From ecf46abdd32a35fcd7dfeef72600a065425532b3 Mon Sep 17 00:00:00 2001 From: Gerald Schaefer Date: Fri, 29 May 2015 15:34:51 +0200 Subject: [PATCH] s390/mm: enable gup code for NUMA Force get_user_page() to take the slow path for NUMA migration pages. Signed-off-by: Gerald Schaefer Signed-off-by: Martin Schwidefsky --- arch/s390/mm/gup.c | 10 ++++++++++ 1 file changed, 10 insertions(+) diff --git a/arch/s390/mm/gup.c b/arch/s390/mm/gup.c index 1eb41bb3010c..12bbf0e8478f 100644 --- a/arch/s390/mm/gup.c +++ b/arch/s390/mm/gup.c @@ -30,6 +30,9 @@ static inline int gup_pte_range(pmd_t *pmdp, pmd_t pmd, unsigned long addr, do { pte = *ptep; barrier(); + /* Similar to the PMD case, NUMA hinting must take slow path */ + if (pte_protnone(pte)) + return 0; if ((pte_val(pte) & mask) != 0) return 0; VM_BUG_ON(!pfn_valid(pte_pfn(pte))); @@ -125,6 +128,13 @@ static inline int gup_pmd_range(pud_t *pudp, pud_t pud, unsigned long addr, if (pmd_none(pmd) || pmd_trans_splitting(pmd)) return 0; if (unlikely(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_protnone(pmd)) + return 0; if (!gup_huge_pmd(pmdp, pmd, addr, next, write, pages, nr)) return 0; -- GitLab