/** * @file timer_int.c * * @remark Copyright 2002 OProfile authors * @remark Read the file COPYING * * @author John Levon <levon@movementarian.org> */ #include <linux/kernel.h>#include <linux/notifier.h>#include <linux/smp.h>#include <linux/oprofile.h>#include <linux/profile.h>#include <linux/init.h>#include <linux/cpu.h>#include <linux/hrtimer.h>#include <asm/irq_regs.h>#include <asm/ptrace.h> #include "oprof.h" static DEFINE_PER_CPU(struct hrtimer, oprofile_hrtimer);static int ctr_running; static enum hrtimer_restart oprofile_hrtimer_notify(struct hrtimer *hrtimer){	oprofile_add_sample(get_irq_regs(), 0);	hrtimer_forward_now(hrtimer, ns_to_ktime(TICK_NSEC));	return HRTIMER_RESTART;} static void __oprofile_hrtimer_start(void *unused){	struct hrtimer *hrtimer = &__get_cpu_var(oprofile_hrtimer); 	if (!ctr_running)		return; 	hrtimer_init(hrtimer, CLOCK_MONOTONIC, HRTIMER_MODE_REL);	hrtimer->function = oprofile_hrtimer_notify; 	hrtimer_start(hrtimer, ns_to_ktime(TICK_NSEC),		      HRTIMER_MODE_REL_PINNED);} static int oprofile_hrtimer_start(void){	get_online_cpus();	ctr_running = 1;	on_each_cpu(__oprofile_hrtimer_start, NULL, 1);	put_online_cpus();	return 0;} static void __oprofile_hrtimer_stop(int cpu){	struct hrtimer *hrtimer = &per_cpu(oprofile_hrtimer, cpu); 	if (!ctr_running)		return; 	hrtimer_cancel(hrtimer);} static void oprofile_hrtimer_stop(void){	int cpu; 	get_online_cpus();	for_each_online_cpu(cpu)		__oprofile_hrtimer_stop(cpu);	ctr_running = 0;	put_online_cpus();} static int oprofile_cpu_notify(struct notifier_block *self,			       unsigned long action, void *hcpu){	long cpu = (long) hcpu; 	switch (action) {	case CPU_ONLINE:	case CPU_ONLINE_FROZEN:		smp_call_function_single(cpu, __oprofile_hrtimer_start,					 NULL, 1);		break;	case CPU_DEAD:	case CPU_DEAD_FROZEN:		__oprofile_hrtimer_stop(cpu);		break;	}	return NOTIFY_OK;} static struct notifier_block __refdata oprofile_cpu_notifier = {	.notifier_call = oprofile_cpu_notify,}; static int oprofile_hrtimer_setup(void){	return register_hotcpu_notifier(&oprofile_cpu_notifier);} static void oprofile_hrtimer_shutdown(void){	unregister_hotcpu_notifier(&oprofile_cpu_notifier);} int oprofile_timer_init(struct oprofile_operations *ops){	ops->create_files	= NULL;	ops->setup		= oprofile_hrtimer_setup;	ops->shutdown		= oprofile_hrtimer_shutdown;	ops->start		= oprofile_hrtimer_start;	ops->stop		= oprofile_hrtimer_stop;	ops->cpu_type		= "timer";	printk(KERN_INFO "oprofile: using timer interrupt.\n");	return 0;}