On 2024/3/14 22:33, Matthew Wilcox wrote:
> On Thu, Mar 14, 2024 at 11:26:17AM +0100, David Hildenbrand wrote:
>> Should we include this hunk:
>>
>> diff --git a/mm/debug.c b/mm/debug.c
>> index c1c1a6a484e4c..f521e17150a10 100644
>> --- a/mm/debug.c
>> +++ b/mm/debug.c
>> @@ -63,7 +63,8 @@ static void __dump_folio(struct folio *folio, struct page *page,
>> * encode own info, and we must avoid calling page_folio() again.
>> */
>> if (!folio_test_slab(folio)) {
>> - mapcount = atomic_read(&page->_mapcount) + 1;
>> + if (!folio_test_hugetlb(folio))
>> + mapcount = atomic_read(&page->_mapcount) + 1;
>> if (folio_test_large(folio))
>> mapcount += folio_entire_mapcount(folio);
>> }
>>
>> Apart from that, LGTM
>
> I actually want to do a bit more here ...
>
> +++ b/mm/debug.c
> @@ -58,15 +58,10 @@ static void __dump_folio(struct folio *folio, struct page *page,
> int mapcount = 0;
> char *type = "";
>
> - /*
> - * page->_mapcount space in struct page is used by slab pages to
> - * encode own info, and we must avoid calling page_folio() again.
> - */
> - if (!folio_test_slab(folio)) {
> + if (!page_has_type(page)) {
> mapcount = atomic_read(&page->_mapcount) + 1;
> - if (folio_test_large(folio))
> - mapcount += folio_entire_mapcount(folio);
> - }
> + if (folio_test_large(folio))
> + mapcount += folio_entire_mapcount(folio);
Why folio_test_large is not within the "if (!page_has_type(page))" block? I think a slab page could also be large folio.
Or am I miss something?
Thanks.
