Re: [PATCH/RFC v2] introduce ARCH_CAN_UNALIGNED_ACCESS Kconfig symbol
From: John W. Linville <hidden>
Date: 2008-03-20 22:08:23
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On Thu, Mar 20, 2008 at 10:21:46PM +0100, Johannes Berg wrote:
quoted
I think you're semantically testing the wrong thing. It's not if unaligned accesses are supported, it's if they are efficient enough or not. For example, sparc64 fully handles unaligned accesses but taking the trap to fix it up is slow. So sparc64 "can" handle unaligned accesses, but whether we want to set this symbol or not is another matter.Yeah, good point. Should I rename it to HAVE_EFFICIENT_UNALIGNED_ACCESS or similar? Or have it defined as some sort of number so you can make actually make tradeoffs? Like Dave Woodhouse suggested at some point to have get_unaligned() take an argument that indicates the probability...
Ugh...that sounds like premature optimization to me... While I think Dave has a point, I don't think you should labor the word choice too much. Try to document it as clearly as possible and hope for the best -- I hear that the arch maintainers are top notch! :-) John -- John W. Linville linville-2XuSBdqkA4R54TAoqtyWWQ@public.gmane.org -- To unsubscribe from this list: send the line "unsubscribe linux-wireless" in the body of a message to majordomo-u79uwXL29TY76Z2rM5mHXA@public.gmane.org More majordomo info at http://vger.kernel.org/majordomo-info.html