tracing: Add ftrace events for graph tracer

Add ftrace events for graph tracer, so the graph output could be shared
with other tracers.

Signed-off-by: Jiri Olsa <jolsa@redhat.com>
LKML-Reference: <1270227683-14631-2-git-send-email-jolsa@redhat.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>

1 files changed, 27 insertions, 1 deletions

diff --git a/kernel/trace/trace_functions_graph.c b/kernel/trace/trace_functions_graph.c
index 669b9c31861d..db9e06bb766e 100644
--- a/kernel/trace/trace_functions_graph.c
+++ b/kernel/trace/trace_functions_graph.c
@@ -40,7 +40,7 @@ struct fgraph_data {
 #define TRACE_GRAPH_PRINT_OVERHEAD      0x4
 #define TRACE_GRAPH_PRINT_PROC          0x8
 #define TRACE_GRAPH_PRINT_DURATION      0x10
-#define TRACE_GRAPH_PRINT_ABS_TIME      0X20
+#define TRACE_GRAPH_PRINT_ABS_TIME      0x20
 
 static struct tracer_opt trace_opts[] = {
         /* Display overruns? (for self-debug purpose) */
@@ -1096,6 +1096,12 @@ print_graph_function(struct trace_iterator *iter)
         return TRACE_TYPE_HANDLED;
 }
 
+static enum print_line_t
+print_graph_function_event(struct trace_iterator *iter, int flags)
+{
+        return print_graph_function(iter);
+}
+
 static void print_lat_header(struct seq_file *s)
 {
         static const char spaces[] = "                " /* 16 spaces */
@@ -1199,6 +1205,16 @@ static void graph_trace_close(struct trace_iterator *iter)
         }
 }
 
+static struct trace_event graph_trace_entry_event = {
+        .type           = TRACE_GRAPH_ENT,
+        .trace          = print_graph_function_event,
+};
+
+static struct trace_event graph_trace_ret_event = {
+        .type           = TRACE_GRAPH_RET,
+        .trace          = print_graph_function_event,
+};
+
 static struct tracer graph_trace __read_mostly = {
         .name           = "function_graph",
         .open           = graph_trace_open,
@@ -1220,6 +1236,16 @@ static __init int init_graph_trace(void)
 {
         max_bytes_for_cpu = snprintf(NULL, 0, "%d", nr_cpu_ids - 1);
 
+        if (!register_ftrace_event(&graph_trace_entry_event)) {
+                pr_warning("Warning: could not register graph trace events\n");
+                return 1;
+        }
+
+        if (!register_ftrace_event(&graph_trace_ret_event)) {
+                pr_warning("Warning: could not register graph trace events\n");
+                return 1;
+        }
+
         return register_tracer(&graph_trace);
 }