From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-pg0-f72.google.com (mail-pg0-f72.google.com [74.125.83.72]) by kanga.kvack.org (Postfix) with ESMTP id 43D276B037C for ; Thu, 10 Aug 2017 13:11:06 -0400 (EDT) Received: by mail-pg0-f72.google.com with SMTP id y190so13069202pgb.3 for ; Thu, 10 Aug 2017 10:11:06 -0700 (PDT) Received: from foss.arm.com (foss.arm.com. [217.140.101.70]) by mx.google.com with ESMTP id z12si4221810pgc.584.2017.08.10.10.11.04 for ; Thu, 10 Aug 2017 10:11:05 -0700 (PDT) From: Punit Agrawal Subject: [PATCH v6 6/9] arm64: hugetlb: Override huge_pte_clear() to support contiguous hugepages Date: Thu, 10 Aug 2017 18:09:03 +0100 Message-Id: <20170810170906.30772-7-punit.agrawal@arm.com> In-Reply-To: <20170810170906.30772-1-punit.agrawal@arm.com> References: <20170810170906.30772-1-punit.agrawal@arm.com> Sender: owner-linux-mm@kvack.org List-ID: To: will.deacon@arm.com, catalin.marinas@arm.com Cc: Punit Agrawal , linux-mm@kvack.org, steve.capper@arm.com, linux-arm-kernel@lists.infradead.org, mark.rutland@arm.com, David Woods The default huge_pte_clear() implementation does not clear contiguous page table entries when it encounters contiguous hugepages that are supported on arm64. Fix this by overriding the default implementation to clear all the entries associated with contiguous hugepages. Signed-off-by: Punit Agrawal Cc: David Woods --- arch/arm64/include/asm/hugetlb.h | 6 +++++- arch/arm64/mm/hugetlbpage.c | 36 ++++++++++++++++++++++++++++++++++++ 2 files changed, 41 insertions(+), 1 deletion(-) diff --git a/arch/arm64/include/asm/hugetlb.h b/arch/arm64/include/asm/hugetlb.h index 793bd73b0d07..df8c0aea0917 100644 --- a/arch/arm64/include/asm/hugetlb.h +++ b/arch/arm64/include/asm/hugetlb.h @@ -18,7 +18,6 @@ #ifndef __ASM_HUGETLB_H #define __ASM_HUGETLB_H -#include #include static inline pte_t huge_ptep_get(pte_t *ptep) @@ -82,6 +81,11 @@ extern void huge_ptep_set_wrprotect(struct mm_struct *mm, unsigned long addr, pte_t *ptep); extern void huge_ptep_clear_flush(struct vm_area_struct *vma, unsigned long addr, pte_t *ptep); +extern void huge_pte_clear(struct mm_struct *mm, unsigned long addr, + pte_t *ptep, unsigned long sz); +#define huge_pte_clear huge_pte_clear + +#include #ifdef CONFIG_ARCH_HAS_GIGANTIC_PAGE static inline bool gigantic_page_supported(void) { return true; } diff --git a/arch/arm64/mm/hugetlbpage.c b/arch/arm64/mm/hugetlbpage.c index 09e79785c019..b69430a04e87 100644 --- a/arch/arm64/mm/hugetlbpage.c +++ b/arch/arm64/mm/hugetlbpage.c @@ -68,6 +68,30 @@ static int find_num_contig(struct mm_struct *mm, unsigned long addr, return CONT_PTES; } +static inline int num_contig_ptes(unsigned long size, size_t *pgsize) +{ + int contig_ptes = 0; + + *pgsize = size; + + switch (size) { + case PUD_SIZE: + case PMD_SIZE: + contig_ptes = 1; + break; + case CONT_PMD_SIZE: + *pgsize = PMD_SIZE; + contig_ptes = CONT_PMDS; + break; + case CONT_PTE_SIZE: + *pgsize = PAGE_SIZE; + contig_ptes = CONT_PTES; + break; + } + + return contig_ptes; +} + /* * Changing some bits of contiguous entries requires us to follow a * Break-Before-Make approach, breaking the whole contiguous set @@ -260,6 +284,18 @@ pte_t arch_make_huge_pte(pte_t entry, struct vm_area_struct *vma, return entry; } +void huge_pte_clear(struct mm_struct *mm, unsigned long addr, + pte_t *ptep, unsigned long sz) +{ + int i, ncontig; + size_t pgsize; + + ncontig = num_contig_ptes(sz, &pgsize); + + for (i = 0; i < ncontig; i++, addr += pgsize, ptep++) + pte_clear(mm, addr, ptep); +} + pte_t huge_ptep_get_and_clear(struct mm_struct *mm, unsigned long addr, pte_t *ptep) { -- 2.13.2 -- 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: email@kvack.org