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 = -1ULL;
  28         cputime64_t idle;
  29
  30         if (cpu_online(cpu))
  31                 idle_time = get_cpu_idle_time_us(cpu, NULL);
  32
  33         if (idle_time == -1ULL) {
  34                 /* !NO_HZ or cpu offline so we can rely on cpustat.idle */
  35                 idle = kstat_cpu(cpu).cpustat.idle;
  36                 idle = cputime64_add(idle, arch_idle_time(cpu));
  37         } else
  38                 idle = usecs_to_cputime64(idle_time);
  39
  40         return idle;
  41 }
  42
  43 static cputime64_t get_iowait_time(int cpu)
  44 {
  45         u64 iowait_time = -1ULL;
  46         cputime64_t iowait;
  47
  48         if (cpu_online(cpu))
  49                 iowait_time = get_cpu_iowait_time_us(cpu, NULL);
  50
  51         if (iowait_time == -1ULL)
  52                 /* !NO_HZ or cpu offline so we can rely on cpustat.iowait */
  53                 iowait = kstat_cpu(cpu).cpustat.iowait;
  54         else
  55                 iowait = usecs_to_cputime64(iowait_time);
  56
  57         return iowait;
  58 }
  59
  60 static int show_stat(struct seq_file *p, void *v)
  61 {
  62         int i, j;
  63         unsigned long jif;
  64         cputime64_t user, nice, system, idle, iowait, irq, softirq, steal;
  65         cputime64_t guest, guest_nice;
  66         u64 sum = 0;
  67         u64 sum_softirq = 0;
  68         unsigned int per_softirq_sums[NR_SOFTIRQS] = {0};
  69         struct timespec boottime;
  70
  71         user = nice = system = idle = iowait =
  72                 irq = softirq = steal = cputime64_zero;
  73         guest = guest_nice = cputime64_zero;
  74         getboottime(&boottime);
  75         jif = boottime.tv_sec;
  76
  77         for_each_possible_cpu(i) {
  78                 user = cputime64_add(user, kstat_cpu(i).cpustat.user);
  79                 nice = cputime64_add(nice, kstat_cpu(i).cpustat.nice);
  80                 system = cputime64_add(system, kstat_cpu(i).cpustat.system);
  81                 idle = cputime64_add(idle, get_idle_time(i));
  82                 iowait = cputime64_add(iowait, get_iowait_time(i));
  83                 irq = cputime64_add(irq, kstat_cpu(i).cpustat.irq);
  84                 softirq = cputime64_add(softirq, kstat_cpu(i).cpustat.softirq);
  85                 steal = cputime64_add(steal, kstat_cpu(i).cpustat.steal);
  86                 guest = cputime64_add(guest, kstat_cpu(i).cpustat.guest);
  87                 guest_nice = cputime64_add(guest_nice,
  88                         kstat_cpu(i).cpustat.guest_nice);
  89                 sum += kstat_cpu_irqs_sum(i);
  90                 sum += arch_irq_stat_cpu(i);
  91
  92                 for (j = 0; j < NR_SOFTIRQS; j++) {
  93                         unsigned int softirq_stat = kstat_softirqs_cpu(j, i);
  94
  95                         per_softirq_sums[j] += softirq_stat;
  96                         sum_softirq += softirq_stat;
  97                 }
  98         }
  99         sum += arch_irq_stat();
 100
 101         seq_printf(p, "cpu  %llu %llu %llu %llu %llu %llu %llu %llu %llu "
 102                 "%llu\n",
 103                 (unsigned long long)cputime64_to_clock_t(user),
 104                 (unsigned long long)cputime64_to_clock_t(nice),
 105                 (unsigned long long)cputime64_to_clock_t(system),
 106                 (unsigned long long)cputime64_to_clock_t(idle),
 107                 (unsigned long long)cputime64_to_clock_t(iowait),
 108                 (unsigned long long)cputime64_to_clock_t(irq),
 109                 (unsigned long long)cputime64_to_clock_t(softirq),
 110                 (unsigned long long)cputime64_to_clock_t(steal),
 111                 (unsigned long long)cputime64_to_clock_t(guest),
