From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754546AbaLDPhT (ORCPT ); Thu, 4 Dec 2014 10:37:19 -0500 Received: from mail-qc0-f173.google.com ([209.85.216.173]:42798 "EHLO mail-qc0-f173.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753880AbaLDPhR (ORCPT ); Thu, 4 Dec 2014 10:37:17 -0500 Message-ID: <54807FC3.9050305@gmail.com> Date: Thu, 04 Dec 2014 10:37:39 -0500 From: Pranith Kumar User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:31.0) Gecko/20100101 Thunderbird/31.2.0 MIME-Version: 1.0 To: paulmck@linux.vnet.ibm.com CC: linux-kernel@vger.kernel.org, Josh Triplett Subject: Re: [RFC PATCH v2] tinification: Introduce CONFIG_SRCU to make SRCU optional References: <1417665832-6933-1-git-send-email-bobby.prani@gmail.com> <20141204062704.GH25340@linux.vnet.ibm.com> In-Reply-To: <20141204062704.GH25340@linux.vnet.ibm.com> Content-Type: text/plain; charset=windows-1252 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 12/04/2014 01:27 AM, Paul E. McKenney wrote: > For the moment, I applied this to -rcu against v3.18-rc6 to get some 0day > testing on it. > > There are conflicts against the tip of my tree, but will worry about > that later. I don't have a ready answer on whether or not this needs > to be split up -- in the worst case, we would add the SRCU Kconfig > parameter, add all the selects, then once they all hit mainline add the > Makefile change. > > We will need stats on how much memory was saved, and a "size kernel/rcu/srcu.o" > after a UP/tiny build should do it. Could you please add this to the > commit log? > So if we do not select CONFIG_SRCU, srcu.o will not be compiled at all. So we should save about text data bss dec hex filename 2007 0 0 2007 7d7 kernel/rcu/srcu.o as in size of arch/powerpc/boot/zImage changes from text data bss dec hex filename 831552 64180 23944 919676 e087c arch/powerpc/boot/zImage : before 829504 64180 23952 917636 e0084 arch/powerpc/boot/zImage : after so about ~2000 bytes I guess. -- Pranith