[PATCH v2 1/3] mm: add vm_normal_lru_pages for LRU handled pages only

[David Hildenbrand]

On 31.03.22 10:53, Christoph Hellwig wrote:
>> -	page = vm_normal_page(vma, addr, pte);
>> +	page = vm_normal_lru_page(vma, addr, pte);
> 
> Why can't this deal with ZONE_DEVICE pages?  It certainly has
> nothing do with a LRU I think.  In fact being able to have
> stats that count say the number of device pages here would
> probably be useful at some point.
> 
> In general I find the vm_normal_lru_page vs vm_normal_page
> API highly confusing.  An explicit check for zone device pages
> in the dozen or so spots that care has a much better documentation
> value, especially if accompanied by comments where it isn't entirely
> obvious.

What's your thought on FOLL_LRU?

-- 
Thanks,

David / dhildenb