1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3  * debugfs file to track time spent in suspend
4  *
5  * Copyright (c) 2011, Google, Inc.
6  */
7 
8 #include <linux/debugfs.h>
9 #include <linux/err.h>
10 #include <linux/init.h>
11 #include <linux/kernel.h>
12 #include <linux/seq_file.h>
13 #include <linux/suspend.h>
14 #include <linux/time.h>
15 
16 #include "timekeeping_internal.h"
17 
18 #define NUM_BINS 32
19 
20 static unsigned int sleep_time_bin[NUM_BINS] = {0};
21 
22 static int tk_debug_sleep_time_show(struct seq_file *s, void *data)
23 {
24 	unsigned int bin;
25 	seq_puts(s, "      time (secs)        count\n");
26 	seq_puts(s, "------------------------------\n");
27 	for (bin = 0; bin < 32; bin++) {
28 		if (sleep_time_bin[bin] == 0)
29 			continue;
30 		seq_printf(s, "%10u - %-10u %4u\n",
31 			bin ? 1 << (bin - 1) : 0, 1 << bin,
32 				sleep_time_bin[bin]);
33 	}
34 	return 0;
35 }
36 DEFINE_SHOW_ATTRIBUTE(tk_debug_sleep_time);
37 
38 static int __init tk_debug_sleep_time_init(void)
39 {
40 	struct dentry *d;
41 
42 	d = debugfs_create_file("sleep_time", 0444, NULL, NULL,
43 		&tk_debug_sleep_time_fops);
44 	if (!d) {
45 		pr_err("Failed to create sleep_time debug file\n");
46 		return -ENOMEM;
47 	}
48 
49 	return 0;
50 }
51 late_initcall(tk_debug_sleep_time_init);
52 
53 void tk_debug_account_sleep_time(const struct timespec64 *t)
54 {
55 	/* Cap bin index so we don't overflow the array */
56 	int bin = min(fls(t->tv_sec), NUM_BINS-1);
57 
58 	sleep_time_bin[bin]++;
59 	pm_deferred_pr_dbg("Timekeeping suspended for %lld.%03lu seconds\n",
60 			   (s64)t->tv_sec, t->tv_nsec / NSEC_PER_MSEC);
61 }
62 
63