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 u64 get_idle_time(int cpu)
  26 {
  27         u64 idle, idle_time = get_cpu_idle_time_us(cpu, NULL);
  28
  29         if (idle_time == -1ULL) {
  30                 /* !NO_HZ so we can rely on cpustat.idle */
  31                 idle = kcpustat_cpu(cpu).cpustat[CPUTIME_IDLE];
  32                 idle += arch_idle_time(cpu);
  33         } else
  34                 idle = usecs_to_cputime64(idle_time);
  35
  36         return idle;
  37 }
  38
  39 static u64 get_iowait_time(int cpu)
  40 {
  41         u64 iowait, iowait_time = get_cpu_iowait_time_us(cpu, NULL);
  42
  43         if (iowait_time == -1ULL)
  44                 /* !NO_HZ so we can rely on cpustat.iowait */
  45                 iowait = kcpustat_cpu(cpu).cpustat[CPUTIME_IOWAIT];
  46         else
  47                 iowait = usecs_to_cputime64(iowait_time);
  48
  49         return iowait;
  50 }
  51
  52 static int show_stat(struct seq_file *p, void *v)
  53 {
  54         int i, j;
  55         unsigned long jif;
  56         u64 user, nice, system, idle, iowait, irq, softirq, steal;
  57         u64 guest, guest_nice;
  58         u64 sum = 0;
  59         u64 sum_softirq = 0;
  60         unsigned int per_softirq_sums[NR_SOFTIRQS] = {0};
  61         struct timespec boottime;
  62
  63         user = nice = system = idle = iowait =
  64                 irq = softirq = steal = 0;
  65         guest = guest_nice = 0;
  66         getboottime(&boottime);
  67         jif = boottime.tv_sec;
  68
  69         for_each_possible_cpu(i) {
  70                 user += kcpustat_cpu(i).cpustat[CPUTIME_USER];
  71                 nice += kcpustat_cpu(i).cpustat[CPUTIME_NICE];
  72                 system += kcpustat_cpu(i).cpustat[CPUTIME_SYSTEM];
  73                 idle += get_idle_time(i);
  74                 iowait += get_iowait_time(i);
  75                 irq += kcpustat_cpu(i).cpustat[CPUTIME_IRQ];
  76                 softirq += kcpustat_cpu(i).cpustat[CPUTIME_SOFTIRQ];
  77                 steal += kcpustat_cpu(i).cpustat[CPUTIME_STEAL];
  78                 guest += kcpustat_cpu(i).cpustat[CPUTIME_GUEST];
  79                 guest_nice += kcpustat_cpu(i).cpustat[CPUTIME_GUEST_NICE];
  80                 sum += kstat_cpu_irqs_sum(i);
  81                 sum += arch_irq_stat_cpu(i);
  82
  83                 for (j = 0; j < NR_SOFTIRQS; j++) {
  84                         unsigned int softirq_stat = kstat_softirqs_cpu(j, i);
  85
  86                         per_softirq_sums[j] += softirq_stat;
  87                         sum_softirq += softirq_stat;
  88                 }
  89         }
  90         sum += arch_irq_stat();
  91
  92         seq_printf(p, "cpu  %llu %llu %llu %llu %llu %llu %llu %llu %llu "
  93                 "%llu\n",
  94                 (unsigned long long)cputime64_to_clock_t(user),
  95                 (unsigned long long)cputime64_to_clock_t(nice),
  96                 (unsigned long long)cputime64_to_clock_t(system),
  97                 (unsigned long long)cputime64_to_clock_t(idle),
  98                 (unsigned long long)cputime64_to_clock_t(iowait),
  99                 (unsigned long long)cputime64_to_clock_t(irq),
 100                 (unsigned long long)cputime64_to_clock_t(softirq),
 101                 (unsigned long long)cputime64_to_clock_t(steal),
 102                 (unsigned long long)cputime64_to_clock_t(guest),
 103                 (unsigned long long)cputime64_to_clock_t(guest_nice));
 104         for_each_online_cpu(i) {
 105                 /* Copy values here to work around gcc-2.95.3, gcc-2.96 */
 106                 user = kcpustat_cpu(i).cpustat[CPUTIME_USER];
