From mboxrd@z Thu Jan 1 00:00:00 1970 From: "J. Bruce Fields" Subject: Re: [PATCH 01/13] vfs: add d_is_dir() Date: Fri, 7 Feb 2014 12:36:36 -0500 Message-ID: <20140207173636.GA8801@fieldses.org> References: <1391791751-2533-1-git-send-email-miklos@szeredi.hu> <1391791751-2533-2-git-send-email-miklos@szeredi.hu> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Cc: viro@ZenIV.linux.org.uk, torvalds@linux-foundation.org, linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org, hch@infradead.org, akpm@linux-foundation.org, dhowells@redhat.com, zab@redhat.com, jack@suse.cz, luto@amacapital.net, mszeredi@suse.cz To: Miklos Szeredi Return-path: Content-Disposition: inline In-Reply-To: <1391791751-2533-2-git-send-email-miklos@szeredi.hu> Sender: linux-kernel-owner@vger.kernel.org List-Id: linux-fsdevel.vger.kernel.org On Fri, Feb 07, 2014 at 05:48:59PM +0100, Miklos Szeredi wrote: > From: Miklos Szeredi > > Add d_is_dir(dentry) helper which is analogous to S_ISDIR(). While trying to get up to speed I notice that these flags were introduced by b18825a7c8e37a7cf6abb97a12a6ad71af160de7 "VFS: Put a small type field into struct dentry::d_flags" whose changelog tells me "what" but not "why". So out of curiosity: was that some kind of optimization, or was there some other reason for it? --b.