Re: [PATCH v5 07/12] x86/apic: Unify interrupt mode setup for UP system

[Dou Liyang]

Hi Thomas,

At 07/03/2017 02:19 AM, Thomas Gleixner wrote:
> On Fri, 30 Jun 2017, Dou Liyang wrote:
> >  static inline int apic_force_enable(unsigned long addr)
> > diff --git a/arch/x86/kernel/apic/apic.c b/arch/x86/kernel/apic/apic.c
> > index 0601054..9bf7e95 100644
> > --- a/arch/x86/kernel/apic/apic.c
> > +++ b/arch/x86/kernel/apic/apic.c
> > @@ -1198,6 +1198,10 @@ static int __init apic_intr_mode_select(int *upmode)
> >  	}
> >  #endif
> >
> > +#ifdef CONFIG_UP_LATE_INIT
> > +	*upmode = true;
> > +#endif
>
> This is really wrong. The upmode decision, which is required for calling
> apic_bsp_setup() should not happen here, really. As I told you in the
> previous patch, use the return code and then you can make further decisions
> in apic_intr_mode_init().

Really thanks for your detail explaining, I learned more than i read
from books about the programming skill.

> And you do it there w/o any ifdeffery:
>
> static void apic_intr_mode_init(void)
> {
> 	bool upmode = IS_ENABLED(CONFIG_UP_LATE_INIT);
>
> 	switch (....) {
> 	case XXXX:
> 		upmode = true;
> 		....
> 	}
> 	apic_bsp_setup(upmode);
> }

This looks more beautiful than mine.  I will use it in the next version.

Thanks,

	dou.

> Thanks,
>
> 	tglx