 107                 nice = kcpustat_cpu(i).cpustat[CPUTIME_NICE];
 108                 system = kcpustat_cpu(i).cpustat[CPUTIME_SYSTEM];
 109                 idle = get_idle_time(i);
 110                 iowait = get_iowait_time(i);
 111                 irq = kcpustat_cpu(i).cpustat[CPUTIME_IRQ];
 112                 softirq = kcpustat_cpu(i).cpustat[CPUTIME_SOFTIRQ];
 113                 steal = kcpustat_cpu(i).cpustat[CPUTIME_STEAL];
 114                 guest = kcpustat_cpu(i).cpustat[CPUTIME_GUEST];
 115                 guest_nice = kcpustat_cpu(i).cpustat[CPUTIME_GUEST_NICE];
 116                 seq_printf(p,
 117                         "cpu%d %llu %llu %llu %llu %llu %llu %llu %llu %llu "
 118                         "%llu\n",
 119                         i,
 120                         (unsigned long long)cputime64_to_clock_t(user),
 121                         (unsigned long long)cputime64_to_clock_t(nice),
 122                         (unsigned long long)cputime64_to_clock_t(system),
 123                         (unsigned long long)cputime64_to_clock_t(idle),
 124                         (unsigned long long)cputime64_to_clock_t(iowait),
 125                         (unsigned long long)cputime64_to_clock_t(irq),
 126                         (unsigned long long)cputime64_to_clock_t(softirq),
 127                         (unsigned long long)cputime64_to_clock_t(steal),
 128                         (unsigned long long)cputime64_to_clock_t(guest),
 129                         (unsigned long long)cputime64_to_clock_t(guest_nice));
 130         }
 131         seq_printf(p, "intr %llu", (unsigned long long)sum);
 132
 133         /* sum again ? it could be updated? */
 134         for_each_irq_nr(j)
 135                 seq_printf(p, " %u", kstat_irqs(j));
 136
 137         seq_printf(p,
 138                 "\nctxt %llu\n"
 139                 "btime %lu\n"
 140                 "processes %lu\n"
 141                 "procs_running %lu\n"
 142                 "procs_blocked %lu\n",
 143                 nr_context_switches(),
 144                 (unsigned long)jif,
 145                 total_forks,
 146                 nr_running(),
 147                 nr_iowait());
 148
 149         seq_printf(p, "softirq %llu", (unsigned long long)sum_softirq);
 150
 151         for (i = 0; i < NR_SOFTIRQS; i++)
 152                 seq_printf(p, " %u", per_softirq_sums[i]);
 153         seq_putc(p, '\n');
 154
 155         return 0;
 156 }
 157
 158 static int stat_open(struct inode *inode, struct file *file)
 159 {
 160         unsigned size = 4096 * (1 + num_possible_cpus() / 32);
 161         char *buf;
 162         struct seq_file *m;
 163         int res;
 164
 165         /* don't ask for more than the kmalloc() max size */
 166         if (size > KMALLOC_MAX_SIZE)
 167                 size = KMALLOC_MAX_SIZE;
 168         buf = kmalloc(size, GFP_KERNEL);
 169         if (!buf)
 170                 return -ENOMEM;
 171
 172         res = single_open(file, show_stat, NULL);
 173         if (!res) {
 174                 m = file->private_data;
 175                 m->buf = buf;
 176                 m->size = size;
 177         } else
 178                 kfree(buf);
 179         return res;
 180 }
 181
 182 static const struct file_operations proc_stat_operations = {
 183         .open           = stat_open,
 184         .read           = seq_read,
 185         .llseek         = seq_lseek,
 186         .release        = single_release,
 187 };
 188
 189 static int __init proc_stat_init(void)
 190 {
 191         proc_create("stat", 0, NULL, &proc_stat_operations);
 192         return 0;
 193 }
 194 module_init(proc_stat_init);