Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1757516AbZCLXt5 (ORCPT ); Thu, 12 Mar 2009 19:49:57 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1756400AbZCLXtk (ORCPT ); Thu, 12 Mar 2009 19:49:40 -0400 Received: from mx3.mail.elte.hu ([157.181.1.138]:36878 "EHLO mx3.mail.elte.hu" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753954AbZCLXtj (ORCPT ); Thu, 12 Mar 2009 19:49:39 -0400 Date: Fri, 13 Mar 2009 00:49:12 +0100 From: Ingo Molnar To: Frederic Weisbecker Cc: Jason Baron , rostedt@goodmis.org, linux-kernel@vger.kernel.org, acme@ghostprotocols.net, fche@redhat.com, peterz@infradead.org, compudj@krystal.dyndns.org Subject: Re: [Patch 2/2] tracepoints for softirq entry/exit - tracepoints Message-ID: <20090312234912.GA3381@elte.hu> References: <20090312183603.GC3352@redhat.com> <20090312190243.GC11045@nowhere> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20090312190243.GC11045@nowhere> 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 Content-Length: 2701 Lines: 92 * Frederic Weisbecker wrote: > On Thu, Mar 12, 2009 at 02:36:03PM -0400, Jason Baron wrote: > > > > introduce softirq entry/exit tracepoints. These are useful for > > augmenting existing tracers, and to figure out softirq frequencies and > > timings. > > > > Signed-off-by: Jason Baron > > > > --- > > > > include/trace/irq_event_types.h | 12 ++++++++++++ > > kernel/softirq.c | 7 ++++++- > > 2 files changed, 18 insertions(+), 1 deletions(-) > > > > > > diff --git a/include/trace/irq_event_types.h b/include/trace/irq_event_types.h > > index 214bb92..38b4bdd 100644 > > --- a/include/trace/irq_event_types.h > > +++ b/include/trace/irq_event_types.h > > @@ -40,4 +40,16 @@ TRACE_EVENT(irq_handler_exit, > > __entry->irq, __entry->ret ? "handled" : "unhandled") > > ); > > > > +TRACE_FORMAT(irq_softirq_entry, > > + TP_PROTO(struct softirq_action *h, struct softirq_action *vec), > > + TP_ARGS(h, vec), > > + TP_FMT("softirq=%d action=%s", h - vec, softirq_to_name[h-vec]) > > + ); > > + > > +TRACE_FORMAT(irq_softirq_exit, > > + TP_PROTO(struct softirq_action *h, struct softirq_action *vec), > > + TP_ARGS(h, vec), > > + TP_FMT("softirq=%d action=%s", h - vec, softirq_to_name[h-vec]) > > + ); > > + > > #undef TRACE_SYSTEM > > diff --git a/kernel/softirq.c b/kernel/softirq.c > > index ba1511f..c378d53 100644 > > --- a/kernel/softirq.c > > +++ b/kernel/softirq.c > > @@ -24,6 +24,7 @@ > > #include > > #include > > #include > > +#include > > > > #include > > /* > > @@ -186,6 +187,9 @@ EXPORT_SYMBOL(local_bh_enable_ip); > > */ > > #define MAX_SOFTIRQ_RESTART 10 > > > > +DEFINE_TRACE(irq_softirq_entry); > > +DEFINE_TRACE(irq_softirq_exit); > > > Just one nit here. The "irq_" prefix seems to me too much. > On the trace we have: > > /* irq_softirq_entry: softirq=nb action=nb_to_logical_name */ > > It's even too much words that says the same things. > Moreover, we have the logical name, the number seems not very useful > because we have its logical translation just after. > > I would suggest to have just: > > /* softirq_entry: nb_to_logical_name */ > > ie: > > /* softirq_entry: SCHED_SOFTIRQ */ > > Don't you think it's more clear and obvious? yeah. > Other than that, I think these tracepoints are a good idea. agreed. Acked-by: Ingo Molnar Ingo -- 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/