From 5361499101306cfb776c3cfa0f69d0479bc63868 Mon Sep 17 00:00:00 2001
From: Steven Rostedt <srostedt@redhat.com>
Date: Thu, 15 Jan 2009 19:12:40 -0500
Subject: ftrace: add stack trace to function tracer

Impact: new feature to stack trace any function

Chris Mason asked about being able to pick and choose a function
and get a stack trace from it. This feature enables his request.

 # echo io_schedule > /debug/tracing/set_ftrace_filter
 # echo function > /debug/tracing/current_tracer
 # echo func_stack_trace > /debug/tracing/trace_options

Produces the following in /debug/tracing/trace:

       kjournald-702   [001]   135.673060: io_schedule <-sync_buffer
       kjournald-702   [002]   135.673671:
 <= sync_buffer
 <= __wait_on_bit
 <= out_of_line_wait_on_bit
 <= __wait_on_buffer
 <= sync_dirty_buffer
 <= journal_commit_transaction
 <= kjournald

Note, be careful about turning this on without filtering the functions.
You may find that you have a 10 second lag between typing and seeing
what you typed. This is why the stack trace for the function tracer
does not use the same stack_trace flag as the other tracers use.

Signed-off-by: Steven Rostedt <srostedt@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
---
 kernel/trace/trace_functions.c | 84 ++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 84 insertions(+)

(limited to 'kernel/trace/trace_functions.c')

diff --git a/kernel/trace/trace_functions.c b/kernel/trace/trace_functions.c
index 9236d7e25a16..3a5fa08cedb0 100644
--- a/kernel/trace/trace_functions.c
+++ b/kernel/trace/trace_functions.c
@@ -16,6 +16,8 @@
 
 #include "trace.h"
 
+static struct trace_array	*func_trace;
+
 static void start_function_trace(struct trace_array *tr)
 {
 	tr->cpu = get_cpu();
@@ -34,6 +36,7 @@ static void stop_function_trace(struct trace_array *tr)
 
 static int function_trace_init(struct trace_array *tr)
 {
+	func_trace = tr;
 	start_function_trace(tr);
 	return 0;
 }
@@ -48,12 +51,93 @@ static void function_trace_start(struct trace_array *tr)
 	tracing_reset_online_cpus(tr);
 }
 
+static void
+function_stack_trace_call(unsigned long ip, unsigned long parent_ip)
+{
+	struct trace_array *tr = func_trace;
+	struct trace_array_cpu *data;
+	unsigned long flags;
+	long disabled;
+	int cpu;
+	int pc;
+
+	if (unlikely(!ftrace_function_enabled))
+		return;
+
+	/*
+	 * Need to use raw, since this must be called before the
+	 * recursive protection is performed.
+	 */
+	local_irq_save(flags);
+	cpu = raw_smp_processor_id();
+	data = tr->data[cpu];
+	disabled = atomic_inc_return(&data->disabled);
+
+	if (likely(disabled == 1)) {
+		pc = preempt_count();
+		/*
+		 * skip over 5 funcs:
+		 *    __ftrace_trace_stack,
+		 *    __trace_stack,
+		 *    function_stack_trace_call
+		 *    ftrace_list_func
+		 *    ftrace_call
+		 */
+		__trace_stack(tr, data, flags, 5, pc);
+	}
+
+	atomic_dec(&data->disabled);
+	local_irq_restore(flags);
+}
+
+static struct ftrace_ops trace_stack_ops __read_mostly =
+{
+	.func = function_stack_trace_call,
+};
+
+/* Our two options */
+enum {
+	TRACE_FUNC_OPT_STACK = 0x1,
+};
+
+static struct tracer_opt func_opts[] = {
+#ifdef CONFIG_STACKTRACE
+	{ TRACER_OPT(func_stack_trace, TRACE_FUNC_OPT_STACK) },
+#endif
+	{ } /* Always set a last empty entry */
+};
+
+static struct tracer_flags func_flags = {
+	.val = 0, /* By default: all flags disabled */
+	.opts = func_opts
+};
+
+static int func_set_flag(u32 old_flags, u32 bit, int set)
+{
+	if (bit == TRACE_FUNC_OPT_STACK) {
+		/* do nothing if already set */
+		if (!!set == !!(func_flags.val & TRACE_FUNC_OPT_STACK))
+			return 0;
+
+		if (set)
+			register_ftrace_function(&trace_stack_ops);
+		else
+			unregister_ftrace_function(&trace_stack_ops);
+
+		return 0;
+	}
+
+	return -EINVAL;
+}
+
 static struct tracer function_trace __read_mostly =
 {
 	.name	     = "function",
 	.init	     = function_trace_init,
 	.reset	     = function_trace_reset,
 	.start	     = function_trace_start,
+	.flags		= &func_flags,
+	.set_flag	= func_set_flag,
 #ifdef CONFIG_FTRACE_SELFTEST
 	.selftest    = trace_selftest_startup_function,
 #endif
-- 
cgit v1.2.3


From bb3c3c95f330f7bf16e33b002e48882616089db1 Mon Sep 17 00:00:00 2001
From: Steven Rostedt <srostedt@redhat.com>
Date: Thu, 15 Jan 2009 20:40:23 -0500
Subject: ftrace: move function tracer functions out of trace.c

Impact: clean up of trace.c

The function tracer functions were put in trace.c because it needed
to share static variables that were in trace.c.  Since then, those
variables have become global for various reasons. This patch moves
the function tracer functions into trace_function.c where they belong.

Signed-off-by: Steven Rostedt <srostedt@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
---
 kernel/trace/trace.c           | 84 ------------------------------------------
 kernel/trace/trace_functions.c | 84 +++++++++++++++++++++++++++++++++++++++++-
 2 files changed, 83 insertions(+), 85 deletions(-)

(limited to 'kernel/trace/trace_functions.c')

diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c
index 3c54cb125228..2585ffb6c6b5 100644
--- a/kernel/trace/trace.c
+++ b/kernel/trace/trace.c
@@ -1046,65 +1046,6 @@ ftrace_special(unsigned long arg1, unsigned long arg2, unsigned long arg3)
 	local_irq_restore(flags);
 }
 
-#ifdef CONFIG_FUNCTION_TRACER
-static void
-function_trace_call_preempt_only(unsigned long ip, unsigned long parent_ip)
-{
-	struct trace_array *tr = &global_trace;
-	struct trace_array_cpu *data;
-	unsigned long flags;
-	long disabled;
-	int cpu, resched;
-	int pc;
-
-	if (unlikely(!ftrace_function_enabled))
-		return;
-
-	pc = preempt_count();
-	resched = ftrace_preempt_disable();
-	local_save_flags(flags);
-	cpu = raw_smp_processor_id();
-	data = tr->data[cpu];
-	disabled = atomic_inc_return(&data->disabled);
-
-	if (likely(disabled == 1))
-		trace_function(tr, data, ip, parent_ip, flags, pc);
-
-	atomic_dec(&data->disabled);
-	ftrace_preempt_enable(resched);
-}
-
-static void
-function_trace_call(unsigned long ip, unsigned long parent_ip)
-{
-	struct trace_array *tr = &global_trace;
-	struct trace_array_cpu *data;
-	unsigned long flags;
-	long disabled;
-	int cpu;
-	int pc;
-
-	if (unlikely(!ftrace_function_enabled))
-		return;
-
-	/*
-	 * Need to use raw, since this must be called before the
-	 * recursive protection is performed.
-	 */
-	local_irq_save(flags);
-	cpu = raw_smp_processor_id();
-	data = tr->data[cpu];
-	disabled = atomic_inc_return(&data->disabled);
-
-	if (likely(disabled == 1)) {
-		pc = preempt_count();
-		trace_function(tr, data, ip, parent_ip, flags, pc);
-	}
-
-	atomic_dec(&data->disabled);
-	local_irq_restore(flags);
-}
-
 #ifdef CONFIG_FUNCTION_GRAPH_TRACER
 int trace_graph_entry(struct ftrace_graph_ent *trace)
 {
@@ -1162,31 +1103,6 @@ void trace_graph_return(struct ftrace_graph_ret *trace)
 }
 #endif /* CONFIG_FUNCTION_GRAPH_TRACER */
 
-static struct ftrace_ops trace_ops __read_mostly =
-{
-	.func = function_trace_call,
-};
-
-void tracing_start_function_trace(void)
-{
-	ftrace_function_enabled = 0;
-
-	if (trace_flags & TRACE_ITER_PREEMPTONLY)
-		trace_ops.func = function_trace_call_preempt_only;
-	else
-		trace_ops.func = function_trace_call;
-
-	register_ftrace_function(&trace_ops);
-	ftrace_function_enabled = 1;
-}
-
-void tracing_stop_function_trace(void)
-{
-	ftrace_function_enabled = 0;
-	unregister_ftrace_function(&trace_ops);
-}
-#endif
-
 enum trace_file_type {
 	TRACE_FILE_LAT_FMT	= 1,
 	TRACE_FILE_ANNOTATE	= 2,
diff --git a/kernel/trace/trace_functions.c b/kernel/trace/trace_functions.c
index 3a5fa08cedb0..2dce3c7370d1 100644
--- a/kernel/trace/trace_functions.c
+++ b/kernel/trace/trace_functions.c
@@ -20,6 +20,7 @@ static struct trace_array	*func_trace;
 
 static void start_function_trace(struct trace_array *tr)
 {
+	func_trace = tr;
 	tr->cpu = get_cpu();
 	tracing_reset_online_cpus(tr);
 	put_cpu();
@@ -36,7 +37,6 @@ static void stop_function_trace(struct trace_array *tr)
 
 static int function_trace_init(struct trace_array *tr)
 {
-	func_trace = tr;
 	start_function_trace(tr);
 	return 0;
 }
@@ -51,6 +51,64 @@ static void function_trace_start(struct trace_array *tr)
 	tracing_reset_online_cpus(tr);
 }
 
+static void
+function_trace_call_preempt_only(unsigned long ip, unsigned long parent_ip)
+{
+	struct trace_array *tr = func_trace;
+	struct trace_array_cpu *data;
+	unsigned long flags;
+	long disabled;
+	int cpu, resched;
+	int pc;
+
+	if (unlikely(!ftrace_function_enabled))
+		return;
+
+	pc = preempt_count();
+	resched = ftrace_preempt_disable();
+	local_save_flags(flags);
+	cpu = raw_smp_processor_id();
+	data = tr->data[cpu];
+	disabled = atomic_inc_return(&data->disabled);
+
+	if (likely(disabled == 1))
+		trace_function(tr, data, ip, parent_ip, flags, pc);
+
+	atomic_dec(&data->disabled);
+	ftrace_preempt_enable(resched);
+}
+
+static void
+function_trace_call(unsigned long ip, unsigned long parent_ip)
+{
+	struct trace_array *tr = func_trace;
+	struct trace_array_cpu *data;
+	unsigned long flags;
+	long disabled;
+	int cpu;
+	int pc;
+
+	if (unlikely(!ftrace_function_enabled))
+		return;
+
+	/*
+	 * Need to use raw, since this must be called before the
+	 * recursive protection is performed.
+	 */
+	local_irq_save(flags);
+	cpu = raw_smp_processor_id();
+	data = tr->data[cpu];
+	disabled = atomic_inc_return(&data->disabled);
+
+	if (likely(disabled == 1)) {
+		pc = preempt_count();
+		trace_function(tr, data, ip, parent_ip, flags, pc);
+	}
+
+	atomic_dec(&data->disabled);
+	local_irq_restore(flags);
+}
+
 static void
 function_stack_trace_call(unsigned long ip, unsigned long parent_ip)
 {
@@ -90,6 +148,30 @@ function_stack_trace_call(unsigned long ip, unsigned long parent_ip)
 	local_irq_restore(flags);
 }
 
+
+static struct ftrace_ops trace_ops __read_mostly =
+{
+	.func = function_trace_call,
+};
+
+void tracing_start_function_trace(void)
+{
+	ftrace_function_enabled = 0;
+
+	if (trace_flags & TRACE_ITER_PREEMPTONLY)
+		trace_ops.func = function_trace_call_preempt_only;
+	else
+		trace_ops.func = function_trace_call;
+
+	register_ftrace_function(&trace_ops);
+	ftrace_function_enabled = 1;
+}
+
+void tracing_stop_function_trace(void)
+{
+	ftrace_function_enabled = 0;
+	unregister_ftrace_function(&trace_ops);
+}
 static struct ftrace_ops trace_stack_ops __read_mostly =
 {
 	.func = function_stack_trace_call,
-- 
cgit v1.2.3


From 3eb36aa05329a47cbe201c151fd0024a4a3649cd Mon Sep 17 00:00:00 2001
From: Steven Rostedt <srostedt@redhat.com>
Date: Thu, 15 Jan 2009 22:21:43 -0500
Subject: ftrace: combine stack trace in function call

Impact: less likely to interleave function and stack traces

This patch does replaces the separate stack trace on function with
a record function and stack trace together. This will switch between
the function only recording to a function and stack recording.

