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 #include "internal.h"
11
uptime_proc_show(struct seq_file * m,void * v)12 static int uptime_proc_show(struct seq_file *m, void *v)
13 {
14 struct timespec64 uptime;
15 struct timespec64 idle;
16 u64 idle_nsec;
17 u32 rem;
18 int i;
19
20 idle_nsec = 0;
21 for_each_possible_cpu(i) {
22 struct kernel_cpustat kcs;
23
24 kcpustat_cpu_fetch(&kcs, i);
25 idle_nsec += get_idle_time(&kcs, i);
26 }
27
28 ktime_get_boottime_ts64(&uptime);
29 timens_add_boottime(&uptime);
30
31 idle.tv_sec = div_u64_rem(idle_nsec, NSEC_PER_SEC, &rem);
32 idle.tv_nsec = rem;
33 seq_printf(m, "%lu.%02lu %lu.%02lu\n",
34 (unsigned long) uptime.tv_sec,
35 (uptime.tv_nsec / (NSEC_PER_SEC / 100)),
36 (unsigned long) idle.tv_sec,
37 (idle.tv_nsec / (NSEC_PER_SEC / 100)));
38 return 0;
39 }
40
proc_uptime_init(void)41 static int __init proc_uptime_init(void)
42 {
43 struct proc_dir_entry *pde;
44
45 pde = proc_create_single("uptime", 0, NULL, uptime_proc_show);
46 pde_make_permanent(pde);
47 return 0;
48 }
49 fs_initcall(proc_uptime_init);
50