On Tue, Nov 25, 2014 at 03:01:16AM +0000, Naoya Horiguchi wrote: > On Wed, Nov 05, 2014 at 04:49:36PM +0200, Kirill A. Shutemov wrote: > > FOLL_SPLIT is used only in two places: migration and s390. > > > > Let's replace it with explicit split and remove FOLL_SPLIT. > > > > Signed-off-by: Kirill A. Shutemov <[email protected]> > > --- > ... > > @@ -1246,6 +1246,11 @@ static int do_move_page_to_node_array(struct > > mm_struct *mm, > > if (!page) > > goto set_status; > > > > + if (PageTransHuge(page) && split_huge_page(page)) { > > + err = -EBUSY; > > + goto set_status; > > + } > > + > > This check makes split_huge_page() be called for hugetlb pages, which > triggers BUG_ON. So could you do this after if (PageHuge) block below? > And I think that we have "Node already in the right place" check afterward, > so I hope that moving down this check also helps us reduce thp splitting.
It makes sense. Thanks for report. Other problem here is that we need to goto put_and_set, not set_status :-/ -- Kirill A. Shutemov -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