Also some whitespace fix ups as well.

Signed-off-by: Steven Rostedt <srostedt@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
---
 kernel/trace/trace_functions.c | 61 +++++++++++++++++++++++++-----------------
 1 file changed, 36 insertions(+), 25 deletions(-)

(limited to 'kernel/trace/trace_functions.c')

diff --git a/kernel/trace/trace_functions.c b/kernel/trace/trace_functions.c
index 2dce3c7370d1..61d0b73dabf5 100644
--- a/kernel/trace/trace_functions.c
+++ b/kernel/trace/trace_functions.c
@@ -133,6 +133,7 @@ function_stack_trace_call(unsigned long ip, unsigned long parent_ip)
 
 	if (likely(disabled == 1)) {
 		pc = preempt_count();
+		trace_function(tr, data, ip, parent_ip, flags, pc);
 		/*
 		 * skip over 5 funcs:
 		 *    __ftrace_trace_stack,
@@ -154,24 +155,6 @@ static struct ftrace_ops trace_ops __read_mostly =
 	.func = function_trace_call,
 };
 
-void tracing_start_function_trace(void)
-{
-	ftrace_function_enabled = 0;
-
-	if (trace_flags & TRACE_ITER_PREEMPTONLY)
-		trace_ops.func = function_trace_call_preempt_only;
-	else
-		trace_ops.func = function_trace_call;
-
-	register_ftrace_function(&trace_ops);
-	ftrace_function_enabled = 1;
-}
-
-void tracing_stop_function_trace(void)
-{
-	ftrace_function_enabled = 0;
-	unregister_ftrace_function(&trace_ops);
-}
 static struct ftrace_ops trace_stack_ops __read_mostly =
 {
 	.func = function_stack_trace_call,
@@ -194,6 +177,31 @@ static struct tracer_flags func_flags = {
 	.opts = func_opts
 };
 
+void tracing_start_function_trace(void)
+{
+	ftrace_function_enabled = 0;
+
+	if (trace_flags & TRACE_ITER_PREEMPTONLY)
+		trace_ops.func = function_trace_call_preempt_only;
+	else
+		trace_ops.func = function_trace_call;
+
+	if (func_flags.val & TRACE_FUNC_OPT_STACK)
+		register_ftrace_function(&trace_stack_ops);
+	else
+		register_ftrace_function(&trace_ops);
+
+	ftrace_function_enabled = 1;
+}
+
+void tracing_stop_function_trace(void)
+{
+	ftrace_function_enabled = 0;
+	/* OK if they are not registered */
+	unregister_ftrace_function(&trace_stack_ops);
+	unregister_ftrace_function(&trace_ops);
+}
+
 static int func_set_flag(u32 old_flags, u32 bit, int set)
 {
 	if (bit == TRACE_FUNC_OPT_STACK) {
@@ -201,10 +209,13 @@ static int func_set_flag(u32 old_flags, u32 bit, int set)
 		if (!!set == !!(func_flags.val & TRACE_FUNC_OPT_STACK))
 			return 0;
 
-		if (set)
+		if (set) {
+			unregister_ftrace_function(&trace_ops);
 			register_ftrace_function(&trace_stack_ops);
-		else
+		} else {
 			unregister_ftrace_function(&trace_stack_ops);
+			register_ftrace_function(&trace_ops);
+		}
 
 		return 0;
 	}
@@ -214,14 +225,14 @@ static int func_set_flag(u32 old_flags, u32 bit, int set)
 
 static struct tracer function_trace __read_mostly =
 {
-	.name	     = "function",
-	.init	     = function_trace_init,
-	.reset	     = function_trace_reset,
-	.start	     = function_trace_start,
+	.name		= "function",
+	.init		= function_trace_init,
+	.reset		= function_trace_reset,
+	.start		= function_trace_start,
 	.flags		= &func_flags,
 	.set_flag	= func_set_flag,
 #ifdef CONFIG_FTRACE_SELFTEST
-	.selftest    = trace_selftest_startup_function,
+	.selftest	= trace_selftest_startup_function,
 #endif
 };
 
-- 
cgit v1.2.3


From a225cdd263f340c864febb1992802fb5b08bc328 Mon Sep 17 00:00:00 2001
From: Steven Rostedt <srostedt@redhat.com>
Date: Thu, 15 Jan 2009 23:06:03 -0500
Subject: ftrace: remove static from function tracer functions

Impact: clean up

After reorganizing the functions in trace.c and trace_function.c,
they no longer need to be in global context. This patch makes the
functions and one variable into static.

Signed-off-by: Steven Rostedt <srostedt@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
---
 kernel/trace/trace.c           |  3 ---
 kernel/trace/trace.h           | 10 ----------
 kernel/trace/trace_functions.c | 10 ++++++++--
 3 files changed, 8 insertions(+), 15 deletions(-)

(limited to 'kernel/trace/trace_functions.c')

diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c
index 2585ffb6c6b5..7de6a94063dd 100644
--- a/kernel/trace/trace.c
+++ b/kernel/trace/trace.c
@@ -187,9 +187,6 @@ int tracing_is_enabled(void)
 	return tracer_enabled;
 }
 
-/* function tracing enabled */
-int				ftrace_function_enabled;
-
 /*
  * trace_buf_size is the size in bytes that is allocated
  * for a buffer. Note, the number of bytes is always rounded
diff --git a/kernel/trace/trace.h b/kernel/trace/trace.h
index bf39a369e4b3..54b72781e920 100644
--- a/kernel/trace/trace.h
+++ b/kernel/trace/trace.h
@@ -464,16 +464,6 @@ void __trace_stack(struct trace_array *tr,
 
 extern cycle_t ftrace_now(int cpu);
 
-#ifdef CONFIG_FUNCTION_TRACER
-void tracing_start_function_trace(void);
-void tracing_stop_function_trace(void);
-#else
-# define tracing_start_function_trace()		do { } while (0)
-# define tracing_stop_function_trace()		do { } while (0)
-#endif
-
-extern int ftrace_function_enabled;
-
 #ifdef CONFIG_CONTEXT_SWITCH_TRACER
 typedef void
 (*tracer_switch_func_t)(void *private,
diff --git a/kernel/trace/trace_functions.c b/kernel/trace/trace_functions.c
index 61d0b73dabf5..b3a320f8aba7 100644
--- a/kernel/trace/trace_functions.c
+++ b/kernel/trace/trace_functions.c
@@ -16,8 +16,14 @@
 
 #include "trace.h"
 
+/* function tracing enabled */
+static int			ftrace_function_enabled;
+
 static struct trace_array	*func_trace;
 
+static void tracing_start_function_trace(void);
+static void tracing_stop_function_trace(void);
+
 static void start_function_trace(struct trace_array *tr)
 {
 	func_trace = tr;
@@ -177,7 +183,7 @@ static struct tracer_flags func_flags = {
 	.opts = func_opts
 };
 
-void tracing_start_function_trace(void)
+static void tracing_start_function_trace(void)
 {
 	ftrace_function_enabled = 0;
 
@@ -194,7 +200,7 @@ void tracing_start_function_trace(void)
 	ftrace_function_enabled = 1;
 }
 
-void tracing_stop_function_trace(void)
+static void tracing_stop_function_trace(void)
 {
 	ftrace_function_enabled = 0;
 	/* OK if they are not registered */
-- 
cgit v1.2.3


From 7be421510b91491d5aa5a29fa1005712039b95af Mon Sep 17 00:00:00 2001
From: Arnaldo Carvalho de Melo <acme@redhat.com>
Date: Thu, 5 Feb 2009 01:13:37 -0500
Subject: trace: Remove unused trace_array_cpu parameter

Impact: cleanup

Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: Steven Rostedt <srostedt@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
---
 block/blktrace.c                  |  2 +-
 kernel/trace/trace.c              | 47 +++++++++++++++------------------------
 kernel/trace/trace.h              |  4 ----
 kernel/trace/trace_functions.c    |  8 +++----
 kernel/trace/trace_irqsoff.c      | 10 ++++-----
 kernel/trace/trace_sched_switch.c |  4 ++--
 kernel/trace/trace_sched_wakeup.c | 12 +++++-----
 7 files changed, 35 insertions(+), 52 deletions(-)

(limited to 'kernel/trace/trace_functions.c')

diff --git a/block/blktrace.c b/block/blktrace.c
index 1ebd068061ec..d9d7146ee023 100644
--- a/block/blktrace.c
+++ b/block/blktrace.c
@@ -245,7 +245,7 @@ record_it:
 			if (pid != 0 &&
 			    !(blk_tracer_flags.val & TRACE_BLK_OPT_CLASSIC) &&
 			    (trace_flags & TRACE_ITER_STACKTRACE) != 0)
-				__trace_stack(blk_tr, NULL, flags, 5, pc);
+				__trace_stack(blk_tr, flags, 5, pc);
 			trace_wake_up();
 			return;
 		}
diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c
index a5e4c0af9bb0..1d4ff568cc4d 100644
--- a/kernel/trace/trace.c
+++ b/kernel/trace/trace.c
@@ -776,7 +776,7 @@ tracing_generic_entry_update(struct trace_entry *entry, unsigned long flags,
 }
 
 void
-trace_function(struct trace_array *tr, struct trace_array_cpu *data,
+trace_function(struct trace_array *tr,
 	       unsigned long ip, unsigned long parent_ip, unsigned long flags,
 	       int pc)
 {
@@ -802,7 +802,6 @@ trace_function(struct trace_array *tr, struct trace_array_cpu *data,
 
