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=-2.4 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_PASS, USER_AGENT_MUTT autolearn=ham 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 43CE5ECDFB1 for ; Tue, 17 Jul 2018 20:15:05 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id F169C20693 for ; Tue, 17 Jul 2018 20:15:04 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=joelfernandes.org header.i=@joelfernandes.org header.b="DcEw8uQM" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org F169C20693 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=joelfernandes.org Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1731058AbeGQUtS (ORCPT ); Tue, 17 Jul 2018 16:49:18 -0400 Received: from mail-pg1-f195.google.com ([209.85.215.195]:33737 "EHLO mail-pg1-f195.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1729952AbeGQUtR (ORCPT ); Tue, 17 Jul 2018 16:49:17 -0400 Received: by mail-pg1-f195.google.com with SMTP id r5-v6so923082pgv.0 for ; Tue, 17 Jul 2018 13:15:02 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=joelfernandes.org; s=google; h=date:from:to:cc:subject:message-id:references:mime-version :content-disposition:in-reply-to:user-agent; bh=PwgDAJA/ohGeic0rELg9CJVSIdskMcxdnYJzKJHcmJs=; b=DcEw8uQMjQdoSQErx6e+gLiNFN1RIp7n3eGPNAdao6LRi6QeROv6qwS3jt494KMqj6 0maWF6n55gO+REstTJVe2vYKuYuMIboO6CJjgE1AYu9LPkP8CH5LkYxlSuOOLVT+ZN/O XjHUMsZChafUEjfMObIk8Ia2WyZK9/85rDnr0= X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:date:from:to:cc:subject:message-id:references :mime-version:content-disposition:in-reply-to:user-agent; bh=PwgDAJA/ohGeic0rELg9CJVSIdskMcxdnYJzKJHcmJs=; b=n+fQarWVD12u5YXjSkPDq0owQ46rFc8Uhqxsml0gSOuy4Y5CD2OfSL0PoyTF1gYATM sGVl+vDsF7FHy8ZUr0JGDshGyJWxo3RO71ezyzHOlk8nNXYwHeX9xR2tvCwgkL2HJFpa 6IEO4OxmcxN0vy8eJDVDo7df4fpFPGH7RYy0nuIifZC4AB6OBnSyNdf6knqsKe85hCF1 4FbeSXuvbsMfg6vhMFbk4tCJ0ok/nTJ5BKK+YbYB4UcM6xx25JArNy5wYkGglPvumW2Q 3w/5cRoPck5J8wfBq2fMgX2QZkWx6sqkwCJ1VpWu/xnN6loJygEEwF/2YiWe/2pql9LH k2Uw== X-Gm-Message-State: AOUpUlEBO92AVGh0qri45pRnc/ULZmSjvhJvX65nLtg7z8ctNp4rMF1Q NPX2adWO9frOkW22SqR5e43hVw== X-Google-Smtp-Source: AAOMgpdBq9XqzzqAXnxvIOibTOeJGiLcM4LN0PP3HGOce9sYE4z00Nrfr1zLChKTaDg+Sxc30XSYaQ== X-Received: by 2002:a63:4306:: with SMTP id q6-v6mr2829794pga.181.1531858502000; Tue, 17 Jul 2018 13:15:02 -0700 (PDT) Received: from localhost ([2620:0:1000:1600:3122:ea9c:d178:eb]) by smtp.gmail.com with ESMTPSA id l4-v6sm2389333pgn.46.2018.07.17.13.15.01 (version=TLS1_2 cipher=ECDHE-RSA-CHACHA20-POLY1305 bits=256/256); Tue, 17 Jul 2018 13:15:01 -0700 (PDT) Date: Tue, 17 Jul 2018 13:15:00 -0700 From: Joel Fernandes To: Peter Zijlstra Cc: linux-kernel@vger.kernel.org, kernel-team@android.com, Boqun Feng , Byungchul Park , Erick Reyes , Ingo Molnar , Julia Cartwright , Masami Hiramatsu , Mathieu Desnoyers , Namhyung Kim , Paul McKenney , Steven Rostedt , Thomas Glexiner , Todd Kjos , Tom Zanussi , Will Deacon Subject: Re: [PATCH v10 2/3] tracepoint: Make rcuidle tracepoint callers use SRCU Message-ID: <20180717201500.GA164758@joelaf.mtv.corp.google.com> References: <20180713215547.255620-1-joel@joelfernandes.org> <20180713215547.255620-3-joel@joelfernandes.org> <20180717182528.GK2494@hirez.programming.kicks-ass.net> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20180717182528.GK2494@hirez.programming.kicks-ass.net> User-Agent: Mutt/1.9.2 (2017-12-15) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Tue, Jul 17, 2018 at 08:25:28PM +0200, Peter Zijlstra wrote: > On Fri, Jul 13, 2018 at 02:55:46PM -0700, Joel Fernandes wrote: > > + /* keep srcu and sched-rcu usage consistent */ \ > > + preempt_disable_notrace(); \ > > + \ > > + /* \ > > + * For rcuidle callers, use srcu since sched-rcu \ > > + * doesn't work from the idle path. \ > > + */ \ > > + if (rcuidle) \ > > + idx = srcu_read_lock_notrace(&tracepoint_srcu); \ > > + else \ > > + rcu_read_lock_sched_notrace(); \ > > That else is completely superfluous. rcu_read_lock_sched_notrace() := > prempt_disable_notrace(). Yes, sorry I missed this in your original idea. Will do it this way and repost. Thanks Peter! - Joel