Re: replace "memset(...,0,PAGE_SIZE)" calls with "clear_page()"?

From: Arjan van de Ven
Date: Sat Dec 30 2006 - 17:46:16 EST



> i don't see how that can be true, given that most of the definitions
> of the clear_page() macro are simply invocations of memset(). see for
> yourself:

*MOST*. Not all.
For example an SSE version will at least assume 16 byte alignment, etc
etc.

clear_page() is supposed to be for full real pages only... for example
it allows the architecture to optimize for alignment, cache aliasing etc
etc. (and if there are cpus that get a "clear an entire page"
instruction.... there has been hardware like that in the past, even on
x86, just it's no longer sold afaik)

--
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