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
  22 #ifdef arch_idle_time
  23
  24 static cputime64_t get_idle_time(int cpu)
  25 {
  26         cputime64_t idle;
  27
  28         idle = kcpustat_cpu(cpu).cpustat[CPUTIME_IDLE];
  29         if (cpu_online(cpu) && !nr_iowait_cpu(cpu))
  30                 idle += arch_idle_time(cpu);
  31         return idle;
  32 }
  33
  34 static cputime64_t get_iowait_time(int cpu)
  35 {
  36         cputime64_t iowait;
  37
  38         iowait = kcpustat_cpu(cpu).cpustat[CPUTIME_IOWAIT];
  39         if (cpu_online(cpu) && nr_iowait_cpu(cpu))
  40                 iowait += arch_idle_time(cpu);
  41         return iowait;
  42 }
  43
  44 #else
  45
  46 static u64 get_idle_time(int cpu)
  47 {
  48         u64 idle, idle_time = -1ULL;
  49
  50         if (cpu_online(cpu))
  51                 idle_time = get_cpu_idle_time_us(cpu, NULL);
  52
  53         if (idle_time == -1ULL)
  54                 /* !NO_HZ or cpu offline so we can rely on cpustat.idle */
  55                 idle = kcpustat_cpu(cpu).cpustat[CPUTIME_IDLE];
  56         else
  57                 idle = usecs_to_cputime64(idle_time);
  58
  59         return idle;
  60 }
  61
  62 static u64 get_iowait_time(int cpu)
  63 {
  64         u64 iowait, iowait_time = -1ULL;
  65
  66         if (cpu_online(cpu))
  67                 iowait_time = get_cpu_iowait_time_us(cpu, NULL);
  68
  69         if (iowait_time == -1ULL)
  70                 /* !NO_HZ or cpu offline so we can rely on cpustat.iowait */
  71                 iowait = kcpustat_cpu(cpu).cpustat[CPUTIME_IOWAIT];
  72         else
  73                 iowait = usecs_to_cputime64(iowait_time);
  74
  75         return iowait;
  76 }
  77
  78 #endif
  79
  80 static int show_stat(struct seq_file *p, void *v)
  81 {
  82         int i, j;
  83         unsigned long jif;
  84         u64 user, nice, system, idle, iowait, irq, softirq, steal;
  85         u64 guest, guest_nice;
  86         u64 sum = 0;
  87         u64 sum_softirq = 0;
  88         unsigned int per_softirq_sums[NR_SOFTIRQS] = {0};
  89         struct timespec boottime;
  90
  91         user = nice = system = idle = iowait =
  92                 irq = softirq = steal = 0;
  93         guest = guest_nice = 0;
  94         getboottime(&boottime);
  95         jif = boottime.tv_sec;
  96
  97         for_each_possible_cpu(i) {
  98                 user += kcpustat_cpu(i).cpustat[CPUTIME_USER];
  99                 nice += kcpustat_cpu(i).cpustat[CPUTIME_NICE];
 100                 system += kcpustat_cpu(i).cpustat[CPUTIME_SYSTEM];
 101                 idle += get_idle_time(i);
 102                 iowait += get_iowait_time(i);
 103                 irq += kcpustat_cpu(i).cpustat[CPUTIME_IRQ];
 104                 softirq += kcpustat_cpu(i).cpustat[CPUTIME_SOFTIRQ];
 105                 steal += kcpustat_cpu(i).cpustat[CPUTIME_STEAL];
 106                 guest += kcpustat_cpu(i).cpustat[CPUTIME_GUEST];
 107                 guest_nice += kcpustat_cpu(i).cpustat[CPUTIME_GUEST_NICE];
 108                 sum += kstat_cpu_irqs_sum(i);
 109                 sum += arch_irq_stat_cpu(i);
 110
 111                 for (j = 0; j < NR_SOFTIRQS; j++) {
 112                         unsigned int softirq_stat = kstat_softirqs_cpu(j, i);
 113
 114                         per_softirq_sums[j] += softirq_stat;
 115                         sum_softirq += softirq_stat;
 116                 }
 117         }
 118         sum += arch_irq_stat();
 119
 120         seq_puts(p, "cpu ");
 121         seq_put_decimal_ull(p, ' ', cputime64_to_clock_t(user));
 122         seq_put_decimal_ull(p, ' ', cputime64_to_clock_t(nice));
 123         seq_put_decimal_ull(p, ' ', cputime64_to_clock_t(system));
 124         seq_put_decimal_ull(p, ' ', cputime64_to_clock_t(idle));
 125         seq_put_decimal_ull(p, ' ', cputime64_to_clock_t(iowait));
 126         seq_put_decimal_ull(p, ' ', cputime64_to_clock_t(irq));
 127         seq_put_decimal_ull(p, ' ', cputime64_to_clock_t(softirq));
 128         seq_put_decimal_ull(p, ' ', cputime64_to_clock_t(steal));
