From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-2.7 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_GIT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 64FBFC48BD7 for ; Thu, 27 Jun 2019 12:48:44 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 383AC2083B for ; Thu, 27 Jun 2019 12:48:44 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726589AbfF0Msn (ORCPT ); Thu, 27 Jun 2019 08:48:43 -0400 Received: from foss.arm.com ([217.140.110.172]:53638 "EHLO foss.arm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726059AbfF0Msm (ORCPT ); Thu, 27 Jun 2019 08:48:42 -0400 Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.121.207.14]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id DF6942B; Thu, 27 Jun 2019 05:48:41 -0700 (PDT) Received: from p8cg001049571a15.arm.com (unknown [10.163.1.20]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPA id 9656E3F718; Thu, 27 Jun 2019 05:48:38 -0700 (PDT) From: Anshuman Khandual To: linux-mm@kvack.org Cc: Anshuman Khandual , Catalin Marinas , Will Deacon , Mark Rutland , Marc Zyngier , Suzuki Poulose , linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org Subject: [RFC 0/2] arm64/mm: Enable THP migration Date: Thu, 27 Jun 2019 18:18:14 +0530 Message-Id: <1561639696-16361-1-git-send-email-anshuman.khandual@arm.com> X-Mailer: git-send-email 2.7.4 Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org This series enables THP migration without split on arm64 by subscribing to ARCH_ENABLE_THP_MIGRATION. Before that it modifies arm64 platform THP helpers like pmd_present() and pmd_trans_huge() to comply with expected generic MM semantics as concluded from a previous discussion [1]. Initial THP migration and stress tests look good for various THP sizes. I will continue testing this further. But meanwhile looking for some early reviews, feedbacks and suggestions on the approach. This is based on linux-next tree (next-20190626). Question: Instead of directly using PTE_SPECIAL, would it be better to override the same bit as PMD_SPLITTING and create it's associated helpers to make this more clear and explicit ? [1] https://lkml.org/lkml/2018/10/9/220 Cc: Catalin Marinas Cc: Will Deacon Cc: Mark Rutland Cc: Marc Zyngier Cc: Suzuki Poulose Cc: linux-arm-kernel@lists.infradead.org Cc: linux-kernel@vger.kernel.org Anshuman Khandual (2): arm64/mm: Change THP helpers to comply with generic MM semantics arm64/mm: Enable THP migration without split arch/arm64/Kconfig | 4 ++++ arch/arm64/include/asm/pgtable.h | 32 +++++++++++++++++++++++++++++--- 2 files changed, 33 insertions(+), 3 deletions(-) -- 2.7.4