Re: [PATCH] i386-pda: Initialize the PDA early, before any C code runs.

[Ingo Molnar <mingo@elte.hu>]

* Jeremy Fitzhardinge <jeremy@goop.org> wrote:

> Jeremy Fitzhardinge wrote:
> >Not sure, but I think this replicates the behaviour of the original 
> >code (ie, INIT_THREAD_INFO initializes cpu to 0, so smp_processor_id 
> >will return 0).  Hm, Voyager will probably need a little patch to 
> >update the the PDA cpu_number properly in smp_setup_processor_id().
> 
> Something like this, perhaps:
> 
> Subject: set the boot CPU number in the boot_pda
> 
> Signed-off-by: Jeremy Fitzhardinge <jeremy@xensource.com>

> +++ b/arch/i386/mach-voyager/voyager_smp.c	Mon Sep 11 16:34:09 2006 

> smp_setup_processor_id(void)
> {
> 	current_thread_info()->cpu = hard_smp_processor_id();
> -}
> +	write_pda(cpu_number, hard_smp_processor_id());
> +}

yeah. On all other x86 SMP platforms we use the logical APIC ID 0 for 
the boot CPU. (the physical ID might be different, but that doesnt 
matter)

NOTE: you'll also need to patch smp_voyager.c:find_smp_config(), where 
it sets current_thread_info()->cpu to boot_cpu_id.

	Ingo