Re: [PATCH 05/16] page-flags: define behavior of FS/IO-related flags on compound pages
From: Hugh Dickins <hughd@google.com>
Date: 2015-03-25 18:57:10
Also in:
alsa-devel, lkml
On Wed, 25 Mar 2015, Kirill A. Shutemov wrote:
quoted hunk ↗ jump to hunk
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, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: <a href=mailto:"dont@kvack.org"> email@kvack.org </a>