Re: [PATCH v1 05/11] mm: convert VM_PFNMAP tracking to pfnmap_track() + pfnmap_untrack()

David Hildenbrand
2025-04-28T17:23:29Z

On 28.04.25 18:24, Peter Xu wrote:
> On Mon, Apr 28, 2025 at 06:16:21PM +0200, David Hildenbrand wrote:
>>> Probably due to what config you have. E.g., when I'm looking mine it's
>>> much bigger and already consuming 256B, but it's because I enabled more
>>> things (userfaultfd, lockdep, etc.).
>>
>> Note that I enabled everything that you would expect on a production system
>> (incld. userfaultfd, mempolicy, per-vma locks), so I didn't enable lockep.
>
> I still doubt whether you at least enabled userfaultfd, e.g., your previous
> paste has:
>
> struct vm_userfaultfd_ctx vm_userfaultfd_ctx; /* 176 0 */
>
> Not something that matters.. but just in case you didn't use the expected
> config file you wanted to use..

You're absolutely right. I only briefly rechecked for this purpose here
on my notebook, and only looked for the existence of members, not
expecting that we have confusing stuff like vm_userfaultfd_ctx.

I checked again and the size stays at 192 with allyesconfig and then
disabling debug options.

--
Cheers,

David / dhildenb