On Wed, 25 Mar 2015, Kirill A. Shutemov wrote: > > We only need tail refcounting for THP, so I think this should fix the issue: > > diff --git a/include/linux/mm.h b/include/linux/mm.h > index 4a3a38522ab4..9ab432660adb 100644 > --- a/include/linux/mm.h > +++ b/include/linux/mm.h > @@ -456,7 +456,7 @@ static inline int page_count(struct page *page) > > static inline bool __compound_tail_refcounted(struct page *page) > { > - return !PageSlab(page) && !PageHeadHuge(page); > + return !PageSlab(page) && !PageHeadHuge(page) && PageAnon(page); > } > > /*
Yes, that should be a good fix for the mapcount issue. And no coincidence that it's just what I needed too, when reusing the PG_compound_lock bit: see my 10/24 (which had to rearrange mm.h. not having your 1/16). Hugh -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/