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=-8.5 required=3.0 tests=BAYES_00,DKIM_INVALID, DKIM_SIGNED,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED 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 828D2C3E8C5 for ; Fri, 27 Nov 2020 17:08:22 +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 1A33D208CA for ; Fri, 27 Nov 2020 17:08:21 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b="g5jVeC55" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 1A33D208CA Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=redhat.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Received: from localhost ([::1]:57728 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1kihEK-0001io-R8 for qemu-devel@archiver.kernel.org; Fri, 27 Nov 2020 12:08:20 -0500 Received: from eggs.gnu.org ([2001:470:142:3::10]:44942) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1kihCu-0000st-HH for qemu-devel@nongnu.org; Fri, 27 Nov 2020 12:06:53 -0500 Received: from us-smtp-delivery-124.mimecast.com ([216.205.24.124]:38384) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_CBC_SHA1:256) (Exim 4.90_1) (envelope-from ) id 1kihCq-0000BB-LH for qemu-devel@nongnu.org; Fri, 27 Nov 2020 12:06:52 -0500 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1606496806; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: in-reply-to:in-reply-to:references:references; bh=VsMD/TNi6ukZFU8H+l4UaQHr6+mx6Ik2lRYX2H9mdYc=; b=g5jVeC55utfSZwJC7McKYSEvaJRKFjizt7p0fk1wGL9hGQ61A8EWVKDbH1/3DQIN/00W0K eoh1e4KsCKdVY7egChJwom7Z71vWzJpBtI4uVW2D3t2OnbDUP91e5jITP6txXca/rOpTg0 jk/U82ubPPGgmri+rrpiYlGVCB/5GkA= Received: from mimecast-mx01.redhat.com (mimecast-mx01.redhat.com [209.132.183.4]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-255-jPpvFywZMzWjcGOiEJiYzQ-1; Fri, 27 Nov 2020 12:06:42 -0500 X-MC-Unique: jPpvFywZMzWjcGOiEJiYzQ-1 Received: from smtp.corp.redhat.com (int-mx06.intmail.prod.int.phx2.redhat.com [10.5.11.16]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id 0A51D107ACF7; Fri, 27 Nov 2020 17:06:40 +0000 (UTC) Received: from localhost (unknown [10.10.67.2]) by smtp.corp.redhat.com (Postfix) with ESMTP id 56B785C1C2; Fri, 27 Nov 2020 17:06:36 +0000 (UTC) Date: Fri, 27 Nov 2020 12:06:34 -0500 From: Eduardo Habkost To: Claudio Fontana Subject: Re: [RFC v6 10/11] accel: introduce AccelCPUClass extending CPUClass Message-ID: <20201127170634.GA2271382@habkost.net> References: <20201126223218.31480-1-cfontana@suse.de> <20201126223218.31480-11-cfontana@suse.de> MIME-Version: 1.0 In-Reply-To: <20201126223218.31480-11-cfontana@suse.de> X-Scanned-By: MIMEDefang 2.79 on 10.5.11.16 Authentication-Results: relay.mimecast.com; auth=pass smtp.auth=CUSA124A263 smtp.mailfrom=ehabkost@redhat.com X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: redhat.com Content-Type: text/plain; charset=utf-8 Content-Disposition: inline Received-SPF: pass client-ip=216.205.24.124; envelope-from=ehabkost@redhat.com; helo=us-smtp-delivery-124.mimecast.com X-Spam_score_int: -20 X-Spam_score: -2.1 X-Spam_bar: -- X-Spam_report: (-2.1 / 5.0 requ) BAYES_00=-1.9, DKIMWL_WL_HIGH=-0.001, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, RCVD_IN_DNSWL_NONE=-0.0001, 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: Paul Durrant , Jason Wang , qemu-devel@nongnu.org, Peter Xu , haxm-team@intel.com, Colin Xu , Olaf Hering , Stefano Stabellini , Bruce Rogers , "Emilio G . Cota" , Anthony Perard , Philippe =?utf-8?Q?Mathieu-Daud=C3=A9?= , Laurent Vivier , Thomas Huth , Richard Henderson , Cameron Esfahani , Dario Faggioli , Roman Bolshakov , Sunil Muthuswamy , Marcelo Tosatti , Wenchao Wang , Paolo Bonzini Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: "Qemu-devel" On Thu, Nov 26, 2020 at 11:32:17PM +0100, Claudio Fontana wrote: > add a new optional interface to CPUClass, > which allows accelerators to extend the CPUClass > with additional accelerator-specific initializations. > > Signed-off-by: Claudio Fontana > --- [...] > +static void accel_init_cpu_int_aux(ObjectClass *klass, void *opaque) > +{ > + CPUClass *cc = CPU_CLASS(klass); > + AccelCPUClass *accel_cpu_interface = opaque; > + > + cc->accel_cpu_interface = accel_cpu_interface; > + if (accel_cpu_interface->cpu_class_init) { > + accel_cpu_interface->cpu_class_init(cc); > + } > +} So, now that the approach we're following to trigger the accel_init_cpu*() call is less controversial (thanks for your patience!), we can try to address the monkey patching issue: Monkey patching classes like this is acceptable as an initial solution, but I'd like us to have a plan to eventually get rid of it. Monkey patching CPU classes makes querying of CPU model information less predictable and subtly dependent on QEMU initialization state. Removing CPUClass.accel_cpu_interface may be easy, because it should be possible to just call current_accel() when realizing CPUs. Getting rid of CPUClass.cpu_class_init might be more difficult, depending on what the ->cpu_class_init() function is doing. > + > +/* initialize the arch-specific accel CpuClass interfaces */ > +static void accel_init_cpu_interfaces(AccelClass *ac, const char *cpu_type) > +{ > + const char *ac_name; /* AccelClass name */ > + char *acc_name; /* AccelCPUClass name */ > + ObjectClass *acc; /* AccelCPUClass */ > + > + ac_name = object_class_get_name(OBJECT_CLASS(ac)); > + g_assert(ac_name != NULL); > + > + acc_name = g_strdup_printf("%s-%s", ac_name, CPU_RESOLVING_TYPE); > + acc = object_class_by_name(acc_name); > + g_free(acc_name); > + > + if (acc) { > + object_class_foreach(accel_init_cpu_int_aux, cpu_type, false, acc); > + } > +} > + > void accel_init_interfaces(AccelClass *ac, const char *cpu_type) > { > #ifndef CONFIG_USER_ONLY > accel_init_ops_interfaces(ac); > #endif /* !CONFIG_USER_ONLY */ > + > + accel_init_cpu_interfaces(ac, cpu_type); > } [...] -- Eduardo