Re: [patch] x86: allow ZONE_DMA to be configurable

["H. Peter Anvin" <hpa@zytor.com>]

Yes, those exceptions should be factored out and put under a separate suboption... CONFIG_SMALLMEM or so.

"David Rientjes" <rientjes@google.com> wrote:

>On Fri, 15 Oct 2010, Ingo Molnar wrote:
>
>> Also, historically we have not been moving kconfig variables in and out 
>> of CONFIG_EMBEDDED all that often for this to be an issue in the future.
>> 
>
>There are also kconfig options that depend on EMBEDDED that are actually 
>for embedded or very small systems; the most obvious example that comes to 
>mind is SLOB.  Simply doing an s/EMBEDDED/EXPERT/ conversion seems 
>appropriate given the semantics for the option that Peter gave, but there 
>are exceptions that will need to be identified, and I think SLOB is one of 
>them.
>
>I don't think we need a kconfig _dependency_ that exists solely to 
>identify other config options for a specific field of hardware, but then 
>we leave a burden for those users to identify the correct options that 
>they need for their configurations that was, I'm assuming, the original 
>intent of CONFIG_EMBEDDED in the first place.  So perhaps we can allow an 
>option for small embedded systems that can "select" other options when 
>enabled but don't have strict "depends" requirements?
>
>I had a thread with Matt Mackall about a year and a half ago on LKML about 
>the meaning of CONFIG_EMBEDDED and its use for the SLOB allocator; it 
>would be much better for us to identify systems with memory limitations 
>that strive to reduce footprint as much as possible to automatically 
>select certain options over others.  I believe we talked about SLOB being 
>the default for systems with under 16MB of memory, but we have limited 
>ability to identify that for the user.

-- 
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