On 15.03.21 11:27, Oscar Salvador wrote:
On Mon, Mar 15, 2021 at 10:06:40AM +0100, David Hildenbrand wrote:BTW, I stumbled yesterday over alloc_contig_pages()->pfn_range_valid_contig(): if (page_count(page) > 0) rerurn false; if (PageHuge(page)) return false; As used by memtrace and for gigantic pages. We can now a) Drop these check completely, as it's best-effort only and racy. alloc_contig_pages()/alloc_contig_range() will handle it properly. b) Similarly, check for gigantic pages and/or movability/migratability. Dropping both checks might be the right thing to do: might significantly increase allocation chances -- as we actually end up migrating busy pages ...Oh, sorry David, my mail client tricked me and I did not see this till now. I will have a look, but I would like to collect some more feedback from all pieces before going any further and write a new version. Vlastimil patch#1 and patch#2 and he was ok with them, but let see what others think as well.
Planning on having a detailed look at the patches. Fairly busy though ... :(
-- Thanks, David / dhildenb
