From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-pd0-f174.google.com (mail-pd0-f174.google.com [209.85.192.174]) by kanga.kvack.org (Postfix) with ESMTP id CF2E06B0038 for ; Thu, 23 Apr 2015 18:26:22 -0400 (EDT) Received: by pdbqd1 with SMTP id qd1so30275108pdb.2 for ; Thu, 23 Apr 2015 15:26:22 -0700 (PDT) Received: from mga01.intel.com (mga01.intel.com. [192.55.52.88]) by mx.google.com with ESMTP id er5si14452435pbd.38.2015.04.23.15.26.20 for ; Thu, 23 Apr 2015 15:26:22 -0700 (PDT) From: "Luck, Tony" Subject: RE: [PATCH] mm/hugetlb: reduce arch dependent code about huge_pmd_unshare Date: Thu, 23 Apr 2015 22:26:18 +0000 Message-ID: <3908561D78D1C84285E8C5FCA982C28F32A6478B@ORSMSX114.amr.corp.intel.com> References: <1428996566-86763-1-git-send-email-zhenzhang.zhang@huawei.com> <552CC328.9050402@huawei.com> <20150423151118.40c41fb1810f2aaa877163ae@linux-foundation.org> In-Reply-To: <20150423151118.40c41fb1810f2aaa877163ae@linux-foundation.org> Content-Language: en-US Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: quoted-printable MIME-Version: 1.0 Sender: owner-linux-mm@kvack.org List-ID: To: Andrew Morton , Zhang Zhen Cc: Linux MM , Linux Kernel Mailing List , "linux@arm.linux.org.uk" , "catalin.marinas@arm.com" , "james.hogan@imgtec.com" , "ralf@linux-mips.org" , "benh@kernel.crashing.org" , "schwidefsky@de.ibm.com" , "cmetcalf@ezchip.com" , David Rientjes , "James.Yang@freescale.com" , "aneesh.kumar@linux.vnet.ibm.com" > Memory fails me. Why do some architectures (arm, arm64, x86_64) want > huge_pmd_[un]share() while other architectures (ia64, tile, mips, > powerpc, metag, sh, s390) do not? Potentially laziness/ignorance-of-feature? It looks like this feature star= ted on x86_64 and then spread to arm*. Huge pages are weird on ia64 in that they have to be in a specific range of= virtual addresses (region 4). But I don't see why that would prevent sharing pmd's. -Tony -- 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