On Thu 25-10-18 11:53:34, Anshuman Khandual wrote: > > > On 10/24/2018 07:28 PM, Michal Hocko wrote: > > On Wed 24-10-18 15:56:39, Michal Hocko wrote: > >> On Tue 23-10-18 18:31:59, Anshuman Khandual wrote: > >>> Architectures like arm64 have HugeTLB page sizes which are different than > >>> generic sizes at PMD, PUD, PGD level and implemented via contiguous bits. > >>> At present these special size HugeTLB pages cannot be identified through > >>> macros like (PMD|PUD|PGDIR)_SHIFT and hence chosen not be migrated. > >>> > >>> Enabling migration support for these special HugeTLB page sizes along with > >>> the generic ones (PMD|PUD|PGD) would require identifying all of them on a > >>> given platform. A platform specific hook can precisely enumerate all huge > >>> page sizes supported for migration. Instead of comparing against standard > >>> huge page orders let hugetlb_migration_support() function call a platform > >>> hook arch_hugetlb_migration_support(). Default definition for the platform > >>> hook maintains existing semantics which checks standard huge page order. > >>> But an architecture can choose to override the default and provide support > >>> for a comprehensive set of huge page sizes. > >>> > >>> Reviewed-by: Naoya Horiguchi <n-horiguchi@xxxxxxxxxxxxx> > >>> Signed-off-by: Anshuman Khandual <anshuman.khandual@xxxxxxx> > >> > >> Acked-by: Michal Hocko <mhocko@xxxxxxx> > > > > fat fingers here, should be mhocko@xxxxxxxx of course. > > Sure no problems. As we had discussed earlier and agreed to keep the previous > patch "mm/hugetlb: Enable PUD level huge page migration" separate and not fold > into this one, I will assume your ACK on it as well unless your disagree. OK with me. -- Michal Hocko SUSE Labs
