From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-ig0-f173.google.com (mail-ig0-f173.google.com [209.85.213.173]) by kanga.kvack.org (Postfix) with ESMTP id 310DF6B0253 for ; Fri, 31 Jul 2015 14:00:27 -0400 (EDT) Received: by igbpg9 with SMTP id pg9so37061708igb.0 for ; Fri, 31 Jul 2015 11:00:27 -0700 (PDT) Received: from smtprelay.hostedemail.com (smtprelay0223.hostedemail.com. [216.40.44.223]) by mx.google.com with ESMTP id j3si4873996igx.35.2015.07.31.11.00.26 for ; Fri, 31 Jul 2015 11:00:26 -0700 (PDT) Message-ID: <1438365622.19675.97.camel@perches.com> Subject: Re: [PATCH 14/15] mm: Drop unlikely before IS_ERR(_OR_NULL) From: Joe Perches Date: Fri, 31 Jul 2015 11:00:22 -0700 In-Reply-To: <20150731110637.GB899@linux> References: <91586af267deb26b905fba61a9f1f665a204a4e3.1438331416.git.viresh.kumar@linaro.org> <20150731085646.GA31544@node.dhcp.inet.fi> <20150731093450.GA7505@linux> <1438338481.19675.72.camel@perches.com> <20150731110637.GB899@linux> Content-Type: text/plain; charset="ISO-8859-1" Mime-Version: 1.0 Content-Transfer-Encoding: 7bit Sender: owner-linux-mm@kvack.org List-ID: To: Viresh Kumar Cc: yalin wang , "Kirill A. Shutemov" , Andrew Morton , linaro-kernel@lists.linaro.org, open list , "Aneesh Kumar K.V" , David Rientjes , Ebru Akagunduz , Johannes Weiner , "Kirill A. Shutemov" , "open list:MEMORY MANAGEMENT" , Mel Gorman , Michal Hocko , Vlastimil Babka On Fri, 2015-07-31 at 16:36 +0530, Viresh Kumar wrote: > On 31-07-15, 03:28, Joe Perches wrote: > > If it's all fixed, then it's unlikely to be needed in checkpatch. > > I thought checkpatch is more about not committing new mistakes, rather than > finding them in old code. True, but checkpatch is more about style than substance. There are a lot of things that _could_ be added to the script but don't have to be because of relative rarity. The unanswered fundamental though is whether the unlikely use in #define IS_ERR_VALUE is useful. include/linux/err.h:21:#define IS_ERR_VALUE(x) unlikely((x) >= (unsigned long)-MAX_ERRNO) How often does using unlikely here make the code smaller/faster with more recent compilers than gcc 3.4? Or even using gcc 3.4. -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: email@kvack.org