 112                 (unsigned long long)cputime64_to_clock_t(guest_nice));
 113         for_each_online_cpu(i) {
 114                 /* Copy values here to work around gcc-2.95.3, gcc-2.96 */
 115                 user = kstat_cpu(i).cpustat.user;
 116                 nice = kstat_cpu(i).cpustat.nice;
 117                 system = kstat_cpu(i).cpustat.system;
 118                 idle = get_idle_time(i);
 119                 iowait = get_iowait_time(i);
 120                 irq = kstat_cpu(i).cpustat.irq;
 121                 softirq = kstat_cpu(i).cpustat.softirq;
 122                 steal = kstat_cpu(i).cpustat.steal;
 123                 guest = kstat_cpu(i).cpustat.guest;
 124                 guest_nice = kstat_cpu(i).cpustat.guest_nice;
 125                 seq_printf(p,
 126                         "cpu%d %llu %llu %llu %llu %llu %llu %llu %llu %llu "
 127                         "%llu\n",
 128                         i,
 129                         (unsigned long long)cputime64_to_clock_t(user),
 130                         (unsigned long long)cputime64_to_clock_t(nice),
 131                         (unsigned long long)cputime64_to_clock_t(system),
 132                         (unsigned long long)cputime64_to_clock_t(idle),
 133                         (unsigned long long)cputime64_to_clock_t(iowait),
 134                         (unsigned long long)cputime64_to_clock_t(irq),
 135                         (unsigned long long)cputime64_to_clock_t(softirq),
 136                         (unsigned long long)cputime64_to_clock_t(steal),
 137                         (unsigned long long)cputime64_to_clock_t(guest),
 138                         (unsigned long long)cputime64_to_clock_t(guest_nice));
 139         }
 140         seq_printf(p, "intr %llu", (unsigned long long)sum);
 141
 142         /* sum again ? it could be updated? */
 143         for_each_irq_nr(j)
 144                 seq_printf(p, " %u", kstat_irqs_usr(j));
 145
 146         seq_printf(p,
 147                 "\nctxt %llu\n"
 148                 "btime %lu\n"
 149                 "processes %lu\n"
 150                 "procs_running %lu\n"
 151                 "procs_blocked %lu\n",
 152                 nr_context_switches(),
 153                 (unsigned long)jif,
 154                 total_forks,
 155                 nr_running(),
 156                 nr_iowait());
 157
 158         seq_printf(p, "softirq %llu", (unsigned long long)sum_softirq);
 159
 160         for (i = 0; i < NR_SOFTIRQS; i++)
 161                 seq_printf(p, " %u", per_softirq_sums[i]);
 162         seq_putc(p, '\n');
 163
 164         return 0;
 165 }
 166
 167 static int stat_open(struct inode *inode, struct file *file)
 168 {
 169         unsigned size = 4096 * (1 + num_possible_cpus() / 32);
 170         char *buf;
 171         struct seq_file *m;
 172         int res;
 173
 174         /* don't ask for more than the kmalloc() max size */
 175         if (size > KMALLOC_MAX_SIZE)
 176                 size = KMALLOC_MAX_SIZE;
 177         buf = kmalloc(size, GFP_KERNEL);
 178         if (!buf)
 179                 return -ENOMEM;
 180
 181         res = single_open(file, show_stat, NULL);
 182         if (!res) {
 183                 m = file->private_data;
 184                 m->buf = buf;
 185                 m->size = size;
 186         } else
 187                 kfree(buf);
 188         return res;
 189 }
 190
 191 static const struct file_operations proc_stat_operations = {
 192         .open           = stat_open,
 193         .read           = seq_read,
 194         .llseek         = seq_lseek,
 195         .release        = single_release,
 196 };
 197
 198 static int __init proc_stat_init(void)
 199 {
 200         proc_create("stat", 0, NULL, &proc_stat_operations);
 201         return 0;
 202 }
 203 module_init(proc_stat_init);