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 B6FEEC48BEB for ; Thu, 15 Feb 2024 10:38:30 +0000 (UTC) Received: from localhost ([::1] helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1raZ8A-0006jW-Of; Thu, 15 Feb 2024 05:38:14 -0500 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 1raZ88-0006iV-FX for qemu-devel@nongnu.org; Thu, 15 Feb 2024 05:38:12 -0500 Received: from mail-ed1-x52c.google.com ([2a00:1450:4864:20::52c]) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_128_GCM_SHA256:128) (Exim 4.90_1) (envelope-from ) id 1raZ86-0004MU-OI for qemu-devel@nongnu.org; Thu, 15 Feb 2024 05:38:11 -0500 Received: by mail-ed1-x52c.google.com with SMTP id 4fb4d7f45d1cf-55f0b2c79cdso1109694a12.3 for ; Thu, 15 Feb 2024 02:38:10 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linaro.org; s=google; t=1707993489; x=1708598289; darn=nongnu.org; h=content-transfer-encoding:cc:to:subject:message-id:date:from :in-reply-to:references:mime-version:from:to:cc:subject:date :message-id:reply-to; bh=uAgLWWhpsYnuKcbs+qV32uEp/+I9i315cGj5ltW31Zc=; b=ySFL6RI6QnncEGvfkC/IQmSsvdsSGZm+5aqq++TNl6Niq/gwmXUZhBt5IRShCGMVOJ f97cDZwNZJ7PBDXcDTB7w6a1JdoZo42Xk6PdnF8TJVhpKJGmb0xmEG++Wq3IZzFlpeGU A6GSyi+TY8N4GMgyYZ0nTk5iV0+/WIb0atpo6XKp/gaOIpxdCAF0tdK76AZM2ziePc5e 4r7OWyLPXlMzzWMfhgaYKYe8dUpEBIcwXAekeE25Ds8UPw5JHqITZnv8RHAQXiu9ipAN vA1ntCoR6Sj3EXMq+XzFaC0X8Dn6+Z0f2cl6QMmZ0SEJ8ykcdGLDQEtz3HeMYE9JkbdU KKyg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1707993489; x=1708598289; h=content-transfer-encoding:cc:to:subject:message-id:date:from :in-reply-to:references:mime-version:x-gm-message-state:from:to:cc :subject:date:message-id:reply-to; bh=uAgLWWhpsYnuKcbs+qV32uEp/+I9i315cGj5ltW31Zc=; b=IvDGdvAD2BbvPyCfzqc1Fad98CGsRHg2YWkTm6M+VpJDgWVIQNVfrJW9Yu+AA3dya8 weN+uhKf7itHWLavpIvWnnePT6lFbIMv7RLoHDLbTAJGgLx84CUdISRh297OHIL2rles jk+4uinBVCpU15h3nrwtcv2xdLpCRNpPTE/UFVLYcjUlcM/JSSM+fuqSZy0BByETGYBy h36n2HKwj0GsQA7qHQIEfLqLyIPxgz8loXNseGcrriNNCrrzLz5+x2kK2GeP0Q4MytDf KDgsGd1cpNJskdDRJhMDQ3vzMrVautFxaq++Wh9T9P7d7omyFasFBlDryvqlcADBsDd0 UP/A== X-Gm-Message-State: AOJu0Yxgg/ptFrk/XVKhogyAE+MuyABPa5LzYu3E9TtgP5g8HJyXSwTJ hI5rMOR69Akf08X/VeHC9VtopFvZbRuOvHbaTCzJ2t/l1Wf1I2Ai+cXLAlwDixGbPwEHOn52/gj 5jATILYNtQj5fmndylSKBjxBR5RdQnaOwBb3mKzrY3DSxm6EL X-Google-Smtp-Source: AGHT+IGuZLN3ynu/eR2qMLnqgbf8EBBm3Q3I5G9nBLIVKxfwwelYQEu/d4dSUbkQ1Wb6KpPsJXQnHJxJrUBVYFUaGyM= X-Received: by 2002:a05:6402:148d:b0:561:dd88:efde with SMTP id e13-20020a056402148d00b00561dd88efdemr1079519edv.27.1707993489235; Thu, 15 Feb 2024 02:38:09 -0800 (PST) MIME-Version: 1.0 References: In-Reply-To: From: Peter Maydell Date: Thu, 15 Feb 2024 10:37:57 +0000 Message-ID: Subject: Re: Assessment of the difficulty in porting CPU architecture for qemu To: =?UTF-8?B?5pa5?= <1584389042@qq.com> Cc: qemu-devel Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable Received-SPF: pass client-ip=2a00:1450:4864:20::52c; envelope-from=peter.maydell@linaro.org; helo=mail-ed1-x52c.google.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, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, RCVD_IN_DNSWL_NONE=-0.0001, SPF_HELO_NONE=0.001, SPF_PASS=-0.001, T_SCC_BODY_TEXT_LINE=-0.01 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 On Fri, 17 Nov 2023 at 07:35, =E6=96=B9 <1584389042@qq.com> wrote: > > Hello everyone! I am working on implementing a tool to assess the comple= xity of CPU architecture porting. It primarily focuses on RISC-V architectu= re porting. In fact, the tool may have an average estimate of various archi= tecture porting efforts.My focus is on the overall workload and difficulty = of transplantation in the past and future,even if a project has already bee= n ported.As part of my dataset, I have collected the **qemu** project. **I = would like to gather community opinions to support my assessment. I appreci= ate your help and response!** Based on scanning tools, the porting complexi= ty is determined to be high, with a significant amount of code related to t= he CPU architecture in the project. You should be careful here to distinguish the code in QEMU which is related to handling RISC-V as a *guest* architecture (i.e. one which QEMU emulates) from the code which is related to handling RISC-V as a *host* architecture. For purposes of "porting QEMU to a RISC-V host", only the latter complexity counts. The former we would have to do anyway, even if QEMU only ever ran on x86-64 machines. You should check whether your scanner has correctly figured this out. -- PMM