From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtprelay0246.hostedemail.com ([216.40.44.246] helo=smtprelay.hostedemail.com) by bombadil.infradead.org with esmtp (Exim 4.80.1 #2 (Red Hat Linux)) id 1XnrYD-0003hY-WA for linux-mtd@lists.infradead.org; Mon, 10 Nov 2014 16:10:46 +0000 Message-ID: <1415635817.8868.6.camel@perches.com> Subject: Re: [PATCH] UBI: Extend UBI layer debug/messaging capabilities - cosmetics From: Joe Perches To: dedekind1@gmail.com Date: Mon, 10 Nov 2014 08:10:17 -0800 In-Reply-To: <1415625297.22887.108.camel@sauron.fi.intel.com> References: <1415531185-2343-1-git-send-email-tlinder@codeaurora.org> <1415621918.22887.80.camel@sauron.fi.intel.com> <5460B553.5060401@codeaurora.org> <1415625297.22887.108.camel@sauron.fi.intel.com> Content-Type: text/plain; charset="ISO-8859-1" Mime-Version: 1.0 Content-Transfer-Encoding: 7bit Cc: Tanya Brokhman , linux-arm-msm@vger.kernel.org, open list , hujianyang@huawei.com, linux-mtd@lists.infradead.org, Brian Norris , David Woodhouse List-Id: Linux MTD discussion mailing list List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , On Mon, 2014-11-10 at 15:14 +0200, Artem Bityutskiy wrote: > On Mon, 2014-11-10 at 14:53 +0200, Tanya Brokhman wrote: > > On 11/10/2014 2:18 PM, Artem Bityutskiy wrote: > > > On Sun, 2014-11-09 at 13:06 +0200, Tanya Brokhman wrote: > > >> > > >> /* Normal UBI messages */ > > >> #define ubi_msg(ubi, fmt, ...) pr_notice("UBI-%d: %s:" fmt "\n", \ > > >> - ubi->ubi_num, __func__, ##__VA_ARGS__) > > >> + (ubi ? ubi->ubi_num : UBI_MAX_DEVICES), \ > > >> + __func__, ##__VA_ARGS__) > > >> /* UBI warning messages */ > > >> #define ubi_warn(ubi, fmt, ...) pr_warn("UBI-%d warning: %s: " fmt "\n", \ > > >> - ubi->ubi_num, __func__, ##__VA_ARGS__) > > >> + (ubi ? ubi->ubi_num : UBI_MAX_DEVICES), \ > > >> + __func__, ##__VA_ARGS__) > > >> /* UBI error messages */ > > >> #define ubi_err(ubi, fmt, ...) pr_err("UBI-%d error: %s: " fmt "\n", \ > > >> - ubi->ubi_num, __func__, ##__VA_ARGS__) > > >> + (ubi ? ubi->ubi_num : UBI_MAX_DEVICES), \ > > >> + __func__, ##__VA_ARGS__) > > > > > > Why did you make these changes? It is preferable to not add another 'if' > > > statement to this macro to handle one or 2 cases - much bloat, little > > > gain. > > > > > > Could we please avoid this? > > > > I just wanted to be on the safe side and prevent this macro being called > > with ubi=NULL that may crash the system. If you still prefer the "if" > > removed will do. > > On the other hand, these are macros, and this if gets duplicated in many > places and translate into few additional assembly instructions per > message. The thing that will make these uses smaller is to convert them to functions. There is a lot of extra duplicated "UBI-%s : " constant string .text added. Using a function uses a single copy of each prefix. The __func__ variable can also be removed. __builtin_return_address(0) may be substituted to save a few more bytes per instance. Something like: (prototype) __printf(2, 3) void ubi_warn(struct ubi *ubi, const char *fmt, ...); (implementation) __printf(2, 3) void ubi_warn(struct ubi *ubi, const char *fmt, ...) { struct va_format vaf; va_list args; int device; va_start(args, format); vaf.fmt = format; vaf.va = &args; if (!ubi) device = UBI_MAX_DEVICE; else device = ubi->ubi_num; pr_warn("UBI-%d warning: %pf: %pV", device, __builtin_return_address(0), &vaf); va_end(args); }