On 10/19/2018 07:29 AM, Naoya Horiguchi wrote: > On Fri, Oct 12, 2018 at 09:29:56AM +0530, Anshuman Khandual wrote: >> During huge page allocation it's migratability is checked to determine if >> it should be placed under movable zones with GFP_HIGHUSER_MOVABLE. But the >> movability aspect of the huge page could depend on other factors than just >> migratability. Movability in itself is a distinct property which should not >> be tied with migratability alone. >> >> This differentiates these two and implements an enhanced movability check >> which also considers huge page size to determine if it is feasible to be >> placed under a movable zone. At present it just checks for gigantic pages >> but going forward it can incorporate other enhanced checks. > > (nitpicking...) > The following code just checks hugepage_migration_supported(), so maybe > s/Movability/Migratability/ is expected in the comment? > > static int unmap_and_move_huge_page(...) > { > ... > /* > * Movability of hugepages depends on architectures and hugepage size. > * This check is necessary because some callers of hugepage migration > * like soft offline and memory hotremove don't walk through page > * tables or check whether the hugepage is pmd-based or not before > * kicking migration. > */ > if (!hugepage_migration_supported(page_hstate(hpage))) { > Sure, will update this patch only unless other changes are suggested.