On Thu, 26 Apr 2018 10:27:55 -0400 Zi Yan <zi.yan@xxxxxxxx> wrote: > From: Zi Yan <zi.yan@xxxxxxxxxxxxxx> > > Hi all, > > THP migration is only enabled on x86_64 with a special > ARCH_ENABLE_THP_MIGRATION macro. This patchset enables THP migration for > all architectures that uses transparent hugepage, so that special macro can > be dropped. Instead, THP migration is enabled/disabled via > /sys/kernel/mm/transparent_hugepage/enable_thp_migration. > > I grepped for TRANSPARENT_HUGEPAGE in arch folder and got 9 architectures that > are supporting transparent hugepage. I mechanically add __pmd_to_swp_entry() and > __swp_entry_to_pmd() based on existing __pte_to_swp_entry() and > __swp_entry_to_pte() for all these architectures, except tile which is going to > be dropped. This will not work on s390, the pmd layout is very different from the pte layout. Using __swp_entry/type/offset() on a pmd will go horribly wrong. I currently don't see a chance to make this work for us, so please make/keep this configurable, and do not configure it for s390. Regards, Gerald
