1 files changed, 31 insertions, 19 deletions

diff --git a/tools/perf/util/scripting-engines/trace-event-python.c b/tools/perf/util/scripting-engines/trace-event-python.c
index e87aa5d9696b..53c20e7fd900 100644
--- a/tools/perf/util/scripting-engines/trace-event-python.c
+++ b/tools/perf/util/scripting-engines/trace-event-python.c
@@ -56,6 +56,17 @@ static void handler_call_die(const char *handler_name)
         Py_FatalError("problem in Python trace event handler");
 }
 
+/*
+ * Insert val into into the dictionary and decrement the reference counter.
+ * This is necessary for dictionaries since PyDict_SetItemString() does not 
+ * steal a reference, as opposed to PyTuple_SetItem().
+ */
+static void pydict_set_item_string_decref(PyObject *dict, const char *key, PyObject *val)
+{
+        PyDict_SetItemString(dict, key, val);
+        Py_DECREF(val);
+}
+
 static void define_value(enum print_arg_type field_type,
                          const char *ev_name,
                          const char *field_name,
@@ -225,6 +236,7 @@ static void python_process_tracepoint(union perf_event *perf_event
                                  struct perf_sample *sample,
                                  struct perf_evsel *evsel,
                                  struct machine *machine __maybe_unused,
+                                 struct thread *thread,
                                  struct addr_location *al)
 {
         PyObject *handler, *retval, *context, *t, *obj, *dict = NULL;
@@ -238,8 +250,7 @@ static void python_process_tracepoint(union perf_event *perf_event
         int cpu = sample->cpu;
         void *data = sample->raw_data;
         unsigned long long nsecs = sample->time;
-        struct thread *thread = al->thread;
-        char *comm = thread->comm;
+        const char *comm = thread__comm_str(thread);
 
         t = PyTuple_New(MAX_FIELDS);
         if (!t)
@@ -279,11 +290,11 @@ static void python_process_tracepoint(union perf_event *perf_event
                 PyTuple_SetItem(t, n++, PyInt_FromLong(pid));
                 PyTuple_SetItem(t, n++, PyString_FromString(comm));
         } else {
-                PyDict_SetItemString(dict, "common_cpu", PyInt_FromLong(cpu));
-                PyDict_SetItemString(dict, "common_s", PyInt_FromLong(s));
-                PyDict_SetItemString(dict, "common_ns", PyInt_FromLong(ns));
-                PyDict_SetItemString(dict, "common_pid", PyInt_FromLong(pid));
-                PyDict_SetItemString(dict, "common_comm", PyString_FromString(comm));
+                pydict_set_item_string_decref(dict, "common_cpu", PyInt_FromLong(cpu));
+                pydict_set_item_string_decref(dict, "common_s", PyInt_FromLong(s));
+                pydict_set_item_string_decref(dict, "common_ns", PyInt_FromLong(ns));
+                pydict_set_item_string_decref(dict, "common_pid", PyInt_FromLong(pid));
+                pydict_set_item_string_decref(dict, "common_comm", PyString_FromString(comm));
         }
         for (field = event->format.fields; field; field = field->next) {
                 if (field->flags & FIELD_IS_STRING) {
@@ -313,7 +324,7 @@ static void python_process_tracepoint(union perf_event *perf_event
                 if (handler)
                         PyTuple_SetItem(t, n++, obj);
                 else
-                        PyDict_SetItemString(dict, field->name, obj);
+                        pydict_set_item_string_decref(dict, field->name, obj);
 
         }
         if (!handler)
@@ -345,12 +356,12 @@ static void python_process_general_event(union perf_event *perf_event
                                          struct perf_sample *sample,
                                          struct perf_evsel *evsel,
                                          struct machine *machine __maybe_unused,
+                                         struct thread *thread,
                                          struct addr_location *al)
 {
         PyObject *handler, *retval, *t, *dict;
         static char handler_name[64];
         unsigned n = 0;
-        struct thread *thread = al->thread;
 
         /*
          * Use the MAX_FIELDS to make the function expandable, though
@@ -370,21 +381,21 @@ static void python_process_general_event(union perf_event *perf_event
         if (!handler || !PyCallable_Check(handler))
                 goto exit;
 
-        PyDict_SetItemString(dict, "ev_name", PyString_FromString(perf_evsel__name(evsel)));
-        PyDict_SetItemString(dict, "attr", PyString_FromStringAndSize(
+        pydict_set_item_string_decref(dict, "ev_name", PyString_FromString(perf_evsel__name(evsel)));
+        pydict_set_item_string_decref(dict, "attr", PyString_FromStringAndSize(
                         (const char *)&evsel->attr, sizeof(evsel->attr)));
-        PyDict_SetItemString(dict, "sample", PyString_FromStringAndSize(
+        pydict_set_item_string_decref(dict, "sample", PyString_FromStringAndSize(
                         (const char *)sample, sizeof(*sample)));
-        PyDict_SetItemString(dict, "raw_buf", PyString_FromStringAndSize(
+        pydict_set_item_string_decref(dict, "raw_buf", PyString_FromStringAndSize(
                         (const char *)sample->raw_data, sample->raw_size));
-        PyDict_SetItemString(dict, "comm",
-                        PyString_FromString(thread->comm));
+        pydict_set_item_string_decref(dict, "comm",
+                        PyString_FromString(thread__comm_str(thread)));
         if (al->map) {
-                PyDict_SetItemString(dict, "dso",
+                pydict_set_item_string_decref(dict, "dso",
                         PyString_FromString(al->map->dso->name));
         }
         if (al->sym) {
-                PyDict_SetItemString(dict, "symbol",
+                pydict_set_item_string_decref(dict, "symbol",
                         PyString_FromString(al->sym->name));
         }
 
@@ -404,17 +415,18 @@ static void python_process_event(union perf_event *perf_event,
                                  struct perf_sample *sample,
                                  struct perf_evsel *evsel,
                                  struct machine *machine,
+                                 struct thread *thread,
                                  struct addr_location *al)
 {
         switch (evsel->attr.type) {
         case PERF_TYPE_TRACEPOINT:
                 python_process_tracepoint(perf_event, sample, evsel,
-                                          machine, al);
+                                          machine, thread, al);
                 break;
         /* Reserve for future process_hw/sw/raw APIs */
         default:
                 python_process_general_event(perf_event, sample, evsel,
-                                             machine, al);
+                                             machine, thread, al);
         }
 }