Re: [PATCH 2/2] thermal: Move therm_throt there from x86/mce

[Peter Zijlstra]

On Fri, Jan 08, 2021 at 09:54:30AM +0100, Borislav Petkov wrote:
> +#ifdef CONFIG_X86_THERMAL_VECTOR
> +static void unexpected_thermal_interrupt(void)
> +{
> +	pr_err("CPU%d: Unexpected LVT thermal interrupt!\n",
> +		smp_processor_id());
> +}
> +
> +static void (*smp_thermal_vector)(void) = unexpected_thermal_interrupt;
> +
> +void thermal_set_handler(void (*handler)(void))
> +{
> +	if (handler) {
		WARN_ON(smp_thermal_vector != unexpected_thermal_interrupt);
> +		smp_thermal_vector = handler;
> +	} else
> +		smp_thermal_vector = unexpected_thermal_interrupt;
> +}
> +EXPORT_SYMBOL_GPL(thermal_set_handler);

You really don't want multiple modules to touch that at the same time.

> +DEFINE_IDTENTRY_SYSVEC(sysvec_thermal)
> +{
> +	trace_thermal_apic_entry(THERMAL_APIC_VECTOR);
> +	inc_irq_stat(irq_thermal_count);
> +	smp_thermal_vector();
> +	trace_thermal_apic_exit(THERMAL_APIC_VECTOR);
> +	ack_APIC_irq();
> +}
> +#endif