From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753630AbYKHEMw (ORCPT ); Fri, 7 Nov 2008 23:12:52 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1752384AbYKHEMn (ORCPT ); Fri, 7 Nov 2008 23:12:43 -0500 Received: from qw-out-2122.google.com ([74.125.92.26]:15378 "EHLO qw-out-2122.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752241AbYKHEMm (ORCPT ); Fri, 7 Nov 2008 23:12:42 -0500 DomainKey-Signature: a=rsa-sha1; c=nofws; d=gmail.com; s=gamma; h=message-id:date:from:to:subject:cc:in-reply-to:mime-version :content-type:content-transfer-encoding:content-disposition :references; b=YSTFlHPuN8JePkCrmPcSUp8QTpIMtvLUuCrO5Q4McMQLJVcKzYSGGpge1MzH+sCY2/ Haquhe9sUcJdiKTCFMcUHHfaLYfi4N4fWGTSkMP7GlqkODW168lQzxfEcBiroeVcegK1 k4Bikxeq5n/5O7MLuKKWtmYJoQTyEBy0/ua7U= Message-ID: Date: Sat, 8 Nov 2008 05:12:40 +0100 From: "=?ISO-8859-1?Q?Fr=E9d=E9ric_Weisbecker?=" To: "Steven Rostedt" Subject: Re: [PATCH 02/10] ftrace: fix boot trace sched startup Cc: linux-kernel@vger.kernel.org, "Ingo Molnar" , "Andrew Morton" , "Peter Zijlstra" , "Steven Rostedt" In-Reply-To: <20081108034748.991813249@goodmis.org> MIME-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Content-Disposition: inline References: <20081108034605.289816911@goodmis.org> <20081108034748.991813249@goodmis.org> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 2008/11/8 Steven Rostedt : > Impact: boot tracer startup modified > > The boot tracer calls into some of the schedule tracing private functions > that should not be exported. This patch cleans it up, and makes > way for further changes in the ftrace infrastructure. > > This patch adds a api to assign a tracer array to the schedule > context switch tracer. > > Signed-off-by: Steven Rostedt > CC: Frederic Weisbecker > --- > kernel/trace/trace.h | 2 +- > kernel/trace/trace_boot.c | 9 +++++++-- > kernel/trace/trace_sched_switch.c | 15 ++++++++++++++- > 3 files changed, 22 insertions(+), 4 deletions(-) > > diff --git a/kernel/trace/trace.h b/kernel/trace/trace.h > index 3422489..db12e16 100644 > --- a/kernel/trace/trace.h > +++ b/kernel/trace/trace.h > @@ -49,7 +49,6 @@ struct ftrace_entry { > unsigned long parent_ip; > }; > extern struct tracer boot_tracer; > -extern struct tracer sched_switch_trace; /* Used by the boot tracer */ > > /* > * Context switch trace entry - which task (and prio) we switched from/to: > @@ -325,6 +324,7 @@ void trace_function(struct trace_array *tr, > > void tracing_start_cmdline_record(void); > void tracing_stop_cmdline_record(void); > +void tracing_cmdline_assign_trace(struct trace_array *tr); > int register_tracer(struct tracer *type); > void unregister_tracer(struct tracer *type); > > diff --git a/kernel/trace/trace_boot.c b/kernel/trace/trace_boot.c > index bd5046c..662cb91 100644 > --- a/kernel/trace/trace_boot.c > +++ b/kernel/trace/trace_boot.c > @@ -39,7 +39,12 @@ void disable_boot_trace(void) > > static void reset_boot_trace(struct trace_array *tr) > { > - sched_switch_trace.reset(tr); > + int cpu; > + > + tr->time_start = ftrace_now(tr->cpu); > + > + for_each_online_cpu(cpu) > + tracing_reset(tr, cpu); > } > > static void boot_trace_init(struct trace_array *tr) > @@ -50,7 +55,7 @@ static void boot_trace_init(struct trace_array *tr) > for_each_cpu_mask(cpu, cpu_possible_map) > tracing_reset(tr, cpu); > > - sched_switch_trace.init(tr); > + tracing_cmdline_assign_trace(tr); > } > > static void boot_trace_ctrl_update(struct trace_array *tr) > diff --git a/kernel/trace/trace_sched_switch.c b/kernel/trace/trace_sched_switch.c > index 91c699b..fbf05df 100644 > --- a/kernel/trace/trace_sched_switch.c > +++ b/kernel/trace/trace_sched_switch.c > @@ -152,6 +152,19 @@ void tracing_stop_cmdline_record(void) > tracing_stop_sched_switch(); > } > > +/** > + * tracing_cmdline_assign_trace - assign a trace array for ctx switch > + * @tr: trace array pointer to assign > + * > + * Some tracers might want to record the context switches in their > + * trace. This function lets those tracers assign the trace array > + * to use. > + */ > +void tracing_cmdline_assign_trace(struct trace_array *tr) > +{ > + ctx_trace = tr; > +} > + > static void start_sched_trace(struct trace_array *tr) > { > sched_switch_reset(tr); > @@ -197,7 +210,7 @@ static void sched_switch_trace_stop(struct trace_array *tr) > tracing_stop_sched_switch(); > } > > -struct tracer sched_switch_trace __read_mostly = > +static struct tracer sched_switch_trace __read_mostly = > { > .name = "sched_switch", > .init = sched_switch_trace_init, Righ that's much proper. BTW: I see that tracing_reset is called even on start and reset callback by the tracers. Wouldn't it better to do it only on reset? Perhaps it can even be done automatically by the tracing Api itself when reset is called on every tracers. Or perhaps there could be special cases I don't see where one tracer wouldn't wish to erase is entries on reset? Acked-by: Frederic Weisbecker