1 files changed, 59 insertions, 1 deletions

diff --git a/arch/sparc/kernel/ftrace.c b/arch/sparc/kernel/ftrace.c
index 9103a56b39e8..03ab022e51c5 100644
--- a/arch/sparc/kernel/ftrace.c
+++ b/arch/sparc/kernel/ftrace.c
@@ -13,7 +13,7 @@ static const u32 ftrace_nop = 0x01000000;
 
 static u32 ftrace_call_replace(unsigned long ip, unsigned long addr)
 {
-        static u32 call;
+        u32 call;
         s32 off;
 
         off = ((s32)addr - (s32)ip);
@@ -91,3 +91,61 @@ int __init ftrace_dyn_arch_init(void *data)
         return 0;
 }
 #endif
+
+#ifdef CONFIG_FUNCTION_GRAPH_TRACER
+
+#ifdef CONFIG_DYNAMIC_FTRACE
+extern void ftrace_graph_call(void);
+
+int ftrace_enable_ftrace_graph_caller(void)
+{
+        unsigned long ip = (unsigned long)(&ftrace_graph_call);
+        u32 old, new;
+
+        old = *(u32 *) &ftrace_graph_call;
+        new = ftrace_call_replace(ip, (unsigned long) &ftrace_graph_caller);
+        return ftrace_modify_code(ip, old, new);
+}
+
+int ftrace_disable_ftrace_graph_caller(void)
+{
+        unsigned long ip = (unsigned long)(&ftrace_graph_call);
+        u32 old, new;
+
+        old = *(u32 *) &ftrace_graph_call;
+        new = ftrace_call_replace(ip, (unsigned long) &ftrace_stub);
+
+        return ftrace_modify_code(ip, old, new);
+}
+
+#endif /* !CONFIG_DYNAMIC_FTRACE */
+
+/*
+ * Hook the return address and push it in the stack of return addrs
+ * in current thread info.
+ */
+unsigned long prepare_ftrace_return(unsigned long parent,
+                                    unsigned long self_addr,
+                                    unsigned long frame_pointer)
+{
+        unsigned long return_hooker = (unsigned long) &return_to_handler;
+        struct ftrace_graph_ent trace;
+
+        if (unlikely(atomic_read(&current->tracing_graph_pause)))
+                return parent + 8UL;
+
+        if (ftrace_push_return_trace(parent, self_addr, &trace.depth,
+                                     frame_pointer) == -EBUSY)
+                return parent + 8UL;
+
+        trace.func = self_addr;
+
+        /* Only trace if the calling function expects to */
+        if (!ftrace_graph_entry(&trace)) {
+                current->curr_ret_stack--;
+                return parent + 8UL;
+        }
+
+        return return_hooker;
+}
+#endif /* CONFIG_FUNCTION_GRAPH_TRACER */