Re: [PATCH] hugetlb: Provide a default HPAGE_SHIFT if !CONFIG_HUGETLB_PAGE

[David Daney <ddaney.cavm@gmail.com>]

On 11/16/2011 01:32 PM, David Rientjes wrote:
> On Wed, 16 Nov 2011, David Daney wrote:
>
>> From: David Daney<david.daney@cavium.com>
>>
>> This is required now to get MIPS kernels to compile with
>> !CONFIG_HUGETLB_PAGE.
>>
>
> Why?

I should have been more specific.  The failure is in Ralf's 
mips-for-linux-next branch.

>  Apparently there's some config option you've enabled that is causing
> it to fail but I can't find it.  defconfig works fine on my mips
> crosscompiler and allyesconfig is borked already in other ways.

Please look in the mips-for-linux-next branch.

>
> This is definitely the wrong fix, anyway, and it would require a change to
> arch/mips/include/asm/page.h instead since it's localized to mips,

No, all we are doing is supplying a dummy definition for HPAGE_SHIFT as 
we currently have for HPAGE_SIZE and HPAGE_MASK.


> so nack.
>
>> Signed-off-by: David Daney<david.daney@cavium.com>
>> ---
>>   include/linux/hugetlb.h |    1 +
>>   1 files changed, 1 insertions(+), 0 deletions(-)
>>
>> diff --git a/include/linux/hugetlb.h b/include/linux/hugetlb.h
>> index 19644e0..746d543 100644
>> --- a/include/linux/hugetlb.h
>> +++ b/include/linux/hugetlb.h
>> @@ -113,6 +113,7 @@ static inline void copy_huge_page(struct page *dst, struct page *src)
>>   #ifndef HPAGE_MASK
>>   #define HPAGE_MASK	PAGE_MASK		/* Keep the compiler happy */
>>   #define HPAGE_SIZE	PAGE_SIZE

Why didn't you NACK the addition of these two lines too?

Following your logic, we should remove these and patch up all the 
architecture specific files instead.

David Daney

>> +#define HPAGE_SHIFT	PAGE_SHIFT
>>   #endif
>>
>>   #endif /* !CONFIG_HUGETLB_PAGE */
>