Naoya Horiguchi wrote: > Thp related code also uses per process mm->page_table_lock now. So making > it fine-grained can provide better performance. > > This patch makes thp support split page table lock which makes us use > page->ptl of the pages storing "pmd_trans_huge" pmds. Hm. So, you use page->ptl only when you deal with thp pages, otherwise mm->page_table_lock, right? It looks inconsistent to me. Does it mean we have to take both locks on split and collapse paths? I'm not sure if it's safe to take only page->ptl for alloc path. Probably not. Why not to use new locking for pmd everywhere? -- Kirill A. Shutemov -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@xxxxxxxxx. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: <a href=mailto:"dont@xxxxxxxxx";> email@xxxxxxxxx </a>