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=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 6DDC1C5CFE7 for ; Wed, 11 Jul 2018 10:48:41 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 2239720846 for ; Wed, 11 Jul 2018 10:48:41 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 2239720846 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=intel.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1732451AbeGKKwV (ORCPT ); Wed, 11 Jul 2018 06:52:21 -0400 Received: from mga02.intel.com ([134.134.136.20]:31165 "EHLO mga02.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726487AbeGKKwV (ORCPT ); Wed, 11 Jul 2018 06:52:21 -0400 X-Amp-Result: SKIPPED(no attachment in message) X-Amp-File-Uploaded: False Received: from orsmga005.jf.intel.com ([10.7.209.41]) by orsmga101.jf.intel.com with ESMTP/TLS/DHE-RSA-AES256-GCM-SHA384; 11 Jul 2018 03:48:38 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.51,338,1526367600"; d="scan'208";a="239478214" Received: from unknown (HELO [10.239.13.97]) ([10.239.13.97]) by orsmga005.jf.intel.com with ESMTP; 11 Jul 2018 03:48:35 -0700 Message-ID: <5B45E17D.2090205@intel.com> Date: Wed, 11 Jul 2018 18:52:45 +0800 From: Wei Wang User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:31.0) Gecko/20100101 Thunderbird/31.7.0 MIME-Version: 1.0 To: Michal Hocko , Linus Torvalds CC: virtio-dev@lists.oasis-open.org, Linux Kernel Mailing List , virtualization , KVM list , linux-mm , "Michael S. Tsirkin" , Andrew Morton , Paolo Bonzini , liliang.opensource@gmail.com, yang.zhang.wz@gmail.com, quan.xu0@gmail.com, nilal@redhat.com, Rik van Riel , peterx@redhat.com Subject: Re: [PATCH v35 1/5] mm: support to get hints of free page blocks References: <1531215067-35472-1-git-send-email-wei.w.wang@intel.com> <1531215067-35472-2-git-send-email-wei.w.wang@intel.com> <5B455D50.90902@intel.com> <20180711092152.GE20050@dhcp22.suse.cz> In-Reply-To: <20180711092152.GE20050@dhcp22.suse.cz> Content-Type: text/plain; charset=windows-1252; format=flowed Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 07/11/2018 05:21 PM, Michal Hocko wrote: > On Tue 10-07-18 18:44:34, Linus Torvalds wrote: > [...] >> That was what I tried to encourage with actually removing the pages >> form the page list. That would be an _incremental_ interface. You can >> remove MAX_ORDER-1 pages one by one (or a hundred at a time), and mark >> them free for ballooning that way. And if you still feel you have tons >> of free memory, just continue removing more pages from the free list. > We already have an interface for that. alloc_pages(GFP_NOWAIT, MAX_ORDER -1). > So why do we need any array based interface? Yes, I'm trying to get free pages directly via alloc_pages, so there will be no new mm APIs. I plan to let free page allocation stop when the remaining system free memory becomes close to min_free_kbytes (prevent swapping). Best, Wei