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 /* Incremented every time mg_floor is updated */ 21 DEFINE_PER_CPU(unsigned long, timekeeping_mg_floor_swaps); 22 23 static unsigned int sleep_time_bin[NUM_BINS] = {0}; 24 25 static int tk_debug_sleep_time_show(struct seq_file *s, void *data) 26 { 27 unsigned int bin; 28 seq_puts(s, " time (secs) count\n"); 29 seq_puts(s, "------------------------------\n"); 30 for (bin = 0; bin < 32; bin++) { 31 if (sleep_time_bin[bin] == 0) 32 continue; 33 seq_printf(s, "%10u - %-10u %4u\n", 34 bin ? 1 << (bin - 1) : 0, 1 << bin, 35 sleep_time_bin[bin]); 36 } 37 return 0; 38 } 39 DEFINE_SHOW_ATTRIBUTE(tk_debug_sleep_time); 40 41 static int __init tk_debug_sleep_time_init(void) 42 { 43 debugfs_create_file("sleep_time", 0444, NULL, NULL, 44 &tk_debug_sleep_time_fops); 45 return 0; 46 } 47 late_initcall(tk_debug_sleep_time_init); 48 49 void tk_debug_account_sleep_time(const struct timespec64 *t) 50 { 51 /* Cap bin index so we don't overflow the array */ 52 int bin = min(fls(t->tv_sec), NUM_BINS-1); 53 54 sleep_time_bin[bin]++; 55 pm_deferred_pr_dbg("Timekeeping suspended for %lld.%03lu seconds\n", 56 (s64)t->tv_sec, t->tv_nsec / NSEC_PER_MSEC); 57 } 58 59 unsigned long timekeeping_get_mg_floor_swaps(void) 60 { 61 unsigned long sum = 0; 62 int cpu; 63 64 for_each_possible_cpu(cpu) 65 sum += data_race(per_cpu(timekeeping_mg_floor_swaps, cpu)); 66 67 return sum; 68 } 69