From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from relay.sgi.com (relay1.corp.sgi.com [137.38.102.111]) by oss.sgi.com (Postfix) with ESMTP id D345F7F6B for ; Tue, 4 Nov 2014 06:15:20 -0600 (CST) Received: from cuda.sgi.com (cuda3.sgi.com [192.48.176.15]) by relay1.corp.sgi.com (Postfix) with ESMTP id C02708F8037 for ; Tue, 4 Nov 2014 04:15:20 -0800 (PST) Received: from mx1.redhat.com (mx1.redhat.com [209.132.183.28]) by cuda.sgi.com with ESMTP id 28kCVG7XAlFVeUkH (version=TLSv1 cipher=AES256-SHA bits=256 verify=NO) for ; Tue, 04 Nov 2014 04:15:19 -0800 (PST) Date: Tue, 4 Nov 2014 07:15:07 -0500 From: Brian Foster Subject: Re: [PATCH v2 05/17] xfs: create macros/helpers for dealing with sparse inode chunks Message-ID: <20141104121507.GB55611@bfoster.bfoster> References: <1415031146-9107-1-git-send-email-bfoster@redhat.com> <1415031146-9107-6-git-send-email-bfoster@redhat.com> <20141103223407.GA14732@bfoster.bfoster> <20141104013308.GC23575@dastard> MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: <20141104013308.GC23575@dastard> List-Id: XFS Filesystem from SGI List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Errors-To: xfs-bounces@oss.sgi.com Sender: xfs-bounces@oss.sgi.com To: Dave Chinner Cc: Fanael Linithien , xfs@oss.sgi.com On Tue, Nov 04, 2014 at 12:33:08PM +1100, Dave Chinner wrote: > On Tue, Nov 04, 2014 at 12:56:17AM +0100, Fanael Linithien wrote: > > 2014-11-03 23:34 GMT+01:00 Brian Foster : > > > On Mon, Nov 03, 2014 at 11:12:12PM +0100, Fanael Linithien wrote: > > >> 2014-11-03 17:12 GMT+01:00 Brian Foster : > > >> > > > >> > +static inline bool xfs_inobt_issparse(uint16_t holemask) > > >> > +{ > > >> > + return holemask == 0 ? false : true; > > >> > +} > > >> > > >> Surely that should be "return holemask != 0;"? > > >> > > > > > > ir_holemask bits are set for holes in the inode chunk and unset for > > > allocated regions. This means that ir_holemask == 0 for a normal, > > > fully-allocated chunk and != 0 otherwise (some bits are set to indicate > > > the chunk has a hole). Check out the commit log for patch 4 for > > > reasoning. > > > > Oh, I don't comment on the logic, as I don't really know much about > > XFS code. It's purely a stylistic suggestion: "holemask == 0 ? false : > > true" looks entirely equivalent to "holemask != 0". > > Even that is unnecessary. booleans are handled by the > compiler quite nicely - just casting a bool > type will give the same result. i.e. (bool)holemask results in a > value of "false" if holemask is zero, "true" if holemask has any > value other than zero. > > static inline bool xfs_inobt_issparse(uint16_t holemask) > { > return holemask; > } > > Will give the desired result as there is an implicit typecast to > bool in that return statement..... > Indeed, thanks. Brian > Cheers, > > Dave. > -- > Dave Chinner > david@fromorbit.com _______________________________________________ xfs mailing list xfs@oss.sgi.com http://oss.sgi.com/mailman/listinfo/xfs