From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932964AbcHVQqZ (ORCPT ); Mon, 22 Aug 2016 12:46:25 -0400 Received: from mga09.intel.com ([134.134.136.24]:49846 "EHLO mga09.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932808AbcHVQqU (ORCPT ); Mon, 22 Aug 2016 12:46:20 -0400 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.28,560,1464678000"; d="scan'208";a="594972" Date: Mon, 22 Aug 2016 09:46:04 -0700 From: "Luck, Tony" To: Joe Perches Cc: Doug Thompson , Borislav Petkov , Mauro Carvalho Chehab , linux-edac@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH] skx_edac: Move a few hundred bytes to text from data using const Message-ID: <20160822164603.GA24307@intel.com> References: <8edda9e0b7357f5177d9f3bb536a71025379f9cb.1471824129.git.joe@perches.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <8edda9e0b7357f5177d9f3bb536a71025379f9cb.1471824129.git.joe@perches.com> User-Agent: Mutt/1.5.23 (2014-03-12) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Sun, Aug 21, 2016 at 05:02:41PM -0700, Joe Perches wrote: > Marking arrays as const makes for smaller data. Joe, "a few hundred" seems to be exaggeration. Before: $ size drivers/edac/skx_edac.ko text data bss dec hex filename 8435 1024 24 9483 250b drivers/edac/skx_edac.ko After: $ size drivers/edac/skx_edac.ko text data bss dec hex filename 8531 944 24 9499 251b drivers/edac/skx_edac.ko so "data" was reduced by 80 bytes, but "text" went up by 96. Net increase of 16 (perhaps because some padding for alignment???) Making read-only data const is a good idea in general, but do we want to do it if it *increases* kernel footprint? -Tony