From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753282AbcFJPdL (ORCPT ); Fri, 10 Jun 2016 11:33:11 -0400 Received: from prod-mail-xrelay07.akamai.com ([23.79.238.175]:34844 "EHLO prod-mail-xrelay07.akamai.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752101AbcFJPdJ (ORCPT ); Fri, 10 Jun 2016 11:33:09 -0400 Subject: Re: [PATCH v2 4/4] dynamic_debug: add jump label support To: Arnd Bergmann References: <587263b37406eda0d2ab84874a9fd4c81eaeca1d.1463778029.git.jbaron@akamai.com> <3796097.4dlb9d7Id8@wuerfel> CC: , , , From: Jason Baron Message-ID: <575ADDB3.7070304@akamai.com> Date: Fri, 10 Jun 2016 11:33:07 -0400 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:38.0) Gecko/20100101 Thunderbird/38.7.2 MIME-Version: 1.0 In-Reply-To: <3796097.4dlb9d7Id8@wuerfel> Content-Type: text/plain; charset="windows-1252" Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 06/10/2016 05:54 AM, Arnd Bergmann wrote: > On Friday, May 20, 2016 5:16:36 PM CEST Jason Baron wrote: >> Although dynamic debug is often only used for debug builds, sometimes its >> enabled for production builds as well. Minimize its impact by using jump >> labels. This reduces the text section by 7000+ bytes in the kernel image >> below. It does increase data, but this should only be referenced when >> changing the direction of the branches, and hence usually not in cache. >> >> text data bss dec hex filename >> 8194852 4879776 925696 14000324 d5a0c4 vmlinux.pre >> 8187337 4960224 925696 14073257 d6bda9 vmlinux.post >> >> Signed-off-by: Jason Baron >> --- > > This causes problems for some of my randconfig builds, when a dynamic > debug call is used inside of an __exit function: > > `.exit.text' referenced in section `__jump_table' of drivers/built-in.o: defined in discarded section `.exit.text' of drivers/built-in.o > `.exit.text' referenced in section `__jump_table' of drivers/built-in.o: defined in discarded section `.exit.text' of drivers/built-in.o > > Arnd > Hi, I stuck pr_debug() in a few functions marked with __exit, but did not reproduce yet. Can you share your .config and gcc --version. Thanks, -Jason