Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753658AbdFMR7L (ORCPT ); Tue, 13 Jun 2017 13:59:11 -0400 Received: from mga11.intel.com ([192.55.52.93]:52745 "EHLO mga11.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752489AbdFMR7K (ORCPT ); Tue, 13 Jun 2017 13:59:10 -0400 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.39,338,1493708400"; d="scan'208";a="97582202" Subject: Re: [PATCH v11 3/6] virtio-balloon: VIRTIO_BALLOON_F_PAGE_CHUNKS To: "Michael S. Tsirkin" , Wei Wang References: <1497004901-30593-1-git-send-email-wei.w.wang@intel.com> <1497004901-30593-4-git-send-email-wei.w.wang@intel.com> <20170613200049-mutt-send-email-mst@kernel.org> Cc: virtio-dev@lists.oasis-open.org, linux-kernel@vger.kernel.org, qemu-devel@nongnu.org, virtualization@lists.linux-foundation.org, kvm@vger.kernel.org, linux-mm@kvack.org, david@redhat.com, cornelia.huck@de.ibm.com, akpm@linux-foundation.org, mgorman@techsingularity.net, aarcange@redhat.com, amit.shah@redhat.com, pbonzini@redhat.com, liliang.opensource@gmail.com, Matthew Wilcox From: Dave Hansen Message-ID: Date: Tue, 13 Jun 2017 10:59:07 -0700 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:52.0) Gecko/20100101 Thunderbird/52.1.1 MIME-Version: 1.0 In-Reply-To: <20170613200049-mutt-send-email-mst@kernel.org> Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 369 Lines: 10 On 06/13/2017 10:56 AM, Michael S. Tsirkin wrote: >> +/* The size of one page_bmap used to record inflated/deflated pages. */ >> +#define VIRTIO_BALLOON_PAGE_BMAP_SIZE (8 * PAGE_SIZE) > At this size, you probably want alloc_pages to avoid kmalloc > overhead. For slub, at least, kmalloc() just calls alloc_pages() basically directly. There's virtually no overhead.