init.c
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/**
* @file init.c
*
* @remark Copyright 2002 OProfile authors
* @remark Read the file COPYING
*
* @author John Levon <levon@movementarian.org>
*/
#include <linux/kernel.h>
#include <linux/oprofile.h>
#include <linux/errno.h>
#include <linux/init.h>
#include <linux/param.h> /* for HZ */
#ifdef CONFIG_SPARC64
#include <linux/notifier.h>
#include <linux/rcupdate.h>
#include <linux/kdebug.h>
#include <asm/nmi.h>
static int profile_timer_exceptions_notify(struct notifier_block *self,
unsigned long val, void *data)
{
struct die_args *args = data;
int ret = NOTIFY_DONE;
switch (val) {
case DIE_NMI:
oprofile_add_sample(args->regs, 0);
ret = NOTIFY_STOP;
break;
default:
break;
}
return ret;
}
static struct notifier_block profile_timer_exceptions_nb = {
.notifier_call = profile_timer_exceptions_notify,
};
static int timer_start(void)
{
if (register_die_notifier(&profile_timer_exceptions_nb))
return 1;
nmi_adjust_hz(HZ);
return 0;
}
static void timer_stop(void)
{
nmi_adjust_hz(1);
unregister_die_notifier(&profile_timer_exceptions_nb);
synchronize_sched(); /* Allow already-started NMIs to complete. */
}
static int op_nmi_timer_init(struct oprofile_operations *ops)
{
if (atomic_read(&nmi_active) <= 0)
return -ENODEV;
ops->start = timer_start;
ops->stop = timer_stop;
ops->cpu_type = "timer";
printk(KERN_INFO "oprofile: Using perfctr NMI timer interrupt.\n");
return 0;
}
#endif
int __init oprofile_arch_init(struct oprofile_operations *ops)
{
int ret = -ENODEV;
#ifdef CONFIG_SPARC64
ret = op_nmi_timer_init(ops);
if (!ret)
return ret;
#endif
return ret;
}
void oprofile_arch_exit(void)
{
}