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authorDavid S. Miller <davem@davemloft.net>2010-04-07 04:41:33 -0700
committerDavid S. Miller <davem@davemloft.net>2010-04-12 22:37:26 -0700
commit9960e9e8944f9b1ca6af5f7d26400ca45b429600 (patch)
tree2483b4c55f54663a8cc358fae5837e7d8232c554 /arch/sparc/kernel/ftrace.c
parenta71d1d6bb1b26e566e5c06c37857f4cdc1664780 (diff)
sparc64: Add function graph tracer support.
Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'arch/sparc/kernel/ftrace.c')
-rw-r--r--arch/sparc/kernel/ftrace.c58
1 files changed, 58 insertions, 0 deletions
diff --git a/arch/sparc/kernel/ftrace.c b/arch/sparc/kernel/ftrace.c
index 2ea6e4ff7fd2..03ab022e51c5 100644
--- a/arch/sparc/kernel/ftrace.c
+++ b/arch/sparc/kernel/ftrace.c
@@ -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 */