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=-2.2 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,USER_AGENT_SANE_1 autolearn=no 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 1FE25C432C3 for ; Tue, 3 Dec 2019 22:14:39 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id F00062073C for ; Tue, 3 Dec 2019 22:14:38 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727781AbfLCWOe (ORCPT ); Tue, 3 Dec 2019 17:14:34 -0500 Received: from mga01.intel.com ([192.55.52.88]:19309 "EHLO mga01.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727502AbfLCWOe (ORCPT ); Tue, 3 Dec 2019 17:14:34 -0500 X-Amp-Result: UNKNOWN X-Amp-Original-Verdict: FILE UNKNOWN X-Amp-File-Uploaded: False Received: from orsmga007.jf.intel.com ([10.7.209.58]) by fmsmga101.fm.intel.com with ESMTP/TLS/DHE-RSA-AES256-GCM-SHA384; 03 Dec 2019 14:14:33 -0800 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.69,275,1571727600"; d="scan'208";a="201159390" Received: from sjchrist-coffee.jf.intel.com (HELO linux.intel.com) ([10.54.74.41]) by orsmga007.jf.intel.com with ESMTP; 03 Dec 2019 14:14:33 -0800 Date: Tue, 3 Dec 2019 14:14:33 -0800 From: Sean Christopherson To: James Hogan , Paul Mackerras , Christian Borntraeger , Janosch Frank , Paolo Bonzini , Radim =?utf-8?B?S3LEjW3DocWZ?= , Marc Zyngier Cc: David Hildenbrand , Cornelia Huck , Vitaly Kuznetsov , Wanpeng Li , Jim Mattson , Joerg Roedel , James Morse , Julien Thierry , Suzuki K Poulose , linux-mips@vger.kernel.org, kvm-ppc@vger.kernel.org, kvm@vger.kernel.org, linux-arm-kernel@lists.infradead.org, kvmarm@lists.cs.columbia.edu, linux-kernel@vger.kernel.org, Christoffer Dall Subject: Re: [PATCH v3 00/15] KVM: Dynamically size memslot arrays Message-ID: <20191203221433.GK19877@linux.intel.com> References: <20191024230744.14543-1-sean.j.christopherson@intel.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20191024230744.14543-1-sean.j.christopherson@intel.com> User-Agent: Mutt/1.5.24 (2015-08-30) Sender: linux-mips-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-mips@vger.kernel.org On Thu, Oct 24, 2019 at 04:07:29PM -0700, Sean Christopherson wrote: > The end goal of this series is to dynamically size the memslot array so > that KVM allocates memory based on the number of memslots in use, as > opposed to unconditionally allocating memory for the maximum number of > memslots. On x86, each memslot consumes 88 bytes, and so with 2 address > spaces of 512 memslots, each VM consumes ~90k bytes for the memslots. > E.g. given a VM that uses a total of 30 memslots, dynamic sizing reduces > the memory footprint from 90k to ~2.6k bytes. > > The changes required to support dynamic sizing are relatively small, > e.g. are essentially contained in patches 14/15 and 15/15. Patches 1-13 > clean up the memslot code, which has gotten quite crusty, especially > __kvm_set_memory_region(). The clean up is likely not strictly necessary > to switch to dynamic sizing, but I didn't have a remotely reasonable > level of confidence in the correctness of the dynamic sizing without first > doing the clean up. > > Christoffer, I added your Tested-by to the patches that I was confident > would be fully tested based on the desription of what you tested. Let me > know if you disagree with any of 'em. > > v3: > - Fix build errors on PPC and MIPS due to missed params during > refactoring [kbuild test robot]. > - Rename the helpers for update_memslots() and add comments describing > the new algorithm and how it interacts with searching [Paolo]. > - Remove the unnecessary and obnoxious warning regarding memslots being > a flexible array [Paolo]. > - Fix typos in the changelog of patch 09/15 [Christoffer]. > - Collect tags [Christoffer]. > > v2: > - Split "Drop kvm_arch_create_memslot()" into three patches to move > minor functional changes to standalone patches [Janosch]. > - Rebase to latest kvm/queue (f0574a1cea5b, "KVM: x86: fix ...") > - Collect an Acked-by and a Reviewed-by Paolo, do you want me to rebase this to the latest kvm/queue?