Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1760091AbZDQQK1 (ORCPT ); Fri, 17 Apr 2009 12:10:27 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1759587AbZDQQKM (ORCPT ); Fri, 17 Apr 2009 12:10:12 -0400 Received: from tomts20.bellnexxia.net ([209.226.175.74]:39844 "EHLO tomts20-srv.bellnexxia.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1758974AbZDQQKL (ORCPT ); Fri, 17 Apr 2009 12:10:11 -0400 X-IronPort-Anti-Spam-Filtered: true X-IronPort-Anti-Spam-Result: Au4EAG9D6ElMQW1W/2dsb2JhbACBTs5Ag30G Date: Fri, 17 Apr 2009 12:10:05 -0400 From: Mathieu Desnoyers To: Ingo Molnar Cc: Jeremy Fitzhardinge , Steven Rostedt , Linux Kernel Mailing List , Jeremy Fitzhardinge Subject: Re: [PATCH 1/4] tracing: move __DO_TRACE out of line Message-ID: <20090417161005.GA16361@Krystal> References: <1239950139-1119-1-git-send-email-jeremy@goop.org> <1239950139-1119-2-git-send-email-jeremy@goop.org> <20090417154640.GB8253@elte.hu> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit Content-Disposition: inline In-Reply-To: <20090417154640.GB8253@elte.hu> X-Editor: vi X-Info: http://krystal.dyndns.org:8080 X-Operating-System: Linux/2.6.21.3-grsec (i686) X-Uptime: 12:06:49 up 48 days, 12:33, 3 users, load average: 1.20, 0.78, 0.79 User-Agent: Mutt/1.5.18 (2008-05-17) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1587 Lines: 50 * Ingo Molnar (mingo@elte.hu) wrote: > > * Jeremy Fitzhardinge wrote: > > > From: Jeremy Fitzhardinge > > > > Mainly simplify linux/tracepoint.h's include dependencies (removes > > rcupdate.h), but it can't help with icache locality, since it > > definitely moves the code out of line, rather than relying on gcc > > to do it. > > > --- a/include/linux/tracepoint.h > > +++ b/include/linux/tracepoint.h > > @@ -15,7 +15,6 @@ > > */ > > > > #include > > -#include > > nice! > > > +#define DEFINE_DO_TRACE(name, proto, args) \ > > + void __do_trace_##name(struct tracepoint *tp, TP_PROTO(proto)) \ > > + { \ > > that needs to be marked notrace, otherwise the function tracer > becomes noisy. (or even lockupy.) > I guess I'll have to put it more clearly : I am all for minimizing tracepoint header dependency, but I'll be nacking this kind of out-of-lining patch. Taking a function call, and moving it out-of-line (thus duplicating the function call for nothing) seems *really* pointless and will hurt tracer performance. If thread_info.h is now so big that it needs a cleanup, I guess we'll just have to do it. Mathieu > Ingo -- Mathieu Desnoyers OpenPGP key fingerprint: 8CD5 52C3 8E3C 4140 715F BA06 3F25 A8FE 3BAE 9A68 -- 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/