 #ifdef CONFIG_FUNCTION_GRAPH_TRACER
 static void __trace_graph_entry(struct trace_array *tr,
-				struct trace_array_cpu *data,
 				struct ftrace_graph_ent *trace,
 				unsigned long flags,
 				int pc)
@@ -826,7 +825,6 @@ static void __trace_graph_entry(struct trace_array *tr,
 }
 
 static void __trace_graph_return(struct trace_array *tr,
-				struct trace_array_cpu *data,
 				struct ftrace_graph_ret *trace,
 				unsigned long flags,
 				int pc)
@@ -856,11 +854,10 @@ ftrace(struct trace_array *tr, struct trace_array_cpu *data,
        int pc)
 {
 	if (likely(!atomic_read(&data->disabled)))
-		trace_function(tr, data, ip, parent_ip, flags, pc);
+		trace_function(tr, ip, parent_ip, flags, pc);
 }
 
 static void __ftrace_trace_stack(struct trace_array *tr,
-				 struct trace_array_cpu *data,
 				 unsigned long flags,
 				 int skip, int pc)
 {
@@ -891,27 +888,24 @@ static void __ftrace_trace_stack(struct trace_array *tr,
 }
 
 static void ftrace_trace_stack(struct trace_array *tr,
-			       struct trace_array_cpu *data,
 			       unsigned long flags,
 			       int skip, int pc)
 {
 	if (!(trace_flags & TRACE_ITER_STACKTRACE))
 		return;
 
-	__ftrace_trace_stack(tr, data, flags, skip, pc);
+	__ftrace_trace_stack(tr, flags, skip, pc);
 }
 
 void __trace_stack(struct trace_array *tr,
-		   struct trace_array_cpu *data,
 		   unsigned long flags,
 		   int skip, int pc)
 {
-	__ftrace_trace_stack(tr, data, flags, skip, pc);
+	__ftrace_trace_stack(tr, flags, skip, pc);
 }
 
 static void ftrace_trace_userstack(struct trace_array *tr,
-		   struct trace_array_cpu *data,
-		   unsigned long flags, int pc)
+				   unsigned long flags, int pc)
 {
 #ifdef CONFIG_STACKTRACE
 	struct ring_buffer_event *event;
@@ -942,20 +936,17 @@ static void ftrace_trace_userstack(struct trace_array *tr,
 #endif
 }
 
-void __trace_userstack(struct trace_array *tr,
-		   struct trace_array_cpu *data,
-		   unsigned long flags)
+void __trace_userstack(struct trace_array *tr, unsigned long flags)
 {
-	ftrace_trace_userstack(tr, data, flags, preempt_count());
+	ftrace_trace_userstack(tr, flags, preempt_count());
 }
 
 static void
-ftrace_trace_special(void *__tr, void *__data,
+ftrace_trace_special(void *__tr,
 		     unsigned long arg1, unsigned long arg2, unsigned long arg3,
 		     int pc)
 {
 	struct ring_buffer_event *event;
-	struct trace_array_cpu *data = __data;
 	struct trace_array *tr = __tr;
 	struct special_entry *entry;
 	unsigned long irq_flags;
@@ -971,8 +962,8 @@ ftrace_trace_special(void *__tr, void *__data,
 	entry->arg2			= arg2;
 	entry->arg3			= arg3;
 	ring_buffer_unlock_commit(tr->buffer, event, irq_flags);
-	ftrace_trace_stack(tr, data, irq_flags, 4, pc);
-	ftrace_trace_userstack(tr, data, irq_flags, pc);
+	ftrace_trace_stack(tr, irq_flags, 4, pc);
+	ftrace_trace_userstack(tr, irq_flags, pc);
 
 	trace_wake_up();
 }
@@ -981,12 +972,11 @@ void
 __trace_special(void *__tr, void *__data,
 		unsigned long arg1, unsigned long arg2, unsigned long arg3)
 {
-	ftrace_trace_special(__tr, __data, arg1, arg2, arg3, preempt_count());
+	ftrace_trace_special(__tr, arg1, arg2, arg3, preempt_count());
 }
 
 void
 tracing_sched_switch_trace(struct trace_array *tr,
-			   struct trace_array_cpu *data,
 			   struct task_struct *prev,
 			   struct task_struct *next,
 			   unsigned long flags, int pc)
@@ -1010,13 +1000,12 @@ tracing_sched_switch_trace(struct trace_array *tr,
 	entry->next_state		= next->state;
 	entry->next_cpu	= task_cpu(next);
 	ring_buffer_unlock_commit(tr->buffer, event, irq_flags);
-	ftrace_trace_stack(tr, data, flags, 5, pc);
-	ftrace_trace_userstack(tr, data, flags, pc);
+	ftrace_trace_stack(tr, flags, 5, pc);
+	ftrace_trace_userstack(tr, flags, pc);
 }
 
 void
 tracing_sched_wakeup_trace(struct trace_array *tr,
-			   struct trace_array_cpu *data,
 			   struct task_struct *wakee,
 			   struct task_struct *curr,
 			   unsigned long flags, int pc)
@@ -1040,8 +1029,8 @@ tracing_sched_wakeup_trace(struct trace_array *tr,
 	entry->next_state		= wakee->state;
 	entry->next_cpu			= task_cpu(wakee);
 	ring_buffer_unlock_commit(tr->buffer, event, irq_flags);
-	ftrace_trace_stack(tr, data, flags, 6, pc);
-	ftrace_trace_userstack(tr, data, flags, pc);
+	ftrace_trace_stack(tr, flags, 6, pc);
+	ftrace_trace_userstack(tr, flags, pc);
 
 	trace_wake_up();
 }
@@ -1064,7 +1053,7 @@ ftrace_special(unsigned long arg1, unsigned long arg2, unsigned long arg3)
 	data = tr->data[cpu];
 
 	if (likely(atomic_inc_return(&data->disabled) == 1))
-		ftrace_trace_special(tr, data, arg1, arg2, arg3, pc);
+		ftrace_trace_special(tr, arg1, arg2, arg3, pc);
 
 	atomic_dec(&data->disabled);
 	local_irq_restore(flags);
@@ -1092,7 +1081,7 @@ int trace_graph_entry(struct ftrace_graph_ent *trace)
 	disabled = atomic_inc_return(&data->disabled);
 	if (likely(disabled == 1)) {
 		pc = preempt_count();
-		__trace_graph_entry(tr, data, trace, flags, pc);
+		__trace_graph_entry(tr, trace, flags, pc);
 	}
 	/* Only do the atomic if it is not already set */
 	if (!test_tsk_trace_graph(current))
@@ -1118,7 +1107,7 @@ void trace_graph_return(struct ftrace_graph_ret *trace)
 	disabled = atomic_inc_return(&data->disabled);
 	if (likely(disabled == 1)) {
 		pc = preempt_count();
-		__trace_graph_return(tr, data, trace, flags, pc);
+		__trace_graph_return(tr, trace, flags, pc);
 	}
 	if (!trace->depth)
 		clear_tsk_trace_graph(current);
diff --git a/kernel/trace/trace.h b/kernel/trace/trace.h
index f0c7a0f08cac..df627a948694 100644
--- a/kernel/trace/trace.h
+++ b/kernel/trace/trace.h
@@ -419,14 +419,12 @@ void ftrace(struct trace_array *tr,
 			    unsigned long parent_ip,
 			    unsigned long flags, int pc);
 void tracing_sched_switch_trace(struct trace_array *tr,
-				struct trace_array_cpu *data,
 				struct task_struct *prev,
 				struct task_struct *next,
 				unsigned long flags, int pc);
 void tracing_record_cmdline(struct task_struct *tsk);
 
 void tracing_sched_wakeup_trace(struct trace_array *tr,
-				struct trace_array_cpu *data,
 				struct task_struct *wakee,
 				struct task_struct *cur,
 				unsigned long flags, int pc);
@@ -436,7 +434,6 @@ void trace_special(struct trace_array *tr,
 		   unsigned long arg2,
 		   unsigned long arg3, int pc);
 void trace_function(struct trace_array *tr,
-		    struct trace_array_cpu *data,
 		    unsigned long ip,
 		    unsigned long parent_ip,
 		    unsigned long flags, int pc);
@@ -462,7 +459,6 @@ void update_max_tr_single(struct trace_array *tr,
 			  struct task_struct *tsk, int cpu);
 
 void __trace_stack(struct trace_array *tr,
-		   struct trace_array_cpu *data,
 		   unsigned long flags,
 		   int skip, int pc);
 
diff --git a/kernel/trace/trace_functions.c b/kernel/trace/trace_functions.c
index b3a320f8aba7..d067cea2ccc3 100644
--- a/kernel/trace/trace_functions.c
+++ b/kernel/trace/trace_functions.c
@@ -78,7 +78,7 @@ function_trace_call_preempt_only(unsigned long ip, unsigned long parent_ip)
 	disabled = atomic_inc_return(&data->disabled);
 
 	if (likely(disabled == 1))
-		trace_function(tr, data, ip, parent_ip, flags, pc);
+		trace_function(tr, ip, parent_ip, flags, pc);
 
 	atomic_dec(&data->disabled);
 	ftrace_preempt_enable(resched);
@@ -108,7 +108,7 @@ function_trace_call(unsigned long ip, unsigned long parent_ip)
 
 	if (likely(disabled == 1)) {
 		pc = preempt_count();
-		trace_function(tr, data, ip, parent_ip, flags, pc);
+		trace_function(tr, ip, parent_ip, flags, pc);
 	}
 
 	atomic_dec(&data->disabled);
@@ -139,7 +139,7 @@ function_stack_trace_call(unsigned long ip, unsigned long parent_ip)
 
 	if (likely(disabled == 1)) {
 		pc = preempt_count();
-		trace_function(tr, data, ip, parent_ip, flags, pc);
+		trace_function(tr, ip, parent_ip, flags, pc);
 		/*
 		 * skip over 5 funcs:
 		 *    __ftrace_trace_stack,
@@ -148,7 +148,7 @@ function_stack_trace_call(unsigned long ip, unsigned long parent_ip)
 		 *    ftrace_list_func
 		 *    ftrace_call
 		 */
-		__trace_stack(tr, data, flags, 5, pc);
+		__trace_stack(tr, flags, 5, pc);
 	}
 
 	atomic_dec(&data->disabled);
diff --git a/kernel/trace/trace_irqsoff.c b/kernel/trace/trace_irqsoff.c
index ed344b022a14..c6b442d88de8 100644
--- a/kernel/trace/trace_irqsoff.c
+++ b/kernel/trace/trace_irqsoff.c
@@ -95,7 +95,7 @@ irqsoff_tracer_call(unsigned long ip, unsigned long parent_ip)
 	disabled = atomic_inc_return(&data->disabled);
 
 	if (likely(disabled == 1))
-		trace_function(tr, data, ip, parent_ip, flags, preempt_count());
+		trace_function(tr, ip, parent_ip, flags, preempt_count());
 
 	atomic_dec(&data->disabled);
 }
@@ -153,7 +153,7 @@ check_critical_timing(struct trace_array *tr,
 	if (!report_latency(delta))
 		goto out_unlock;
 
-	trace_function(tr, data, CALLER_ADDR0, parent_ip, flags, pc);
+	trace_function(tr, CALLER_ADDR0, parent_ip, flags, pc);
 
 	latency = nsecs_to_usecs(delta);
 
