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 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 smtp.lore.kernel.org (Postfix) with ESMTPS id A0D06C36010 for ; Mon, 7 Apr 2025 12:34:23 +0000 (UTC) Received: from localhost ([::1] helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1u1lfO-0001gs-34; Mon, 07 Apr 2025 08:33:31 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1u1lfM-0001gS-0B for qemu-devel@nongnu.org; Mon, 07 Apr 2025 08:33:28 -0400 Received: from us-smtp-delivery-124.mimecast.com ([170.10.129.124]) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1u1lfH-0000zM-Ve for qemu-devel@nongnu.org; Mon, 07 Apr 2025 08:33:27 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1744029201; 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=bC8nBTne87FShfgPevYSEiNOFCAwW0SvjNSi9478owE=; b=i80iyTCH53TxkOMEyzB1YNjp0TO69PphoMxrFgazHPJvAlA3Xg92qor+aba1g4CxF+WZX9 DZOiQbmg5I4P+odnDZurrp3/dPhXps6kJJ/cwVaty9LG+dDH4CshE5HcAw0dL9fwUT7D8h TkpgxXJ3Ik+iQaL+5xktxy6lNGAlHWQ= Received: from mx-prod-mc-06.mail-002.prod.us-west-2.aws.redhat.com (ec2-35-165-154-97.us-west-2.compute.amazonaws.com [35.165.154.97]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.3, cipher=TLS_AES_256_GCM_SHA384) id us-mta-59-N_NoGigyOJq1DCVz808ciA-1; Mon, 07 Apr 2025 08:33:17 -0400 X-MC-Unique: N_NoGigyOJq1DCVz808ciA-1 X-Mimecast-MFC-AGG-ID: N_NoGigyOJq1DCVz808ciA_1744029196 Received: from mx-prod-int-06.mail-002.prod.us-west-2.aws.redhat.com (mx-prod-int-06.mail-002.prod.us-west-2.aws.redhat.com [10.30.177.93]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits) server-digest SHA256) (No client certificate requested) by mx-prod-mc-06.mail-002.prod.us-west-2.aws.redhat.com (Postfix) with ESMTPS id 00F101800259; Mon, 7 Apr 2025 12:33:15 +0000 (UTC) Received: from blackfin.pond.sub.org (unknown [10.44.22.7]) by mx-prod-int-06.mail-002.prod.us-west-2.aws.redhat.com (Postfix) with ESMTPS id 5C00B1828AA4; Mon, 7 Apr 2025 12:33:12 +0000 (UTC) Received: by blackfin.pond.sub.org (Postfix, from userid 1000) id 7343421E66C5; Mon, 07 Apr 2025 14:33:10 +0200 (CEST) From: Markus Armbruster To: Mario Fleischmann Cc: qemu-devel@nongnu.org, alex.bennee@linaro.org, philmd@linaro.org, christian.boenig@lauterbach.com Subject: Re: [PATCH 00/16] Add Multi-Core Debug (MCD) API support In-Reply-To: <20250310150510.200607-1-mario.fleischmann@lauterbach.com> (Mario Fleischmann's message of "Mon, 10 Mar 2025 16:04:54 +0100") References: <20250310150510.200607-1-mario.fleischmann@lauterbach.com> Date: Mon, 07 Apr 2025 14:33:10 +0200 Message-ID: <87semkw3qx.fsf@pond.sub.org> User-Agent: Gnus/5.13 (Gnus v5.13) MIME-Version: 1.0 Content-Type: text/plain X-Scanned-By: MIMEDefang 3.4.1 on 10.30.177.93 Received-SPF: pass client-ip=170.10.129.124; envelope-from=armbru@redhat.com; helo=us-smtp-delivery-124.mimecast.com X-Spam_score_int: -23 X-Spam_score: -2.4 X-Spam_bar: -- X-Spam_report: (-2.4 / 5.0 requ) BAYES_00=-1.9, DKIMWL_WL_HIGH=-0.32, 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_H2=0.001, RCVD_IN_VALIDITY_CERTIFIED_BLOCKED=0.001, RCVD_IN_VALIDITY_RPBL_BLOCKED=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: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Mario Fleischmann writes: > This patch series introduces support for the Multi-Core Debug (MCD) API, a > commonly used debug interface by emulators. The MCD API, defined through a > header file, consists of 54 functions for implementing debug and trace. > However, since it is a header-file-only interface, MCD does not specify a > communication protocol. We get around this limitation by following a remote > procedure call approach using QMP. The client stub corresponding to this > implementation can be found at https://gitlab.com/lauterbach/mcdrefsrv > > This series is the successor to: > "[PATCH v5 00/18] first version of mcdstub" > (https://patchew.org/QEMU/20231220162555.19545-1-nicolas.eder@lauterbach.com/) > > * Architecture-independent MCD implementation > * QMP instead of custom TCP protocol Rationale? There must be pros and cons. How much data would you expect to flow in practical usage? QMP isn't designed for bulk transfer... > qemu-system- [options] -qmp tcp::1235,server=on,wait=off > > * Architecture-independent QTest test suite > > V=1 QTEST_QEMU_BINARY="./qemu-system- [options]" tests/qtest/mcd-test > > * Architecture-specific tests can be found at the client stub [...] > qapi/mcd.json | 2366 ++++++++++++++++++++++ This is *massive*. By non-blank, non-comment lines, it's the second largest module in qapi/, almost 9% of the entire schema. It's larger than the entire QEMU guest agent QAPI schema. The QAPI generator generates some 280KiB of C code for it. [...]