tjh.dev
Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel
os
linux
1#include <linux/fs.h>
2#include <linux/init.h>
3#include <linux/proc_fs.h>
4#include <linux/sched.h>
5#include <linux/seq_file.h>
6#include <linux/time.h>
7#include <linux/kernel_stat.h>
8
9static int uptime_proc_show(struct seq_file *m, void *v)
10{
11 struct timespec uptime;
12 struct timespec idle;
13 u64 nsec;
14 u32 rem;
15 int i;
16
17 nsec = 0;
18 for_each_possible_cpu(i)
19 nsec += (__force u64) kcpustat_cpu(i).cpustat[CPUTIME_IDLE];
20
21 get_monotonic_boottime(&uptime);
22 idle.tv_sec = div_u64_rem(nsec, NSEC_PER_SEC, &rem);
23 idle.tv_nsec = rem;
24 seq_printf(m, "%lu.%02lu %lu.%02lu\n",
25 (unsigned long) uptime.tv_sec,
26 (uptime.tv_nsec / (NSEC_PER_SEC / 100)),
27 (unsigned long) idle.tv_sec,
28 (idle.tv_nsec / (NSEC_PER_SEC / 100)));
29 return 0;
30}
31
32static int uptime_proc_open(struct inode *inode, struct file *file)
33{
34 return single_open(file, uptime_proc_show, NULL);
35}
36
37static const struct file_operations uptime_proc_fops = {
38 .open = uptime_proc_open,
39 .read = seq_read,
40 .llseek = seq_lseek,
41 .release = single_release,
42};
43
44static int __init proc_uptime_init(void)
45{
46 proc_create("uptime", 0, NULL, &uptime_proc_fops);
47 return 0;
48}
49fs_initcall(proc_uptime_init);