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=-0.8 required=3.0 tests=DKIM_INVALID,DKIM_SIGNED, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_PASS 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 B7195C43387 for ; Fri, 4 Jan 2019 05:06:01 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 7FF5E21872 for ; Fri, 4 Jan 2019 05:06:01 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="key not found in DNS" (0-bit key) header.d=codeaurora.org header.i=@codeaurora.org header.b="HVy+nOQr"; dkim=fail reason="key not found in DNS" (0-bit key) header.d=codeaurora.org header.i=@codeaurora.org header.b="nzjVoyEg" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726289AbfADFGA (ORCPT ); Fri, 4 Jan 2019 00:06:00 -0500 Received: from smtp.codeaurora.org ([198.145.29.96]:35418 "EHLO smtp.codeaurora.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726000AbfADFGA (ORCPT ); Fri, 4 Jan 2019 00:06:00 -0500 Received: by smtp.codeaurora.org (Postfix, from userid 1000) id 396BF6081B; Fri, 4 Jan 2019 05:05:59 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=codeaurora.org; s=default; t=1546578359; bh=p4hYRBMBz5M+YHHn8pLZuYvTovLuqvtKmAsC8TbXY5g=; h=Date:From:To:Cc:Subject:In-Reply-To:References:From; b=HVy+nOQr9jgSZ+axTEZDpTVcKnKsASg7fgjT5HYmJJ9uE0y8D7Qfr5/TEs5bnhrIP PVYN/v1cwm4UpA10IdZ+EyedDYfen1zWIt+QfXJid7LwBzRoxVXOsnK34sRk+2ghHu iZLounFmFXEc9cTCZ3/BC15Wm5KIyHNBGNNKWWuE= Received: from mail.codeaurora.org (localhost.localdomain [127.0.0.1]) by smtp.codeaurora.org (Postfix) with ESMTP id 7A3876034F; Fri, 4 Jan 2019 05:05:58 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=codeaurora.org; s=default; t=1546578358; bh=p4hYRBMBz5M+YHHn8pLZuYvTovLuqvtKmAsC8TbXY5g=; h=Date:From:To:Cc:Subject:In-Reply-To:References:From; b=nzjVoyEg0Sbhq0M0WQNRpfqqxHb8+ABjG+E9JKZLvuvHNJIEYrWOU9QRShN98AI14 JtSVHwAHICLE+VdvCn2Nl5LPIQJGSZkmHs6HuFDJVfG+ksNYK0uWFjCm8J18L8ZRC1 Vw776a70RVUdHW+h37RJWSia8Vullf7XPu29PCXc= MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII; format=flowed Content-Transfer-Encoding: 7bit Date: Fri, 04 Jan 2019 10:35:58 +0530 From: Arun KS To: Michal Hocko Cc: arunks.linux@gmail.com, akpm@linux-foundation.org, vbabka@suse.cz, osalvador@suse.de, linux-kernel@vger.kernel.org, linux-mm@kvack.org, getarunks@gmail.com Subject: Re: [PATCH v6 1/2] memory_hotplug: Free pages as higher order In-Reply-To: <5e55c6e64a2bfd6eed855ea17a34788b@codeaurora.org> References: <1541484194-1493-1-git-send-email-arunks@codeaurora.org> <20181106140638.GN27423@dhcp22.suse.cz> <542cd3516b54d88d1bffede02c6045b8@codeaurora.org> <20181106200823.GT27423@dhcp22.suse.cz> <5e55c6e64a2bfd6eed855ea17a34788b@codeaurora.org> Message-ID: <40a4d5154fbd0006fbe55eb68703bb65@codeaurora.org> X-Sender: arunks@codeaurora.org User-Agent: Roundcube Webmail/1.2.5 Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 2018-11-07 11:51, Arun KS wrote: > On 2018-11-07 01:38, Michal Hocko wrote: >> On Tue 06-11-18 21:01:29, Arun KS wrote: >>> On 2018-11-06 19:36, Michal Hocko wrote: >>> > On Tue 06-11-18 11:33:13, Arun KS wrote: >>> > > When free pages are done with higher order, time spend on >>> > > coalescing pages by buddy allocator can be reduced. With >>> > > section size of 256MB, hot add latency of a single section >>> > > shows improvement from 50-60 ms to less than 1 ms, hence >>> > > improving the hot add latency by 60%. Modify external >>> > > providers of online callback to align with the change. >>> > > >>> > > This patch modifies totalram_pages, zone->managed_pages and >>> > > totalhigh_pages outside managed_page_count_lock. A follow up >>> > > series will be send to convert these variable to atomic to >>> > > avoid readers potentially seeing a store tear. >>> > >>> > Is there any reason to rush this through rather than wait for counters >>> > conversion first? >>> >>> Sure Michal. >>> >>> Conversion patch, https://patchwork.kernel.org/cover/10657217/ is >>> currently >>> incremental to this patch. >> >> The ordering should be other way around. Because as things stand with >> this patch first it is possible to introduce a subtle race prone >> updates. As I've said I am skeptical the race would matter, really, >> but >> there is no real reason to risk for that. Especially when you have the >> other (first) half ready. > > Makes sense. I have rebased the preparatory patch on top of -rc1. > https://patchwork.kernel.org/patch/10670787/ Hello Michal, Please review version 7 sent, https://lore.kernel.org/patchwork/patch/1028908/ Regards, Arun > > Regards, > Arun