From mboxrd@z Thu Jan 1 00:00:00 1970 From: Abhijit Pawar Subject: Re: [RESEND PATCH] fs/super.c set_anon_super calling optimization Date: Fri, 30 Nov 2012 11:10:02 +0530 Message-ID: <50B846B2.9040700@gmail.com> References: <508924AB.4060902@gmail.com> <20121026131441.GA22256@andromeda.usersys.redhat.com> <20121130040556.GD4939@ZenIV.linux.org.uk> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Cc: Abhijit Pawar , linux-fsdevel@vger.kernel.org, "linux-btrfs@vger.kernel.org" , linux-kernel@vger.kernel.org, gregkh@linuxfoundation.org To: Al Viro Return-path: In-Reply-To: <20121130040556.GD4939@ZenIV.linux.org.uk> Sender: linux-kernel-owner@vger.kernel.org List-Id: linux-fsdevel.vger.kernel.org On 11/30/2012 09:35 AM, Al Viro wrote: > On Fri, Oct 26, 2012 at 11:14:41AM -0200, Carlos Maiolino wrote: >> Hi, >> >> On Thu, Oct 25, 2012 at 05:08:19PM +0530, Abhijit Pawar wrote: >>> Hi, >>> set_anon_super is called by many filesystems. Some call directly and >>> some call through the wrapper. Many of them in the wrapper's call to >>> this function are passing the second argument to this function which >>> is not used anywhere. >>> >>> This patch replaces the second variable with NULL. >>> >> >> If the variable isn't used anymore, why don't just get rid of it, instead of >> call the function passing a NULL pointer on it? > > Because we want it to be a valid sget() callback. I doubt that this > optimization is worth doing, though - might even micro-pessimize the things > on architectures where all arguments are passed in registers. > Al, Yes. it will be helpful in registers case. -- - Abhijit