From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754135AbZBIL6x (ORCPT ); Mon, 9 Feb 2009 06:58:53 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1754897AbZBIL6m (ORCPT ); Mon, 9 Feb 2009 06:58:42 -0500 Received: from mx2.mail.elte.hu ([157.181.151.9]:41807 "EHLO mx2.mail.elte.hu" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753065AbZBIL6l (ORCPT ); Mon, 9 Feb 2009 06:58:41 -0500 Date: Mon, 9 Feb 2009 12:58:25 +0100 From: Ingo Molnar To: Arnaldo Carvalho de Melo Cc: Steven Rostedt , Linux Kernel Mailing List Subject: Re: [PATCH tip 1/1] tracing: handle unregistering the current tracer Message-ID: <20090209115825.GA17782@elte.hu> References: <20090207205259.GB11892@ghostprotocols.net> <20090209095816.GB20467@elte.hu> <20090209115151.GB5265@ghostprotocols.net> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20090209115151.GB5265@ghostprotocols.net> User-Agent: Mutt/1.5.18 (2008-05-17) X-ELTE-VirusStatus: clean X-ELTE-SpamScore: -1.5 X-ELTE-SpamLevel: X-ELTE-SpamCheck: no X-ELTE-SpamVersion: ELTE 2.0 X-ELTE-SpamCheck-Details: score=-1.5 required=5.9 tests=BAYES_00 autolearn=no SpamAssassin version=3.2.3 -1.5 BAYES_00 BODY: Bayesian spam probability is 0 to 1% [score: 0.0000] Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org * Arnaldo Carvalho de Melo wrote: > Em Mon, Feb 09, 2009 at 10:58:16AM +0100, Ingo Molnar escreveu: > > > > * Arnaldo Carvalho de Melo wrote: > > > > > Impact: simplification > > > > > > Instead of requiring that plugins have the sequence: > > > > > > my_tracer_stop(my_trace_array); > > > unregister_tracer(my_tracer); > > > > > > it should be possible just do a: > > > > > > unregister_tracer(my_tracer); > > > > > > Signed-off-by: Arnaldo Carvalho de Melo > > > --- > > > kernel/trace/trace.c | 9 +++++++++ > > > 1 files changed, 9 insertions(+), 0 deletions(-) > > > > Applied to tip/tracing/ftrace, thanks Arnaldo! > > > > Nice one - we should try to shoot for the smallest physically > > possible linecount for any new (possibly trivial) tracer plugin. > > That and also for as few as possible EXPORT_SYMBOL_GPL entries, now, for > converting net/ipv4/tcp_probe.c to an ftrace plugin + one tracepoint at > tcp_rcv_established we need: > > doppio linux-2.6-tip]$ grep ^+EXPORT_SYMBOL ~/tcp_cwnd_tracer.patch > +EXPORT_SYMBOL_GPL(register_tracer); > +EXPORT_SYMBOL_GPL(unregister_tracer); > +EXPORT_SYMBOL_GPL(tracing_record_cmdline); > +EXPORT_SYMBOL_GPL(trace_buffer_lock_reserve); > +EXPORT_SYMBOL_GPL(trace_buffer_unlock_commit); > +EXPORT_SYMBOL_GPL(trace_seq_printf); > +EXPORT_SYMBOL_GPL(register_ftrace_event); > +EXPORT_SYMBOL_GPL(unregister_ftrace_event); > [acme@doppio linux-2.6-tip]$ ok. For in-kernel plugins it's of course fine to do those exports in any case. Ingo