 MIN_vruntime = (__pick_next_entity(cfs_rq))->vruntime;
 129         last = __pick_last_entity(cfs_rq);
 130         if (last)
 131                 max_vruntime = last->vruntime;
 132         min_vruntime = rq->cfs.min_vruntime;
 133         rq0_min_vruntime = per_cpu(runqueues, 0).cfs.min_vruntime;
 134         spin_unlock_irqrestore(&rq->lock, flags);
 135         SEQ_printf(m, "  .%-30s: %Ld\n", "MIN_vruntime",
 136                         (long long)MIN_vruntime);
 137         SEQ_printf(m, "  .%-30s: %Ld\n", "min_vruntime",
 138                         (long long)min_vruntime);
 139         SEQ_printf(m, "  .%-30s: %Ld\n", "max_vruntime",
 140                         (long long)max_vruntime);
 141         spread = max_vruntime - MIN_vruntime;
 142         SEQ_printf(m, "  .%-30s: %Ld\n", "spread",
 143                         (long long)spread);
 144         spread0 = min_vruntime - rq0_min_vruntime;
 145         SEQ_printf(m, "  .%-30s: %Ld\n", "spread0",
 146                         (long long)spread0);
 147
 148         P(wait_runtime);
 149         P(wait_runtime_overruns);
 150         P(wait_runtime_underruns);
 151         P(sleeper_bonus);
 152 #undef P
 153
 154         print_cfs_rq_runtime_sum(m, cpu, cfs_rq);
 155 }
 156
 157 static void print_cpu(struct seq_file *m, int cpu)
 158 {
 159         struct rq *rq = &per_cpu(runqueues, cpu);
 160
 161 #ifdef CONFIG_X86
 162         {
 163                 unsigned int freq = cpu_khz ? : 1;
 164
 165                 SEQ_printf(m, "\ncpu#%d, %u.%03u MHz\n",
 166                            cpu, freq / 1000, (freq % 1000));
 167         }
 168 #else
 169         SEQ_printf(m, "\ncpu#%d\n", cpu);
 170 #endif
 171
 172 #define P(x) \
 173         SEQ_printf(m, "  .%-30s: %Ld\n", #x, (long long)(rq->x))
 174
 175         P(nr_running);
 176         SEQ_printf(m, "  .%-30s: %lu\n", "load",
 177                    rq->ls.load.weight);
 178         P(nr_switches);
 179         P(nr_load_updates);
 180         P(nr_uninterruptible);
 181         SEQ_printf(m, "  .%-30s: %lu\n", "jiffies", jiffies);
 182         P(next_balance);
 183         P(curr->pid);
 184         P(clock);
 185         P(idle_clock);
 186         P(prev_clock_raw);
 187         P(clock_warps);
 188         P(clock_overflows);
 189         P(clock_deep_idle_events);
 190         P(clock_max_delta);
 191         P(cpu_load[0]);
 192         P(cpu_load[1]);
 193         P(cpu_load[2]);
 194         P(cpu_load[3]);
 195         P(cpu_load[4]);
 196 #undef P
 197
 198         print_cfs_stats(m, cpu);
 199
 200         print_rq(m, rq, cpu);
 201 }
 202
 203 static int sched_debug_show(struct seq_file *m, void *v)
 204 {
 205         u64 now = ktime_to_ns(ktime_get());
 206         int cpu;
 207
 208         SEQ_printf(m, "Sched Debug Version: v0.05-v20, %s %.*s\n",
 209                 init_utsname()->release,
 210                 (int)strcspn(init_utsname()->version, " "),
 211                 init_utsname()->version);
 212
 213         SEQ_printf(m, "now at %Lu nsecs\n", (unsigned long long)now);
 214
 215         for_each_online_cpu(cpu)
 216                 print_cpu(m, cpu);
 217
 218         SEQ_printf(m, "\n");
 219
 220         return 0;
 221 }
 222
 223 static void sysrq_sched_debug_show(void)
 224 {
 225         sched_debug_show(NULL, NULL);
 226 }
 227
 228 static int sched_debug_open(struct inode *inode, struct file *filp)
 229 {
 230         return single_open(filp, sched_debug_show, NULL);
 231 }
 232
 233 static struct file_operations sched_debug_fops = {
 234         .open           = sched_debug_open,
 235         .read           = seq_read,
 236         .llseek         = seq_lseek,
 237         .release        = single_release,
 238 };
 239
 240 static int __init init_sched_debug_procfs(void)
 241 {
 242         struct proc_dir_entry *pe;
 243
 244         pe = create_proc_entry("sched_debug", 0644, NULL);
 245         if (!pe)
 246                 return -ENOMEM;
 247
 248         pe->proc_fops = &sched_debug_fops;
 249
 250         return 0;
 251 }
 252
 253 __initcall(init_sched_debug_procfs);
 254
 255 void proc_sched_show_task(struct task_struct *p, struct seq_file *m)
 256 {
 257         unsigned long flags;
 258         int num_threads = 1;
 259
 260         rcu_read_lock();
 261         if (lock_task_sighand(p, &flags)) {
 262                 num_threads = atomic_read(&p->signal->count);
 263                 unlock_task_sighand(p, &flags);
 264         }
 265         rcu_read_unlock();
 266
 267         SEQ_printf(m, "%s (%d, #threads: %d)\n", p->comm, p->pid, num_threads);
 268         SEQ_printf(m, "----------------------------------------------\n");
 269 #define P(F) \
 270         SEQ_printf(m, "%-25s:%20Ld\n", #F, (long long)p->F)
 271
 272         P(se.wait_runtime);
 273         P(se.wait_start_fair);
 274         P(se.exec_start);
 275         P(se.sleep_start_fair);
 276         P(se.vruntime);
 277         P(se.sum_exec_runtime);
 278
 279 #ifdef CONFIG_SCHEDSTATS
 280         P(se.wait_start);
 281         P(se.sleep_start);
 282         P(se.block_start);
 283         P(se.sleep_max);
 284         P(se.block_max);
 285         P(se.exec_max);
 286         P(se.slice_max);
 287         P(se.wait_max);
 288         P(se.wait_runtime_overruns);
 289         P(se.wait_runtime_underruns);
 290         P(se.sum_wait_runtime);
 291 #endif
 292         SEQ_printf(m, "%-25s:%20Ld\n",
 293                    "nr_switches", (long long)(p->nvcsw + p->nivcsw));
 294         P(se.load.weight);
 295         P(policy);
 296         P(prio);
 297 #undef P
 298
 299         {
 300                 u64 t0, t1;
 301
 302                 t0 = sched_clock();
 303                 t1 = sched_clock();
 304                 SEQ_printf(m, "%-25s:%20Ld\n",
 305                            "clock-delta", (long long)(t1-t0));
 306         }
 307 }
 308
 309 void proc_sched_set_task(struct task_struct *p)
 310 {
 311 #ifdef CONFIG_SCHEDSTATS
 312         p->se.sleep_max                 = 0;
 313         p->se.block_max                 = 0;
 314         p->se.exec_max                  = 0;
 315         p->se.slice_max                 = 0;
 316         p->se.wait_max                  = 0;
 317         p->se.wait_runtime_overruns     = 0;
 318         p->se.wait_runtime_underruns    = 0;
 319 #endif
 320         p->se.sum_exec_runtime          = 0;
 321         p->se.prev_sum_exec_runtime     = 0;
 322 }