Re: [PATCH 06/13] mm: pagewalk: Add 'depth' parameter to pte_hole

From: Steven Price
Date: Wed Feb 20 2019 - 09:10:53 EST


On 20/02/2019 11:35, William Kucharski wrote:
>
>
>> On Feb 15, 2019, at 10:02 AM, Steven Price <Steven.Price@xxxxxxx> wrote:
>>
>> The pte_hole() callback is called at multiple levels of the page tables.
>> Code dumping the kernel page tables needs to know what at what depth
>> the missing entry is. Add this is an extra parameter to pte_hole().
>> When the depth isn't know (e.g. processing a vma) then -1 is passed.
>>
>> Note that depth starts at 0 for a PGD so that PUD/PMD/PTE retain their
>> natural numbers as levels 2/3/4.
>
> Nit: Could you add a comment noting this for anyone wondering how to
> calculate the level numbers in the future?

Good point! I'll expand the comment in the header file.

Thanks,

Steve