On Fri, Dec 01, 2017 at 09:45:10AM +0100, Michal Hocko wrote: > On Fri 01-12-17 09:31:55, Alexandru Moise wrote: > [...] > > > Subject: mm/madvise: enable soft offline of HugeTLB pages at PUD level > > > > > > Hoping for Kirill review. I wanted additional code comments (I > > > think). mhocko nacked it. > > > > TBH I'd rather give up this one if mhocko feels that there's no point to it. > > Rather drop it than risk adding crap in the kernel :). > > > > It is a bit weird though that currently we have the behavior that on some PPC platforms > > you can migrate 1G hugepages but on x86_64 you cannot. > > I _think_ we can apply this patch in the end. But there is more work to > be done before we can do that. PPC is probably broken in that regard as > well, we just haven't noticed before this got merged. I find the > hwpoison based reasons for merging disputable at best but this is not > serious enough to call for a revert. I am currently working on patches > to make giga pages migratable for real and then we can apply your patch > on top. One way we can approach it is to make architecture code to provide hugepage_migration_supported() with fallback to "return false;" in generic code. It will give us more control on what can be migrated. And we can kill CONFIG_ARCH_ENABLE_HUGEPAGE_MIGRATION. Then we can include new page sizes into migration one-by-one with proper testing. -- 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>
