123 lines
		
	
	
		
			2.5 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			123 lines
		
	
	
		
			2.5 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
| /**
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|  * @file timer_int.c
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|  *
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|  * @remark Copyright 2002 OProfile authors
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|  * @remark Read the file COPYING
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|  *
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|  * @author John Levon <levon@movementarian.org>
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|  */
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| 
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| #include <linux/kernel.h>
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| #include <linux/notifier.h>
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| #include <linux/smp.h>
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| #include <linux/oprofile.h>
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| #include <linux/profile.h>
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| #include <linux/init.h>
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| #include <linux/cpu.h>
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| #include <linux/hrtimer.h>
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| #include <asm/irq_regs.h>
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| #include <asm/ptrace.h>
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| 
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| #include "oprof.h"
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| 
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| static DEFINE_PER_CPU(struct hrtimer, oprofile_hrtimer);
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| static int ctr_running;
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| 
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| static enum hrtimer_restart oprofile_hrtimer_notify(struct hrtimer *hrtimer)
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| {
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| 	oprofile_add_sample(get_irq_regs(), 0);
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| 	hrtimer_forward_now(hrtimer, ns_to_ktime(TICK_NSEC));
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| 	return HRTIMER_RESTART;
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| }
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| 
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| static void __oprofile_hrtimer_start(void *unused)
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| {
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| 	struct hrtimer *hrtimer = this_cpu_ptr(&oprofile_hrtimer);
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| 
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| 	if (!ctr_running)
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| 		return;
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| 
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| 	hrtimer_init(hrtimer, CLOCK_MONOTONIC, HRTIMER_MODE_REL);
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| 	hrtimer->function = oprofile_hrtimer_notify;
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| 
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| 	hrtimer_start(hrtimer, ns_to_ktime(TICK_NSEC),
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| 		      HRTIMER_MODE_REL_PINNED);
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| }
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| 
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| static int oprofile_hrtimer_start(void)
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| {
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| 	get_online_cpus();
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| 	ctr_running = 1;
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| 	on_each_cpu(__oprofile_hrtimer_start, NULL, 1);
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| 	put_online_cpus();
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| 	return 0;
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| }
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| 
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| static void __oprofile_hrtimer_stop(int cpu)
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| {
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| 	struct hrtimer *hrtimer = &per_cpu(oprofile_hrtimer, cpu);
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| 
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| 	if (!ctr_running)
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| 		return;
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| 
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| 	hrtimer_cancel(hrtimer);
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| }
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| 
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| static void oprofile_hrtimer_stop(void)
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| {
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| 	int cpu;
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| 
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| 	get_online_cpus();
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| 	for_each_online_cpu(cpu)
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| 		__oprofile_hrtimer_stop(cpu);
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| 	ctr_running = 0;
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| 	put_online_cpus();
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| }
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| 
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| static int oprofile_timer_online(unsigned int cpu)
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| {
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| 	local_irq_disable();
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| 	__oprofile_hrtimer_start(NULL);
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| 	local_irq_enable();
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| 	return 0;
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| }
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| 
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| static int oprofile_timer_prep_down(unsigned int cpu)
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| {
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| 	__oprofile_hrtimer_stop(cpu);
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| 	return 0;
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| }
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| 
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| static enum cpuhp_state hp_online;
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| 
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| static int oprofile_hrtimer_setup(void)
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| {
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| 	int ret;
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| 
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| 	ret = cpuhp_setup_state_nocalls(CPUHP_AP_ONLINE_DYN,
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| 					"oprofile/timer:online",
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| 					oprofile_timer_online,
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| 					oprofile_timer_prep_down);
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| 	if (ret < 0)
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| 		return ret;
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| 	hp_online = ret;
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| 	return 0;
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| }
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| 
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| static void oprofile_hrtimer_shutdown(void)
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| {
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| 	cpuhp_remove_state_nocalls(hp_online);
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| }
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| 
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| int oprofile_timer_init(struct oprofile_operations *ops)
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| {
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| 	ops->create_files	= NULL;
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| 	ops->setup		= oprofile_hrtimer_setup;
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| 	ops->shutdown		= oprofile_hrtimer_shutdown;
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| 	ops->start		= oprofile_hrtimer_start;
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| 	ops->stop		= oprofile_hrtimer_stop;
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| 	ops->cpu_type		= "timer";
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| 	printk(KERN_INFO "oprofile: using timer interrupt.\n");
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| 	return 0;
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| }
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