ftrace: Access ret_stack->subtime only in the function profiler
The subtime is used only for function profiler with function graph
tracer enabled. Move the definition of subtime under
CONFIG_FUNCTION_PROFILER to reduce the memory usage. Also move the
initialization of subtime into the graph entry callback.
Link: http://lkml.kernel.org/r/20160831025529.24018-1-namhyung@kernel.org
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
diff --git a/include/linux/ftrace.h b/include/linux/ftrace.h
index 7d565af..1e2b316 100644
--- a/include/linux/ftrace.h
+++ b/include/linux/ftrace.h
@@ -794,7 +794,9 @@
unsigned long ret;
unsigned long func;
unsigned long long calltime;
+#ifdef CONFIG_FUNCTION_PROFILER
unsigned long long subtime;
+#endif
unsigned long fp;
};