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Date: Tue, 8 Jul 2008 19:35:56 +0200
From: "Vegard Nossum" <vegard.nossum@gmail.com>
To: "Mike Travis" <travis@sgi.com>
Subject: Re: [PATCH 1/1] x86: Change _node_to_cpumask_ptr to return const ptr
Cc: "Ingo Molnar" <mingo@elte.hu>,
       "akpm@linux-foundation.org" <akpm@linux-foundation.org>,
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Hi,

On Tue, Jul 8, 2008 at 7:06 PM, Mike Travis <travis@sgi.com> wrote:
>> (v3 is applied already so Mike please send a delta to v3.)
>>
>>       Ingo
>
> Subject: [PATCH 1/1] x86: Change _node_to_cpumask_ptr to return const ptr
>
>  * Strengthen the return type for the _node_to_cpumask_ptr to be
>    a const pointer.  This adds compiler checking to insure that
>    node_to_cpumask_map[] is not changed inadvertently.
>
> Applies to tip/master with the following patch applied:
>
>        "[PATCH 1/1] x86: Add check for node passed to node_to_cpumask V3"
>
> Signed-off-by: Mike Travis <travis@sgi.com>
> ---
> Note: I did not change node_to_cpumask_ptr() in include/asm-generic/topology.h
>      as node_to_cpumask_ptr_next() does change the cpumask value.

Hmmm. Does it really?

#define node_to_cpumask_ptr_next(v, node)                               \
                          _##v = node_to_cpumask(node)

This doesn't seem to modify it?

Also, isn't it unfortunate to have the same function return
const/non-const depending on your arch/config?


Vegard

-- 
"The animistic metaphor of the bug that maliciously sneaked in while
the programmer was not looking is intellectually dishonest as it
disguises that the error is the programmer's own creation."
	-- E. W. Dijkstra, EWD1036