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 vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 611BFECAAA2 for ; Mon, 29 Aug 2022 03:52:45 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229527AbiH2Dwn (ORCPT ); Sun, 28 Aug 2022 23:52:43 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:58002 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229457AbiH2Dwl (ORCPT ); Sun, 28 Aug 2022 23:52:41 -0400 Received: from mail-pf1-x429.google.com (mail-pf1-x429.google.com [IPv6:2607:f8b0:4864:20::429]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 14E37402CE for ; Sun, 28 Aug 2022 20:52:41 -0700 (PDT) Received: by mail-pf1-x429.google.com with SMTP id z187so6970003pfb.12 for ; Sun, 28 Aug 2022 20:52:41 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20210112; h=user-agent:in-reply-to:content-disposition:mime-version:references :message-id:subject:cc:to:from:date:from:to:cc; bh=hC9a6VjiRDFmPP4lAwhT38/UuH6AeBV07jfmc/Byr20=; b=Dd12flyZ+5uXKdEJoxw0VkPK1uNnHuxvoffdJHrKvPxeYnspkg75e7F0B/W48pdnkn M6u5tT80aQqUJKRRDkisT31khpytUScXyW9iZPXOoEdvC13sUT5D9iw/+ractzd9cX8e xensOxDk/HntRpCtByRQjJqG4rJMhSZQEsfTDw/lKZUM+r6Ufl0D6cPcjIVfFEt0pzdr ko37cukAmzALSinOHt9+XuqFZ5pBlPwrPCsUfIutBym0ToX5nssHufeIEuRt97MBULqN omt7zk5ZylzyfKV0GXcvxaeGm8W10awf5raf+aj3KMg89Cop4aR3vDf0hZjK7XQ7z0z9 vTdQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=user-agent:in-reply-to:content-disposition:mime-version:references :message-id:subject:cc:to:from:date:x-gm-message-state:from:to:cc; bh=hC9a6VjiRDFmPP4lAwhT38/UuH6AeBV07jfmc/Byr20=; b=EuEPD9lirSZH2ZW/+Aa0bPI9UYQRITjQ2ORJnc8G+9l2vTESy+7Q4kqbCOyEickrNy PrlV/H4qrOSjz69E/uGBwPwAm9Ogk5UFfvsrbL9CutiJpzSSpVslOzRhS3rUr65HBZRZ 6tiSO5c31+52xHpd3S0Vm/UozYPsoV+eUXhoPLR/fIt1gmCP5AAUkQcT68GImPj2Ll8q 3AHK42ub9Pp8c5K+INskMPLaYcWjpG/KEA6qc9TJqoruTUONhloreGmYvgiGCD+XkYrX xPzS77bRYq2wmYOkUWm0Wvuc5GLZIwTN72X+NC6hF0oqhZt9m6FWggIFu30HI3SRu3kt 0aTw== X-Gm-Message-State: ACgBeo033b1Kcc+lXwBgFDIF717ct+bt4le/O9wFA6YqU1eunFPxwAVU qGDI7ENfUgT5/D6NT5El+cQqqscL40dcZg== X-Google-Smtp-Source: AA6agR5SCzC3RHmi6oq0B9IeD1j2PdMx96DkGBY95dwliMrogkMMF1CSI7VbfqXOs8qBIyRLTMAmJg== X-Received: by 2002:a05:6a00:8cc:b0:52c:7ab5:2ce7 with SMTP id s12-20020a056a0008cc00b0052c7ab52ce7mr14497792pfu.28.1661745160541; Sun, 28 Aug 2022 20:52:40 -0700 (PDT) Received: from dell-PowerEdge-T440 ([183.14.135.208]) by smtp.gmail.com with ESMTPSA id s16-20020a17090a075000b001faa4a6691asm5443857pje.30.2022.08.28.20.52.38 (version=TLS1_2 cipher=ECDHE-RSA-CHACHA20-POLY1305 bits=256/256); Sun, 28 Aug 2022 20:52:39 -0700 (PDT) Date: Mon, 29 Aug 2022 11:52:33 +0800 From: Puyou Lu To: Marc Zyngier Cc: Thomas Gleixner , Robert Richter , Catalin Marinas , linux-kernel@vger.kernel.org Subject: Re: [PATCH] irqchip/gic-v3: do runtime cpu cap check only when necessary Message-ID: <20220829035232.GA13376@dell-PowerEdge-T440> References: <20220827051328.GA18042@lu-N56VJ> <87wnatra83.wl-maz@kernel.org> <20220828075610.GA30202@lu-N56VJ> <87r110qong.wl-maz@kernel.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <87r110qong.wl-maz@kernel.org> User-Agent: Mutt/1.9.4 (2018-02-28) Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Sun, Aug 28, 2022 at 06:11:15PM +0100, Marc Zyngier wrote: > Well, what you got wrong is that these instructions are stepped over > two branches when the caps are finalised, and that doesn't appear in > the disassembly (you need to look at the code that is actually > executed). > > Now, any optimisation of the sort must be backed by some performance > numbers. If you can show that this has a meaningful impact on a given > workload, I'm happy to look into it. But only if you can show that > data. > > Thanks, > > M. > > -- > Without deviation from the norm, progress is not possible. Thank you very much for correcting me, and sorry for wasting your time, I got it now.