Subject: Re: [PATCH 2/6] percpu: Change Kconfig to HAVE_SETUP_PER_CPU_AREA linux-2.6.git

From: Mike Travis <[email-masked]>
Date: Wed, 30 Jan 2008 13:57:31 -0800

Ingo Molnar wrote:
> * [email-masked] <[email-masked]> wrote:
> 
>> Change:
>> 	config ARCH_SETS_UP_PER_CPU_AREA
>> to:
>> 	config HAVE_SETUP_PER_CPU_AREA
> 
> undocumented change:
> 
>>  config ARCH_NO_VIRT_TO_BUS
>> --- a/init/main.c
>> +++ b/init/main.c
>> @@ -380,6 +380,8 @@ static void __init setup_per_cpu_areas(v
>>  
>>  	/* Copy section for each CPU (we discard the original) */
>>  	size = ALIGN(PERCPU_ENOUGH_ROOM, PAGE_SIZE);
>> +	printk(KERN_INFO
>> +	    "PERCPU: Allocating %lu bytes of per cpu data (main)\n", size);
>>  	ptr = alloc_bootmem_pages(size * nr_possible_cpus);
> 
> but looks fine to me.
> 
> 	Ingo

Sorry, I should have noted this.  The primary reason I put this in, is
that if the HAVE_SETUP_PER_CPU_AREA is not set when it should be, then
the incorrect (generic) setup_per_cpu_areas() is used and weird things
happen later on.  The above line documents that PERCPU has been allocated
by init/main.c version of this function in the startup messages.
(Since it's a static function, there is no "duplicate label" error in
the linker.)

Thanks,
Mike