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