tjh.dev
Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel
os
linux
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/kernel_stat.h>
9
10static int uptime_proc_show(struct seq_file *m, void *v)
11{
12 struct timespec uptime;
13 struct timespec idle;
14 u64 nsec;
15 u32 rem;
16 int i;
17
18 nsec = 0;
19 for_each_possible_cpu(i)
20 nsec += (__force u64) kcpustat_cpu(i).cpustat[CPUTIME_IDLE];
21
22 get_monotonic_boottime(&uptime);
23 idle.tv_sec = div_u64_rem(nsec, NSEC_PER_SEC, &rem);
24 idle.tv_nsec = rem;
25 seq_printf(m, "%lu.%02lu %lu.%02lu\n",
26 (unsigned long) uptime.tv_sec,
27 (uptime.tv_nsec / (NSEC_PER_SEC / 100)),
28 (unsigned long) idle.tv_sec,
29 (idle.tv_nsec / (NSEC_PER_SEC / 100)));
30 return 0;
31}
32
33static int uptime_proc_open(struct inode *inode, struct file *file)
34{
35 return single_open(file, uptime_proc_show, NULL);
36}
37
38static const struct file_operations uptime_proc_fops = {
39 .open = uptime_proc_open,
40 .read = seq_read,
41 .llseek = seq_lseek,
42 .release = single_release,
43};
44
45static int __init proc_uptime_init(void)
46{
47 proc_create("uptime", 0, NULL, &uptime_proc_fops);
48 return 0;
49}
50fs_initcall(proc_uptime_init);