@@ -177,7 +177,7 @@ out:
 	data->critical_sequence = max_sequence;
 	data->preempt_timestamp = ftrace_now(cpu);
 	tracing_reset(tr, cpu);
-	trace_function(tr, data, CALLER_ADDR0, parent_ip, flags, pc);
+	trace_function(tr, CALLER_ADDR0, parent_ip, flags, pc);
 }
 
 static inline void
@@ -210,7 +210,7 @@ start_critical_timing(unsigned long ip, unsigned long parent_ip)
 
 	local_save_flags(flags);
 
-	trace_function(tr, data, ip, parent_ip, flags, preempt_count());
+	trace_function(tr, ip, parent_ip, flags, preempt_count());
 
 	per_cpu(tracing_cpu, cpu) = 1;
 
@@ -244,7 +244,7 @@ stop_critical_timing(unsigned long ip, unsigned long parent_ip)
 	atomic_inc(&data->disabled);
 
 	local_save_flags(flags);
-	trace_function(tr, data, ip, parent_ip, flags, preempt_count());
+	trace_function(tr, ip, parent_ip, flags, preempt_count());
 	check_critical_timing(tr, data, parent_ip ? : ip, cpu);
 	data->critical_start = 0;
 	atomic_dec(&data->disabled);
diff --git a/kernel/trace/trace_sched_switch.c b/kernel/trace/trace_sched_switch.c
index df175cb4564f..c4f9add5ec90 100644
--- a/kernel/trace/trace_sched_switch.c
+++ b/kernel/trace/trace_sched_switch.c
@@ -43,7 +43,7 @@ probe_sched_switch(struct rq *__rq, struct task_struct *prev,
 	data = ctx_trace->data[cpu];
 
 	if (likely(!atomic_read(&data->disabled)))
-		tracing_sched_switch_trace(ctx_trace, data, prev, next, flags, pc);
+		tracing_sched_switch_trace(ctx_trace, prev, next, flags, pc);
 
 	local_irq_restore(flags);
 }
@@ -66,7 +66,7 @@ probe_sched_wakeup(struct rq *__rq, struct task_struct *wakee, int success)
 	data = ctx_trace->data[cpu];
 
 	if (likely(!atomic_read(&data->disabled)))
-		tracing_sched_wakeup_trace(ctx_trace, data, wakee, current,
+		tracing_sched_wakeup_trace(ctx_trace, wakee, current,
 					   flags, pc);
 
 	local_irq_restore(flags);
diff --git a/kernel/trace/trace_sched_wakeup.c b/kernel/trace/trace_sched_wakeup.c
index a48c9b4b0c85..96d716485898 100644
--- a/kernel/trace/trace_sched_wakeup.c
+++ b/kernel/trace/trace_sched_wakeup.c
@@ -72,7 +72,7 @@ wakeup_tracer_call(unsigned long ip, unsigned long parent_ip)
 	if (task_cpu(wakeup_task) != cpu)
 		goto unlock;
 
-	trace_function(tr, data, ip, parent_ip, flags, pc);
+	trace_function(tr, ip, parent_ip, flags, pc);
 
  unlock:
 	__raw_spin_unlock(&wakeup_lock);
@@ -152,8 +152,8 @@ probe_wakeup_sched_switch(struct rq *rq, struct task_struct *prev,
 	if (unlikely(!tracer_enabled || next != wakeup_task))
 		goto out_unlock;
 
-	trace_function(wakeup_trace, data, CALLER_ADDR1, CALLER_ADDR2, flags, pc);
-	tracing_sched_switch_trace(wakeup_trace, data, prev, next, flags, pc);
+	trace_function(wakeup_trace, CALLER_ADDR1, CALLER_ADDR2, flags, pc);
+	tracing_sched_switch_trace(wakeup_trace, prev, next, flags, pc);
 
 	/*
 	 * usecs conversion is slow so we try to delay the conversion
@@ -254,10 +254,8 @@ probe_wakeup(struct rq *rq, struct task_struct *p, int success)
 
 	data = wakeup_trace->data[wakeup_cpu];
 	data->preempt_timestamp = ftrace_now(cpu);
-	tracing_sched_wakeup_trace(wakeup_trace, data, p, current,
-				   flags, pc);
-	trace_function(wakeup_trace, data, CALLER_ADDR1, CALLER_ADDR2,
-		       flags, pc);
+	tracing_sched_wakeup_trace(wakeup_trace, p, current, flags, pc);
+	trace_function(wakeup_trace, CALLER_ADDR1, CALLER_ADDR2, flags, pc);
 
 out_locked:
 	__raw_spin_unlock(&wakeup_lock);
-- 
cgit v1.2.3


From b6f11df26fdc28324cf9c9e3b77f2dc985c1bb13 Mon Sep 17 00:00:00 2001
From: Arnaldo Carvalho de Melo <acme@redhat.com>
Date: Thu, 5 Feb 2009 18:02:00 -0200
Subject: trace: Call tracing_reset_online_cpus before tracer->init()
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

Impact: cleanup

To make it easy for ftrace plugin writers, as this was open coded in
the existing plugins

Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Acked-by: Frédéric Weisbecker <fweisbec@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
---
 block/blktrace.c                     |  2 --
 kernel/trace/trace.c                 |  8 +++++++-
 kernel/trace/trace.h                 |  1 +
 kernel/trace/trace_branch.c          |  1 -
 kernel/trace/trace_functions.c       | 17 +++--------------
 kernel/trace/trace_functions_graph.c |  1 -
 kernel/trace/trace_hw_branches.c     |  1 -
 kernel/trace/trace_nop.c             |  1 -
 kernel/trace/trace_sched_switch.c    |  8 +-------
 kernel/trace/trace_selftest.c        | 18 +++++++++---------
 kernel/trace/trace_sysprof.c         | 14 ++++----------
 11 files changed, 25 insertions(+), 47 deletions(-)

(limited to 'kernel/trace/trace_functions.c')

diff --git a/block/blktrace.c b/block/blktrace.c
index 834cd84037b2..ca6d32061e4f 100644
--- a/block/blktrace.c
+++ b/block/blktrace.c
@@ -1086,8 +1086,6 @@ static void blk_tracer_print_header(struct seq_file *m)
 
 static void blk_tracer_start(struct trace_array *tr)
 {
-	tracing_reset_online_cpus(tr);
-
 	mutex_lock(&blk_probe_mutex);
 	if (atomic_add_return(1, &blk_probes_ref) == 1)
 		if (blk_register_tracepoints())
diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c
index 8fad3776e843..ef4dbac95568 100644
--- a/kernel/trace/trace.c
+++ b/kernel/trace/trace.c
@@ -2171,6 +2171,12 @@ tracing_set_trace_read(struct file *filp, char __user *ubuf,
 	return simple_read_from_buffer(ubuf, cnt, ppos, buf, r);
 }
 
+int tracer_init(struct tracer *t, struct trace_array *tr)
+{
+	tracing_reset_online_cpus(tr);
+	return t->init(tr);
+}
+
 static int tracing_set_tracer(const char *buf)
 {
 	struct trace_array *tr = &global_trace;
@@ -2195,7 +2201,7 @@ static int tracing_set_tracer(const char *buf)
 
 	current_trace = t;
 	if (t->init) {
-		ret = t->init(tr);
+		ret = tracer_init(t, tr);
 		if (ret)
 			goto out;
 	}
diff --git a/kernel/trace/trace.h b/kernel/trace/trace.h
index e03f157c772e..f2742fb1575a 100644
--- a/kernel/trace/trace.h
+++ b/kernel/trace/trace.h
@@ -395,6 +395,7 @@ struct trace_iterator {
 	cpumask_var_t		started;
 };
 
+int tracer_init(struct tracer *t, struct trace_array *tr);
 int tracing_is_enabled(void);
 void trace_wake_up(void);
 void tracing_reset(struct trace_array *tr, int cpu);
diff --git a/kernel/trace/trace_branch.c b/kernel/trace/trace_branch.c
index 48b2196abe37..f8ae2c50e01d 100644
--- a/kernel/trace/trace_branch.c
+++ b/kernel/trace/trace_branch.c
@@ -131,7 +131,6 @@ static void stop_branch_trace(struct trace_array *tr)
 
 static int branch_trace_init(struct trace_array *tr)
 {
-	tracing_reset_online_cpus(tr);
 	start_branch_trace(tr);
 	return 0;
 }
diff --git a/kernel/trace/trace_functions.c b/kernel/trace/trace_functions.c
index d067cea2ccc3..36bf9568ccd9 100644
--- a/kernel/trace/trace_functions.c
+++ b/kernel/trace/trace_functions.c
@@ -24,32 +24,21 @@ static struct trace_array	*func_trace;
 static void tracing_start_function_trace(void);
 static void tracing_stop_function_trace(void);
 
-static void start_function_trace(struct trace_array *tr)
+static int function_trace_init(struct trace_array *tr)
 {
 	func_trace = tr;
 	tr->cpu = get_cpu();
-	tracing_reset_online_cpus(tr);
 	put_cpu();
 
 	tracing_start_cmdline_record();
 	tracing_start_function_trace();
-}
-
-static void stop_function_trace(struct trace_array *tr)
-{
-	tracing_stop_function_trace();
-	tracing_stop_cmdline_record();
-}
-
-static int function_trace_init(struct trace_array *tr)
-{
-	start_function_trace(tr);
 	return 0;
 }
 
 static void function_trace_reset(struct trace_array *tr)
 {
-	stop_function_trace(tr);
+	tracing_stop_function_trace();
+	tracing_stop_cmdline_record();
 }
 
 static void function_trace_start(struct trace_array *tr)
diff --git a/kernel/trace/trace_functions_graph.c b/kernel/trace/trace_functions_graph.c
index c97594d826bc..222f97d336a6 100644
--- a/kernel/trace/trace_functions_graph.c
+++ b/kernel/trace/trace_functions_graph.c
@@ -56,7 +56,6 @@ static int graph_trace_init(struct trace_array *tr)
 					&trace_graph_entry);
 	if (ret)
 		return ret;
-	tracing_reset_online_cpus(tr);
 	tracing_start_cmdline_record();
 
 	return 0;
diff --git a/kernel/trace/trace_hw_branches.c b/kernel/trace/trace_hw_branches.c
index 2aa1c9f4c7d8..ca4bbcfb9e2c 100644
--- a/kernel/trace/trace_hw_branches.c
+++ b/kernel/trace/trace_hw_branches.c
@@ -132,7 +132,6 @@ static int bts_trace_init(struct trace_array *tr)
 	hw_branch_trace = tr;
 
 	register_hotcpu_notifier(&bts_hotcpu_notifier);
-	tracing_reset_online_cpus(tr);
 	bts_trace_start(tr);
 
 	return 0;
diff --git a/kernel/trace/trace_nop.c b/kernel/trace/trace_nop.c
index 087b6cbf4ea5..9aa84bde23cd 100644
--- a/kernel/trace/trace_nop.c
+++ b/kernel/trace/trace_nop.c
@@ -48,7 +48,6 @@ static void stop_nop_trace(struct trace_array *tr)
 static int nop_trace_init(struct trace_array *tr)
 {
 	ctx_trace = tr;
-	tracing_reset_online_cpus(tr);
 	start_nop_trace(tr);
 	return 0;
 }
diff --git a/kernel/trace/trace_sched_switch.c b/kernel/trace/trace_sched_switch.c
index c4f9add5ec90..30e14fe85896 100644
--- a/kernel/trace/trace_sched_switch.c
+++ b/kernel/trace/trace_sched_switch.c
@@ -185,12 +185,6 @@ void tracing_sched_switch_assign_trace(struct trace_array *tr)
 	ctx_trace = tr;
 }
 
