From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932420AbcCIMMO (ORCPT ); Wed, 9 Mar 2016 07:12:14 -0500 Received: from e23smtp03.au.ibm.com ([202.81.31.145]:40891 "EHLO e23smtp03.au.ibm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753568AbcCIML4 (ORCPT ); Wed, 9 Mar 2016 07:11:56 -0500 X-IBM-Helo: d23dlp01.au.ibm.com X-IBM-MailFrom: khandual@linux.vnet.ibm.com X-IBM-RcptTo: linux-kernel@vger.kernel.org From: Anshuman Khandual To: linux-mm@kvack.org, linux-kernel@vger.kernel.org, linuxppc-dev@lists.ozlabs.org Cc: hughd@google.com, kirill@shutemov.name, n-horiguchi@ah.jp.nec.com, akpm@linux-foundation.org, mgorman@techsingularity.net, aneesh.kumar@linux.vnet.ibm.com, mpe@ellerman.id.au Subject: [RFC 1/9] mm/hugetlb: Make GENERAL_HUGETLB functions PGD implementation aware Date: Wed, 9 Mar 2016 17:40:42 +0530 Message-Id: <1457525450-4262-1-git-send-email-khandual@linux.vnet.ibm.com> X-Mailer: git-send-email 2.1.0 X-TM-AS-MML: disable X-Content-Scanned: Fidelis XPS MAILER x-cbid: 16030912-0009-0000-0000-0000032C1C8F Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Currently both the ARCH_WANT_GENERAL_HUGETLB functions 'huge_pte_alloc' and 'huge_pte_offset' dont take into account huge page implementation at the PGD level. With addition of PGD awareness into these functions, more architectures like POWER which also implements huge pages at PGD level (along with PMD level), can use ARCH_WANT_GENERAL_HUGETLB option. Signed-off-by: Anshuman Khandual --- mm/hugetlb.c | 9 +++++++++ 1 file changed, 9 insertions(+) diff --git a/mm/hugetlb.c b/mm/hugetlb.c index 01f2b48..a478b7b 100644 --- a/mm/hugetlb.c +++ b/mm/hugetlb.c @@ -4251,6 +4251,11 @@ pte_t *huge_pte_alloc(struct mm_struct *mm, pte_t *pte = NULL; pgd = pgd_offset(mm, addr); + if (sz == PGDIR_SIZE) { + pte = (pte_t *)pgd; + goto huge_pgd; + } + pud = pud_alloc(mm, pgd, addr); if (pud) { if (sz == PUD_SIZE) { @@ -4263,6 +4268,8 @@ pte_t *huge_pte_alloc(struct mm_struct *mm, pte = (pte_t *)pmd_alloc(mm, pud, addr); } } + +huge_pgd: BUG_ON(pte && !pte_none(*pte) && !pte_huge(*pte)); return pte; @@ -4276,6 +4283,8 @@ pte_t *huge_pte_offset(struct mm_struct *mm, unsigned long addr) pgd = pgd_offset(mm, addr); if (pgd_present(*pgd)) { + if (pgd_huge(*pgd)) + return (pte_t *)pgd; pud = pud_offset(pgd, addr); if (pud_present(*pud)) { if (pud_huge(*pud)) -- 2.1.0