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 672F6C433F5 for ; Sat, 23 Apr 2022 09:43:37 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S234620AbiDWJqb (ORCPT ); Sat, 23 Apr 2022 05:46:31 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:43902 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S234355AbiDWJqY (ORCPT ); Sat, 23 Apr 2022 05:46:24 -0400 Received: from mail-lf1-x129.google.com (mail-lf1-x129.google.com [IPv6:2a00:1450:4864:20::129]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 59718F99C6; Sat, 23 Apr 2022 02:43:27 -0700 (PDT) Received: by mail-lf1-x129.google.com with SMTP id p12so12658766lfs.5; Sat, 23 Apr 2022 02:43:27 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20210112; h=mime-version:references:in-reply-to:from:date:message-id:subject:to :cc; bh=oUBbhwe77dvZymIbzfQlDVdZ71HesftAxXVr2puB39s=; b=JJ0iSM3VYZoIZRIpbt+qdyzSNtOQgywj8kqmG8PHbdUkOo1KGNeb12i8bAo5u70z+g MZlgZxP1EneHa0ustMXWUaJhX43t0t7YNKNQ9vT+dHe+Ou16NacALKuV6sp1Wb/FjBE8 x7ygmXnhuQDSBvdntnLZ1cQ0N3lvVaxoKWBTxw8eK68Ld/iywY+MUEsTIwWjUSf7Mb3s PsdP1LXHd3e6QviWp1u0CFm4op8u49bnJxJVttFXIEviXfXNOzAyAdzJjsOLThr5mNOB D6Us1ANF7hGKl1m30NOrVr6oDirV3Ow8BpF98EMpOWI0s8t5L4Jtqamb6mkcg/x+TKl2 Nlkg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:mime-version:references:in-reply-to:from:date :message-id:subject:to:cc; bh=oUBbhwe77dvZymIbzfQlDVdZ71HesftAxXVr2puB39s=; b=FMfM+GVG7y50x8DQuGV7uGpdA0eYn1vtjER4wnRqpqfIcS7GUD9s03rZg5AMpqRPMo r9/Rs3YwLDJOAsGzvaFF4IJHAUAu3A5sucbUcIT3CjMjqF1P+O1Tr+hFC4mcaf4Uieac F+eYxVTULvYSD+Mm+5W9+QV/L4RAlI/j3+CZIXSXLwyLTsuF6hWa/SmbKGv7XeNB+Gnv OnqFkawTfuKxmI9rpxepXx6tDPfXsKDP91wKLOlkKDGCjBBaMADTQn6qXhm16hEe6CzK ALKIl9CzgzZl7JENQNZhJu3yCeRSThoKp8BDncGwIdJq/0saNzBQxWiSBHFci6VNOUT8 nc4Q== X-Gm-Message-State: AOAM532L8qnjj+oW8Z+ZHB0r0681Rx6WQBpPY6gYJEBbGZhIR9FbDPNT hSWc/wbD4pmYbUzsCT5IIqa7z4+4b0aiMf5A4cLtmUI0Wpw= X-Google-Smtp-Source: ABdhPJx3PiAC4IN3QA9lLfbfNKn0dxG4BswJ6Gg/KxmIdi8iEhBA2vkKHLCN9u7rTYARgcOzD0Rd2Yol9EVH3M2fhm8= X-Received: by 2002:a05:6512:400e:b0:450:e09d:c9a6 with SMTP id br14-20020a056512400e00b00450e09dc9a6mr6411283lfb.243.1650707005488; Sat, 23 Apr 2022 02:43:25 -0700 (PDT) MIME-Version: 1.0 References: <20220418043735.11441-1-patrick.wang.shcn@gmail.com> <20220418143404.55c8fcab@gandalf.local.home> <20220420114454.69ab108c@gandalf.local.home> <20220420122633.55d4ff6b@gandalf.local.home> <20220421085047.2cb8edf9@gandalf.local.home> <20220422115234.613436e4@gandalf.local.home> In-Reply-To: <20220422115234.613436e4@gandalf.local.home> From: patrick wang Date: Sat, 23 Apr 2022 17:43:14 +0800 Message-ID: Subject: Re: [PATCH] rcu: ftrace: avoid tracing a few functions executed in multi_cpu_stop() To: Steven Rostedt Cc: paulmck@kernel.org, frederic@kernel.org, quic_neeraju@quicinc.com, josh@joshtriplett.org, mathieu.desnoyers@efficios.com, jiangshanlai@gmail.com, joel@joelfernandes.org, rcu@vger.kernel.org, linux-kernel@vger.kernel.org Content-Type: text/plain; charset="UTF-8" Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Fri, Apr 22, 2022 at 11:52 PM Steven Rostedt wrote: > > On Fri, 22 Apr 2022 18:45:46 +0800 > patrick wang wrote: > > > Yes, and not just RISC-V. It's arch-independent. It's the internal change of > > stop machine implementation. > > > > ---------------------------------------------------------------- > > Former stop machine wait loop: > > do { > > cpu_relax(); => macro > > ... > > } while (curstate != STOPMACHINE_EXIT); > > ----------------------------------------------------------------- > > Current stop machine wait loop: > > do { > > stop_machine_yield(cpumask); => function (notraced) > > ... > > touch_nmi_watchdog(); => function (notraced, inside calls also notraced) > > ... > > rcu_momentary_dyntick_idle(); => function (notraced, inside calls traced) > > } while (curstate != MULTI_STOP_EXIT); > > ------------------------------------------------------------------ > > That makes much more sense. Can you add that to the change log. > Sure, I will rewrite the log message. And thank you for the comments and advices. Thanks, Patrick > Reviewed-by: Steven Rostedt (Google) > > -- Steve