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>

1 files changed, 36 insertions, 25 deletions

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
 };