Line data    Source code

       1             : // SPDX-License-Identifier: GPL-2.0
       2             : #include <linux/fs.h>
       3             : #include <linux/init.h>
       4             : #include <linux/proc_fs.h>
       5             : #include <linux/sched.h>
       6             : #include <linux/seq_file.h>
       7             : #include <linux/time.h>
       8             : #include <linux/time_namespace.h>
       9             : #include <linux/kernel_stat.h>
      10             : 
      11           0 : static int uptime_proc_show(struct seq_file *m, void *v)
      12             : {
      13             :         struct timespec64 uptime;
      14             :         struct timespec64 idle;
      15             :         u64 idle_nsec;
      16             :         u32 rem;
      17             :         int i;
      18             : 
      19           0 :         idle_nsec = 0;
      20           0 :         for_each_possible_cpu(i) {
      21             :                 struct kernel_cpustat kcs;
      22             : 
      23           0 :                 kcpustat_cpu_fetch(&kcs, i);
      24           0 :                 idle_nsec += get_idle_time(&kcs, i);
      25             :         }
      26             : 
      27           0 :         ktime_get_boottime_ts64(&uptime);
      28           0 :         timens_add_boottime(&uptime);
      29             : 
      30           0 :         idle.tv_sec = div_u64_rem(idle_nsec, NSEC_PER_SEC, &rem);
      31           0 :         idle.tv_nsec = rem;
      32           0 :         seq_printf(m, "%lu.%02lu %lu.%02lu\n",
      33           0 :                         (unsigned long) uptime.tv_sec,
      34           0 :                         (uptime.tv_nsec / (NSEC_PER_SEC / 100)),
      35             :                         (unsigned long) idle.tv_sec,
      36             :                         (idle.tv_nsec / (NSEC_PER_SEC / 100)));
      37           0 :         return 0;
      38             : }
      39             : 
      40           1 : static int __init proc_uptime_init(void)
      41             : {
      42           1 :         proc_create_single("uptime", 0, NULL, uptime_proc_show);
      43           1 :         return 0;
      44             : }
      45             : fs_initcall(proc_uptime_init);