static int nmi_timer_setup(void)
{
int cpu, err;
u64 period;
/* clock cycles per tick: */
period = (u64)cpu_khz * 1000;
do_div(period, HZ);
nmi_timer_attr.sample_period = period;
cpu_notifier_register_begin();
err = __register_cpu_notifier(&nmi_timer_cpu_nb);
if (err)
goto out;
/* can't attach events to offline cpus: */
for_each_online_cpu(cpu) {
err = nmi_timer_start_cpu(cpu);
if (err) {
cpu_notifier_register_done();
nmi_timer_shutdown();
return err;
}
}
out:
cpu_notifier_register_done();
return err;
}
static int nmi_timer_setup(void)
{
int err;
u64 period;
/* clock cycles per tick: */
period = (u64)cpu_khz * 1000;
do_div(period, HZ);
nmi_timer_attr.sample_period = period;
err = cpuhp_setup_state(CPUHP_AP_ONLINE_DYN, "oprofile/nmi:online",
nmi_timer_cpu_online, nmi_timer_cpu_predown);
if (err < 0) {
nmi_timer_shutdown();
return err;
}
hp_online = err;
return 0;
}
int __init op_nmi_timer_init(struct oprofile_operations *ops)
{
int err = 0;
err = nmi_timer_setup();
if (err)
return err;
nmi_timer_shutdown(); /* only check, don't alloc */
ops->create_files = NULL;
ops->setup = nmi_timer_setup;
ops->shutdown = nmi_timer_shutdown;
ops->start = nmi_timer_start;
ops->stop = nmi_timer_stop;
ops->cpu_type = "timer";
printk(KERN_INFO "oprofile: using NMI timer interrupt.\n");
return 0;
}
