tracing: use union for multi-usages field

Impact: cleanup

struct dyn_ftrace::ip has different usages in his lifecycle,
we use union for it. And also for struct dyn_ftrace::flags.

Signed-off-by: Lai Jiangshan <[email protected]>
Cc: Steven Rostedt <[email protected]>
Cc: Frederic Weisbecker <[email protected]>
LKML-Reference: <[email protected]>
Signed-off-by: Ingo Molnar <[email protected]>

1 files changed, 9 insertions, 3 deletions

diff --git a/include/linux/ftrace.h b/include/linux/ftrace.h
index 1141248c84ee..015a3d22cf74 100644
--- a/include/linux/ftrace.h
+++ b/include/linux/ftrace.h
@@ -145,9 +145,15 @@ enum {
 };
 
 struct dyn_ftrace {
-	unsigned long		ip; /* address of mcount call-site */
-	unsigned long		flags;
-	struct dyn_arch_ftrace	arch;
+	union {
+		unsigned long		ip; /* address of mcount call-site */
+		struct dyn_ftrace	*freelist;
+	};
+	union {
+		unsigned long		flags;
+		struct dyn_ftrace	*newlist;
+	};
+	struct dyn_arch_ftrace		arch;
 };
 
 int ftrace_force_update(void);