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
  81                 for (j = 0; j < NR_SOFTIRQS; j++) {
  82                         unsigned int softirq_stat = kstat_softirqs_cpu(j, i);
  83
  84                         per_softirq_sums[j] += softirq_stat;
  85                         sum_softirq += softirq_stat;
  86                 }
  87         }
  88         sum += arch_irq_stat();
  89
  90         seq_printf(p, "cpu  %llu %llu %llu %llu %llu %llu %llu %llu %llu "
  91                 "%llu\n",
  92                 (unsigned long long)cputime64_to_clock_t(user),
  93                 (unsigned long long)cputime64_to_clock_t(nice),
  94                 (unsigned long long)cputime64_to_clock_t(system),
  95                 (unsigned long long)cputime64_to_clock_t(idle),
  96                 (unsigned long long)cputime64_to_clock_t(iowait),
  97                 (unsigned long long)cputime64_to_clock_t(irq),
  98                 (unsigned long long)cputime64_to_clock_t(softirq),
  99                 (unsigned long long)cputime64_to_clock_t(steal),
 100                 (unsigned long long)cputime64_to_clock_t(guest),
 101                 (unsigned long long)cputime64_to_clock_t(guest_nice));
 102         for_each_online_cpu(i) {
 103                 /* Copy values here to work around gcc-2.95.3, gcc-2.96 */
 104                 user = kcpustat_cpu(i).cpustat[CPUTIME_USER];
 105                 nice = kcpustat_cpu(i).cpustat[CPUTIME_NICE];
 106                 system = kcpustat_cpu(i).cpustat[CPUTIME_SYSTEM];
 107                 idle = get_idle_time(i);
 108                 iowait = get_iowait_time(i);
 109                 irq = kcpustat_cpu(i).cpustat[CPUTIME_IRQ];
 110                 softirq = kcpustat_cpu(i).cpustat[CPUTIME_SOFTIRQ];
 111                 steal = kcpustat_cpu(i).cpustat[CPUTIME_STEAL];
 112                 guest = kcpustat_cpu(i).cpustat[CPUTIME_GUEST];
 113                 guest_nice = kcpustat_cpu(i).cpustat[CPUTIME_GUEST_NICE];
 114                 seq_printf(p,
 115                         "cpu%d %llu %llu %llu %llu %llu %llu %llu %llu %llu "
 116                         "%llu\n",
 117                         i,
 118                         (unsigned long long)cputime64_to_clock_t(user),
 119                         (unsigned long long)cputime64_to_clock_t(nice),
 120                         (unsigned long long)cputime64_to_clock_t(system),
 121                         (unsigned long long)cputime64_to_clock_t(idle),
 122                         (unsigned long long)cputime64_to_clock_t(iowait),
 123                         (unsigned long long)cputime64_to_clock_t(irq),
 124                         (unsigned long long)cputime64_to_clock_t(softirq),
 125                         (unsigned long long)cputime64_to_clock_t(steal),
 126                         (unsigned long long)cputime64_to_clock_t(guest),
 127                         (unsigned long long)cputime64_to_clock_t(guest_nice));
 128         }
 129         seq_printf(p, "intr %llu", (unsigned long long)sum);
 130
 131         /* sum again ? it could be updated? */
 132         for_each_irq_nr(j)
 133                 seq_printf(p, " %u", kstat_irqs(j));
 134
 135         seq_printf(p,
 136                 "\nctxt %llu\n"
 137                 "btime %lu\n"
 138                 "processes %lu\n"
 139                 "procs_running %lu\n"
 140                 "procs_blocked %lu\n",
 141                 nr_context_switches(),
 142                 (unsigned long)jif,
 143                 total_forks,
 144                 nr_running(),
 145                 nr_iowait());
 146
 147         seq_printf(p, "softirq %llu", (unsigned long long)sum_softirq);
 148
 149         for (i = 0; i < NR_SOFTIRQS; i++)
 150                 seq_printf(p, " %u", per_softirq_sums[i]);
 151         seq_putc(p, '\n');
 152
 153         return 0;
 154 }
 155
 156 static int stat_open(struct inode *inode, struct file *file)
 157 {
 158         unsigned size = 4096 * (1 + num_possible_cpus() / 32);
 159         char *buf;
 160         struct seq_file *m;
 161         int res;
 162
 163         /* don't ask for more than the kmalloc() max size */
 164         if (size > KMALLOC_MAX_SIZE)
 165                 size = KMALLOC_MAX_SIZE;
 166         buf = kmalloc(size, GFP_KERNEL);
 167         if (!buf)
 168                 return -ENOMEM;
 169
 170         res = single_open(file, show_stat, NULL);
 171         if (!res) {
 172                 m = file->private_data;
 173                 m->buf = buf;
 174                 m->size = size;
 175         } else
 176                 kfree(buf);
 177         return res;
 178 }
 179
 180 static const struct file_operations proc_stat_operations = {
 181         .open           = stat_open,
 182         .read           = seq_read,
 183         .llseek         = seq_lseek,
 184         .release        = single_release,
 185 };
 186
 187 static int __init proc_stat_init(void)
 188 {
 189         proc_create("stat", 0, NULL, &proc_stat_operations);
 190         return 0;
 191 }
 192 module_init(proc_stat_init);