From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754665AbdJSQEG (ORCPT ); Thu, 19 Oct 2017 12:04:06 -0400 Received: from mail-oi0-f68.google.com ([209.85.218.68]:52622 "EHLO mail-oi0-f68.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752213AbdJSQEE (ORCPT ); Thu, 19 Oct 2017 12:04:04 -0400 X-Google-Smtp-Source: ABhQp+RmBrfkueIahWUwnqpyrT1JkddRjtuCdNTa3ixx4Nqj2xliYKWNrjTfRe8Mz/YdQM3FmSTFLUrRi2VxZfZk7L4= MIME-Version: 1.0 In-Reply-To: References: <20171019083230.2450779-1-arnd@arndb.de> From: Arnd Bergmann Date: Thu, 19 Oct 2017 18:04:03 +0200 X-Google-Sender-Auth: ODH2W6rQJinfiwsVo1mLgsXiaNY Message-ID: Subject: Re: [PATCH] tracing: always define trace_{irq,preempt}_{enable_disable} To: Joel Fernandes Cc: Steven Rostedt , Ingo Molnar , LKML Content-Type: text/plain; charset="UTF-8" Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Thu, Oct 19, 2017 at 5:42 PM, Joel Fernandes wrote: > Hi Arnd, > > On Thu, Oct 19, 2017 at 1:32 AM, Arnd Bergmann wrote: >> We get a build error in the irqsoff tracer in some configurations: >> >> kernel/trace/trace_irqsoff.c: In function 'trace_preempt_on': >> kernel/trace/trace_irqsoff.c:855:2: error: implicit declaration of function 'trace_preempt_enable_rcuidle'; did you mean 'trace_irq_enable_rcuidle'? [-Werror=implicit-function-declaration] >> trace_preempt_enable_rcuidle(a0, a1); >> >> The problem is that trace_preempt_enable_rcuidle() has different >> definition based on multiple Kconfig symbols, but not all combinations >> have a valid definition. >> >> This changes the conditions so that we always get exactly one >> definition of each of the four tracing macros. I have not tried >> to verify that these definitions are sensible, but now we >> can build all randconfig combinations again. >> > > Thanks for catching this. I didn't follow why it breaks for you, > especially I'm troubled by your proposal of defining the empty macro > for !defined(CONFIG_DEBUG_PREEMPT) in your patch. Could you provide > your config sample and architecture you're building for? I'm guessing > its ARM but let me know. I will try to build it and reproduce it. I ran into it during an arm64 randconfig build, uploaded the config file to https://pastebin.com/s5AiqXTM Arnd > thanks, > Joel