Re: [PATCH 00/18] Make common x86 arch area for i386 and x86_64 - Take 2

[Nick Piggin <nickpiggin@yahoo.com.au>]

Ingo Molnar wrote:
> * Linus Torvalds <torvalds@linux-foundation.org> wrote:
> 
> 
>>>symbolic links perhaps? In that case i'd also introduce a common 
>>>naming scheme: x86_early_printk.c - to make sure we know it right 
>>>away that those files are bi-arch.
>>
>>Hey, I know! This is a radical idea, but what if we put the name at 
>>the head of the file, and called it
>>
>>	arch/x86/kernel/early_printk.c
>>
>>instead? Then we could teach each of i386 and x86-64 to include it 
>>from that area, and we could put other shared files under the same 
>>directory hierarchy so that it would be easy to see which ones are 
>>shared?
> 
> 
> that is nice too, but it has some disadvantages as well in practice. For 
> example i often want to see 'everything' that belongs to an arch in just 
> one subdirectory. That way one can grep it for example, instead of 
> having to grep two separate places. Symlinks would be fine for that, but 
> an explicit split not really i think - unless we can get some really 
> significant chunk of code into that hierarchy, so that it makes 
> functional /sense/ to look at it in isolation.
> 
> with the prefix suggestion we can keep these 'shared' files merged in a 
> single, main functional tree (x86_64), but still have them marked in the 
> VFS as being shared. But ... either way is fine to me - no strong 
> feelings, really.

You could do both. Have the x86 directory that Linus suggests for shared
files, then have the build system generate the symlinks for you.

Could have arch/x86_64/kernel/common arch/x86_64/mm/common etc. symlinks.
that point to arch/x86/kernel, arch/x86/mm etc.

This way you know exactly which files are shared and which are not, which
is basically impossible without a grep currently. You also get to do a
single grep of all arch code. Best of both worlds? Or do I miss something?

-- 
SUSE Labs, Novell Inc.
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