4 files changed, 121 insertions, 113 deletions

diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c
index 1b73acb..0cfd1a6 100644
--- a/kernel/trace/trace.c
+++ b/kernel/trace/trace.c
@@ -942,54 +942,6 @@ trace_function(struct trace_array *tr,
 		ring_buffer_unlock_commit(tr->buffer, event);
 }
 
-#ifdef CONFIG_FUNCTION_GRAPH_TRACER
-static int __trace_graph_entry(struct trace_array *tr,
-				struct ftrace_graph_ent *trace,
-				unsigned long flags,
-				int pc)
-{
-	struct ftrace_event_call *call = &event_funcgraph_entry;
-	struct ring_buffer_event *event;
-	struct ftrace_graph_ent_entry *entry;
-
-	if (unlikely(local_read(&__get_cpu_var(ftrace_cpu_disabled))))
-		return 0;
-
-	event = trace_buffer_lock_reserve(&global_trace, TRACE_GRAPH_ENT,
-					  sizeof(*entry), flags, pc);
-	if (!event)
-		return 0;
-	entry	= ring_buffer_event_data(event);
-	entry->graph_ent			= *trace;
-	if (!filter_current_check_discard(call, entry, event))
-		ring_buffer_unlock_commit(global_trace.buffer, event);
-
-	return 1;
-}
-
-static void __trace_graph_return(struct trace_array *tr,
-				struct ftrace_graph_ret *trace,
-				unsigned long flags,
-				int pc)
-{
-	struct ftrace_event_call *call = &event_funcgraph_exit;
-	struct ring_buffer_event *event;
-	struct ftrace_graph_ret_entry *entry;
-
-	if (unlikely(local_read(&__get_cpu_var(ftrace_cpu_disabled))))
-		return;
-
-	event = trace_buffer_lock_reserve(&global_trace, TRACE_GRAPH_RET,
-					  sizeof(*entry), flags, pc);
-	if (!event)
-		return;
-	entry	= ring_buffer_event_data(event);
-	entry->ret				= *trace;
-	if (!filter_current_check_discard(call, entry, event))
-		ring_buffer_unlock_commit(global_trace.buffer, event);
-}
-#endif
-
 void
 ftrace(struct trace_array *tr, struct trace_array_cpu *data,
        unsigned long ip, unsigned long parent_ip, unsigned long flags,
@@ -1129,68 +1081,6 @@ ftrace_special(unsigned long arg1, unsigned long arg2, unsigned long arg3)
 	local_irq_restore(flags);
 }
 
-#ifdef CONFIG_FUNCTION_GRAPH_TRACER
-int trace_graph_entry(struct ftrace_graph_ent *trace)
-{
-	struct trace_array *tr = &global_trace;
-	struct trace_array_cpu *data;
-	unsigned long flags;
-	long disabled;
-	int ret;
-	int cpu;
-	int pc;
-
-	if (!ftrace_trace_task(current))
-		return 0;
-
-	if (!ftrace_graph_addr(trace->func))
-		return 0;
-
-	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();
-		ret = __trace_graph_entry(tr, trace, flags, pc);
-	} else {
-		ret = 0;
-	}
-	/* Only do the atomic if it is not already set */
-	if (!test_tsk_trace_graph(current))
-		set_tsk_trace_graph(current);
-
-	atomic_dec(&data->disabled);
-	local_irq_restore(flags);
-
-	return ret;
-}
-
-void trace_graph_return(struct ftrace_graph_ret *trace)
-{
-	struct trace_array *tr = &global_trace;
-	struct trace_array_cpu *data;
-	unsigned long flags;
-	long disabled;
-	int cpu;
-	int pc;
-
-	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_graph_return(tr, trace, flags, pc);
-	}
-	if (!trace->depth)
-		clear_tsk_trace_graph(current);
-	atomic_dec(&data->disabled);
-	local_irq_restore(flags);
-}
-#endif /* CONFIG_FUNCTION_GRAPH_TRACER */
-
-
 /**
  * trace_vbprintk - write binary msg to tracing buffer
  *
diff --git a/kernel/trace/trace.h b/kernel/trace/trace.h
index 116524d..9301f12 100644
--- a/kernel/trace/trace.h
+++ b/kernel/trace/trace.h
@@ -471,6 +471,7 @@ void trace_function(struct trace_array *tr,
 
 void trace_graph_return(struct ftrace_graph_ret *trace);
 int trace_graph_entry(struct ftrace_graph_ent *trace);
+void set_graph_array(struct trace_array *tr);
 
 void tracing_start_cmdline_record(void);
 void tracing_stop_cmdline_record(void);
diff --git a/kernel/trace/trace_functions_graph.c b/kernel/trace/trace_functions_graph.c
index e30472d..f97244a 100644
--- a/kernel/trace/trace_functions_graph.c
+++ b/kernel/trace/trace_functions_graph.c
@@ -52,7 +52,7 @@ static struct tracer_flags tracer_flags = {
 	.opts = trace_opts
 };
 
