Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S965391AbcCJFd6 (ORCPT ); Thu, 10 Mar 2016 00:33:58 -0500 Received: from e28smtp01.in.ibm.com ([125.16.236.1]:44837 "EHLO e28smtp01.in.ibm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751571AbcCJFd4 (ORCPT ); Thu, 10 Mar 2016 00:33:56 -0500 X-IBM-Helo: d28relay04.in.ibm.com X-IBM-MailFrom: khandual@linux.vnet.ibm.com X-IBM-RcptTo: linux-kernel@vger.kernel.org Message-ID: <56E10738.7020204@linux.vnet.ibm.com> Date: Thu, 10 Mar 2016 11:03:44 +0530 From: Anshuman Khandual User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:31.0) Gecko/20100101 Thunderbird/31.7.0 MIME-Version: 1.0 To: "Aneesh Kumar K.V" , 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, mgorman@techsingularity.net, akpm@linux-foundation.org Subject: Re: [RFC 4/9] powerpc/mm: Split huge_pte_alloc function for BOOK3S 64K References: <1457525450-4262-1-git-send-email-khandual@linux.vnet.ibm.com> <1457525450-4262-4-git-send-email-khandual@linux.vnet.ibm.com> <878u1r1l4m.fsf@linux.vnet.ibm.com> In-Reply-To: <878u1r1l4m.fsf@linux.vnet.ibm.com> Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 7bit X-TM-AS-MML: disable x-cbid: 16031005-4790-0000-0000-00000DD370D6 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1223 Lines: 29 On 03/10/2016 01:25 AM, Aneesh Kumar K.V wrote: > Anshuman Khandual writes: > >> > [ text/plain ] >> > From: root >> > >> > Currently the 'huge_pte_alloc' function has two versions, one for the >> > BOOK3S and the other one for the BOOK3E platforms. This change splits >> > the BOOK3S version into two parts, one for the 4K page size based >> > implementation and the other one for the 64K page sized implementation. >> > This change is one of the prerequisites towards enabling GENERAL_HUGETLB >> > implementation for BOOK3S 64K based huge pages. > I really wish we reduce #ifdefs in C code and start splitting hash > and nonhash code out where ever we can. Okay but here we are only dealing with 64K and 4K configs inside book3s. I guess it covers both hash and no hash implementations. Not sure if I got it correctly. > > What we really want here is a book3s version and in book3s version use > powerpc specific huge_pte_alloc only if GENERAL_HUGETLB was not defined. got it. > Don't limit it to 64k linux page size. We should select between powerpc > specific implementation and generic code using GENERAL_HUGETLB define. Got it. will try.