Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755020AbYHOLZ1 (ORCPT ); Fri, 15 Aug 2008 07:25:27 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1752877AbYHOLZS (ORCPT ); Fri, 15 Aug 2008 07:25:18 -0400 Received: from victor.provo.novell.com ([137.65.250.26]:33061 "EHLO victor.provo.novell.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752662AbYHOLZR (ORCPT ); Fri, 15 Aug 2008 07:25:17 -0400 Message-ID: <48A5670C.2080805@novell.com> Date: Fri, 15 Aug 2008 07:22:52 -0400 From: Gregory Haskins User-Agent: Thunderbird 2.0.0.16 (X11/20080720) MIME-Version: 1.0 To: Ingo Molnar CC: Steven Rostedt , linux-kernel@vger.kernel.org, Thomas Gleixner , Peter Zijlstra , Andrew Morton , Linus Torvalds , David Miller , Mathieu Desnoyers , Roland McGrath , Ulrich Drepper , Rusty Russell , Jeremy Fitzhardinge , Arnaldo Carvalho de Melo , "Luis Claudio R. Goncalves" , Clark Williams , Bruce Duncan , Marcin Slusarz , Steven Rostedt Subject: Re: [PATCH v2 0/6] ftrace: to kill a daemon (small updates) References: <20080814194506.233473381@goodmis.org> <20080815092412.GC22209@elte.hu> In-Reply-To: <20080815092412.GC22209@elte.hu> X-Enigmail-Version: 0.95.6 OpenPGP: id=D8195319 Content-Type: multipart/signed; micalg=pgp-sha1; protocol="application/pgp-signature"; boundary="------------enig6B1DA94D4FA432BA8749DD52" Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2267 Lines: 66 This is an OpenPGP/MIME signed message (RFC 2440 and 3156) --------------enig6B1DA94D4FA432BA8749DD52 Content-Type: text/plain; charset=us-ascii; format=flowed Content-Transfer-Encoding: quoted-printable (From the original mail) Steven Rostedt wrote: > > Along came Gregory Haskins, who was bickering about having ftrace enabl= ed > on a production -rt kernel. I told him the reasons that this would be b= ad > and then he started thinking out loud, and suggesting wild ideas, like > patching gcc! > =20 ^^^^^^^^^^ Ingo Molnar wrote: > Eventually gcc should be extended to provide a separate section for=20 > instrumentation patch sites, instead of us having to disassemble the=20 > object code.=20 :) I obviously agree with this, so +1 Though, tbh, at the time I suggested it I didn't think of Steve's idea=20 to post-process which was quite clever. But I do agree that having gcc=20 do it will probably save some build time since it will probably be=20 trivial for it to do this when already processing -pg. It would have the = added benefit of letting the arch specific toolchain do the arch=20 specific work (though I think Steve's solution capitalizes on the=20 toolchain extensively as it is). The biggest downside is that we would have an external dependency on gcc = for the feature, but I guess the kernel already has some of those anyway = (e.g. the stack overflow guard feature, etc). We could always fall back=20 on Steve's post-processing if the toolchain lacks the feature. -Greg --------------enig6B1DA94D4FA432BA8749DD52 Content-Type: application/pgp-signature; name="signature.asc" Content-Description: OpenPGP digital signature Content-Disposition: attachment; filename="signature.asc" -----BEGIN PGP SIGNATURE----- Version: GnuPG v2.0.9 (GNU/Linux) Comment: Using GnuPG with SUSE - http://enigmail.mozdev.org iEYEARECAAYFAkilZwwACgkQlOSOBdgZUxnNTwCfY6Foj4/ABk3NX31howqh5NoR dYAAoI0bzCYlHI8C9L8pNrnW03txphRA =1puy -----END PGP SIGNATURE----- --------------enig6B1DA94D4FA432BA8749DD52-- -- 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/