fs/proc/stat.c

   1 #include <linux/cpumask.h>
   2 #include <linux/fs.h>
   3 #include <linux/init.h>
   4 #include <linux/interrupt.h>
   5 #include <linux/kernel_stat.h>
   6 #include <linux/proc_fs.h>
   7 #include <linux/sched.h>
   8 #include <linux/seq_file.h>
   9 #include <linux/slab.h>
  10 #include <linux/time.h>
  11 #include <linux/irqnr.h>
  12 #include <asm/cputime.h>
  13 #include <linux/tick.h>
  14
  15 #ifndef arch_irq_stat_cpu
  16 #define arch_irq_stat_cpu(cpu) 0
  17 #endif
  18 #ifndef arch_irq_stat
  19 #define arch_irq_stat() 0
  20 #endif
  21 #ifndef arch_idle_time
  22 #define arch_idle_time(cpu) 0
  23 #endif
  24
  25 static cputime64_t get_idle_time(int cpu)
  26 {
  27         u64 idle_time = get_cpu_idle_time_us(cpu, NULL);
  28         cputime64_t idle;
  29
  30         if (idle_time == -1ULL) {
  31                 /* !NO_HZ so we can rely on cpustat.idle */
  32                 idle = kstat_cpu(cpu).cpustat.idle;
  33                 idle = cputime64_add(idle, arch_idle_time(cpu));
  34         } else
  35                 idle = usecs_to_cputime(idle_time);
  36
  37         return idle;
  38 }
  39
  40 static cputime64_t get_iowait_time(int cpu)
  41 {
  42         u64 iowait_time = get_cpu_iowait_time_us(cpu, NULL);
  43         cputime64_t iowait;
  44
  45         if (iowait_time == -1ULL)
  46                 /* !NO_HZ so we can rely on cpustat.iowait */
  47                 iowait = kstat_cpu(cpu).cpustat.iowait;
  48         else
  49                 iowait = usecs_to_cputime(iowait_time);
  50
  51         return iowait;
  52 }
  53
  54 static int show_stat(struct seq_file *p, void *v)
  55 {
  56         int i, j;
  57         unsigned long jif;
  58         cputime64_t user, nice, system, idle, iowait, irq, softirq, steal;
  59         cputime64_t guest, guest_nice;
  60         u64 sum = 0;
  61         u64 sum_softirq = 0;
  62         unsigned int per_softirq_sums[NR_SOFTIRQS] = {0};
  63         struct timespec boottime;
  64
  65         user = nice = system = idle = iowait =
  66                 irq = softirq = steal = cputime64_zero;
  67         guest = guest_nice = cputime64_zero;
  68         getboottime(&boottime);
  69         jif = boottime.tv_sec;
  70
  71         for_each_possible_cpu(i) {
  72                 user = cputime64_add(user, kstat_cpu(i).cpustat.user);
  73                 nice = cputime64_add(nice, kstat_cpu(i).cpustat.nice);
  74                 system = cputime64_add(system, kstat_cpu(i).cpustat.system);
  75                 idle = cputime64_add(idle, get_idle_time(i));
  76                 iowait = cputime64_add(iowait, get_iowait_time(i));
  77                 irq = cputime64_add(irq, kstat_cpu(i).cpustat.irq);
  78                 softirq = cputime64_add(softirq, kstat_cpu(i).cpustat.softirq);
  79                 steal = cputime64_add(steal, kstat_cpu(i).cpustat.steal);
  80                 guest = cputime64_add(guest, kstat_cpu(i).cpustat.guest);
  81                 guest_nice = cputime64_add(guest_nice,
  82                         kstat_cpu(i).cpustat.guest_nice);
  83                 sum += kstat_cpu_irqs_sum(i);
  84                 sum += arch_irq_stat_cpu(i);
  85
  86                 for (j = 0; j < NR_SOFTIRQS; j++) {
  87                         unsigned int softirq_stat = kstat_softirqs_cpu(j, i);
  88
  89                         per_softirq_sums[j] += softirq_stat;
  90                         sum_softirq += softirq_stat;
  91                 }
  92         }
  93         sum += arch_irq_stat();
  94
  95         seq_printf(p, "cpu  %llu %llu %llu %llu %llu %llu %llu %llu %llu "
  96                 "%llu\n",
  97                 (unsigned long long)cputime64_to_clock_t(user),
  98                 (unsigned long long)cputime64_to_clock_t(nice),
  99                 (unsigned long long)cputime64_to_clock_t(system),
 100                 (unsigned long long)cputime64_to_clock_t(idle),
 101                 (unsigned long long)cputime64_to_clock_t(iowait),
 102                 (unsigned long long)cputime64_to_clock_t(irq),