-static void start_sched_trace(struct trace_array *tr)
-{
-	tracing_reset_online_cpus(tr);
-	tracing_start_sched_switch_record();
-}
-
 static void stop_sched_trace(struct trace_array *tr)
 {
 	tracing_stop_sched_switch_record();
@@ -199,7 +193,7 @@ static void stop_sched_trace(struct trace_array *tr)
 static int sched_switch_trace_init(struct trace_array *tr)
 {
 	ctx_trace = tr;
-	start_sched_trace(tr);
+	tracing_start_sched_switch_record();
 	return 0;
 }
 
diff --git a/kernel/trace/trace_selftest.c b/kernel/trace/trace_selftest.c
index 5013812578b1..445700e51f6d 100644
--- a/kernel/trace/trace_selftest.c
+++ b/kernel/trace/trace_selftest.c
@@ -115,7 +115,7 @@ int trace_selftest_startup_dynamic_tracing(struct tracer *trace,
 	ftrace_set_filter(func_name, strlen(func_name), 1);
 
 	/* enable tracing */
-	ret = trace->init(tr);
+	ret = tracer_init(trace, tr);
 	if (ret) {
 		warn_failed_init_tracer(trace, ret);
 		goto out;
@@ -189,7 +189,7 @@ trace_selftest_startup_function(struct tracer *trace, struct trace_array *tr)
 	ftrace_enabled = 1;
 	tracer_enabled = 1;
 
-	ret = trace->init(tr);
+	ret = tracer_init(trace, tr);
 	if (ret) {
 		warn_failed_init_tracer(trace, ret);
 		goto out;
@@ -236,7 +236,7 @@ trace_selftest_startup_irqsoff(struct tracer *trace, struct trace_array *tr)
 	int ret;
 
 	/* start the tracing */
-	ret = trace->init(tr);
+	ret = tracer_init(trace, tr);
 	if (ret) {
 		warn_failed_init_tracer(trace, ret);
 		return ret;
@@ -290,7 +290,7 @@ trace_selftest_startup_preemptoff(struct tracer *trace, struct trace_array *tr)
 	}
 
 	/* start the tracing */
-	ret = trace->init(tr);
+	ret = tracer_init(trace, tr);
 	if (ret) {
 		warn_failed_init_tracer(trace, ret);
 		return ret;
@@ -344,7 +344,7 @@ trace_selftest_startup_preemptirqsoff(struct tracer *trace, struct trace_array *
 	}
 
 	/* start the tracing */
-	ret = trace->init(tr);
+	ret = tracer_init(trace, tr);
 	if (ret) {
 		warn_failed_init_tracer(trace, ret);
 		goto out;
@@ -476,7 +476,7 @@ trace_selftest_startup_wakeup(struct tracer *trace, struct trace_array *tr)
 	wait_for_completion(&isrt);
 
 	/* start the tracing */
-	ret = trace->init(tr);
+	ret = tracer_init(trace, tr);
 	if (ret) {
 		warn_failed_init_tracer(trace, ret);
 		return ret;
@@ -537,7 +537,7 @@ trace_selftest_startup_sched_switch(struct tracer *trace, struct trace_array *tr
 	int ret;
 
 	/* start the tracing */
-	ret = trace->init(tr);
+	ret = tracer_init(trace, tr);
 	if (ret) {
 		warn_failed_init_tracer(trace, ret);
 		return ret;
@@ -569,7 +569,7 @@ trace_selftest_startup_sysprof(struct tracer *trace, struct trace_array *tr)
 	int ret;
 
 	/* start the tracing */
-	ret = trace->init(tr);
+	ret = tracer_init(trace, tr);
 	if (ret) {
 		warn_failed_init_tracer(trace, ret);
 		return 0;
@@ -596,7 +596,7 @@ trace_selftest_startup_branch(struct tracer *trace, struct trace_array *tr)
 	int ret;
 
 	/* start the tracing */
-	ret = trace->init(tr);
+	ret = tracer_init(trace, tr);
 	if (ret) {
 		warn_failed_init_tracer(trace, ret);
 		return ret;
diff --git a/kernel/trace/trace_sysprof.c b/kernel/trace/trace_sysprof.c
index eaca5ad803ff..84ca9d81e74d 100644
--- a/kernel/trace/trace_sysprof.c
+++ b/kernel/trace/trace_sysprof.c
@@ -226,15 +226,6 @@ static void stop_stack_timers(void)
 		stop_stack_timer(cpu);
 }
 
-static void start_stack_trace(struct trace_array *tr)
-{
-	mutex_lock(&sample_timer_lock);
-	tracing_reset_online_cpus(tr);
-	start_stack_timers();
-	tracer_enabled = 1;
-	mutex_unlock(&sample_timer_lock);
-}
-
 static void stop_stack_trace(struct trace_array *tr)
 {
 	mutex_lock(&sample_timer_lock);
@@ -247,7 +238,10 @@ static int stack_trace_init(struct trace_array *tr)
 {
 	sysprof_trace = tr;
 
-	start_stack_trace(tr);
+	mutex_lock(&sample_timer_lock);
+	start_stack_timers();
+	tracer_enabled = 1;
+	mutex_unlock(&sample_timer_lock);
 	return 0;
 }
 
-- 
cgit v1.2.3


From 23b4ff3aa479c9e3bb23cb6b2d0a97878399784a Mon Sep 17 00:00:00 2001
From: Steven Rostedt <srostedt@redhat.com>
Date: Sat, 14 Feb 2009 19:04:24 -0500
Subject: ftrace: add traceon traceoff commands to enable/disable the buffers

This patch adds the new function selection commands traceon and
traceoff. traceon sets the function to enable the ring buffers
while traceoff disables the ring buffers.  You can pass in the
number of times you want the command to be executed when the function
is hit. It will only execute if the state of the buffers are not
already in that state.

Example:

 # echo do_fork:traceon:4

Will enable the ring buffers if they are disabled every time it
hits do_fork, up to 4 times.

 # echo sys_close:traceoff

This will disable the ring buffers every time (unlimited) when
sys_close is called.

Signed-off-by: Steven Rostedt <srostedt@redhat.com>
---
 kernel/trace/trace_functions.c | 135 +++++++++++++++++++++++++++++++++++++++++
 1 file changed, 135 insertions(+)

(limited to 'kernel/trace/trace_functions.c')

diff --git a/kernel/trace/trace_functions.c b/kernel/trace/trace_functions.c
index 36bf9568ccd9..5c95708b9dc3 100644
--- a/kernel/trace/trace_functions.c
+++ b/kernel/trace/trace_functions.c
@@ -9,6 +9,7 @@
  *  Copyright (C) 2004-2006 Ingo Molnar
  *  Copyright (C) 2004 William Lee Irwin III
  */
+#include <linux/ring_buffer.h>
 #include <linux/debugfs.h>
 #include <linux/uaccess.h>
 #include <linux/ftrace.h>
@@ -231,9 +232,143 @@ static struct tracer function_trace __read_mostly =
 #endif
 };
 
+#ifdef CONFIG_DYNAMIC_FTRACE
+static void
+ftrace_traceon(unsigned long ip, unsigned long parent_ip, void **data)
+{
+	long *count = (long *)data;
+
+	if (tracing_is_on())
+		return;
+
+	if (!*count)
+		return;
+
+	if (*count != -1)
+		(*count)--;
+
+	tracing_on();
+}
+
+static void
+ftrace_traceoff(unsigned long ip, unsigned long parent_ip, void **data)
+{
+	long *count = (long *)data;
+
+	if (!tracing_is_on())
+		return;
+
+	if (!*count)
+		return;
+
+	if (*count != -1)
+		(*count)--;
+
+	tracing_off();
+}
+
+static struct ftrace_hook_ops traceon_hook_ops = {
+	.func			= ftrace_traceon,
+};
+
+static struct ftrace_hook_ops traceoff_hook_ops = {
+	.func			= ftrace_traceoff,
+};
+
+static int
+ftrace_trace_onoff_unreg(char *glob, char *cmd, char *param)
+{
+	struct ftrace_hook_ops *ops;
+
+	/* we register both traceon and traceoff to this callback */
+	if (strcmp(cmd, "traceon") == 0)
+		ops = &traceon_hook_ops;
+	else
+		ops = &traceoff_hook_ops;
+
+	unregister_ftrace_function_hook_func(glob, ops);
+
+	return 0;
+}
+
+static int
+ftrace_trace_onoff_callback(char *glob, char *cmd, char *param, int enable)
+{
+	struct ftrace_hook_ops *ops;
+	void *count = (void *)-1;
+	char *number;
+	int ret;
+
+	/* hash funcs only work with set_ftrace_filter */
+	if (!enable)
+		return -EINVAL;
+
+	if (glob[0] == '!')
+		return ftrace_trace_onoff_unreg(glob+1, cmd, param);
+
+	/* we register both traceon and traceoff to this callback */
+	if (strcmp(cmd, "traceon") == 0)
+		ops = &traceon_hook_ops;
+	else
+		ops = &traceoff_hook_ops;
+
+	if (!param)
+		goto out_reg;
+
+	number = strsep(&param, ":");
+
+	if (!strlen(number))
+		goto out_reg;
+
+	/*
+	 * We use the callback data field (which is a pointer)
+	 * as our counter.
+	 */
+	ret = strict_strtoul(number, 0, (unsigned long *)&count);
+	if (ret)
+		return ret;
+
+ out_reg:
+	ret = register_ftrace_function_hook(glob, ops, count);
+
+	return ret;
+}
+
+static struct ftrace_func_command ftrace_traceon_cmd = {
+	.name			= "traceon",
+	.func			= ftrace_trace_onoff_callback,
+};
+
+static struct ftrace_func_command ftrace_traceoff_cmd = {
+	.name			= "traceoff",
+	.func			= ftrace_trace_onoff_callback,
+};
+
+static int __init init_func_cmd_traceon(void)
+{
+	int ret;
+
+	ret = register_ftrace_command(&ftrace_traceoff_cmd);
+	if (ret)
+		return ret;
+
+	ret = register_ftrace_command(&ftrace_traceon_cmd);
+	if (ret)
+		unregister_ftrace_command(&ftrace_traceoff_cmd);
+	return ret;
+}
+#else
+static inline int init_func_cmd_traceon(void)
+{
+	return 0;
+}
+#endif /* CONFIG_DYNAMIC_FTRACE */
+
 static __init int init_function_trace(void)
 {
+	init_func_cmd_traceon();
 	return register_tracer(&function_trace);
 }
 
 device_initcall(init_function_trace);
+
-- 
cgit v1.2.3


From e110e3d1eaa0f9628918be67ddd32e8ad65a2871 Mon Sep 17 00:00:00 2001
From: Steven Rostedt <srostedt@redhat.com>
Date: Mon, 16 Feb 2009 23:38:13 -0500
Subject: ftrace: add pretty print function for traceon and traceoff hooks

This patch adds a pretty print version of traceon and traceoff
output for set_ftrace_filter.

