LXR linux/kernel/sched/stats.c

   1
   2#include <linux/slab.h>
   3#include <linux/fs.h>
   4#include <linux/seq_file.h>
   5#include <linux/proc_fs.h>
   6
   7#include "sched.h"
   8
   9/*
  10 * bump this up when changing the output format or the meaning of an existing
  11 * format, so that tools can adapt (or abort)
  12 */
  13#define SCHEDSTAT_VERSION 15
  14
  15static int show_schedstat(struct seq_file *seq, void *v)
  16{
  17        int cpu;
  18        int mask_len = DIV_ROUND_UP(NR_CPUS, 32) * 9;
  19        char *mask_str = kmalloc(mask_len, GFP_KERNEL);
  20
  21        if (mask_str == NULL)
  22                return -ENOMEM;
  23
  24        seq_printf(seq, "version %d\n", SCHEDSTAT_VERSION);
  25        seq_printf(seq, "timestamp %lu\n", jiffies);
  26        for_each_online_cpu(cpu) {
  27                struct rq *rq = cpu_rq(cpu);
  28#ifdef CONFIG_SMP
  29                struct sched_domain *sd;
  30                int dcount = 0;
  31#endif
  32
  33                /* runqueue-specific stats */
  34                seq_printf(seq,
  35                    "cpu%d %u 0 %u %u %u %u %llu %llu %lu",
  36                    cpu, rq->yld_count,
  37                    rq->sched_count, rq->sched_goidle,
  38                    rq->ttwu_count, rq->ttwu_local,
  39                    rq->rq_cpu_time,
  40                    rq->rq_sched_info.run_delay, rq->rq_sched_info.pcount);
  41
  42                seq_printf(seq, "\n");
  43
  44#ifdef CONFIG_SMP
  45                /* domain-specific stats */
  46                rcu_read_lock();
  47                for_each_domain(cpu, sd) {
  48                        enum cpu_idle_type itype;
  49
  50                        cpumask_scnprintf(mask_str, mask_len,
  51                                          sched_domain_span(sd));
  52                        seq_printf(seq, "domain%d %s", dcount++, mask_str);
  53                        for (itype = CPU_IDLE; itype < CPU_MAX_IDLE_TYPES;
  54                                        itype++) {
  55                                seq_printf(seq, " %u %u %u %u %u %u %u %u",
  56                                    sd->lb_count[itype],
  57                                    sd->lb_balanced[itype],
  58                                    sd->lb_failed[itype],
  59                                    sd->lb_imbalance[itype],
  60                                    sd->lb_gained[itype],
  61                                    sd->lb_hot_gained[itype],
  62                                    sd->lb_nobusyq[itype],
  63                                    sd->lb_nobusyg[itype]);
  64                        }
  65                        seq_printf(seq,
  66                                   " %u %u %u %u %u %u %u %u %u %u %u %u\n",
  67                            sd->alb_count, sd->alb_failed, sd->alb_pushed,
  68                            sd->sbe_count, sd->sbe_balanced, sd->sbe_pushed,
  69                            sd->sbf_count, sd->sbf_balanced, sd->sbf_pushed,
  70                            sd->ttwu_wake_remote, sd->ttwu_move_affine,
  71                            sd->ttwu_move_balance);
  72                }
  73                rcu_read_unlock();
  74#endif
  75        }
  76        kfree(mask_str);
  77        return 0;
  78}
  79
  80static int schedstat_open(struct inode *inode, struct file *file)
  81{
  82        unsigned int size = PAGE_SIZE * (1 + num_online_cpus() / 32);
  83        char *buf = kmalloc(size, GFP_KERNEL);
  84        struct seq_file *m;
  85        int res;
  86
  87        if (!buf)
  88                return -ENOMEM;
  89        res = single_open(file, show_schedstat, NULL);
  90        if (!res) {
  91                m = file->private_data;
  92                m->buf = buf;
  93                m->size = size;
  94        } else
  95                kfree(buf);
  96        return res;
  97}
  98
  99static const struct file_operations proc_schedstat_operations = {
 100        .open    = schedstat_open,
 101        .read    = seq_read,
 102        .llseek  = seq_lseek,
 103        .release = single_release,
 104};
 105
 106static int __init proc_schedstat_init(void)
 107{
 108        proc_create("schedstat", 0, NULL, &proc_schedstat_operations);
 109        return 0;
 110}
 111module_init(proc_schedstat_init);
 112