 129         seq_put_decimal_ull(p, ' ', cputime64_to_clock_t(guest));
 130         seq_put_decimal_ull(p, ' ', cputime64_to_clock_t(guest_nice));
 131         seq_putc(p, '\n');
 132
 133         for_each_online_cpu(i) {
 134                 /* Copy values here to work around gcc-2.95.3, gcc-2.96 */
 135                 user = kcpustat_cpu(i).cpustat[CPUTIME_USER];
 136                 nice = kcpustat_cpu(i).cpustat[CPUTIME_NICE];
 137                 system = kcpustat_cpu(i).cpustat[CPUTIME_SYSTEM];
 138                 idle = get_idle_time(i);
 139                 iowait = get_iowait_time(i);
 140                 irq = kcpustat_cpu(i).cpustat[CPUTIME_IRQ];
 141                 softirq = kcpustat_cpu(i).cpustat[CPUTIME_SOFTIRQ];
 142                 steal = kcpustat_cpu(i).cpustat[CPUTIME_STEAL];
 143                 guest = kcpustat_cpu(i).cpustat[CPUTIME_GUEST];
 144                 guest_nice = kcpustat_cpu(i).cpustat[CPUTIME_GUEST_NICE];
 145                 seq_printf(p, "cpu%d", i);
 146                 seq_put_decimal_ull(p, ' ', cputime64_to_clock_t(user));
 147                 seq_put_decimal_ull(p, ' ', cputime64_to_clock_t(nice));
 148                 seq_put_decimal_ull(p, ' ', cputime64_to_clock_t(system));
 149                 seq_put_decimal_ull(p, ' ', cputime64_to_clock_t(idle));
 150                 seq_put_decimal_ull(p, ' ', cputime64_to_clock_t(iowait));
 151                 seq_put_decimal_ull(p, ' ', cputime64_to_clock_t(irq));
 152                 seq_put_decimal_ull(p, ' ', cputime64_to_clock_t(softirq));
 153                 seq_put_decimal_ull(p, ' ', cputime64_to_clock_t(steal));
 154                 seq_put_decimal_ull(p, ' ', cputime64_to_clock_t(guest));
 155                 seq_put_decimal_ull(p, ' ', cputime64_to_clock_t(guest_nice));
 156                 seq_putc(p, '\n');
 157         }
 158         seq_printf(p, "intr %llu", (unsigned long long)sum);
 159
 160         /* sum again ? it could be updated? */
 161         for_each_irq_nr(j)
 162                 seq_put_decimal_ull(p, ' ', kstat_irqs(j));
 163
 164         seq_printf(p,
 165                 "\nctxt %llu\n"
 166                 "btime %lu\n"
 167                 "processes %lu\n"
 168                 "procs_running %lu\n"
 169                 "procs_blocked %lu\n",
 170                 nr_context_switches(),
 171                 (unsigned long)jif,
 172                 total_forks,
 173                 nr_running(),
 174                 nr_iowait());
 175
 176         seq_printf(p, "softirq %llu", (unsigned long long)sum_softirq);
 177
 178         for (i = 0; i < NR_SOFTIRQS; i++)
 179                 seq_put_decimal_ull(p, ' ', per_softirq_sums[i]);
 180         seq_putc(p, '\n');
 181
 182         return 0;
 183 }
 184
 185 static int stat_open(struct inode *inode, struct file *file)
 186 {
 187         size_t size = 1024 + 128 * num_possible_cpus();
 188         char *buf;
 189         struct seq_file *m;
 190         int res;
 191
 192         /* minimum size to display an interrupt count : 2 bytes */
 193         size += 2 * nr_irqs;
 194
 195         /* don't ask for more than the kmalloc() max size */
 196         if (size > KMALLOC_MAX_SIZE)
 197                 size = KMALLOC_MAX_SIZE;
 198         buf = kmalloc(size, GFP_KERNEL);
 199         if (!buf)
 200                 return -ENOMEM;
 201
 202         res = single_open(file, show_stat, NULL);
 203         if (!res) {
 204                 m = file->private_data;
 205                 m->buf = buf;
 206                 m->size = ksize(buf);
 207         } else
 208                 kfree(buf);
 209         return res;
 210 }
 211
 212 static const struct file_operations proc_stat_operations = {
 213         .open           = stat_open,
 214         .read           = seq_read,
 215         .llseek         = seq_lseek,
 216         .release        = single_release,
 217 };
 218
 219 static int __init proc_stat_init(void)
 220 {
 221         proc_create("stat", 0, NULL, &proc_stat_operations);
 222         return 0;
 223 }
 224 module_init(proc_stat_init);