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_show_sleep_time(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 37 static int tk_debug_sleep_time_open(struct inode *inode, struct file *file) 38 { 39 return single_open(file, tk_debug_show_sleep_time, NULL); 40 } 41 42 static const struct file_operations tk_debug_sleep_time_fops = { 43 .open = tk_debug_sleep_time_open, 44 .read = seq_read, 45 .llseek = seq_lseek, 46 .release = single_release, 47 }; 48 49 static int __init tk_debug_sleep_time_init(void) 50 { 51 struct dentry *d; 52 53 d = debugfs_create_file("sleep_time", 0444, NULL, NULL, 54 &tk_debug_sleep_time_fops); 55 if (!d) { 56 pr_err("Failed to create sleep_time debug file\n"); 57 return -ENOMEM; 58 } 59 60 return 0; 61 } 62 late_initcall(tk_debug_sleep_time_init); 63 64 void tk_debug_account_sleep_time(const struct timespec64 *t) 65 { 66 /* Cap bin index so we don't overflow the array */ 67 int bin = min(fls(t->tv_sec), NUM_BINS-1); 68 69 sleep_time_bin[bin]++; 70 pm_deferred_pr_dbg("Timekeeping suspended for %lld.%03lu seconds\n", 71 (s64)t->tv_sec, t->tv_nsec / NSEC_PER_MSEC); 72 } 73 74