Received: by 2002:a05:6a10:a0d1:0:0:0:0 with SMTP id j17csp345147pxa; Fri, 21 Aug 2020 08:42:41 -0700 (PDT) X-Google-Smtp-Source: ABdhPJyxbC+K77iJU1b0P3Bq/CXQ6bk9fBHTUCXdkRNDqNPtyKzyeY1rGpMe0tDx1S1IgOQWoURi X-Received: by 2002:a05:6402:1593:: with SMTP id c19mr3569420edv.318.1598024561528; Fri, 21 Aug 2020 08:42:41 -0700 (PDT) ARC-Seal: i=1; a=rsa-sha256; t=1598024561; cv=none; d=google.com; s=arc-20160816; b=AelXnpchPPOpgr+sDbIBf6aN6RJPUntEGkgzYPulrsB22HWoh6bPjLmBwvSIpFipGC zO3Rtcj81GPzh++Wtm64f5NT39+9Iscdv7ENcy+K52zFv5Nu4VSPULzJENIAYBv7LEVr dxGK23v+XqJy95zHg/eqm9p9MdGl30cvvlAug0FUAG3Ya+I8zbK+an/QL2bXpqpUipsW Gg7tBSi998Z3a+F4QxEBd+BZpFuI+ceO2gbYYshVpjIE9XK0jqgsJ6JFttGLMJmfCZde JrawAzFx7QS93TySLG+Zpqw2kAccBV1Axmb/yoRTUHXjrK6Pu5WfUPfWirtvflBoRUKE LYpw== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=arc-20160816; h=list-id:precedence:sender:content-transfer-encoding:mime-version :references:in-reply-to:message-id:subject:cc:to:from:date; bh=Mr+A+QO35XYD00dMAdFQKSXTF5ESIzX7ewj2V3EC0r4=; b=Y7l10ZMVXitfec6XnlWVK6UKrRVoHgrkVqtkmBOzHDikxrB6ACtaXSRRa5UVBHLn0V 9MoOOK/W4hM4yjDVuhatsjDIW/yR6um77mbgHc5XJ61Dh79jbx4NHbkwz2VSwBU6dJD5 lRYpcFvVPiwAg1jlk8aGaLRPoQD39938XECV8uSKlxobgqPjzLBWbMBJ0dpXIjn4RO6I VwYMSYutE+wkXGqrCwfxTIB8cNm2kLH16vX7LfKyX1gnxpXqReEg98tuxon7Snd0YgKH 20uP/Du/+qrE56v6A9v9pJc/YnPf3oS2T1Ty+z4B2rcK/Nb8+7gQU1h85uDOzxhrY+0M Knog== ARC-Authentication-Results: i=1; mx.google.com; spf=pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 23.128.96.18 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org Return-Path: Received: from vger.kernel.org (vger.kernel.org. [23.128.96.18]) by mx.google.com with ESMTP id e17si1569606edc.382.2020.08.21.08.42.18; Fri, 21 Aug 2020 08:42:41 -0700 (PDT) Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 23.128.96.18 as permitted sender) client-ip=23.128.96.18; Authentication-Results: mx.google.com; spf=pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 23.128.96.18 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728070AbgHUPlo (ORCPT + 99 others); Fri, 21 Aug 2020 11:41:44 -0400 Received: from mail.kernel.org ([198.145.29.99]:47396 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727849AbgHUPln (ORCPT ); Fri, 21 Aug 2020 11:41:43 -0400 Received: from oasis.local.home (cpe-66-24-58-225.stny.res.rr.com [66.24.58.225]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 9B9092063A; Fri, 21 Aug 2020 15:41:42 +0000 (UTC) Date: Fri, 21 Aug 2020 11:41:41 -0400 From: Steven Rostedt To: Eric Dumazet Cc: Peter Zijlstra , Marco Elver , LKML , David Miller , Jakub Kicinski , netdev Subject: Re: [PATCH] random32: Use rcuidle variant for tracepoint Message-ID: <20200821114141.4b564190@oasis.local.home> In-Reply-To: <20200821113831.340ba051@oasis.local.home> References: <20200821063043.1949509-1-elver@google.com> <20200821085907.GJ1362448@hirez.programming.kicks-ass.net> <20200821113831.340ba051@oasis.local.home> X-Mailer: Claws Mail 3.17.3 (GTK+ 2.24.32; x86_64-pc-linux-gnu) MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Fri, 21 Aug 2020 11:38:31 -0400 Steven Rostedt wrote: > > > At some point we're going to have to introduce noinstr to idle as well. > > > But until that time this should indeed cure things. > > What the above means, is that ideally we will get rid of all tracepoints and kasan checks from these RCU not watching locations. But to do so, we need to move the RCU not watching as close as possible to where it doesn't need to be watching, and that is not as trivial of a task as one might think. Once we get to a minimal code path for RCU not to be watching, it will become "noinstr" and tracing and "debugging" will be disabled in these sections. Peter, please correct the above if it's not accurate. -- Steve