Received: by 2002:a05:7412:40d:b0:e2:908c:2ebd with SMTP id 13csp433154rdf; Tue, 21 Nov 2023 06:44:40 -0800 (PST) X-Google-Smtp-Source: AGHT+IGlEJK9RtYAe5XQG6HWdIfkcriTXs6E/vOH4NKd0gTuMtFl+xJqphNrHsvPbrUWmD547AgZ X-Received: by 2002:a05:6a20:5498:b0:18a:f4f6:bba5 with SMTP id i24-20020a056a20549800b0018af4f6bba5mr1420236pzk.0.1700577880681; Tue, 21 Nov 2023 06:44:40 -0800 (PST) ARC-Seal: i=1; a=rsa-sha256; t=1700577880; cv=none; d=google.com; s=arc-20160816; b=CtKoTFi8/as0JiNJIF81aH29j53AJW+B5O9vRudJmuvZK+L2ec4qKQmuTR5IlEgLVA QOwxlSJdvHjNCRXBGZhE0inzUrdFAP6GqhSjGvhgqLoQ1nhVPlskzV1KWRn7gaGvo3vh RVKjtMOQGKwFBPBMaWTmeVo8qyRcY9loQDbueM4Gr0UuDwKLQC2VGpkQMAhV22ryX859 CU1IDTb8wIMZRhz52KN35cahBTFpgFxwqJ+TkOFiwdMLPaZ7OCNJANmsFPrOTIzVqmC0 rCDXzz2q6Sff8Uv1kRVTqG9Og4C1a2ILJC4xENARGkaBAcwTEuDeT3ECMTghcRWSfS3n 3heg== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=arc-20160816; h=list-id:precedence:content-transfer-encoding:mime-version :references:in-reply-to:message-id:subject:cc:to:from:date; bh=57Kxafap0N4wXA7bvJTz9jP55qKHCuS8FCUMstYZxsU=; fh=pKI1RiOYM1btNMoqtCOtEG2EnSydeSwTW9LxIfTVnBA=; b=IAKGO8nQzOCAlJv04l+92LlwG2+b6YIO1VuCEolT8D73UGaFzgWpcVz1sxaY4B5PW7 bfaM+EtPg/K6RX+nESYh852G/A0p4pvVNtIaNAVOFpM+LXhzZfAUXjbihLYXzPJApJtd 4cqgPbdGmvqO/W0qjavPcD2mXHtYdapB32QnhW+51pLw45EcucTJnB1w6ai2FU8ufFAM PDDq0cEUe84Cs33qBQoe48fzVqoaj/iFCOh/KHzwTGQxr7CAvX072RwKRHZeTh2MFxDO cBJrj+veb5bHV16+d1W+DvTJj9bSw9lG/zACPWTRE+rZpU63iF3zdgFcAJyV3yrPLcqW pmNw== ARC-Authentication-Results: i=1; mx.google.com; spf=pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 2620:137:e000::3:7 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org Return-Path: Received: from snail.vger.email (snail.vger.email. [2620:137:e000::3:7]) by mx.google.com with ESMTPS id u11-20020a170902e80b00b001c73732c1f2si11066901plg.223.2023.11.21.06.44.40 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Tue, 21 Nov 2023 06:44:40 -0800 (PST) Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 2620:137:e000::3:7 as permitted sender) client-ip=2620:137:e000::3:7; Authentication-Results: mx.google.com; spf=pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 2620:137:e000::3:7 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: from out1.vger.email (depot.vger.email [IPv6:2620:137:e000::3:0]) by snail.vger.email (Postfix) with ESMTP id 78D498131A88; Tue, 21 Nov 2023 06:44:39 -0800 (PST) X-Virus-Status: Clean X-Virus-Scanned: clamav-milter 0.103.11 at snail.vger.email Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S234739AbjKUOoh (ORCPT + 99 others); Tue, 21 Nov 2023 09:44:37 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:33914 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S234295AbjKUOof (ORCPT ); Tue, 21 Nov 2023 09:44:35 -0500 Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id A40559E for ; Tue, 21 Nov 2023 06:44:31 -0800 (PST) Received: by smtp.kernel.org (Postfix) with ESMTPSA id A5174C433C8; Tue, 21 Nov 2023 14:44:29 +0000 (UTC) Date: Tue, 21 Nov 2023 09:44:44 -0500 From: Steven Rostedt To: Peter Zijlstra Cc: Mathieu Desnoyers , "Paul E. McKenney" , Masami Hiramatsu , linux-kernel@vger.kernel.org, Michael Jeanson , Alexei Starovoitov , Yonghong Song , Ingo Molnar , Arnaldo Carvalho de Melo , Mark Rutland , Alexander Shishkin , Jiri Olsa , Namhyung Kim , bpf@vger.kernel.org, Joel Fernandes Subject: Re: [PATCH v4 1/5] tracing: Introduce faultable tracepoints Message-ID: <20231121094444.04701bdc@gandalf.local.home> In-Reply-To: <20231121143647.GI8262@noisy.programming.kicks-ass.net> References: <20231120205418.334172-1-mathieu.desnoyers@efficios.com> <20231120205418.334172-2-mathieu.desnoyers@efficios.com> <20231120214742.GC8262@noisy.programming.kicks-ass.net> <62c6e37c-88cc-43f7-ac3f-1c14059277cc@paulmck-laptop> <20231120222311.GE8262@noisy.programming.kicks-ass.net> <20231121084706.GF8262@noisy.programming.kicks-ass.net> <20231121143647.GI8262@noisy.programming.kicks-ass.net> X-Mailer: Claws Mail 3.19.1 (GTK+ 2.24.33; x86_64-pc-linux-gnu) MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit X-Spam-Status: No, score=-4.0 required=5.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,RCVD_IN_DNSWL_MED,SPF_HELO_NONE,SPF_PASS, T_SCC_BODY_TEXT_LINE autolearn=ham autolearn_force=no version=3.4.6 X-Spam-Checker-Version: SpamAssassin 3.4.6 (2021-04-09) on lindbergh.monkeyblade.net Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org X-Greylist: Sender passed SPF test, not delayed by milter-greylist-4.6.4 (snail.vger.email [0.0.0.0]); Tue, 21 Nov 2023 06:44:39 -0800 (PST) On Tue, 21 Nov 2023 15:36:47 +0100 Peter Zijlstra wrote: > > Still utterly confused about what task-tracing rcu is and how it is > different from preemptible rcu. Is this similar to synchronize_rcu_tasks()? As I understand that one (grace period continues until all tasks have voluntarily scheduled or gone into user space). But I'm a bit confused by synchronize_rcu_tasks_trace()? Note, that for syncronize_rcu_tasks() the critical sections must not call schedule (although it is OK to be preempted). -- Steve