Re: [PATCH] Centralise definitions of sector_t and blkcnt_t

[Jan Engelhardt <jengelh@linux01.gwdg.de>]

On Dec 4 2006 19:44, Linus Torvalds wrote:
>
>[...]allow even 64-bit architectures to say that they only want 32-bit 
>sector_t's and page indexes [...]
>
>I don't know how big a deal it is, but I could imagine that we could 
>actually save memory in a smaller "struct page", for example, on 64bit 
>architectures by just using a 4-byte index.
>
>For now, the !64BIT makes sense simply because a 64-bit architecture 
>probably doesn't care, and might as well just use 64 bits anyway (ie you 
>tend to have tons of memory there anyway). And I suspect it doesn't 
>actually even help on 64-bits due to structure alignment etc issues, but 
>am too lazy to go check.

sparc could benefit from this (someone go correct me if I am wrong).
Not only in struct sizes, but maybe also a little in execution time.


	-`J'
-- 
-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@vger.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/