/**
|
* @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 = this_cpu_ptr(&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_timer_online(unsigned int cpu)
|
{
|
local_irq_disable();
|
__oprofile_hrtimer_start(NULL);
|
local_irq_enable();
|
return 0;
|
}
|
|
static int oprofile_timer_prep_down(unsigned int cpu)
|
{
|
__oprofile_hrtimer_stop(cpu);
|
return 0;
|
}
|
|
static enum cpuhp_state hp_online;
|
|
static int oprofile_hrtimer_setup(void)
|
{
|
int ret;
|
|
ret = cpuhp_setup_state_nocalls(CPUHP_AP_ONLINE_DYN,
|
"oprofile/timer:online",
|
oprofile_timer_online,
|
oprofile_timer_prep_down);
|
if (ret < 0)
|
return ret;
|
hp_online = ret;
|
return 0;
|
}
|
|
static void oprofile_hrtimer_shutdown(void)
|
{
|
cpuhp_remove_state_nocalls(hp_online);
|
}
|
|
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;
|
}
|
