Re: [PATCH v3 2/2] mm/damon: introduce DAMOS filter type hugepage

[SeongJae Park <sj@kernel.org>]

On Mon, 20 Jan 2025 20:23:20 +0100 David Hildenbrand <david@redhat.com> wrote:

> On 20.01.25 20:16, SeongJae Park wrote:
> > On Mon, 20 Jan 2025 19:57:10 +0100 David Hildenbrand <david@redhat.com> wrote:
> > 
> >> On 20.01.25 19:19, Usama Arif wrote:
[...]
> >>> +#if defined(CONFIG_PGTABLE_HAS_HUGE_LEAVES)
> >>> +	case DAMOS_FILTER_TYPE_HUGEPAGE:
> >>> +		matched = folio_size(folio) == HPAGE_PMD_SIZE;
> >>
> >>
> >> Can we directly embed in the name and the comments/docs that we are only
> >> talking about PMD size (both, THP and hugetlb)?
> >>
> >> DAMOS_FILTER_TYPE_PMD_HUGEPAGE or sth. like that.
> > 
> > Nice suggestion, thank you!  And we might later add more filter types for
> > different size huge pages.  What about extending this to handle more general
> > case, though?  That is, we can let the filter receives a range of the folio
> > size to match, like DAMOS_FILTER_TYPE_ADDR does.  Then, the filter could be
> > used for any size of interest.
> 
> That would probably be future proof: either a range or explicitly 
> specified sizes (ranges?).

DAMON supports installing multiple DAMOS filters.  So multiple DAMOS filters
that each matching single range can be used for the multiple sizes or ranges
use case.


Thanks,
SJ

> 
> -- 
> Cheers,
> 
> David / dhildenb