tracing/fastboot: only trace non-module initcalls

At this time, only built-in initcalls interest us.
We can't really produce a relevant graph if we include
the modules initcall too.

I had good results after this patch (see svg in attachment).

Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>

3 files changed, 11 insertions, 3 deletions

diff --git a/include/linux/ftrace.h b/include/linux/ftrace.h
index ed53265d1f63..5812dba4ee24 100644
--- a/include/linux/ftrace.h
+++ b/include/linux/ftrace.h
@@ -225,9 +225,11 @@ struct boot_trace {
 #ifdef CONFIG_BOOT_TRACER
 extern void trace_boot(struct boot_trace *it, initcall_t fn);
 extern void start_boot_trace(void);
+extern void stop_boot_trace(void);
 #else
 static inline void trace_boot(struct boot_trace *it, initcall_t fn) { }
 static inline void start_boot_trace(void) { }
+static inline void stop_boot_trace(void) { }
 #endif
 
 
diff --git a/init/main.c b/init/main.c
index 8e96a0ef17f4..e7939de80f3e 100644
--- a/init/main.c
+++ b/init/main.c
@@ -886,6 +886,7 @@ static int __init kernel_init(void * unused)
          * we're essentially up and running. Get rid of the
          * initmem segments and start the user-mode stuff..
          */
+        stop_boot_trace();
         init_post();
         return 0;
 }
diff --git a/kernel/trace/trace_boot.c b/kernel/trace/trace_boot.c
index b9dc2c0093ab..a7efe3559654 100644
--- a/kernel/trace/trace_boot.c
+++ b/kernel/trace/trace_boot.c
@@ -22,11 +22,16 @@ void start_boot_trace(void)
         trace_boot_enabled = 1;
 }
 
-void stop_boot_trace(struct trace_array *tr)
+void stop_boot_trace(void)
 {
         trace_boot_enabled = 0;
 }
 
+void reset_boot_trace(struct trace_array *tr)
+{
+        stop_boot_trace();
+}
+
 static void boot_trace_init(struct trace_array *tr)
 {
         int cpu;
@@ -43,7 +48,7 @@ static void boot_trace_ctrl_update(struct trace_array *tr)
         if (tr->ctrl)
                 start_boot_trace();
         else
-                stop_boot_trace(tr);
+                stop_boot_trace();
 }
 
 static enum print_line_t initcall_print_line(struct trace_iterator *iter)
@@ -81,7 +86,7 @@ struct tracer boot_tracer __read_mostly =
 {
         .name           = "initcall",
         .init           = boot_trace_init,
-        .reset          = stop_boot_trace,
+        .reset          = reset_boot_trace,
         .ctrl_update    = boot_trace_ctrl_update,
         .print_line     = initcall_print_line,
 };