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