  # echo 'sys_open:traceon:4' > set_ftrace_filter
  # cat set_ftrace_filter

 #### all functions enabled ####
 sys_open:traceon:count=4

Signed-off-by: Steven Rostedt <srostedt@redhat.com>
---
 kernel/trace/trace_functions.c | 28 ++++++++++++++++++++++++++++
 1 file changed, 28 insertions(+)

(limited to 'kernel/trace/trace_functions.c')

diff --git a/kernel/trace/trace_functions.c b/kernel/trace/trace_functions.c
index 5c95708b9dc3..f520aa419dff 100644
--- a/kernel/trace/trace_functions.c
+++ b/kernel/trace/trace_functions.c
@@ -267,14 +267,42 @@ ftrace_traceoff(unsigned long ip, unsigned long parent_ip, void **data)
 	tracing_off();
 }
 
+static int
+ftrace_trace_onoff_print(struct seq_file *m, unsigned long ip,
+			 struct ftrace_hook_ops *ops, void *data);
+
 static struct ftrace_hook_ops traceon_hook_ops = {
 	.func			= ftrace_traceon,
+	.print			= ftrace_trace_onoff_print,
 };
 
 static struct ftrace_hook_ops traceoff_hook_ops = {
 	.func			= ftrace_traceoff,
+	.print			= ftrace_trace_onoff_print,
 };
 
+static int
+ftrace_trace_onoff_print(struct seq_file *m, unsigned long ip,
+			 struct ftrace_hook_ops *ops, void *data)
+{
+	char str[KSYM_SYMBOL_LEN];
+	long count = (long)data;
+
+	kallsyms_lookup(ip, NULL, NULL, NULL, str);
+	seq_printf(m, "%s:", str);
+
+	if (ops == &traceon_hook_ops)
+		seq_printf(m, "traceon");
+	else
+		seq_printf(m, "traceoff");
+
+	if (count != -1)
+		seq_printf(m, ":count=%ld", count);
+	seq_putc(m, '\n');
+
+	return 0;
+}
+
 static int
 ftrace_trace_onoff_unreg(char *glob, char *cmd, char *param)
 {
-- 
cgit v1.2.3


From 6a24a244cd3a02d5b290293c32fcf2c6e92b4235 Mon Sep 17 00:00:00 2001
From: Steven Rostedt <srostedt@redhat.com>
Date: Tue, 17 Feb 2009 11:20:26 -0500
Subject: ftrace: clean up coding style

Ingo Molnar pointed out some coding style issues with the recent ftrace
updates. This patch cleans them up.

Signed-off-by: Steven Rostedt <srostedt@redhat.com>
---
 kernel/trace/ftrace.c          | 24 +++++++++++++-----------
 kernel/trace/trace_functions.c |  1 -
 2 files changed, 13 insertions(+), 12 deletions(-)

(limited to 'kernel/trace/trace_functions.c')

diff --git a/kernel/trace/ftrace.c b/kernel/trace/ftrace.c
index 4e6c87ecf1bf..af9d95c0e4de 100644
--- a/kernel/trace/ftrace.c
+++ b/kernel/trace/ftrace.c
@@ -460,8 +460,8 @@ static void ftrace_bug(int failed, unsigned long ip)
 static int
 __ftrace_replace_code(struct dyn_ftrace *rec, int enable)
 {
-	unsigned long ip, fl;
 	unsigned long ftrace_addr;
+	unsigned long ip, fl;
 
 	ftrace_addr = (unsigned long)FTRACE_ADDR;
 
@@ -530,9 +530,9 @@ __ftrace_replace_code(struct dyn_ftrace *rec, int enable)
 
 static void ftrace_replace_code(int enable)
 {
-	int failed;
 	struct dyn_ftrace *rec;
 	struct ftrace_page *pg;
+	int failed;
 
 	do_for_each_ftrace_rec(pg, rec) {
 		/*
@@ -1208,14 +1208,15 @@ ftrace_match_record(struct dyn_ftrace *rec, char *regex, int len, int type)
 
 static void ftrace_match_records(char *buff, int len, int enable)
 {
-	char *search;
+	unsigned int search_len;
 	struct ftrace_page *pg;
 	struct dyn_ftrace *rec;
+	unsigned long flag;
+	char *search;
 	int type;
-	unsigned long flag = enable ? FTRACE_FL_FILTER : FTRACE_FL_NOTRACE;
-	unsigned search_len;
 	int not;
 
+	flag = enable ? FTRACE_FL_FILTER : FTRACE_FL_NOTRACE;
 	type = ftrace_setup_glob(buff, len, &search, &not);
 
 	search_len = strlen(search);
@@ -1263,14 +1264,16 @@ ftrace_match_module_record(struct dyn_ftrace *rec, char *mod,
 
 static void ftrace_match_module_records(char *buff, char *mod, int enable)
 {
-	char *search = buff;
+	unsigned search_len = 0;
 	struct ftrace_page *pg;
 	struct dyn_ftrace *rec;
 	int type = MATCH_FULL;
-	unsigned long flag = enable ? FTRACE_FL_FILTER : FTRACE_FL_NOTRACE;
-	unsigned search_len = 0;
+	char *search = buff;
+	unsigned long flag;
 	int not = 0;
 
+	flag = enable ? FTRACE_FL_FILTER : FTRACE_FL_NOTRACE;
+
 	/* blank or '*' mean the same */
 	if (strcmp(buff, "*") == 0)
 		buff[0] = 0;
@@ -1442,8 +1445,8 @@ register_ftrace_function_hook(char *glob, struct ftrace_hook_ops *ops,
 	struct ftrace_func_hook *entry;
 	struct ftrace_page *pg;
 	struct dyn_ftrace *rec;
-	unsigned long key;
 	int type, len, not;
+	unsigned long key;
 	int count = 0;
 	char *search;
 
@@ -1623,8 +1626,8 @@ int unregister_ftrace_command(struct ftrace_func_command *cmd)
 
 static int ftrace_process_regex(char *buff, int len, int enable)
 {
-	struct ftrace_func_command *p;
 	char *func, *command, *next = buff;
+	struct ftrace_func_command *p;
 	int ret = -EINVAL;
 
 	func = strsep(&next, ":");
@@ -2392,7 +2395,6 @@ static __init int ftrace_init_debugfs(void)
 			   "'set_ftrace_pid' entry\n");
 	return 0;
 }
-
 fs_initcall(ftrace_init_debugfs);
 
 /**
diff --git a/kernel/trace/trace_functions.c b/kernel/trace/trace_functions.c
index f520aa419dff..021a574c5988 100644
--- a/kernel/trace/trace_functions.c
+++ b/kernel/trace/trace_functions.c
@@ -397,6 +397,5 @@ static __init int init_function_trace(void)
 	init_func_cmd_traceon();
 	return register_tracer(&function_trace);
 }
-
 device_initcall(init_function_trace);
 
-- 
cgit v1.2.3


From b6887d7916e44c1d8913084fb6aa5004d9473f1a Mon Sep 17 00:00:00 2001
From: Steven Rostedt <srostedt@redhat.com>
Date: Tue, 17 Feb 2009 12:32:04 -0500
Subject: ftrace: rename _hook to _probe

Impact: clean up

Ingo Molnar did not like the _hook naming convention used by the
select function tracer. Luis Claudio R. Goncalves suggested using
the "_probe" extension. This patch implements the change of
calling the functions and variables "_hook" and replacing them
with "_probe".

Signed-off-by: Steven Rostedt <srostedt@redhat.com>
---
 include/linux/ftrace.h         | 12 +++----
 kernel/trace/ftrace.c          | 78 +++++++++++++++++++++---------------------
 kernel/trace/trace_functions.c | 26 +++++++-------
 3 files changed, 58 insertions(+), 58 deletions(-)

(limited to 'kernel/trace/trace_functions.c')

diff --git a/include/linux/ftrace.h b/include/linux/ftrace.h
index 63281228ce3e..9d224c43e634 100644
--- a/include/linux/ftrace.h
+++ b/include/linux/ftrace.h
@@ -108,7 +108,7 @@ struct ftrace_func_command {
 
 struct seq_file;
 
-struct ftrace_hook_ops {
+struct ftrace_probe_ops {
 	void			(*func)(unsigned long ip,
 					unsigned long parent_ip,
 					void **data);
@@ -116,19 +116,19 @@ struct ftrace_hook_ops {
 	void			(*free)(void **data);
 	int			(*print)(struct seq_file *m,
 					 unsigned long ip,
-					 struct ftrace_hook_ops *ops,
+					 struct ftrace_probe_ops *ops,
 					 void *data);
 };
 
 extern int
-register_ftrace_function_hook(char *glob, struct ftrace_hook_ops *ops,
+register_ftrace_function_probe(char *glob, struct ftrace_probe_ops *ops,
 			      void *data);
 extern void
-unregister_ftrace_function_hook(char *glob, struct ftrace_hook_ops *ops,
+unregister_ftrace_function_probe(char *glob, struct ftrace_probe_ops *ops,
 				void *data);
 extern void
-unregister_ftrace_function_hook_func(char *glob, struct ftrace_hook_ops *ops);
-extern void unregister_ftrace_function_hook_all(char *glob);
+unregister_ftrace_function_probe_func(char *glob, struct ftrace_probe_ops *ops);
+extern void unregister_ftrace_function_probe_all(char *glob);
 
 enum {
 	FTRACE_FL_FREE		= (1 << 0),
diff --git a/kernel/trace/ftrace.c b/kernel/trace/ftrace.c
index af9d95c0e4de..330a059f6ed7 100644
--- a/kernel/trace/ftrace.c
+++ b/kernel/trace/ftrace.c
@@ -255,9 +255,9 @@ static struct pid * const ftrace_swapper_pid = &init_struct_pid;
 
 static struct hlist_head ftrace_func_hash[FTRACE_FUNC_HASHSIZE] __read_mostly;
 
-struct ftrace_func_hook {
+struct ftrace_func_probe {
 	struct hlist_node	node;
-	struct ftrace_hook_ops	*ops;
+	struct ftrace_probe_ops	*ops;
 	unsigned long		flags;
 	unsigned long		ip;
 	void			*data;
@@ -830,11 +830,11 @@ static void *t_hash_start(struct seq_file *m, loff_t *pos)
 
 static int t_hash_show(struct seq_file *m, void *v)
 {
-	struct ftrace_func_hook *rec;
+	struct ftrace_func_probe *rec;
 	struct hlist_node *hnd = v;
 	char str[KSYM_SYMBOL_LEN];
 
-	rec = hlist_entry(hnd, struct ftrace_func_hook, node);
+	rec = hlist_entry(hnd, struct ftrace_func_probe, node);
 
 	if (rec->ops->print)
 		return rec->ops->print(m, rec->ip, rec->ops, rec->data);
@@ -1351,9 +1351,9 @@ static int __init ftrace_mod_cmd_init(void)
 device_initcall(ftrace_mod_cmd_init);
 
 static void
-function_trace_hook_call(unsigned long ip, unsigned long parent_ip)
+function_trace_probe_call(unsigned long ip, unsigned long parent_ip)
 {
-	struct ftrace_func_hook *entry;
+	struct ftrace_func_probe *entry;
 	struct hlist_head *hhd;
 	struct hlist_node *n;
 	unsigned long key;
@@ -1379,18 +1379,18 @@ function_trace_hook_call(unsigned long ip, unsigned long parent_ip)
 	ftrace_preempt_enable(resched);
 }
 
-static struct ftrace_ops trace_hook_ops __read_mostly =
+static struct ftrace_ops trace_probe_ops __read_mostly =
 {
-	.func = function_trace_hook_call,
+	.func = function_trace_probe_call,
 };
 
