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, URIBL_BLOCKED,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 AF3B4C54FD0 for ; Tue, 21 Apr 2020 13:45:47 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 9072720672 for ; Tue, 21 Apr 2020 13:45:47 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="S/h0HwZw" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728868AbgDUNpr (ORCPT ); Tue, 21 Apr 2020 09:45:47 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:41878 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-FAIL-OK-FAIL) by vger.kernel.org with ESMTP id S1728479AbgDUNpq (ORCPT ); Tue, 21 Apr 2020 09:45:46 -0400 Received: from mail-lj1-x242.google.com (mail-lj1-x242.google.com [IPv6:2a00:1450:4864:20::242]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 5C7E3C061A10 for ; Tue, 21 Apr 2020 06:45:46 -0700 (PDT) Received: by mail-lj1-x242.google.com with SMTP id u6so14047557ljl.6 for ; Tue, 21 Apr 2020 06:45:46 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=from:date:to:cc:subject:message-id:references:mime-version :content-disposition:in-reply-to:user-agent; bh=jgND+vYKjZ2Frd/vEGKk4vcUm9XKaFngOUPSU0cv0iY=; b=S/h0HwZwFEUOfFjkRgVUOVKLt6Rn4vXV8pV6DLmWY+V2SSyLb+aavi18zuOCn0ylM9 tZ4xyWeA2WxL/klZEvZu3CvYvs+/zmjmTiaWAlSJpeDl/jrYUgjiIDiORhrtlAgWQFYC zJ0gGYvS268jSue0xGCFt9pzQYPiTc61QpzAevLcasioylWzZ4JFHo+f+TfGTy1gHsRr qjBmWnqdvXNqQOZ32HI1bRuREnhwasqABQAmEAC1+5d654ACzFEr6eeloe4I6fjHhCdv SrRZqu7Ux6deemycZYpfF2JDCav2qghEJ/PSTWwa/fiB00Uuipe5RZQa3shL8lT63Mfz JKmA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:date:to:cc:subject:message-id:references :mime-version:content-disposition:in-reply-to:user-agent; bh=jgND+vYKjZ2Frd/vEGKk4vcUm9XKaFngOUPSU0cv0iY=; b=uoLaBlxpekpuEf3VxlNs1neznJw/2nurKOlcV0QVURibpH/7qZI6I7YI3nrS+zBs5b 302rhY+OkBJBJe2cjiTbqz/cBsgd8sRmwbXnFaOzD7DBp4v+7dJZliKBVi/36PY4ro3k MaBEr4X+rqFBr2hl/vM7ltg8OV+/dKui0GKZ9VFwT4UDxBEquLmYjqEhphjMKYCo/GVD ur9EuJw/RCTJ9zkC7h4jII+rNS7iPKrkf2ut99Aj4vUxQY10MwupOU5L8uRVDYFMlzU8 cTzsEpA3ZKp8JVL9T6Zzl5vc55zU8Asaf44t16gcMaAOYVgXPNArBcVrzW9FKaQVhmCz jLVA== X-Gm-Message-State: AGi0PubFEhe6DGUS4GognVCLaQHQG8xGGiz6Ts9AXs7JesQnkUxAEj4b RgwNy7O254U4NGx3y+xWFCwtPbQx9ZvEcA== X-Google-Smtp-Source: APiQypK3nVIS0HXF6f5JYZB2ZkwijqJ0GDgwzsOtNZM82GdRPgCtgP+DH+jtzIW0C9XWoHD+mIq0XA== X-Received: by 2002:a2e:9817:: with SMTP id a23mr13843030ljj.71.1587476744849; Tue, 21 Apr 2020 06:45:44 -0700 (PDT) Received: from pc636 (h5ef52e31.seluork.dyn.perspektivbredband.net. [94.245.46.49]) by smtp.gmail.com with ESMTPSA id o25sm2091211lfg.41.2020.04.21.06.45.43 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Tue, 21 Apr 2020 06:45:44 -0700 (PDT) From: Uladzislau Rezki X-Google-Original-From: Uladzislau Rezki Date: Tue, 21 Apr 2020 15:45:37 +0200 To: Steven Rostedt , "Paul E. McKenney" Cc: Uladzislau Rezki , "Paul E. McKenney" , Sebastian Andrzej Siewior , joel@joelfernandes.org, rcu@vger.kernel.org, Josh Triplett , Mathieu Desnoyers , Lai Jiangshan , Thomas Gleixner , Mike Galbraith Subject: Re: [PATCH 1/3] rcu: Use static initializer for krc.lock Message-ID: <20200421134537.GA5952@pc636> References: <20200420164657.GE17661@paulmck-ThinkPad-P72> <20200420165924.GA12078@pc636> <20200420172126.GG17661@paulmck-ThinkPad-P72> <20200420174019.GB12196@pc636> <20200420175915.GH17661@paulmck-ThinkPad-P72> <20200420190650.GA12775@pc636> <20200420201723.GA4192@pc636> <20200420212257.4332734f@oasis.local.home> <20200421051805.GA5124@pc636> <20200421093008.7a0d55ab@gandalf.local.home> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20200421093008.7a0d55ab@gandalf.local.home> User-Agent: Mutt/1.10.1 (2018-07-13) Sender: rcu-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: rcu@vger.kernel.org > Uladzislau Rezki wrote: > > > > > root@pc636:/sys/kernel/debug/tracing# cat set_ftrace_filter > > measure_schedule_delayed_work.constprop.86 > > root@pc636:/sys/kernel/debug/tracing# cat tracing_thresh > > 5 > > root@pc636:/sys/kernel/debug/tracing# cat current_tracer > > function_graph > > root@pc636:/sys/kernel/debug/tracing# > > > > > > Also i set 5 microseconds threshold to filter out what is less > > and added the latency-format trace option. > > Ah, I forgot that tracing_thresh affects function graph tracing. > > The tracing infrastructure has so many features, I can't even keep up ;-) > No problem :) BTW, i decided to perform manual measurement of the schedule_delayed_work() duration, just in case: test PC: laptop with Intel(R) Core(TM) i5-3320M CPU @ 2.60GHz static void noinline measure_schedule_delayed_work(struct kfree_rcu_cpu *krcp) { u64 delta; delta = sched_clock(); schedule_delayed_work(&krcp->monitor_work, KFREE_DRAIN_JIFFIES); delta = sched_clock() - delta; if (delta > 100) trace_printk("-> took %llu nanoseconds.\n", delta); } I get the following figures of taken time: MEDIAN: 831 nanoseconds MAX: 4423 nanoseconds MIN: 123 nanoseconds The data you can find here: ftp://vps418301.ovh.net/incoming/measure_schedule_delayed_work.txt -- Vlad Rezki