From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1760862AbYDTKnL (ORCPT ); Sun, 20 Apr 2008 06:43:11 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1751134AbYDTKkO (ORCPT ); Sun, 20 Apr 2008 06:40:14 -0400 Received: from pentafluge.infradead.org ([213.146.154.40]:56272 "EHLO pentafluge.infradead.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1758265AbYDTKkM (ORCPT ); Sun, 20 Apr 2008 06:40:12 -0400 From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Joe Perches , Greg Kroah-Hartman Subject: [PATCH 10/36] driver core: Convert debug functions declared inline __attribute__((format (printf,x,y) to statement expression macros Date: Sun, 20 Apr 2008 03:45:40 -0700 Message-Id: <1208688366-9252-10-git-send-email-gregkh@suse.de> X-Mailer: git-send-email 1.5.4.5 In-Reply-To: <20080420104516.GA9225@suse.de> References: <20080420104516.GA9225@suse.de> X-Bad-Reply: References and In-Reply-To but no 'Re:' in Subject. Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Joe Perches When DEBUG is not defined, pr_debug and dev_dbg and some other local debugging functions are specified as: "inline __attribute__((format (printf, x, y)))" This is done to validate printk arguments when not debugging. Converting these functions to macros or statement expressions "do { if (0) printk(fmt, ##arg); } while (0)" or "({ if (0) printk(fmt, ##arg); 0; }) makes at least gcc 4.2.2 produce smaller objects. This has the additional benefit of allowing the optimizer to avoid calling functions like print_mac that might have been arguments to the printk. defconfig x86 current: $ size vmlinux text data bss dec hex filename 4716770 474560 618496 5809826 58a6a2 vmlinux all converted: (More patches follow) $ size vmlinux text data bss dec hex filename 4716642 474560 618496 5809698 58a622 vmlinux Even kernel/sched.o, which doesn't even use these functions, becomes smaller. It appears that merely having an indirect include of can cause bigger objects. $ size sched.inline.o sched.if0.o text data bss dec hex filename 31385 2854 328 34567 8707 sched.inline.o 31366 2854 328 34548 86f4 sched.if0.o The current preprocessed only kernel/sched.i file contains: # 612 "include/linux/device.h" static inline __attribute__((always_inline)) int __attribute__ ((format (printf, 2, 3))) dev_dbg(struct device *dev, const char *fmt, ...) { return 0; } # 628 "include/linux/device.h" static inline __attribute__((always_inline)) int __attribute__ ((format (printf, 2, 3))) dev_vdbg(struct device *dev, const char *fmt, ...) { return 0; } Removing these unused inlines from sched.i shrinks sched.o Signed-off-by: Joe Perches Signed-off-by: Greg Kroah-Hartman --- include/linux/device.h | 15 +++++---------- include/linux/kernel.h | 6 ++---- 2 files changed, 7 insertions(+), 14 deletions(-) diff --git a/include/linux/device.h b/include/linux/device.h index 2258d89..d576611 100644 --- a/include/linux/device.h +++ b/include/linux/device.h @@ -608,21 +608,16 @@ extern const char *dev_driver_string(struct device *dev); #define dev_dbg(dev, format, arg...) \ dev_printk(KERN_DEBUG , dev , format , ## arg) #else -static inline int __attribute__ ((format (printf, 2, 3))) -dev_dbg(struct device *dev, const char *fmt, ...) -{ - return 0; -} +#define dev_dbg(dev, format, arg...) \ + ({ if (0) dev_printk(KERN_DEBUG, dev, format, ##arg); 0; }) #endif #ifdef VERBOSE_DEBUG #define dev_vdbg dev_dbg #else -static inline int __attribute__ ((format (printf, 2, 3))) -dev_vdbg(struct device *dev, const char *fmt, ...) -{ - return 0; -} + +#define dev_vdbg(dev, format, arg...) \ + ({ if (0) dev_printk(KERN_DEBUG, dev, format, ##arg); 0; }) #endif /* Create alias, so I can be autoloaded. */ diff --git a/include/linux/kernel.h b/include/linux/kernel.h index 2df44e7..cd6d02c 100644 --- a/include/linux/kernel.h +++ b/include/linux/kernel.h @@ -293,10 +293,8 @@ extern void print_hex_dump_bytes(const char *prefix_str, int prefix_type, #define pr_debug(fmt, arg...) \ printk(KERN_DEBUG fmt, ##arg) #else -static inline int __attribute__ ((format (printf, 1, 2))) pr_debug(const char * fmt, ...) -{ - return 0; -} +#define pr_debug(fmt, arg...) \ + ({ if (0) printk(KERN_DEBUG fmt, ##arg); 0; }) #endif /* -- 1.5.4.5