-static int ftrace_hook_registered;
+static int ftrace_probe_registered;
 
-static void __enable_ftrace_function_hook(void)
+static void __enable_ftrace_function_probe(void)
 {
 	int i;
 
-	if (ftrace_hook_registered)
+	if (ftrace_probe_registered)
 		return;
 
 	for (i = 0; i < FTRACE_FUNC_HASHSIZE; i++) {
@@ -1402,16 +1402,16 @@ static void __enable_ftrace_function_hook(void)
 	if (i == FTRACE_FUNC_HASHSIZE)
 		return;
 
-	__register_ftrace_function(&trace_hook_ops);
+	__register_ftrace_function(&trace_probe_ops);
 	ftrace_startup(0);
-	ftrace_hook_registered = 1;
+	ftrace_probe_registered = 1;
 }
 
-static void __disable_ftrace_function_hook(void)
+static void __disable_ftrace_function_probe(void)
 {
 	int i;
 
-	if (!ftrace_hook_registered)
+	if (!ftrace_probe_registered)
 		return;
 
 	for (i = 0; i < FTRACE_FUNC_HASHSIZE; i++) {
@@ -1421,16 +1421,16 @@ static void __disable_ftrace_function_hook(void)
 	}
 
 	/* no more funcs left */
-	__unregister_ftrace_function(&trace_hook_ops);
+	__unregister_ftrace_function(&trace_probe_ops);
 	ftrace_shutdown(0);
-	ftrace_hook_registered = 0;
+	ftrace_probe_registered = 0;
 }
 
 
 static void ftrace_free_entry_rcu(struct rcu_head *rhp)
 {
-	struct ftrace_func_hook *entry =
-		container_of(rhp, struct ftrace_func_hook, rcu);
+	struct ftrace_func_probe *entry =
+		container_of(rhp, struct ftrace_func_probe, rcu);
 
 	if (entry->ops->free)
 		entry->ops->free(&entry->data);
@@ -1439,10 +1439,10 @@ static void ftrace_free_entry_rcu(struct rcu_head *rhp)
 
 
 int
-register_ftrace_function_hook(char *glob, struct ftrace_hook_ops *ops,
+register_ftrace_function_probe(char *glob, struct ftrace_probe_ops *ops,
 			      void *data)
 {
-	struct ftrace_func_hook *entry;
+	struct ftrace_func_probe *entry;
 	struct ftrace_page *pg;
 	struct dyn_ftrace *rec;
 	int type, len, not;
@@ -1453,7 +1453,7 @@ register_ftrace_function_hook(char *glob, struct ftrace_hook_ops *ops,
 	type = ftrace_setup_glob(glob, strlen(glob), &search, &not);
 	len = strlen(search);
 
-	/* we do not support '!' for function hooks */
+	/* we do not support '!' for function probes */
 	if (WARN_ON(not))
 		return -EINVAL;
 
@@ -1468,7 +1468,7 @@ register_ftrace_function_hook(char *glob, struct ftrace_hook_ops *ops,
 
 		entry = kmalloc(sizeof(*entry), GFP_KERNEL);
 		if (!entry) {
-			/* If we did not hook to any, then return error */
+			/* If we did not process any, then return error */
 			if (!count)
 				count = -ENOMEM;
 			goto out_unlock;
@@ -1498,7 +1498,7 @@ register_ftrace_function_hook(char *glob, struct ftrace_hook_ops *ops,
 		hlist_add_head_rcu(&entry->node, &ftrace_func_hash[key]);
 
 	} while_for_each_ftrace_rec();
-	__enable_ftrace_function_hook();
+	__enable_ftrace_function_probe();
 
  out_unlock:
 	mutex_unlock(&ftrace_lock);
@@ -1507,15 +1507,15 @@ register_ftrace_function_hook(char *glob, struct ftrace_hook_ops *ops,
 }
 
 enum {
-	HOOK_TEST_FUNC		= 1,
-	HOOK_TEST_DATA		= 2
+	PROBE_TEST_FUNC		= 1,
+	PROBE_TEST_DATA		= 2
 };
 
 static void
-__unregister_ftrace_function_hook(char *glob, struct ftrace_hook_ops *ops,
+__unregister_ftrace_function_probe(char *glob, struct ftrace_probe_ops *ops,
 				  void *data, int flags)
 {
-	struct ftrace_func_hook *entry;
+	struct ftrace_func_probe *entry;
 	struct hlist_node *n, *tmp;
 	char str[KSYM_SYMBOL_LEN];
 	int type = MATCH_FULL;
@@ -1530,7 +1530,7 @@ __unregister_ftrace_function_hook(char *glob, struct ftrace_hook_ops *ops,
 		type = ftrace_setup_glob(glob, strlen(glob), &search, &not);
 		len = strlen(search);
 
-		/* we do not support '!' for function hooks */
+		/* we do not support '!' for function probes */
 		if (WARN_ON(not))
 			return;
 	}
@@ -1542,10 +1542,10 @@ __unregister_ftrace_function_hook(char *glob, struct ftrace_hook_ops *ops,
 		hlist_for_each_entry_safe(entry, n, tmp, hhd, node) {
 
 			/* break up if statements for readability */
-			if ((flags & HOOK_TEST_FUNC) && entry->ops != ops)
+			if ((flags & PROBE_TEST_FUNC) && entry->ops != ops)
 				continue;
 
-			if ((flags & HOOK_TEST_DATA) && entry->data != data)
+			if ((flags & PROBE_TEST_DATA) && entry->data != data)
 				continue;
 
 			/* do this last, since it is the most expensive */
@@ -1560,27 +1560,27 @@ __unregister_ftrace_function_hook(char *glob, struct ftrace_hook_ops *ops,
 			call_rcu(&entry->rcu, ftrace_free_entry_rcu);
 		}
 	}
-	__disable_ftrace_function_hook();
+	__disable_ftrace_function_probe();
 	mutex_unlock(&ftrace_lock);
 }
 
 void
-unregister_ftrace_function_hook(char *glob, struct ftrace_hook_ops *ops,
+unregister_ftrace_function_probe(char *glob, struct ftrace_probe_ops *ops,
 				void *data)
 {
-	__unregister_ftrace_function_hook(glob, ops, data,
-					  HOOK_TEST_FUNC | HOOK_TEST_DATA);
+	__unregister_ftrace_function_probe(glob, ops, data,
+					  PROBE_TEST_FUNC | PROBE_TEST_DATA);
 }
 
 void
-unregister_ftrace_function_hook_func(char *glob, struct ftrace_hook_ops *ops)
+unregister_ftrace_function_probe_func(char *glob, struct ftrace_probe_ops *ops)
 {
-	__unregister_ftrace_function_hook(glob, ops, NULL, HOOK_TEST_FUNC);
+	__unregister_ftrace_function_probe(glob, ops, NULL, PROBE_TEST_FUNC);
 }
 
-void unregister_ftrace_function_hook_all(char *glob)
+void unregister_ftrace_function_probe_all(char *glob)
 {
-	__unregister_ftrace_function_hook(glob, NULL, NULL, 0);
+	__unregister_ftrace_function_probe(glob, NULL, NULL, 0);
 }
 
 static LIST_HEAD(ftrace_commands);
diff --git a/kernel/trace/trace_functions.c b/kernel/trace/trace_functions.c
index 021a574c5988..6ea73ed03bfa 100644
--- a/kernel/trace/trace_functions.c
+++ b/kernel/trace/trace_functions.c
@@ -269,21 +269,21 @@ ftrace_traceoff(unsigned long ip, unsigned long parent_ip, void **data)
 
 static int
 ftrace_trace_onoff_print(struct seq_file *m, unsigned long ip,
-			 struct ftrace_hook_ops *ops, void *data);
+			 struct ftrace_probe_ops *ops, void *data);
 
-static struct ftrace_hook_ops traceon_hook_ops = {
+static struct ftrace_probe_ops traceon_probe_ops = {
 	.func			= ftrace_traceon,
 	.print			= ftrace_trace_onoff_print,
 };
 
-static struct ftrace_hook_ops traceoff_hook_ops = {
+static struct ftrace_probe_ops traceoff_probe_ops = {
 	.func			= ftrace_traceoff,
 	.print			= ftrace_trace_onoff_print,
 };
 
 static int
 ftrace_trace_onoff_print(struct seq_file *m, unsigned long ip,
-			 struct ftrace_hook_ops *ops, void *data)
+			 struct ftrace_probe_ops *ops, void *data)
 {
 	char str[KSYM_SYMBOL_LEN];
 	long count = (long)data;
@@ -291,7 +291,7 @@ ftrace_trace_onoff_print(struct seq_file *m, unsigned long ip,
 	kallsyms_lookup(ip, NULL, NULL, NULL, str);
 	seq_printf(m, "%s:", str);
 
-	if (ops == &traceon_hook_ops)
+	if (ops == &traceon_probe_ops)
 		seq_printf(m, "traceon");
 	else
 		seq_printf(m, "traceoff");
@@ -306,15 +306,15 @@ ftrace_trace_onoff_print(struct seq_file *m, unsigned long ip,
 static int
 ftrace_trace_onoff_unreg(char *glob, char *cmd, char *param)
 {
-	struct ftrace_hook_ops *ops;
+	struct ftrace_probe_ops *ops;
 
 	/* we register both traceon and traceoff to this callback */
 	if (strcmp(cmd, "traceon") == 0)
-		ops = &traceon_hook_ops;
+		ops = &traceon_probe_ops;
 	else
-		ops = &traceoff_hook_ops;
+		ops = &traceoff_probe_ops;
 
-	unregister_ftrace_function_hook_func(glob, ops);
+	unregister_ftrace_function_probe_func(glob, ops);
 
 	return 0;
 }
@@ -322,7 +322,7 @@ ftrace_trace_onoff_unreg(char *glob, char *cmd, char *param)
 static int
 ftrace_trace_onoff_callback(char *glob, char *cmd, char *param, int enable)
 {
-	struct ftrace_hook_ops *ops;
+	struct ftrace_probe_ops *ops;
 	void *count = (void *)-1;
 	char *number;
 	int ret;
@@ -336,9 +336,9 @@ ftrace_trace_onoff_callback(char *glob, char *cmd, char *param, int enable)
 
 	/* we register both traceon and traceoff to this callback */
 	if (strcmp(cmd, "traceon") == 0)
-		ops = &traceon_hook_ops;
+		ops = &traceon_probe_ops;
 	else
-		ops = &traceoff_hook_ops;
+		ops = &traceoff_probe_ops;
 
 	if (!param)
 		goto out_reg;
@@ -357,7 +357,7 @@ ftrace_trace_onoff_callback(char *glob, char *cmd, char *param, int enable)
 		return ret;
 
  out_reg:
-	ret = register_ftrace_function_hook(glob, ops, count);
+	ret = register_ftrace_function_probe(glob, ops, count);
 
 	return ret;
 }
-- 
cgit v1.2.3


From 35ebf1caa4854ad5ba25f3a72967acc064147994 Mon Sep 17 00:00:00 2001
From: Steven Rostedt <srostedt@redhat.com>
Date: Tue, 17 Feb 2009 13:12:12 -0500
Subject: ftrace: show unlimited when traceon or traceoff has no counter

Impact: clean up

The traceon and traceoff function probes are confusing to developers
to what happens when a counter is not specified. This should help
clear things up.

