Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752934Ab1FNSXq (ORCPT ); Tue, 14 Jun 2011 14:23:46 -0400 Received: from lennier.cc.vt.edu ([198.82.162.213]:44002 "EHLO lennier.cc.vt.edu" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752017Ab1FNSXn (ORCPT ); Tue, 14 Jun 2011 14:23:43 -0400 X-Mailer: exmh version 2.7.2 01/07/2005 with nmh-1.3-dev To: Jean Sacren Cc: "H. Peter Anvin" , Linux Kernel Mailing List Subject: Re: [PATCH 1/1] boot: Enhance performance by eliminating unnecessary calls to printf() In-Reply-To: Your message of "Sun, 12 Jun 2011 12:36:28 MDT." <20110612183627.GA12311@mail.gmail.com> From: Valdis.Kletnieks@vt.edu References: <20110606004038.GA28970@mail.gmail.com> <4DED0990.8090309@linux.intel.com> <20110612183627.GA12311@mail.gmail.com> Mime-Version: 1.0 Content-Type: multipart/signed; boundary="==_Exmh_1308075820_2718P"; micalg=pgp-sha1; protocol="application/pgp-signature" Content-Transfer-Encoding: 7bit Date: Tue, 14 Jun 2011 14:23:40 -0400 Message-ID: <55695.1308075820@turing-police.cc.vt.edu> X-Mirapoint-Received-SPF: 198.82.161.152 auth3.smtp.vt.edu Valdis.Kletnieks@vt.edu 2 pass X-Junkmail-Info: (0) X-Junkmail-Status: score=10/50, host=steiner.cc.vt.edu X-Junkmail-Signature-Raw: score=unknown, refid=str=0001.0A020204.4DF7A72C.01DA,ss=1,fgs=0, ip=0.0.0.0, so=2010-07-22 22:03:31, dmn=2009-09-10 00:05:08, mode=multiengine X-Junkmail-IWF: false Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1324 Lines: 40 --==_Exmh_1308075820_2718P Content-Type: text/plain; charset=us-ascii On Sun, 12 Jun 2011 12:36:28 MDT, Jean Sacren said: > Subject: [PATCH 1/1] boot: Enhance performance by eliminating unnecessary calls to printf() > > Repeated calling to printf() for 13 times is a dire waste of CPU cycles. > For performance, combine all those calls into one while source code > formatting is preserved for readability. *facepalm* I defy anybody to find a *less* performance-critical piece of code to micro-optimize. It doesn't even make a boot faster, it makes a kernel build non-measurably faster. If you wanted to make kernel builds faster, go look at Ingo's numbers regarding the current #include mess - fixing *that* will be of more benefit than this... --==_Exmh_1308075820_2718P Content-Type: application/pgp-signature -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.4.11 (GNU/Linux) Comment: Exmh version 2.5 07/13/2001 iD8DBQFN96cscC3lWbTT17ARAnuiAKCPSWykhkJvedFKQf0po37U297MZACgreWq YhrCamM155YlqU+oX4rTEKE= =/pTQ -----END PGP SIGNATURE----- --==_Exmh_1308075820_2718P-- -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/