From 1dc954bd2f85144b9a2959139d41a5f6b9b34712 Mon Sep 17 00:00:00 2001 From: "Aneesh Kumar K.V" Date: Wed, 2 Apr 2014 21:37:39 +0530 Subject: [PATCH] powerpc/mm: NUMA pte should be handled via slow path in get_user_pages_fast() We need to handle numa pte via the slow path Signed-off-by: Aneesh Kumar K.V Signed-off-by: Benjamin Herrenschmidt --- arch/powerpc/mm/gup.c | 13 +++++++++++++ 1 file changed, 13 insertions(+) diff --git a/arch/powerpc/mm/gup.c b/arch/powerpc/mm/gup.c index c5f734e20b0f..d8746684f606 100644 --- a/arch/powerpc/mm/gup.c +++ b/arch/powerpc/mm/gup.c @@ -36,6 +36,11 @@ static noinline int gup_pte_range(pmd_t pmd, unsigned long addr, do { pte_t pte = ACCESS_ONCE(*ptep); struct page *page; + /* + * Similar to the PMD case, NUMA hinting must take slow path + */ + if (pte_numa(pte)) + return 0; if ((pte_val(pte) & mask) != result) return 0; @@ -75,6 +80,14 @@ static int gup_pmd_range(pud_t pud, unsigned long addr, unsigned long end, if (pmd_none(pmd) || pmd_trans_splitting(pmd)) return 0; if (pmd_huge(pmd) || pmd_large(pmd)) { + /* + * NUMA hinting faults need to be handled in the GUP + * slowpath for accounting purposes and so that they + * can be serialised against THP migration. + */ + if (pmd_numa(pmd)) + return 0; + if (!gup_hugepte((pte_t *)pmdp, PMD_SIZE, addr, next, write, pages, nr)) return 0; -- 2.20.1