 # echo "*:traceoff" > set_ftrace_filter
 # cat /debug/tracing/set_ftrace_filter

  #### all functions enabled ####
  do_fork:traceoff:unlimited

Signed-off-by: Steven Rostedt <srostedt@redhat.com>
---
 kernel/trace/trace_functions.c | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

(limited to 'kernel/trace/trace_functions.c')

diff --git a/kernel/trace/trace_functions.c b/kernel/trace/trace_functions.c
index 6ea73ed03bfa..4c113a8c466f 100644
--- a/kernel/trace/trace_functions.c
+++ b/kernel/trace/trace_functions.c
@@ -296,7 +296,9 @@ ftrace_trace_onoff_print(struct seq_file *m, unsigned long ip,
 	else
 		seq_printf(m, "traceoff");
 
-	if (count != -1)
+	if (count == -1)
+		seq_printf(m, ":unlimited\n");
+	else
 		seq_printf(m, ":count=%ld", count);
 	seq_putc(m, '\n');
 
-- 
cgit v1.2.3


From 6eaaa5d57e76c454479833fc8594cd7c3b75c789 Mon Sep 17 00:00:00 2001
From: Frederic Weisbecker <fweisbec@gmail.com>
Date: Wed, 11 Feb 2009 02:25:00 +0100
Subject: tracing/core: use appropriate waiting on trace_pipe

Impact: api and pipe waiting change

Currently, the waiting used in tracing_read_pipe() is done through a
100 msecs schedule_timeout() loop which periodically check if there
are traces on the buffer.

This can cause small latencies for programs which are reading the incoming
events.

This patch makes the reader waiting for the trace_wait waitqueue except
for few tracers such as the sched and functions tracers which might be
already hold the runqueue lock while waking up the reader.

This is performed through a new callback wait_pipe() on struct tracer.
If none is implemented on a specific tracer, the default waiting for
trace_wait queue is attached.

Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
---
 kernel/trace/trace.c                 | 62 ++++++++++++++++++++++++------------
 kernel/trace/trace.h                 | 25 +++++++++++++--
 kernel/trace/trace_functions.c       |  1 +
 kernel/trace/trace_functions_graph.c |  1 +
 kernel/trace/trace_sched_switch.c    |  1 +
 kernel/trace/trace_sched_wakeup.c    |  1 +
 6 files changed, 67 insertions(+), 24 deletions(-)

(limited to 'kernel/trace/trace_functions.c')

diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c
index dc61e82faad9..881a94474d79 100644
--- a/kernel/trace/trace.c
+++ b/kernel/trace/trace.c
@@ -499,6 +499,9 @@ __acquires(kernel_lock)
 	else
 		if (!type->flags->opts)
 			type->flags->opts = dummy_tracer_opt;
+	if (!type->wait_pipe)
+		type->wait_pipe = default_wait_pipe;
+
 
 #ifdef CONFIG_FTRACE_STARTUP_TEST
 	if (type->selftest && !tracing_selftest_disabled) {
@@ -1064,7 +1067,10 @@ tracing_sched_wakeup_trace(struct trace_array *tr,
 	entry->next_prio		= wakee->prio;
 	entry->next_state		= wakee->state;
 	entry->next_cpu			= task_cpu(wakee);
-	trace_buffer_unlock_commit(tr, event, flags, pc);
+
+	ring_buffer_unlock_commit(tr->buffer, event);
+	ftrace_trace_stack(tr, flags, 6, pc);
+	ftrace_trace_userstack(tr, flags, pc);
 }
 
 void
@@ -2392,6 +2398,38 @@ tracing_poll_pipe(struct file *filp, poll_table *poll_table)
 	}
 }
 
+
+void default_wait_pipe(struct trace_iterator *iter)
+{
+	DEFINE_WAIT(wait);
+
+	prepare_to_wait(&trace_wait, &wait, TASK_INTERRUPTIBLE);
+
+	if (trace_empty(iter))
+		schedule();
+
+	finish_wait(&trace_wait, &wait);
+}
+
+/*
+ * This is a make-shift waitqueue.
+ * A tracer might use this callback on some rare cases:
+ *
+ *  1) the current tracer might hold the runqueue lock when it wakes up
+ *     a reader, hence a deadlock (sched, function, and function graph tracers)
+ *  2) the function tracers, trace all functions, we don't want
+ *     the overhead of calling wake_up and friends
+ *     (and tracing them too)
+ *
+ *     Anyway, this is really very primitive wakeup.
+ */
+void poll_wait_pipe(struct trace_iterator *iter)
+{
+	set_current_state(TASK_INTERRUPTIBLE);
+	/* sleep for 100 msecs, and try again. */
+	schedule_timeout(HZ / 10);
+}
+
 /* Must be called with trace_types_lock mutex held. */
 static int tracing_wait_pipe(struct file *filp)
 {
@@ -2403,30 +2441,14 @@ static int tracing_wait_pipe(struct file *filp)
 			return -EAGAIN;
 		}
 
-		/*
-		 * This is a make-shift waitqueue. The reason we don't use
-		 * an actual wait queue is because:
-		 *  1) we only ever have one waiter
-		 *  2) the tracing, traces all functions, we don't want
-		 *     the overhead of calling wake_up and friends
-		 *     (and tracing them too)
-		 *     Anyway, this is really very primitive wakeup.
-		 */
-		set_current_state(TASK_INTERRUPTIBLE);
-		iter->tr->waiter = current;
-
 		mutex_unlock(&trace_types_lock);
 
-		/* sleep for 100 msecs, and try again. */
-		schedule_timeout(HZ/10);
+		iter->trace->wait_pipe(iter);
 
 		mutex_lock(&trace_types_lock);
 
-		iter->tr->waiter = NULL;
-
-		if (signal_pending(current)) {
+		if (signal_pending(current))
 			return -EINTR;
-		}
 
 		if (iter->trace != current_trace)
 			return 0;
@@ -2442,8 +2464,6 @@ static int tracing_wait_pipe(struct file *filp)
 		 */
 		if (!tracer_enabled && iter->pos)
 			break;
-
-		continue;
 	}
 
 	return 1;
diff --git a/kernel/trace/trace.h b/kernel/trace/trace.h
index dbff0207b213..eed732c151fc 100644
--- a/kernel/trace/trace.h
+++ b/kernel/trace/trace.h
@@ -337,18 +337,34 @@ struct tracer_flags {
 #define TRACER_OPT(s, b)	.name = #s, .bit = b
 
 
-/*
- * A specific tracer, represented by methods that operate on a trace array:
+/**
+ * struct tracer - a specific tracer and its callbacks to interact with debugfs
+ * @name: the name chosen to select it on the available_tracers file
+ * @init: called when one switches to this tracer (echo name > current_tracer)
+ * @reset: called when one switches to another tracer
+ * @start: called when tracing is unpaused (echo 1 > tracing_enabled)
+ * @stop: called when tracing is paused (echo 0 > tracing_enabled)
+ * @open: called when the trace file is opened
+ * @pipe_open: called when the trace_pipe file is opened
+ * @wait_pipe: override how the user waits for traces on trace_pipe
+ * @close: called when the trace file is released
+ * @read: override the default read callback on trace_pipe
+ * @splice_read: override the default splice_read callback on trace_pipe
+ * @selftest: selftest to run on boot (see trace_selftest.c)
+ * @print_headers: override the first lines that describe your columns
+ * @print_line: callback that prints a trace
+ * @set_flag: signals one of your private flags changed (trace_options file)
+ * @flags: your private flags
  */
 struct tracer {
 	const char		*name;
-	/* Your tracer should raise a warning if init fails */
 	int			(*init)(struct trace_array *tr);
 	void			(*reset)(struct trace_array *tr);
 	void			(*start)(struct trace_array *tr);
 	void			(*stop)(struct trace_array *tr);
 	void			(*open)(struct trace_iterator *iter);
 	void			(*pipe_open)(struct trace_iterator *iter);
+	void			(*wait_pipe)(struct trace_iterator *iter);
 	void			(*close)(struct trace_iterator *iter);
 	ssize_t			(*read)(struct trace_iterator *iter,
 					struct file *filp, char __user *ubuf,
@@ -432,6 +448,9 @@ void tracing_generic_entry_update(struct trace_entry *entry,
 				  unsigned long flags,
 				  int pc);
 
+void default_wait_pipe(struct trace_iterator *iter);
+void poll_wait_pipe(struct trace_iterator *iter);
+
 void ftrace(struct trace_array *tr,
 			    struct trace_array_cpu *data,
 			    unsigned long ip,
diff --git a/kernel/trace/trace_functions.c b/kernel/trace/trace_functions.c
index 4c113a8c466f..c9a0b7df44ff 100644
--- a/kernel/trace/trace_functions.c
+++ b/kernel/trace/trace_functions.c
@@ -225,6 +225,7 @@ static struct tracer function_trace __read_mostly =
 	.init		= function_trace_init,
 	.reset		= function_trace_reset,
 	.start		= function_trace_start,
+	.wait_pipe	= poll_wait_pipe,
 	.flags		= &func_flags,
 	.set_flag	= func_set_flag,
 #ifdef CONFIG_FTRACE_SELFTEST
diff --git a/kernel/trace/trace_functions_graph.c b/kernel/trace/trace_functions_graph.c
index 519a0cab1530..0ff5cb661900 100644
--- a/kernel/trace/trace_functions_graph.c
+++ b/kernel/trace/trace_functions_graph.c
@@ -757,6 +757,7 @@ static struct tracer graph_trace __read_mostly = {
 	.name	     	= "function_graph",
 	.open		= graph_trace_open,
 	.close		= graph_trace_close,
+	.wait_pipe	= poll_wait_pipe,
 	.init	     	= graph_trace_init,
 	.reset	     	= graph_trace_reset,
 	.print_line	= print_graph_function,
diff --git a/kernel/trace/trace_sched_switch.c b/kernel/trace/trace_sched_switch.c
index 82fbb5a2df89..77132c2cf3d9 100644
--- a/kernel/trace/trace_sched_switch.c
+++ b/kernel/trace/trace_sched_switch.c
@@ -221,6 +221,7 @@ static struct tracer sched_switch_trace __read_mostly =
 	.reset		= sched_switch_trace_reset,
 	.start		= sched_switch_trace_start,
 	.stop		= sched_switch_trace_stop,
+	.wait_pipe	= poll_wait_pipe,
 #ifdef CONFIG_FTRACE_SELFTEST
 	.selftest    = trace_selftest_startup_sched_switch,
 #endif
diff --git a/kernel/trace/trace_sched_wakeup.c b/kernel/trace/trace_sched_wakeup.c
index 276c51aaf314..db55f7aaa640 100644
--- a/kernel/trace/trace_sched_wakeup.c
+++ b/kernel/trace/trace_sched_wakeup.c
@@ -380,6 +380,7 @@ static struct tracer wakeup_rt_tracer __read_mostly =
 	.reset		= wakeup_tracer_reset,
 	.start		= wakeup_tracer_start,
 	.stop		= wakeup_tracer_stop,
+	.wait_pipe	= poll_wait_pipe,
 	.print_max	= 1,
 #ifdef CONFIG_FTRACE_SELFTEST
 	.selftest    = trace_selftest_startup_wakeup,
-- 
cgit v1.2.3