python3 compat: tracepoint fixes

Signed-off-by: Brenden Blanco <bblanco@gmail.com>

src/python/bcc/__init__.py

@@ -1046,7 +1046,8 @@ class BPF(object):
         for k, v in self.open_tracepoints.items():
             lib.perf_reader_free(v)
             (tp_category, tp_name) = k.split(':')
-            lib.bpf_detach_tracepoint(tp_category, tp_name)
+            lib.bpf_detach_tracepoint(tp_category.encode("ascii"),
+                    tp_name.encode("ascii"))
         self.open_tracepoints.clear()
         for (ev_type, ev_config) in list(self.open_perf_events.keys()):
             self.detach_perf_event(ev_type, ev_config)

tests/python/test_tracepoint.py

@@ -61,10 +61,8 @@ class TestTracepointDataLoc(unittest.TestCase):
         b = bcc.BPF(text=text)
         subprocess.check_output(["/bin/ls"])
         sleep(1)
-        found = False
-        for k, v in b["execs"].items():
-            found = "ls" in v.filename
-        self.assertTrue(found, "'ls' was not found in map")
+        self.assertTrue("/bin/ls" in [v.filename.decode()
+                                      for v in b["execs"].values()])
 
 if __name__ == "__main__":
     unittest.main()