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