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=-10.3 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI,NICE_REPLY_A, SPF_HELO_NONE,SPF_PASS,USER_AGENT_SANE_1 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 F2F25C433B4 for ; Thu, 8 Apr 2021 14:29:25 +0000 (UTC) Received: from lists.gnu.org (lists.gnu.org [209.51.188.17]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 59E9A610CC for ; Thu, 8 Apr 2021 14:29:25 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 59E9A610CC Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=suse.de Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Received: from localhost ([::1]:53682 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1lUVeu-0006ry-Hc for qemu-devel@archiver.kernel.org; Thu, 08 Apr 2021 10:29:24 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]:45282) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1lUVdw-0006RU-4W for qemu-devel@nongnu.org; Thu, 08 Apr 2021 10:28:29 -0400 Received: from mx2.suse.de ([195.135.220.15]:51436) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1lUVdt-0003OF-UU for qemu-devel@nongnu.org; Thu, 08 Apr 2021 10:28:23 -0400 X-Virus-Scanned: by amavisd-new at test-mx.suse.de Received: from relay2.suse.de (unknown [195.135.221.27]) by mx2.suse.de (Postfix) with ESMTP id 63620B032; Thu, 8 Apr 2021 14:28:19 +0000 (UTC) Subject: Re: [RFC v12 51/65] target/arm: cpu-sve: split TCG and KVM functionality To: Richard Henderson , Peter Maydell , =?UTF-8?Q?Philippe_Mathieu-Daud=c3=a9?= , =?UTF-8?Q?Alex_Benn=c3=a9e?= References: <20210326193701.5981-1-cfontana@suse.de> <20210326193701.5981-52-cfontana@suse.de> <573a18c3-dc67-12f9-9cdb-826cf3c9ec00@linaro.org> From: Claudio Fontana Message-ID: Date: Thu, 8 Apr 2021 16:28:18 +0200 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:68.0) Gecko/20100101 Thunderbird/68.12.0 MIME-Version: 1.0 In-Reply-To: <573a18c3-dc67-12f9-9cdb-826cf3c9ec00@linaro.org> Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 7bit Received-SPF: pass client-ip=195.135.220.15; envelope-from=cfontana@suse.de; helo=mx2.suse.de X-Spam_score_int: -41 X-Spam_score: -4.2 X-Spam_bar: ---- X-Spam_report: (-4.2 / 5.0 requ) BAYES_00=-1.9, NICE_REPLY_A=-0.001, RCVD_IN_DNSWL_MED=-2.3, RCVD_IN_MSPIKE_H3=0.001, RCVD_IN_MSPIKE_WL=0.001, SPF_HELO_NONE=0.001, SPF_PASS=-0.001 autolearn=ham autolearn_force=no X-Spam_action: no action X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.23 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Paolo Bonzini , Roman Bolshakov , qemu-devel@nongnu.org, Eduardo Habkost Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: "Qemu-devel" On 3/28/21 8:21 PM, Richard Henderson wrote: > On 3/26/21 1:36 PM, Claudio Fontana wrote: >> +++ b/target/arm/kvm/kvm-sve.h >> @@ -0,0 +1,30 @@ >> +/* >> + * QEMU AArch64 CPU SVE KVM interface >> + * >> + * Copyright 2021 SUSE LLC >> + * >> + * This work is licensed under the terms of the GNU GPL, version 2 or later. >> + * See the COPYING file in the top-level directory. >> + */ >> + >> +#ifndef KVM_SVE_H >> +#define KVM_SVE_H >> + >> +/* note: SVE is an AARCH64-only option, only include this for TARGET_AARCH64 */ > > A pointless comment given that kvm itself is aarch64-only. > >> -void cpu_sve_finalize_features(ARMCPU *cpu, Error **errp) >> +bool cpu_sve_finalize_features(ARMCPU *cpu, Error **errp) > > The commit message does not mention the interface change here. Ok, would need the two-steps here too. > > I'm not sure about the rest of this patch. It saves a miniscule amount of code > in a kvm-only build, but I don't know that it clarifies things at all. I would say that it does, if only by making the code flow easier to follow. > > As yet, the other arm hw accelerators do not support SVE, but I assume that's > only a matter of time. The ARM Neoverse cpus support SVE, and will require Xen > to have an answer soon. (Apple will do whatever Apple does, given that it fabs > its own ARM cpus, but I expect they won't delay SVE forever.) > > It's not clear to me what bits of the kvm code here is really kvm specific, or > if we'll have to move it back. > > I'm tempted to leave it alone for now. But fair enough, if nobody speaks up and finds them useful other than me, I would drop this from the series. > > > r~ >