[PATCH 0/2] ftrace: updates for tip

[PATCH 0/2] ftrace: updates for tip

[Steven Rostedt]

Ingo,

The following patches are in:

  git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-2.6-trace.git

    branch: tip/devel


Steven Rostedt (2):
      trace: remove internal irqsoff disabling for trace output
      trace: fix logic to start/stop counting

----
 kernel/trace/trace.c         |   13 ++++++-------
 kernel/trace/trace_irqsoff.c |   34 ++--------------------------------
 2 files changed, 8 insertions(+), 39 deletions(-)
-- 

[PATCH 1/2] trace: remove internal irqsoff disabling for trace output

[Steven Rostedt]

[-- Attachment #1: 0001-trace-remove-internal-irqsoff-disabling-for-trace-o.patch --]
[-- Type: text/plain, Size: 2990 bytes --]

From: Steven Rostedt <srostedt@redhat.com>

Impact: cleanup of duplicate features

The trace output disables the ring buffer and prevents tracing to
occur. The code in irqsoff to do the same thing is no longer needed.
This patch removes it.

Signed-off-by: Steven Rostedt <srostedt@redhat.com>
---
 kernel/trace/trace_irqsoff.c |   34 ++--------------------------------
 1 files changed, 2 insertions(+), 32 deletions(-)

diff --git a/kernel/trace/trace_irqsoff.c b/kernel/trace/trace_irqsoff.c
index 62a78d9..ed344b0 100644
--- a/kernel/trace/trace_irqsoff.c
+++ b/kernel/trace/trace_irqsoff.c
@@ -353,28 +353,18 @@ void trace_preempt_off(unsigned long a0, unsigned long a1)
 }
 #endif /* CONFIG_PREEMPT_TRACER */
 
-/*
- * save_tracer_enabled is used to save the state of the tracer_enabled
- * variable when we disable it when we open a trace output file.
- */
-static int save_tracer_enabled;
-
 static void start_irqsoff_tracer(struct trace_array *tr)
 {
 	register_ftrace_function(&trace_ops);
-	if (tracing_is_enabled()) {
+	if (tracing_is_enabled())
 		tracer_enabled = 1;
-		save_tracer_enabled = 1;
-	} else {
+	else
 		tracer_enabled = 0;
-		save_tracer_enabled = 0;
-	}
 }
 
 static void stop_irqsoff_tracer(struct trace_array *tr)
 {
 	tracer_enabled = 0;
-	save_tracer_enabled = 0;
 	unregister_ftrace_function(&trace_ops);
 }
 
@@ -395,25 +385,11 @@ static void irqsoff_tracer_reset(struct trace_array *tr)
 static void irqsoff_tracer_start(struct trace_array *tr)
 {
 	tracer_enabled = 1;
-	save_tracer_enabled = 1;
 }
 
 static void irqsoff_tracer_stop(struct trace_array *tr)
 {
 	tracer_enabled = 0;
-	save_tracer_enabled = 0;
-}
-
-static void irqsoff_tracer_open(struct trace_iterator *iter)
-{
-	/* stop the trace while dumping */
-	tracer_enabled = 0;
-}
-
-static void irqsoff_tracer_close(struct trace_iterator *iter)
-{
-	/* restart tracing */
-	tracer_enabled = save_tracer_enabled;
 }
 
 #ifdef CONFIG_IRQSOFF_TRACER
@@ -431,8 +407,6 @@ static struct tracer irqsoff_tracer __read_mostly =
 	.reset		= irqsoff_tracer_reset,
 	.start		= irqsoff_tracer_start,
 	.stop		= irqsoff_tracer_stop,
-	.open		= irqsoff_tracer_open,
-	.close		= irqsoff_tracer_close,
 	.print_max	= 1,
 #ifdef CONFIG_FTRACE_SELFTEST
 	.selftest    = trace_selftest_startup_irqsoff,
@@ -459,8 +433,6 @@ static struct tracer preemptoff_tracer __read_mostly =
 	.reset		= irqsoff_tracer_reset,
 	.start		= irqsoff_tracer_start,
 	.stop		= irqsoff_tracer_stop,
-	.open		= irqsoff_tracer_open,
-	.close		= irqsoff_tracer_close,
 	.print_max	= 1,
 #ifdef CONFIG_FTRACE_SELFTEST
 	.selftest    = trace_selftest_startup_preemptoff,
@@ -489,8 +461,6 @@ static struct tracer preemptirqsoff_tracer __read_mostly =
 	.reset		= irqsoff_tracer_reset,
 	.start		= irqsoff_tracer_start,
 	.stop		= irqsoff_tracer_stop,
-	.open		= irqsoff_tracer_open,
-	.close		= irqsoff_tracer_close,
 	.print_max	= 1,
 #ifdef CONFIG_FTRACE_SELFTEST
 	.selftest    = trace_selftest_startup_preemptirqsoff,
-- 
1.5.6.5

-- 

[PATCH 2/2] trace: fix logic to start/stop counting

[Steven Rostedt]

[-- Attachment #1: 0002-trace-fix-logic-to-start-stop-counting.patch --]
[-- Type: text/plain, Size: 916 bytes --]

From: Steven Rostedt <srostedt@redhat.com>

The logic in the tracing_start/stop code prevents the WARN_ON
from ever detecting if a start/stop pair was mismatched.

Signed-off-by: Steven Rostedt <srostedt@redhat.com>
---
 kernel/trace/trace.c |   13 ++++++-------
 1 files changed, 6 insertions(+), 7 deletions(-)

diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c
index 757ae6f..2129ab9 100644
--- a/kernel/trace/trace.c
+++ b/kernel/trace/trace.c
@@ -610,13 +610,12 @@ void tracing_start(void)
 		return;
 
 	spin_lock_irqsave(&tracing_start_lock, flags);
-	if (--trace_stop_count)
-		goto out;
-
-	if (trace_stop_count < 0) {
-		/* Someone screwed up their debugging */
-		WARN_ON_ONCE(1);
-		trace_stop_count = 0;
+	if (--trace_stop_count) {
+		if (trace_stop_count < 0) {
+			/* Someone screwed up their debugging */
+			WARN_ON_ONCE(1);
+			trace_stop_count = 0;
+		}
 		goto out;
 	}
 
-- 
1.5.6.5

-- 

Re: [PATCH 0/2] ftrace: updates for tip

[Ingo Molnar]

* Steven Rostedt <rostedt@goodmis.org> wrote:

> Ingo,
> 
> The following patches are in:
> 
>   git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-2.6-trace.git
> 
>     branch: tip/devel
> 
> 
> Steven Rostedt (2):
>       trace: remove internal irqsoff disabling for trace output
>       trace: fix logic to start/stop counting
> 
> ----
>  kernel/trace/trace.c         |   13 ++++++-------
>  kernel/trace/trace_irqsoff.c |   34 ++--------------------------------
>  2 files changed, 8 insertions(+), 39 deletions(-)

Pulled into tip/tracing/ftrace, thanks Steve!

	Ingo