Re: HugeTLB vs. SH3 cpu

From: Dave Hansen
Date: Wed Apr 02 2008 - 20:06:25 EST


On Wed, 2008-04-02 at 15:55 -0700, Nishanth Aravamudan wrote:
> On 02.04.2008 [17:04:48 +0900], Paul Mundt wrote:
> > On Tue, Apr 01, 2008 at 04:26:14PM -0700, Nish Aravamudan wrote:
> > Sorting out the mess noted by Adrian is pretty trivial with a
> > HAVE_HUGETLB_PAGE. How about this?
>
> I'm confused, isn't the following simpler fix equivalent?
>
> Fix sh3 build with HUGETLBFS=y. Only SH4 and SH5 actually support
> HUGETLB_PAGE (which HUGETLBFS depends on).
>
> Signed-off-by: Nishanth Aravamudan <nacc@xxxxxxxxxx>
>
> diff --git a/fs/Kconfig b/fs/Kconfig
> index d731282..1981f8e 100644
> --- a/fs/Kconfig
> +++ b/fs/Kconfig
> @@ -978,7 +978,7 @@ config TMPFS_POSIX_ACL
>
> config HUGETLBFS
> bool "HugeTLB file system support"
> - depends on X86 || IA64 || PPC64 || SPARC64 || (SUPERH && MMU) || BROKEN
> + depends on X86 || IA64 || PPC64 || SPARC64 || ((CPU_SH4 || CPU_SH5) && MMU) || BROKEN

Yeah, that's equivalent. But, you have to draw the line at some point
on how complex that "depends on" is going to get. I think you each have
unique pain tolerances. :)

Personally, I kinda prefer to break it out per-arch, because that SUPERH
logic is getting a bit screwy.

You could also do something like this:

> config HUGETLBFS
> bool "HugeTLB file system support"
> - depends on X86 || IA64 || PPC64 || SPARC64 || (SUPERH && MMU) || BROKEN
> + depends on X86 || IA64 || PPC64 || SPARC64 || SUPERH_HUGETLBFS || BROKEN

And then:

config SUPERH_HUGETLBFS
def_bool y
depends on (CPU_SH4 || CPU_SH5) && MMU

on the arch-specific side.

-- Dave

--
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/