Re: replace "memset(...,0,PAGE_SIZE)" calls with "clear_page()"?
From: Denis Vlasenko
Date: Sat Dec 30 2006 - 15:51:10 EST
On Friday 29 December 2006 07:16, Robert P. J. Day wrote:
> is there some reason there are so many calls of the form
> memset(addr, 0, PAGE_SIZE)
> rather than the apparently equivalent invocation of
> the majority of architectures appear to define the clear_page() macro
> in their include/<arch>/page.h header file, but not entirely
> identically, and in some cases that definition is conditional, as with
> #ifdef CONFIG_X86_USE_3DNOW
> #define clear_page(page) mmx_clear_page((void *)(page))
> #define clear_page(page) memset((void *)(page), 0, PAGE_SIZE)
> should it perhaps be part of the CodingStyle doc to use the
> clear_page() macro rather than an explicit call to memset()? (and
> should all architectures be required to define that macro?)
clear_page assumes that given address is page aligned, I think.
It may fail if you feed it with misaligned region's address.
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/