On 02/13/23 19:01, Michal Hocko wrote: > On Fri 03-02-23 12:16:04, Mike Kravetz wrote: > [...] > > Unless someone thinks we should move forward, I will not push the code > > for this approach now. It will also be interesting to see if this is > > impacted at all by the outcome of discussions to perhaps redesign > > mapcount. > > Yes, I do agree. We might want to extend page_mapcount documentation a > bit though. The comment is explicit about the order-0 pages but a note > about hugetlb and pmd sharing wouldn't hurt. WDYT? Looks like that comment about 'Mapcount of 0-order page' has been removed in the latest version of page_mapcount(). It would not surprise me if the calls to page_mapcount after which we check for shared PMDs will soon be replaced with calls to folio_mapcount(). Perhaps Matthew has an opinion as to where map counts for hugetlb shared PMDs might be mentioned. -- Mike Kravetz
