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		2a15385742
		
			
		
	
	
	
	
		
			
			The mgtime_floor value is a global variable for tracking the latest fine-grained timestamp handed out. Because it's a global, track the number of times that a new floor value is assigned. Add a new percpu counter to the timekeeping code to track the number of floor swap events that have occurred. A later patch will add a debugfs file to display this counter alongside other stats involving multigrain timestamps. Signed-off-by: Jeff Layton <jlayton@kernel.org> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Tested-by: Randy Dunlap <rdunlap@infradead.org> # documentation bits Link: https://lore.kernel.org/all/20241002-mgtime-v10-2-d1c4717f5284@kernel.org Signed-off-by: Christian Brauner <brauner@kernel.org>
		
			
				
	
	
		
			68 lines
		
	
	
	
		
			1.6 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			68 lines
		
	
	
	
		
			1.6 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
| // SPDX-License-Identifier: GPL-2.0+
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| /*
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|  * debugfs file to track time spent in suspend
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|  *
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|  * Copyright (c) 2011, Google, Inc.
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|  */
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| 
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| #include <linux/debugfs.h>
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| #include <linux/err.h>
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| #include <linux/init.h>
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| #include <linux/kernel.h>
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| #include <linux/seq_file.h>
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| #include <linux/suspend.h>
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| #include <linux/time.h>
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| 
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| #include "timekeeping_internal.h"
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| 
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| #define NUM_BINS 32
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| 
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| /* Incremented every time mg_floor is updated */
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| DEFINE_PER_CPU(unsigned long, timekeeping_mg_floor_swaps);
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| 
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| static unsigned int sleep_time_bin[NUM_BINS] = {0};
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| 
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| static int tk_debug_sleep_time_show(struct seq_file *s, void *data)
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| {
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| 	unsigned int bin;
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| 	seq_puts(s, "      time (secs)        count\n");
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| 	seq_puts(s, "------------------------------\n");
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| 	for (bin = 0; bin < 32; bin++) {
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| 		if (sleep_time_bin[bin] == 0)
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| 			continue;
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| 		seq_printf(s, "%10u - %-10u %4u\n",
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| 			bin ? 1 << (bin - 1) : 0, 1 << bin,
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| 				sleep_time_bin[bin]);
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| 	}
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| 	return 0;
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| }
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| DEFINE_SHOW_ATTRIBUTE(tk_debug_sleep_time);
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| 
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| static int __init tk_debug_sleep_time_init(void)
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| {
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| 	debugfs_create_file("sleep_time", 0444, NULL, NULL,
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| 			    &tk_debug_sleep_time_fops);
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| 	return 0;
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| }
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| late_initcall(tk_debug_sleep_time_init);
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| 
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| void tk_debug_account_sleep_time(const struct timespec64 *t)
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| {
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| 	/* Cap bin index so we don't overflow the array */
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| 	int bin = min(fls(t->tv_sec), NUM_BINS-1);
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| 
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| 	sleep_time_bin[bin]++;
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| 	pm_deferred_pr_dbg("Timekeeping suspended for %lld.%03lu seconds\n",
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| 			   (s64)t->tv_sec, t->tv_nsec / NSEC_PER_MSEC);
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| }
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| 
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| unsigned long timekeeping_get_mg_floor_swaps(void)
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| {
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| 	unsigned long sum = 0;
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| 	int cpu;
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| 
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| 	for_each_possible_cpu(cpu)
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| 		sum += data_race(per_cpu(timekeeping_mg_floor_swaps, cpu));
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| 
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| 	return sum;
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| }
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