From mboxrd@z Thu Jan 1 00:00:00 1970 From: Andrew Morton Subject: [patch 075/131] arm64/mm: drop __HAVE_ARCH_HUGE_PTEP_GET Date: Wed, 03 Jun 2020 16:00:56 -0700 Message-ID: <20200603230056.4SIR-SKjH%akpm@linux-foundation.org> References: <20200603155549.e041363450869eaae4c7f05b@linux-foundation.org> Reply-To: linux-kernel@vger.kernel.org Return-path: Received: from mail.kernel.org ([198.145.29.99]:43370 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725821AbgFCXA7 (ORCPT ); Wed, 3 Jun 2020 19:00:59 -0400 In-Reply-To: <20200603155549.e041363450869eaae4c7f05b@linux-foundation.org> Sender: mm-commits-owner@vger.kernel.org List-Id: mm-commits@vger.kernel.org To: akpm@linux-foundation.org, anshuman.khandual@arm.com, benh@kernel.crashing.org, borntraeger@de.ibm.com, bp@alien8.de, catalin.marinas@arm.com, dalias@libc.org, davem@davemloft.net, deller@gmx.de, fenghua.yu@intel.com, gor@linux.ibm.com, heiko.carstens@de.ibm.com, hpa@zytor.com, James.Bottomley@HansenPartnership.com, linux-mm@kvack.org, linux@armlinux.org.uk, mike.kravetz@oracle.com, mingo@redhat.com, mm-commits@vger.kernel.org, mpe@ellerman.id.au, palmer@dabbelt.com, paul.walmsley@sifive.com, paulus@samba.org, tglx@linutronix.de, tony.luck@intel.com, torvalds@linux-foundation.org, tsbogend@alpha.franken.de, will@kernel.org, ysato@users.sourceforge.jp From: Anshuman Khandual Subject: arm64/mm: drop __HAVE_ARCH_HUGE_PTEP_GET Patch series "mm/hugetlb: Add some new generic fallbacks", v3. This series adds the following new generic fallbacks. Before that it drops __HAVE_ARCH_HUGE_PTEP_GET from arm64 platform. 1. is_hugepage_only_range() 2. arch_clear_hugepage_flags() After this arm (32 bit) remains the sole platform defining it's own huge_ptep_get() via __HAVE_ARCH_HUGE_PTEP_GET. This patch (of 3): Platform specific huge_ptep_get() is required only when fetching the huge PTE involves more than just dereferencing the page table pointer. This is not the case on arm64 platform. Hence huge_ptep_pte() can be dropped along with it's __HAVE_ARCH_HUGE_PTEP_GET subscription. Before that, it updates the generic huge_ptep_get() with READ_ONCE() which will prevent known page table issues with THP on arm64. Link: http://lkml.kernel.org/r/1588907271-11920-1-git-send-email-anshuman.khandual@arm.com Link: http://lkml.kernel.org/r//1506527369-19535-1-git-send-email-will.deacon@arm.com/ Link: http://lkml.kernel.org/r/1588907271-11920-2-git-send-email-anshuman.khandual@arm.com Signed-off-by: Anshuman Khandual Acked-by: Mike Kravetz Cc: Catalin Marinas Cc: Will Deacon Cc: Benjamin Herrenschmidt Cc: Borislav Petkov Cc: Christian Borntraeger Cc: "David S. Miller" Cc: Fenghua Yu Cc: Heiko Carstens Cc: Helge Deller Cc: "H. Peter Anvin" Cc: Ingo Molnar Cc: "James E.J. Bottomley" Cc: Michael Ellerman Cc: Palmer Dabbelt Cc: Paul Mackerras Cc: Paul Walmsley Cc: Rich Felker Cc: Russell King Cc: Thomas Bogendoerfer Cc: Thomas Gleixner Cc: Tony Luck Cc: Vasily Gorbik Cc: Yoshinori Sato Signed-off-by: Andrew Morton --- arch/arm64/include/asm/hugetlb.h | 6 ------ include/asm-generic/hugetlb.h | 2 +- 2 files changed, 1 insertion(+), 7 deletions(-) --- a/arch/arm64/include/asm/hugetlb.h~arm64-mm-drop-__have_arch_huge_ptep_get +++ a/arch/arm64/include/asm/hugetlb.h @@ -17,12 +17,6 @@ extern bool arch_hugetlb_migration_supported(struct hstate *h); #endif -#define __HAVE_ARCH_HUGE_PTEP_GET -static inline pte_t huge_ptep_get(pte_t *ptep) -{ - return READ_ONCE(*ptep); -}