Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756149Ab2KNAsS (ORCPT ); Tue, 13 Nov 2012 19:48:18 -0500 Received: from mail-pb0-f46.google.com ([209.85.160.46]:57638 "EHLO mail-pb0-f46.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1756041Ab2KNAsP (ORCPT ); Tue, 13 Nov 2012 19:48:15 -0500 Date: Tue, 13 Nov 2012 16:48:11 -0800 From: Greg KH To: Constantine Shulyupin Cc: linux-kernel@vger.kernel.org, celinux-dev@lists.celinuxforum.org Subject: Re: [PATCH] LDT - Linux Driver Template Message-ID: <20121114004811.GA29220@kroah.com> References: <1352832397-1349-1-git-send-email-const@MakeLinux.com> <20121113190123.GA32271@kroah.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.5.21 (2010-09-15) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2091 Lines: 52 On Wed, Nov 14, 2012 at 02:14:58AM +0200, Constantine Shulyupin wrote: > On Tue, Nov 13, 2012 at 9:01 PM, Greg KH wrote: > >> +#define pr_debug_hex(h) pr_debug("%s:%d %s %s = 0x%lX\n", \ > >> + __file__, __LINE__, __func__, #h, (long int)h) > > > > This is not needed at all, just use the proper printk() attribute. > > Macro above allows tidy tracing code: > > pr_debug_hex(ioread8(port_ptr + UART_IER)); > pr_debug_hex(ioread8(port_ptr + UART_IIR)); > pr_debug_hex(ioread8(port_ptr + UART_FCR)); > pr_debug_hex(ioread8(port_ptr + UART_LCR)); > pr_debug_hex(ioread8(port_ptr + UART_MCR)); > pr_debug_hex(ioread8(port_ptr + UART_LSR)); > pr_debug_hex(ioread8(port_ptr + UART_MSR)); > > Without that macro, code above should be rewritten with pr_debug (or printk) as: > > pr_debug("UART_IER=0x%02X\n", ioread8(port_ptr + UART_IER)); > pr_debug("UART_IIR=0x%02X\n", ioread8(port_ptr + UART_IIR)); > pr_debug("UART_FCR=0x%02X\n", ioread8(port_ptr + UART_FCR)); > pr_debug("UART_LCR=0x%02X\n", ioread8(port_ptr + UART_LCR)); > pr_debug("UART_MCR=0x%02X\n", ioread8(port_ptr + UART_MCR)); > pr_debug("UART_LSR=0x%02X\n", ioread8(port_ptr + UART_LSR)); > pr_debug("UART_MSR=0x%02X\n", ioread8(port_ptr + UART_MSR)); > > That is less readable and less supportable. What better is to not do foolish stuff like this at all :) If you need tracing, use the in-kernel tracing framework, don't roll your own. > I prefer the fist case. I prefer the flower case :) > Actually I use a lot shorter macro: > #define traceh(h) printk("%s = 0x%lX\n", #h, (long int)h) > > What is you opinion? Which method is better? Again, neither, don't clutter your code up with unneeded things like this. greg k-h -- 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/