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=-5.2 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, USER_AGENT_SANE_2 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 D1567C433E3 for ; Fri, 21 Aug 2020 15:41:46 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id B16212063A for ; Fri, 21 Aug 2020 15:41:46 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728082AbgHUPlo (ORCPT ); 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: netdev-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: netdev@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