ftrace: Return pt_regs to function trace callback

Return as the 4th paramater to the function tracer callback the pt_regs.

Later patches that implement regs passing for the architectures will require
having the ftrace_ops set the SAVE_REGS flag, which will tell the arch
to take the time to pass a full set of pt_regs to the ftrace_ops callback
function. If the arch does not support it then it should pass NULL.

If an arch can pass full regs, then it should define:
 ARCH_SUPPORTS_FTRACE_SAVE_REGS to 1

Link: http://lkml.kernel.org/r/20120702201821.019966811@goodmis.org

Reviewed-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>

1 files changed, 4 insertions, 3 deletions

diff --git a/kernel/trace/trace_functions.c b/kernel/trace/trace_functions.c
index fceb7a9aa06d..5675ebd541f0 100644
--- a/kernel/trace/trace_functions.c
+++ b/kernel/trace/trace_functions.c
@@ -49,7 +49,7 @@ static void function_trace_start(struct trace_array *tr)
 
 static void
 function_trace_call_preempt_only(unsigned long ip, unsigned long parent_ip,
-                                 struct ftrace_ops *op)
+                                 struct ftrace_ops *op, struct pt_regs *pt_regs)
 {
         struct trace_array *tr = func_trace;
         struct trace_array_cpu *data;
@@ -77,7 +77,8 @@ function_trace_call_preempt_only(unsigned long ip, unsigned long parent_ip,
 
 static void
 function_trace_call(unsigned long ip, unsigned long parent_ip,
-                    struct ftrace_ops *op)
+                    struct ftrace_ops *op, struct pt_regs *pt_regs)
+
 {
         struct trace_array *tr = func_trace;
         struct trace_array_cpu *data;
@@ -109,7 +110,7 @@ function_trace_call(unsigned long ip, unsigned long parent_ip,
 
 static void
 function_stack_trace_call(unsigned long ip, unsigned long parent_ip,
-                          struct ftrace_ops *op)
+                          struct ftrace_ops *op, struct pt_regs *pt_regs)
 {
         struct trace_array *tr = func_trace;
         struct trace_array_cpu *data;