From 6fa504835d6969144b2bd3699684dd447c789ba2 Mon Sep 17 00:00:00 2001
From: "Aneesh Kumar K.V" <aneesh.kumar@linux.vnet.ibm.com>
Date: Fri, 30 Mar 2018 17:34:08 +0530
Subject: [PATCH] powerpc/mm/hugetlb: initialize the pagetable cache correctly
for hugetlb
References: bsc#1091800
Patch-mainline: v4.17-rc1
Git-commit: 6fa504835d6969144b2bd3699684dd447c789ba2
With 64k page size, we have hugetlb pte entries at the pmd and pud level for
book3s64. We don't need to create a separate page table cache for that. With 4k
we need to make sure hugepd page table cache for 16M is placed at PUD level
and 16G at the PGD level.
Simplify all these by not using HUGEPD_PD_SHIFT which is confusing for book3s64.
Without this patch, with 64k page size we create pagetable caches with shift
value 10 and 7 which are not used at all.
Fixes: 419df06eea5b ("powerpc: Reduce the PTE_INDEX_SIZE")
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Acked-by: Michal Suchanek <msuchanek@suse.de>
---
arch/powerpc/mm/hugetlbpage.c | 18 +++++++++++++-----
1 file changed, 13 insertions(+), 5 deletions(-)
diff --git a/arch/powerpc/mm/hugetlbpage.c b/arch/powerpc/mm/hugetlbpage.c
index f4153f21d214..99cf86096970 100644
--- a/arch/powerpc/mm/hugetlbpage.c
+++ b/arch/powerpc/mm/hugetlbpage.c
@@ -122,9 +122,6 @@ static int __hugepte_alloc(struct mm_struct *mm, hugepd_t *hpdp,
#if defined(CONFIG_PPC_FSL_BOOK3E) || defined(CONFIG_PPC_8xx)
#define HUGEPD_PGD_SHIFT PGDIR_SHIFT
#define HUGEPD_PUD_SHIFT PUD_SHIFT
-#else
-#define HUGEPD_PGD_SHIFT PUD_SHIFT
-#define HUGEPD_PUD_SHIFT PMD_SHIFT
#endif
/*
@@ -670,15 +667,26 @@ static int __init hugetlbpage_init(void)
shift = mmu_psize_to_shift(psize);
- if (add_huge_page_size(1ULL << shift) < 0)
+#ifdef CONFIG_PPC_BOOK3S_64
+ if (shift > PGDIR_SHIFT)
continue;
-
+ else if (shift > PUD_SHIFT)
+ pdshift = PGDIR_SHIFT;
+ else if (shift > PMD_SHIFT)
+ pdshift = PUD_SHIFT;
+ else
+ pdshift = PMD_SHIFT;
+#else
if (shift < HUGEPD_PUD_SHIFT)
pdshift = PMD_SHIFT;
else if (shift < HUGEPD_PGD_SHIFT)
pdshift = PUD_SHIFT;
else
pdshift = PGDIR_SHIFT;
+#endif
+
+ if (add_huge_page_size(1ULL << shift) < 0)
+ continue;
/*
* if we have pdshift and shift value same, we don't
* use pgt cache for hugepd.
--
2.13.7