ftrace: Have function graph tracer use global_ops for filtering

Commit 4104d326b670 "ftrace: Remove global function list and call
function directly" cleaned up the global_ops filtering and made
the code simpler. But it left out function graph filtering which
also depended on that code. The function graph filtering still
needs to use global_ops as the filter otherwise it wont filter
at all.

Signed-off-by: Steven Rostedt <rostedt@goodmis.org>

1 files changed, 6 insertions, 8 deletions

diff --git a/kernel/trace/ftrace.c b/kernel/trace/ftrace.c
index 34b098bfded4..9eb1aa03a18d 100644
--- a/kernel/trace/ftrace.c
+++ b/kernel/trace/ftrace.c
@@ -5008,12 +5008,6 @@ ftrace_suspend_notifier_call(struct notifier_block *bl, unsigned long state,
         return NOTIFY_DONE;
 }
 
-/* Just a place holder for function graph */
-static struct ftrace_ops fgraph_ops __read_mostly = {
-        .func           = ftrace_stub,
-        .flags          = FTRACE_OPS_FL_STUB | FTRACE_OPS_FL_RECURSION_SAFE,
-};
-
 static int ftrace_graph_entry_test(struct ftrace_graph_ent *trace)
 {
         if (!ftrace_ops_test(&global_ops, trace->func, NULL))
@@ -5076,7 +5070,10 @@ int register_ftrace_graph(trace_func_graph_ret_t retfunc,
         ftrace_graph_entry = ftrace_graph_entry_test;
         update_function_graph_func();
 
-        ret = ftrace_startup(&fgraph_ops, FTRACE_START_FUNC_RET);
+        /* Function graph doesn't use the .func field of global_ops */
+        global_ops.flags |= FTRACE_OPS_FL_STUB;
+
+        ret = ftrace_startup(&global_ops, FTRACE_START_FUNC_RET);
 
 out:
         mutex_unlock(&ftrace_lock);
@@ -5094,7 +5091,8 @@ void unregister_ftrace_graph(void)
         ftrace_graph_return = (trace_func_graph_ret_t)ftrace_stub;
         ftrace_graph_entry = ftrace_graph_entry_stub;
         __ftrace_graph_entry = ftrace_graph_entry_stub;
-        ftrace_shutdown(&fgraph_ops, FTRACE_STOP_FUNC_RET);
+        ftrace_shutdown(&global_ops, FTRACE_STOP_FUNC_RET);
+        global_ops.flags &= ~FTRACE_OPS_FL_STUB;
         unregister_pm_notifier(&ftrace_suspend_notifier);
         unregister_trace_sched_switch(ftrace_graph_probe_sched_switch, NULL);