Ensure async actions do not get traced

Since they run non-deterministically, the tests can randomly fail,
and the debugger can jump into some unrelated weakref callback,
making tracing them undesirable.

Author: Adam Hrbac

graalpython/com.oracle.graal.python.test/src/tests/test_sys_settrace.py

@@ -40,6 +40,7 @@
 import unittest
 import difflib
 import sys
+import signal
 
 import builtins
 
@@ -198,3 +199,21 @@ def fun1():
                   (12, 'fun1', 'line', None)]
         if self.events != events:
             self.fail('\n'+'\n'.join(difflib.ndiff([str(x) for x in events], [str(x) for x in self.events])))
+
+    def simpler_trace(self, fr, ev, arg):
+        self.events.append(fr.f_code.co_name)
+
+    @unittest.skipIf(not hasattr(signal, 'SIGUSR1'), "User defined signal not present")
+    def test_07_async_actions_not_traced(self):
+        def handler(*_): handler.called = 1
+
+        def helper(): return 1
+        signal.signal(signal.SIGUSR1, handler)
+        self.events = []
+        sys.settrace(self.simpler_trace)
+        signal.raise_signal(signal.SIGUSR1)
+        for i in range(1000): helper()
+        sys.settrace(None)
+        # handler.called is not checked, since it could cause a transient
+        for name in self.events:
+            self.assertEqual(name, 'helper')

graalpython/com.oracle.graal.python/src/com/oracle/graal/python/nodes/bytecode/PBytecodeRootNode.java

@@ -203,7 +203,6 @@
 import com.oracle.truffle.api.HostCompilerDirectives.InliningCutoff;
 import com.oracle.truffle.api.Truffle;
 import com.oracle.truffle.api.TruffleLanguage;
-import com.oracle.truffle.api.TruffleSafepoint;
 import com.oracle.truffle.api.exception.AbstractTruffleException;
 import com.oracle.truffle.api.frame.Frame;
 import com.oracle.truffle.api.frame.FrameDescriptor;
@@ -1883,7 +1882,7 @@ private Object bytecodeLoop(VirtualFrame virtualFrame, Frame localFrame, Bytecod
                                 }
                             }
                         }
-                        TruffleSafepoint.poll(this);
+                        PythonContext.triggerAsyncActions(this);
                         oparg = 0;
                         continue;
                     }
@@ -2332,6 +2331,7 @@ private void invokeTraceFunction(VirtualFrame virtualFrame, Object arg, PythonCo
         if (threadState.isTracing()) {
             return;
         }
+        assert event != PythonContext.TraceEvent.DISABLED;
         threadState.tracingStart(event);
         PFrame pyFrame = mutableData.setPyFrame(ensurePyFrame(virtualFrame, mutableData.getPyFrame()));
         Object traceFn = useLocalFn ? pyFrame.getLocalTraceFun() : threadState.getTraceFun();

graalpython/com.oracle.graal.python/src/com/oracle/graal/python/runtime/AsyncHandler.java

@@ -122,6 +122,8 @@ protected boolean proceed() {
         @Override
         public final void execute(PythonContext context) {
             Debugger debugger = null;
+            PythonContext.PythonThreadState threadState = null;
+            PythonLanguage language = context.getLanguage();
             do {
                 Object callable = callable();
                 if (callable != null) {
@@ -136,6 +138,13 @@ public final void execute(PythonContext context) {
                     if (debugger == null) {
                         debugger = Debugger.find(context.getEnv());
                     }
+                    if (threadState == null) {
+                        threadState = context.getThreadState(language);
+                    }
+                    boolean alreadyTracing = threadState.isTracing();
+                    if (!alreadyTracing) {
+                        threadState.tracingStart(PythonContext.TraceEvent.DISABLED);
+                    }
                     debugger.disableStepping();
                     try {
                         GenericInvokeNode.getUncached().execute(context.getAsyncHandler().callTarget, args);
@@ -148,6 +157,9 @@ public final void execute(PythonContext context) {
                         ExceptionUtils.printPythonLikeStackTrace(e);
                     } finally {
                         debugger.restoreStepping();
+                        if (!alreadyTracing) {
+                            threadState.tracingStop();
+                        }
                     }
                 }
             } while (proceed());

graalpython/com.oracle.graal.python/src/com/oracle/graal/python/runtime/PythonContext.java

@@ -191,7 +191,8 @@ public enum TraceEvent {
         CALL("call"),
         EXCEPTION("exception"),
         LINE("line"),
-        RETURN("return");
+        RETURN("return"),
+        DISABLED("");
 
         public final TruffleString pythonName;