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=-2.1 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, USER_AGENT_SANE_1 autolearn=no 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 646F0C433E1 for ; Wed, 13 May 2020 18:43:02 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 13993205ED for ; Wed, 13 May 2020 18:43:03 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="EhETGKly" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2390203AbgEMSnB (ORCPT ); Wed, 13 May 2020 14:43:01 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:47792 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-FAIL-OK-FAIL) by vger.kernel.org with ESMTP id S1732218AbgEMSnA (ORCPT ); Wed, 13 May 2020 14:43:00 -0400 Received: from mail-wm1-x336.google.com (mail-wm1-x336.google.com [IPv6:2a00:1450:4864:20::336]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 8F94FC061A0C for ; Wed, 13 May 2020 11:43:00 -0700 (PDT) Received: by mail-wm1-x336.google.com with SMTP id g14so12513324wme.1 for ; Wed, 13 May 2020 11:43:00 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=subject:to:cc:references:from:message-id:date:user-agent :mime-version:in-reply-to:content-language:content-transfer-encoding; bh=NTHZ/EmLIP+E6b63/qkBsQOKznY5Nc0LePxERT+sG40=; b=EhETGKly6kuyqOSqmqSrUao4vz15YN/LBkRa7dUNII/WmdhkEb/s6r9kfliELLboaG Kg5G0o92en0oNDm2mmR67HmHopu33qZ1LjYDncw3QaYG6yOypV8yGkCDqgVljQ4o8gIW toI/aGVZ1rHqe0rLZ8tnom6TyvdHipuTi6C4dauwelmz/VqVYRSkkA7wngaCo4xgg2qZ 4/v87QBRTza+Xtjmljf+t2wZQVJbd7ACeLu0ywg+JwevO2HyCndajHhNTHqpWxx6bqwy odfqRePUacTQaKtkoLzfJ6MrNJlT59z9rV84EK1TjSxAZSv1p3M3eNt29OlE2t2TFcwC uM5A== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:subject:to:cc:references:from:message-id:date :user-agent:mime-version:in-reply-to:content-language :content-transfer-encoding; bh=NTHZ/EmLIP+E6b63/qkBsQOKznY5Nc0LePxERT+sG40=; b=QkW1lLjIR1a6q3OvCGsqPREPxR4vYECFUiTyv8LDWTCEDDlowESep+F+VHmfzKP64l nSu5wzGy/ZyQyj73bvSrVOogmOwmr66VAiI/lZ29zETXFFphc7qkN3cjTb7G6aJnoLJq BwjXvtCJeWafVGF2gGUNBG8U8mvPUHq+kVzcbV3fLC95jfZIU6/aNeIYVJXVm8UEAJ0V 43yYokg0zgdUUkOaLs76G9tDwa9rin3jRTBEvmfU3cOrC8a5S9YceHLdBr2ZNp6PJU1c Lj06+1nwmcaTfTpdnRrQRtXD8uUPO2Juu++GjPQJIBCTKlHVdpk2BcYkWFI3xrjVr19F DJTw== X-Gm-Message-State: AGi0PuZsioV7CFWRfVTKHumQXykekCXWP2tY6fJE/ZglggK9KVcKCroL bOA4Pn+Ob3lZRGkVnTXGeGeExDZ/ X-Google-Smtp-Source: APiQypKCqBNPjb/EH3rVGDgcO/+lWyv83TIJCCFbLYOlPVpY/nOantl4BW0weuT6zGdwvQPfgrkhiQ== X-Received: by 2002:a1c:99d3:: with SMTP id b202mr45962354wme.126.1589395379379; Wed, 13 May 2020 11:42:59 -0700 (PDT) Received: from ?IPv6:2a00:23c6:9e09:2900:3d38:90c1:858b:902e? ([2a00:23c6:9e09:2900:3d38:90c1:858b:902e]) by smtp.gmail.com with ESMTPSA id n13sm507549wrs.2.2020.05.13.11.42.58 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Wed, 13 May 2020 11:42:58 -0700 (PDT) Subject: Re: x86/smp: adding new trace points To: Thomas Gleixner , linux-kernel@vger.kernel.org Cc: mingo@redhat.com, hpa@zytor.com, x86@kernel.org, Steven Rostedt , Will Deacon References: <4d54953b-f968-63f5-569f-9e09bc0f361c@gmail.com> <87y2pw2fav.fsf@nanos.tec.linutronix.de> <87sgg323bf.fsf@nanos.tec.linutronix.de> From: Wojciech Kudla Message-ID: <56b36edb-1ff8-a154-d3c5-d2304e3554c0@gmail.com> Date: Wed, 13 May 2020 19:42:57 +0100 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:68.0) Gecko/20100101 Thunderbird/68.7.0 MIME-Version: 1.0 In-Reply-To: <87sgg323bf.fsf@nanos.tec.linutronix.de> Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 13/05/2020 17:43, Thomas Gleixner wrote: > Wojciech Kudla writes: >> On 13/05/2020 13:24, Thomas Gleixner wrote: >> >>> Why would the SMP call function single interrupt go through the >>> PLATFORM_IPI_VECTOR? It goes as the name says through the >>> CALL_FUNCTION_SINGLE_VECTOR. >>> >> >> Wrong vector, my bad. >> >> However 2) still stands in my opinion. We don't have "ipi raise" trace >> point for x86. RESCHEDULE_VECTOR, CALL_FUNCTION_SINGLE_VECTOR, as >> well as TLB invalidation vectors are essentially >> inter-processor-interrupts if I'm not mistaken. Would a patch adding >> such trace point be considered here? > > Maybe. > > Though that IPI tracing is inconsistent across architectures. I'm not > really interested to have yet another x86 variant which is slightly > different than anything else. > > ARM and ARM64 share generic tracepoints for that, though the actual > tracepoint invocation is in the architecture specific code. > > If at all we really want to have the common IPIs which are required for > SMP support covered by generic tracepoints and have them in the generic > code and not sprinkled all over arch/* How about we add ipi:ipi_raise trace points before: - arch_send_call_function_single_ipi(), and - arch_send_call_function_ipi_mask() Would that be a good starting point to introduce more generic IPI tracing? Thanks, Wojtek