ftrace: Add unit test for removing trace function

A self test is provided for the trace function removal functionality.

Link: https://lkml.kernel.org/r/20210918153043.318016-2-carles.pey@gmail.com
Signed-off-by: Carles Pey <carles.pey@gmail.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>

diff --git a/kernel/trace/trace_selftest.c b/kernel/trace/trace_selftest.c
index adf7ef1..875b4f1 100644 (file)
--- a/kernel/trace/trace_selftest.c
+++ b/kernel/trace/trace_selftest.c
@@ -287,6 +287,40 @@ static int trace_selftest_ops(struct trace_array *tr, int cnt)
        if (trace_selftest_test_probe3_cnt != 4)
                goto out_free;
 
+       /* Remove trace function from probe 3 */
+       func1_name = "!" __stringify(DYN_FTRACE_TEST_NAME);
+       len1 = strlen(func1_name);
+
+       ftrace_set_filter(&test_probe3, func1_name, len1, 0);
+
+       DYN_FTRACE_TEST_NAME();
+
+       print_counts();
+
+       if (trace_selftest_test_probe1_cnt != 3)
+               goto out_free;
+       if (trace_selftest_test_probe2_cnt != 2)
+               goto out_free;
+       if (trace_selftest_test_probe3_cnt != 4)
+               goto out_free;
+       if (cnt > 1) {
+               if (trace_selftest_test_global_cnt == 0)
+                       goto out_free;
+       }
+       if (trace_selftest_test_dyn_cnt == 0)
+               goto out_free;
+
+       DYN_FTRACE_TEST_NAME2();
+
+       print_counts();
+
+       if (trace_selftest_test_probe1_cnt != 3)
+               goto out_free;
+       if (trace_selftest_test_probe2_cnt != 3)
+               goto out_free;
+       if (trace_selftest_test_probe3_cnt != 5)
+               goto out_free;
+
        ret = 0;
  out_free:
        unregister_ftrace_function(dyn_ops);