[PATCH] trace event skb remove duplicate null-pointer check

[PATCH] trace event skb remove duplicate null-pointer check

[Mathieu Desnoyers]

The check for NULL skb in the kfree_skb trace event is a duplicate from the
check already done in its only caller, kfree_skb(). Remove this duplicate check.

Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Acked-by: Neil Horman <nhorman@tuxdriver.com>
CC: Steven Rostedt <rostedt@goodmis.org>
CC: Frederic Weisbecker <fweisbec@gmail.com>
CC: Ingo Molnar <mingo@elte.hu>
CC: Thomas Gleixner <tglx@linutronix.de>
CC: Zhaolei <zhaolei@cn.fujitsu.com>
---
 include/trace/events/skb.h |    4 +---
 1 file changed, 1 insertion(+), 3 deletions(-)

Index: linux-2.6-lttng/include/trace/events/skb.h
===================================================================
--- linux-2.6-lttng.orig/include/trace/events/skb.h
+++ linux-2.6-lttng/include/trace/events/skb.h
@@ -25,9 +25,7 @@ TRACE_EVENT(kfree_skb,
 
 	TP_fast_assign(
 		__entry->skbaddr = skb;
-		if (skb) {
-			__entry->protocol = ntohs(skb->protocol);
-		}
+		__entry->protocol = ntohs(skb->protocol);
 		__entry->location = location;
 	),
 

-- 
Mathieu Desnoyers
Operating System Efficiency R&D Consultant
EfficiOS Inc.
http://www.efficios.com

Re: [PATCH] trace event skb remove duplicate null-pointer check

[David Miller]

From: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Date: Thu, 6 Jan 2011 12:53:19 -0500

> The check for NULL skb in the kfree_skb trace event is a duplicate from the
> check already done in its only caller, kfree_skb(). Remove this duplicate check.
> 
> Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
> Acked-by: Neil Horman <nhorman@tuxdriver.com>

Acked-by: David S. Miller <davem@davemloft.net>

Re: [PATCH] trace event skb remove duplicate null-pointer check

[Frederic Weisbecker]

On Thu, Jan 06, 2011 at 10:15:44AM -0800, David Miller wrote:
> From: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
> Date: Thu, 6 Jan 2011 12:53:19 -0500
> 
> > The check for NULL skb in the kfree_skb trace event is a duplicate from the
> > check already done in its only caller, kfree_skb(). Remove this duplicate check.
> > 
> > Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
> > Acked-by: Neil Horman <nhorman@tuxdriver.com>
> 
> Acked-by: David S. Miller <davem@davemloft.net>

May be you want to take that on the net tree? Looks like more appropriate.
Of course this can go through the tracing tree as well.

Thanks.

Re: [PATCH] trace event skb remove duplicate null-pointer check

[David Miller]

From: Frederic Weisbecker <fweisbec@gmail.com>
Date: Thu, 6 Jan 2011 19:17:29 +0100

> On Thu, Jan 06, 2011 at 10:15:44AM -0800, David Miller wrote:
>> From: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
>> Date: Thu, 6 Jan 2011 12:53:19 -0500
>> 
>> > The check for NULL skb in the kfree_skb trace event is a duplicate from the
>> > check already done in its only caller, kfree_skb(). Remove this duplicate check.
>> > 
>> > Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
>> > Acked-by: Neil Horman <nhorman@tuxdriver.com>
>> 
>> Acked-by: David S. Miller <davem@davemloft.net>
> 
> May be you want to take that on the net tree? Looks like more appropriate.
> Of course this can go through the tracing tree as well.

You guys can take it in the tracing tree, this actually makes things
easier for me.

Re: [PATCH] trace event skb remove duplicate null-pointer check

[Mathieu Desnoyers]

* Frederic Weisbecker (fweisbec@gmail.com) wrote:
> On Thu, Jan 06, 2011 at 10:15:44AM -0800, David Miller wrote:
> > From: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
> > Date: Thu, 6 Jan 2011 12:53:19 -0500
> > 
> > > The check for NULL skb in the kfree_skb trace event is a duplicate from the
> > > check already done in its only caller, kfree_skb(). Remove this duplicate check.
> > > 
> > > Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
> > > Acked-by: Neil Horman <nhorman@tuxdriver.com>
> > 
> > Acked-by: David S. Miller <davem@davemloft.net>
> 
> May be you want to take that on the net tree? Looks like more appropriate.
> Of course this can go through the tracing tree as well.

