Re: [RFC 8/8] x86_64: Support for new UV apic

[Jack Steiner <steiner@sgi.com>]

On Tue, Mar 25, 2008 at 03:30:59PM +0100, Ingo Molnar wrote:
> 
> * Jack Steiner <steiner@sgi.com> wrote:
> 
> > Index: linux/arch/x86/kernel/genapic_64.c
> 
> > @@ -69,7 +73,16 @@ void send_IPI_self(int vector)
> >  
> >  unsigned int get_apic_id(void)
> >  {
> > -	return (apic_read(APIC_ID) >> 24) & 0xFFu;
> > +	unsigned int id;
> > +
> > +	preempt_disable();
> > +	id = apic_read(APIC_ID);
> > +	if (uv_system_type >= UV_X2APIC)
> > +		id  |= __get_cpu_var(x2apic_extra_bits);
> > +	else
> > +		id = (id >> 24) & 0xFFu;;
> > +	preempt_enable();
> > +	return id;
> 
> dont we want to put get_apic_id() into struct genapic instead? We 
> already have ID management there.
> 
> also, we want to unify 32-bit and 64-bit genapic code and just have 
> genapic all across x86.

Long term, I think that makes sense. However, I think that should be a
separate series of patches since there are significant differences between
the 32-bit and 64-bit genapic structs.

--- jack