 103                 (unsigned long long)cputime64_to_clock_t(softirq),
 104                 (unsigned long long)cputime64_to_clock_t(steal),
 105                 (unsigned long long)cputime64_to_clock_t(guest),
 106                 (unsigned long long)cputime64_to_clock_t(guest_nice));
 107         for_each_online_cpu(i) {
 108                 /* Copy values here to work around gcc-2.95.3, gcc-2.96 */
 109                 user = kstat_cpu(i).cpustat.user;
 110                 nice = kstat_cpu(i).cpustat.nice;
 111                 system = kstat_cpu(i).cpustat.system;
 112                 idle = get_idle_time(i);
 113                 iowait = get_iowait_time(i);
 114                 irq = kstat_cpu(i).cpustat.irq;
 115                 softirq = kstat_cpu(i).cpustat.softirq;
 116                 steal = kstat_cpu(i).cpustat.steal;
 117                 guest = kstat_cpu(i).cpustat.guest;
 118                 guest_nice = kstat_cpu(i).cpustat.guest_nice;
 119                 seq_printf(p,
 120                         "cpu%d %llu %llu %llu %llu %llu %llu %llu %llu %llu "
 121                         "%llu\n",
 122                         i,
 123                         (unsigned long long)cputime64_to_clock_t(user),
 124                         (unsigned long long)cputime64_to_clock_t(nice),
 125                         (unsigned long long)cputime64_to_clock_t(system),
 126                         (unsigned long long)cputime64_to_clock_t(idle),
 127                         (unsigned long long)cputime64_to_clock_t(iowait),
 128                         (unsigned long long)cputime64_to_clock_t(irq),
 129                         (unsigned long long)cputime64_to_clock_t(softirq),
 130                         (unsigned long long)cputime64_to_clock_t(steal),
 131                         (unsigned long long)cputime64_to_clock_t(guest),
 132                         (unsigned long long)cputime64_to_clock_t(guest_nice));
 133         }
 134         seq_printf(p, "intr %llu", (unsigned long long)sum);
 135
 136         /* sum again ? it could be updated? */
 137         for_each_irq_nr(j)
 138                 seq_printf(p, " %u", kstat_irqs(j));
 139
 140         seq_printf(p,
 141                 "\nctxt %llu\n"
 142                 "btime %lu\n"
 143                 "processes %lu\n"
 144                 "procs_running %lu\n"
 145                 "procs_blocked %lu\n",
 146                 nr_context_switches(),
 147                 (unsigned long)jif,
 148                 total_forks,
 149                 nr_running(),
 150                 nr_iowait());
 151
 152         seq_printf(p, "softirq %llu", (unsigned long long)sum_softirq);
 153
 154         for (i = 0; i < NR_SOFTIRQS; i++)
 155                 seq_printf(p, " %u", per_softirq_sums[i]);
 156         seq_putc(p, '\n');
 157
 158         return 0;
 159 }
 160
 161 static int stat_open(struct inode *inode, struct file *file)
 162 {
 163         unsigned size = 4096 * (1 + num_possible_cpus() / 32);
 164         char *buf;
 165         struct seq_file *m;
 166         int res;
 167
 168         /* don't ask for more than the kmalloc() max size */
 169         if (size > KMALLOC_MAX_SIZE)
 170                 size = KMALLOC_MAX_SIZE;
 171         buf = kmalloc(size, GFP_KERNEL);
 172         if (!buf)
 173                 return -ENOMEM;
 174
 175         res = single_open(file, show_stat, NULL);
 176         if (!res) {
 177                 m = file->private_data;
 178                 m->buf = buf;
 179                 m->size = size;
 180         } else
 181                 kfree(buf);
 182         return res;
 183 }
 184
 185 static const struct file_operations proc_stat_operations = {
 186         .open           = stat_open,
 187         .read           = seq_read,
 188         .llseek         = seq_lseek,
 189         .release        = single_release,
 190 };
 191
 192 static int __init proc_stat_init(void)
 193 {
 194         proc_create("stat", 0, NULL, &proc_stat_operations);
 195         return 0;
 196 }
 197 module_init(proc_stat_init);