xref: /OK3568_Linux_fs/kernel/fs/proc/uptime.c (revision 4882a59341e53eb6f0b4789bf948001014eff981)
1*4882a593Smuzhiyun // SPDX-License-Identifier: GPL-2.0
2*4882a593Smuzhiyun #include <linux/fs.h>
3*4882a593Smuzhiyun #include <linux/init.h>
4*4882a593Smuzhiyun #include <linux/proc_fs.h>
5*4882a593Smuzhiyun #include <linux/sched.h>
6*4882a593Smuzhiyun #include <linux/seq_file.h>
7*4882a593Smuzhiyun #include <linux/time.h>
8*4882a593Smuzhiyun #include <linux/time_namespace.h>
9*4882a593Smuzhiyun #include <linux/kernel_stat.h>
10*4882a593Smuzhiyun 
uptime_proc_show(struct seq_file * m,void * v)11*4882a593Smuzhiyun static int uptime_proc_show(struct seq_file *m, void *v)
12*4882a593Smuzhiyun {
13*4882a593Smuzhiyun 	struct timespec64 uptime;
14*4882a593Smuzhiyun 	struct timespec64 idle;
15*4882a593Smuzhiyun 	u64 idle_nsec;
16*4882a593Smuzhiyun 	u32 rem;
17*4882a593Smuzhiyun 	int i;
18*4882a593Smuzhiyun 
19*4882a593Smuzhiyun 	idle_nsec = 0;
20*4882a593Smuzhiyun 	for_each_possible_cpu(i) {
21*4882a593Smuzhiyun 		struct kernel_cpustat kcs;
22*4882a593Smuzhiyun 
23*4882a593Smuzhiyun 		kcpustat_cpu_fetch(&kcs, i);
24*4882a593Smuzhiyun 		idle_nsec += get_idle_time(&kcs, i);
25*4882a593Smuzhiyun 	}
26*4882a593Smuzhiyun 
27*4882a593Smuzhiyun 	ktime_get_boottime_ts64(&uptime);
28*4882a593Smuzhiyun 	timens_add_boottime(&uptime);
29*4882a593Smuzhiyun 
30*4882a593Smuzhiyun 	idle.tv_sec = div_u64_rem(idle_nsec, NSEC_PER_SEC, &rem);
31*4882a593Smuzhiyun 	idle.tv_nsec = rem;
32*4882a593Smuzhiyun 	seq_printf(m, "%lu.%02lu %lu.%02lu\n",
33*4882a593Smuzhiyun 			(unsigned long) uptime.tv_sec,
34*4882a593Smuzhiyun 			(uptime.tv_nsec / (NSEC_PER_SEC / 100)),
35*4882a593Smuzhiyun 			(unsigned long) idle.tv_sec,
36*4882a593Smuzhiyun 			(idle.tv_nsec / (NSEC_PER_SEC / 100)));
37*4882a593Smuzhiyun 	return 0;
38*4882a593Smuzhiyun }
39*4882a593Smuzhiyun 
proc_uptime_init(void)40*4882a593Smuzhiyun static int __init proc_uptime_init(void)
41*4882a593Smuzhiyun {
42*4882a593Smuzhiyun 	proc_create_single("uptime", 0, NULL, uptime_proc_show);
43*4882a593Smuzhiyun 	return 0;
44*4882a593Smuzhiyun }
45*4882a593Smuzhiyun fs_initcall(proc_uptime_init);
46