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Date: Wed, 30 Jan 2008 13:57:31 -0800
From: Mike Travis <travis@sgi.com>
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To: Ingo Molnar <mingo@elte.hu>
Subject: Re: [PATCH 2/6] percpu: Change Kconfig to HAVE_SETUP_PER_CPU_AREA
	linux-2.6.git
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Cc: Tony Luck <tony.luck@intel.com>, linux-ia64@vger.kernel.org,
	linuxppc-dev@ozlabs.org, Sam Ravnborg <sam@ravnborg.org>,
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Ingo Molnar wrote:
> * travis@sgi.com <travis@sgi.com> 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