It might be easier to manage the TRACE_EVENT() reshaping (removal of semicolumn,
tp_assign, etc) I am preparing if, at this stage, we merge most of the
include/trace/event patches through a single tree (the tracing tree). Otherwise
we might end up with more commit cross-dependencies between the trees, and
increase the risk of conflicts.

Thanks,

Mathieu

> 
> Thanks.

-- 
Mathieu Desnoyers
Operating System Efficiency R&D Consultant
EfficiOS Inc.
http://www.efficios.com

Re: [PATCH] trace event skb remove duplicate null-pointer check

[Frederic Weisbecker]

On Thu, Jan 06, 2011 at 01:38:02PM -0500, Mathieu Desnoyers wrote:
> * Frederic Weisbecker (fweisbec@gmail.com) wrote:
> > On Thu, Jan 06, 2011 at 10:15:44AM -0800, David Miller wrote:
> > > From: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
> > > Date: Thu, 6 Jan 2011 12:53:19 -0500
> > > 
> > > > The check for NULL skb in the kfree_skb trace event is a duplicate from the
> > > > check already done in its only caller, kfree_skb(). Remove this duplicate check.
> > > > 
> > > > Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
> > > > Acked-by: Neil Horman <nhorman@tuxdriver.com>
> > > 
> > > Acked-by: David S. Miller <davem@davemloft.net>
> > 
> > May be you want to take that on the net tree? Looks like more appropriate.
> > Of course this can go through the tracing tree as well.
> 
> It might be easier to manage the TRACE_EVENT() reshaping (removal of semicolumn,
> tp_assign, etc) I am preparing if, at this stage, we merge most of the
> include/trace/event patches through a single tree (the tracing tree). Otherwise
> we might end up with more commit cross-dependencies between the trees, and
> increase the risk of conflicts.

Alright, let's take that on the tracing tree.

I'll apply them if Steve doesn't beat me at it.

Thanks.

[tip:perf/urgent] tracing: remove duplicate null-pointer check in skb tracepoint

[tip-bot for Mathieu Desnoyers]

Commit-ID:  881fe4bdcdc899674524e30a76c76d298b447008
Gitweb:     http://git.kernel.org/tip/881fe4bdcdc899674524e30a76c76d298b447008
Author:     Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
AuthorDate: Thu, 6 Jan 2011 12:53:19 -0500
Committer:  Steven Rostedt <rostedt@goodmis.org>
CommitDate: Fri, 7 Jan 2011 20:55:42 -0500

tracing: remove duplicate null-pointer check in skb tracepoint

The check for NULL skb in the kfree_skb trace event is a duplicate from the
check already done in its only caller, kfree_skb(). Remove this duplicate check.

Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
LKML-Reference: <20110106175319.GA30610@Krystal>
Acked-by: Neil Horman <nhorman@tuxdriver.com>
Acked-by: David S. Miller <davem@davemloft.net>
CC: Steven Rostedt <rostedt@goodmis.org>
CC: Frederic Weisbecker <fweisbec@gmail.com>
CC: Ingo Molnar <mingo@elte.hu>
CC: Thomas Gleixner <tglx@linutronix.de>
CC: Zhaolei <zhaolei@cn.fujitsu.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
---
 include/trace/events/skb.h |    4 +---
 1 files changed, 1 insertions(+), 3 deletions(-)

diff --git a/include/trace/events/skb.h b/include/trace/events/skb.h
index 75ce9d5..f10293c 100644
--- a/include/trace/events/skb.h
+++ b/include/trace/events/skb.h
@@ -25,9 +25,7 @@ TRACE_EVENT(kfree_skb,
 
 	TP_fast_assign(
 		__entry->skbaddr = skb;
-		if (skb) {
-			__entry->protocol = ntohs(skb->protocol);
-		}
+		__entry->protocol = ntohs(skb->protocol);
 		__entry->location = location;
 	),