From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753525AbdHKQMg (ORCPT ); Fri, 11 Aug 2017 12:12:36 -0400 Received: from userp1040.oracle.com ([156.151.31.81]:46025 "EHLO userp1040.oracle.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752901AbdHKQMf (ORCPT ); Fri, 11 Aug 2017 12:12:35 -0400 Subject: Re: [v6 13/15] mm: stop zeroing memory during allocation in vmemmap To: Michal Hocko Cc: linux-kernel@vger.kernel.org, sparclinux@vger.kernel.org, linux-mm@kvack.org, linuxppc-dev@lists.ozlabs.org, linux-s390@vger.kernel.org, linux-arm-kernel@lists.infradead.org, x86@kernel.org, kasan-dev@googlegroups.com, borntraeger@de.ibm.com, heiko.carstens@de.ibm.com, davem@davemloft.net, willy@infradead.org, ard.biesheuvel@linaro.org, will.deacon@arm.com, catalin.marinas@arm.com, sam@ravnborg.org References: <1502138329-123460-1-git-send-email-pasha.tatashin@oracle.com> <1502138329-123460-14-git-send-email-pasha.tatashin@oracle.com> <20170811130449.GL30811@dhcp22.suse.cz> From: Pasha Tatashin Message-ID: <16bdfd76-d28a-0732-9a15-29cc373e1236@oracle.com> Date: Fri, 11 Aug 2017 12:11:24 -0400 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:52.0) Gecko/20100101 Thunderbird/52.2.1 MIME-Version: 1.0 In-Reply-To: <20170811130449.GL30811@dhcp22.suse.cz> Content-Type: text/plain; charset=utf-8; format=flowed Content-Language: en-US Content-Transfer-Encoding: 7bit X-Source-IP: userv0022.oracle.com [156.151.31.74] Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 08/11/2017 09:04 AM, Michal Hocko wrote: > On Mon 07-08-17 16:38:47, Pavel Tatashin wrote: >> Replace allocators in sprase-vmemmap to use the non-zeroing version. So, >> we will get the performance improvement by zeroing the memory in parallel >> when struct pages are zeroed. > > First of all this should be probably merged with the previous patch. The > I think vmemmap_alloc_block would be better to split up into > __vmemmap_alloc_block which doesn't zero and vmemmap_alloc_block which > does zero which would reduce the memset callsites and it would make it > slightly more robust interface. Ok, I will add: vmemmap_alloc_block_zero() call, and merge this and the previous patches together.