1 /* 2 * debugfs file to track time spent in suspend 3 * 4 * Copyright (c) 2011, Google, Inc. 5 * 6 * This program is free software; you can redistribute it and/or modify 7 * it under the terms of the GNU General Public License as published by 8 * the Free Software Foundation; either version 2 of the License, or 9 * (at your option) any later version. 10 * 11 * This program is distributed in the hope that it will be useful, but WITHOUT 12 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or 13 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for 14 * more details. 15 */ 16 17 #include <linux/debugfs.h> 18 #include <linux/err.h> 19 #include <linux/init.h> 20 #include <linux/kernel.h> 21 #include <linux/seq_file.h> 22 #include <linux/time.h> 23 24 static unsigned int sleep_time_bin[32] = {0}; 25 26 static int tk_debug_show_sleep_time(struct seq_file *s, void *data) 27 { 28 unsigned int bin; 29 seq_puts(s, " time (secs) count\n"); 30 seq_puts(s, "------------------------------\n"); 31 for (bin = 0; bin < 32; bin++) { 32 if (sleep_time_bin[bin] == 0) 33 continue; 34 seq_printf(s, "%10u - %-10u %4u\n", 35 bin ? 1 << (bin - 1) : 0, 1 << bin, 36 sleep_time_bin[bin]); 37 } 38 return 0; 39 } 40 41 static int tk_debug_sleep_time_open(struct inode *inode, struct file *file) 42 { 43 return single_open(file, tk_debug_show_sleep_time, NULL); 44 } 45 46 static const struct file_operations tk_debug_sleep_time_fops = { 47 .open = tk_debug_sleep_time_open, 48 .read = seq_read, 49 .llseek = seq_lseek, 50 .release = single_release, 51 }; 52 53 static int __init tk_debug_sleep_time_init(void) 54 { 55 struct dentry *d; 56 57 d = debugfs_create_file("sleep_time", 0444, NULL, NULL, 58 &tk_debug_sleep_time_fops); 59 if (!d) { 60 pr_err("Failed to create sleep_time debug file\n"); 61 return -ENOMEM; 62 } 63 64 return 0; 65 } 66 late_initcall(tk_debug_sleep_time_init); 67 68 void tk_debug_account_sleep_time(struct timespec *t) 69 { 70 sleep_time_bin[fls(t->tv_sec)]++; 71 } 72 73