-/* pid on the last trace processed */
+static struct trace_array *graph_array;
 
 
 /* Add a function return address to the trace stack on thread info.*/
@@ -166,10 +166,121 @@ unsigned long ftrace_return_to_handler(unsigned long frame_pointer)
 	return ret;
 }
 
+static int __trace_graph_entry(struct trace_array *tr,
+				struct ftrace_graph_ent *trace,
+				unsigned long flags,
+				int pc)
+{
+	struct ftrace_event_call *call = &event_funcgraph_entry;
+	struct ring_buffer_event *event;
+	struct ftrace_graph_ent_entry *entry;
+
+	if (unlikely(local_read(&__get_cpu_var(ftrace_cpu_disabled))))
+		return 0;
+
+	event = trace_buffer_lock_reserve(tr, TRACE_GRAPH_ENT,
+					  sizeof(*entry), flags, pc);
+	if (!event)
+		return 0;
+	entry	= ring_buffer_event_data(event);
+	entry->graph_ent			= *trace;
+	if (!filter_current_check_discard(call, entry, event))
+		ring_buffer_unlock_commit(tr->buffer, event);
+
+	return 1;
+}
+
+int trace_graph_entry(struct ftrace_graph_ent *trace)
+{
+	struct trace_array *tr = graph_array;
+	struct trace_array_cpu *data;
+	unsigned long flags;
+	long disabled;
+	int ret;
+	int cpu;
+	int pc;
+
+	if (unlikely(!tr))
+		return 0;
+
+	if (!ftrace_trace_task(current))
+		return 0;
+
+	if (!ftrace_graph_addr(trace->func))
+		return 0;
+
+	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();
+		ret = __trace_graph_entry(tr, trace, flags, pc);
+	} else {
+		ret = 0;
+	}
+	/* Only do the atomic if it is not already set */
+	if (!test_tsk_trace_graph(current))
+		set_tsk_trace_graph(current);
+
+	atomic_dec(&data->disabled);
+	local_irq_restore(flags);
+
+	return ret;
+}
+
+static void __trace_graph_return(struct trace_array *tr,
+				struct ftrace_graph_ret *trace,
+				unsigned long flags,
+				int pc)
+{
+	struct ftrace_event_call *call = &event_funcgraph_exit;
+	struct ring_buffer_event *event;
+	struct ftrace_graph_ret_entry *entry;
+
+	if (unlikely(local_read(&__get_cpu_var(ftrace_cpu_disabled))))
+		return;
+
+	event = trace_buffer_lock_reserve(tr, TRACE_GRAPH_RET,
+					  sizeof(*entry), flags, pc);
+	if (!event)
+		return;
+	entry	= ring_buffer_event_data(event);
+	entry->ret				= *trace;
+	if (!filter_current_check_discard(call, entry, event))
+		ring_buffer_unlock_commit(tr->buffer, event);
+}
+
+void trace_graph_return(struct ftrace_graph_ret *trace)
+{
+	struct trace_array *tr = graph_array;
+	struct trace_array_cpu *data;
+	unsigned long flags;
+	long disabled;
+	int cpu;
+	int pc;
+
+	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_graph_return(tr, trace, flags, pc);
+	}
+	if (!trace->depth)
+		clear_tsk_trace_graph(current);
+	atomic_dec(&data->disabled);
+	local_irq_restore(flags);
+}
+
 static int graph_trace_init(struct trace_array *tr)
 {
-	int ret = register_ftrace_graph(&trace_graph_return,
-					&trace_graph_entry);
+	int ret;
+
+	graph_array = tr;
+	ret = register_ftrace_graph(&trace_graph_return,
+				    &trace_graph_entry);
 	if (ret)
 		return ret;
 	tracing_start_cmdline_record();
@@ -177,6 +288,11 @@ static int graph_trace_init(struct trace_array *tr)
 	return 0;
 }
 
+void set_graph_array(struct trace_array *tr)
+{
+	graph_array = tr;
+}
+
 static void graph_trace_reset(struct trace_array *tr)
 {
 	tracing_stop_cmdline_record();
diff --git a/kernel/trace/trace_selftest.c b/kernel/trace/trace_selftest.c
index 00dd648..d2cdbab 100644
--- a/kernel/trace/trace_selftest.c
+++ b/kernel/trace/trace_selftest.c
@@ -288,6 +288,7 @@ trace_selftest_startup_function_graph(struct tracer *trace,
 	 * to detect and recover from possible hangs
 	 */
 	tracing_reset_online_cpus(tr);
+	set_graph_array(tr);
 	ret = register_ftrace_graph(&trace_graph_return,
 				    &trace_graph_entry_watchdog);
 	if (ret) {