Merge "simpleperf: support dynamic field in simpleperf_report_lib.py."

2 files changed, 26 insertions, 1 deletions

diff --git a/simpleperf/scripts/simpleperf_report_lib.py b/simpleperf/scripts/simpleperf_report_lib.py
index a46c2242..2b99602f 100644
--- a/simpleperf/scripts/simpleperf_report_lib.py
+++ b/simpleperf/scripts/simpleperf_report_lib.py
@@ -83,12 +83,14 @@ class TracingFieldFormatStruct(ct.Structure):
        elem_size: size of the element type.
        elem_count: the number of elements in this field, more than one if the field is an array.
        is_signed: whether the element type is signed or unsigned.
+       is_dynamic: whether the element is a dynamic string.
     """
     _fields_ = [('_name', ct.c_char_p),
                 ('offset', ct.c_uint32),
                 ('elem_size', ct.c_uint32),
                 ('elem_count', ct.c_uint32),
-                ('is_signed', ct.c_uint32)]
+                ('is_signed', ct.c_uint32),
+                ('is_dynamic', ct.c_uint32)]
 
     _unpack_key_dict = {1: 'b', 2: 'h', 4: 'i', 8: 'q'}
 
@@ -102,6 +104,13 @@ class TracingFieldFormatStruct(ct.Structure):
             an array of int values, etc. If the type can't be parsed, return a byte array or an
             array of byte arrays.
         """
+        if self.is_dynamic:
+            offset, max_len = struct.unpack('<HH', data[self.offset:self.offset + 4])
+            length = 0
+            while length < max_len and bytes_to_str(data[offset + length]) != '\x00':
+                length += 1
+            return bytes_to_str(data[offset: offset + length])
+
         if self.elem_count > 1 and self.elem_size == 1:
             # Probably the field is a string.
             # Don't use self.is_signed, which has different values on x86 and arm.
diff --git a/simpleperf/scripts/test.py b/simpleperf/scripts/test.py
index be1a855c..14efc326 100755
--- a/simpleperf/scripts/test.py
+++ b/simpleperf/scripts/test.py
@@ -1114,6 +1114,22 @@ class TestReportLib(TestBase):
                 self.assertIsNone(tracing_data)
         self.assertTrue(has_tracing_data)
 
+    def test_dynamic_field_in_tracing_data(self):
+        self.report_lib.SetRecordFile(TEST_HELPER.testdata_path(
+            'perf_with_tracepoint_event_dynamic_field.data'))
+        has_dynamic_field = False
+        while self.report_lib.GetNextSample():
+            event = self.report_lib.GetEventOfCurrentSample()
+            tracing_data = self.report_lib.GetTracingDataOfCurrentSample()
+            if event.name == 'kprobes:myopen':
+                self.assertIsNotNone(tracing_data)
+                self.assertIn('name', tracing_data)
+                if tracing_data['name'] == '/sys/kernel/debug/tracing/events/kprobes/myopen/format':
+                    has_dynamic_field = True
+            else:
+                self.assertIsNone(tracing_data)
+        self.assertTrue(has_dynamic_field)
+
 
 class TestRunSimpleperfOnDevice(TestBase):
     def test_smoke(self):