Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756990AbbHZS1P (ORCPT ); Wed, 26 Aug 2015 14:27:15 -0400 Received: from out4-smtp.messagingengine.com ([66.111.4.28]:42343 "EHLO out4-smtp.messagingengine.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752207AbbHZS1N (ORCPT ); Wed, 26 Aug 2015 14:27:13 -0400 Message-Id: <1440613632.3433387.366841089.60E02F29@webmail.messagingengine.com> X-Sasl-Enc: mzYj8B1Nsf8gy0tiNke67gtbRF0+1hkvp37ySR1SEYc0 1440613632 From: Henrique de Moraes Holschuh To: Joe Perches Cc: Darren Hart , ibm-acpi-devel@lists.sourceforge.net, platform-driver-x86@vger.kernel.org, "linux-kernel" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit Content-Type: text/plain X-Mailer: MessagingEngine.com Webmail Interface - ajax-4500bf93 Subject: Re: [PATCH] thinkpad_acpi: Remove side effects from vdbg_printk -> no_printk macro Date: Wed, 26 Aug 2015 15:27:12 -0300 In-Reply-To: <1440612818.2780.24.camel@perches.com> References: <1440612818.2780.24.camel@perches.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1642 Lines: 41 On Wed, Aug 26, 2015, at 15:13, Joe Perches wrote: > vdbg_printk when not using CONFIG_THINKPAD_ACPI_DEBUG uses > no_printk which produces no logging output but always > evaluates arguments. > > Change the macro to surround the no_printk call with > do { if (0) no_printk(...); } while (0) > to avoid the unnecessary argument evaluations. > > $ size drivers/platform/x86/thinkpad_acpi.o* > text data bss dec hex filename > 60918 6184 824 67926 10956 > drivers/platform/x86/thinkpad_acpi.o.new > 60927 6184 824 67935 1095f > drivers/platform/x86/thinkpad_acpi.o.old The code size savings of this change are really small... > --- a/drivers/platform/x86/thinkpad_acpi.c > +++ b/drivers/platform/x86/thinkpad_acpi.c > @@ -402,7 +402,7 @@ static const char *str_supported(int is_supported); > #else > static inline const char *str_supported(int is_supported) { return ""; } > #define vdbg_printk(a_dbg_level, format, arg...) \ > - no_printk(format, ##arg) > + do { if (0) no_printk(format, ##arg); } while (0) > #endif And won't this change disable compile-time checking of 'format ## arg' for issues? -- "One disk to rule them all, One disk to find them. One disk to bring them all and in the darkness grind them. In the Land of Redmond where the shadows lie." -- The Silicon Valley Tarot Henrique Holschuh -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/