Re: Stepping over signals, in state "detaching" did not handle handleStoppedEvent SIGTRAP(5)

[Andrew Cagney <cagney at redhat dot com>]

I suspect that this:

        //    System.err.println("BreakPoint.addedTo");
-        ((Task) observable).requestDeleteInstructionObserver(this.steppingEngine.getSteppingObserver());
+        Task task = (Task) observable;
+        this.steppingEngine.requestRemoveSteppingObserver(task); 

is likely at least part of the problem - I see it's also pre-existing code.  Breakpoints shouldn't be rooting around in the stepping engine.  

+    
+    public void stepOverSignal(Task task) {
+	DebugInfoFrame frame = DebugInfoStackFactory
+	    .createDebugInfoStackTrace(task);
+	
+	long address = frame.getAddress();
+
+	fine.log(this, "Looking for address: 0x", Long.toHexString(address), "Line #: ", frame.getLine().getLine());
+	
+	TaskStepEngine tse = (TaskStepEngine) this.taskStateMap.get(task);
+	tse.setState(new StepOutState(task));
+	this.steppingObserver.notifyNotBlocked(tse);
+
+	int i = ((Integer) this.contextMap.get(task.getProc())).intValue();
+	this.contextMap.put(task.getProc(), new Integer(++i));

what I believe is happening is that this code:
+
+	this.breakpoint = new SteppingBreakpoint(this, address);

is removing the stepping-engine's observer before this:

+	this.breakpointMap.put(task, this.breakpoint);
+	task.requestAddCodeObserver(this.breakpoint, address);

has had a chance to install the breakpoint.

A better sequence is:

-> create breakpoint
-> request add breakpoint
-> request remove stepping observer


I believe Teresa was also looking at this.

Andrew

PS: Can the test-case be changed to assembler?  As C it is going to run into portability problems.


+    }



Nurdin Premji wrote:
> Here is current work on stepping over a signal, the race condition 
> involved is:
> inside frysk-core:
>
> ./TestRunner -debug frysk.stepping.SteppingEngine=FINE 
> frysk.stepping.TestStepping.testStepOverSignal
>
> There was 1 error:
> 1) 
> testStepOverSignal(frysk.stepping.TestStepping)java.lang.RuntimeException: 
> {frysk.proc.live.LinuxPtraceTask@327b6455,pid=29497,tid=29497,state=detaching} 
> in state "detaching" did not handle handleStoppedEvent SIGTRAP(5)
>   at frysk.proc.live.State.unhandled(TestRunner)
>   at 
> frysk.proc.live.LinuxPtraceTaskState$2.handleStoppedEvent(TestRunner)
>   at frysk.proc.live.LinuxPtraceTask.processStoppedEvent(TestRunner)
>   at frysk.proc.live.LinuxWaitBuilder.stopped(TestRunner)
>   at frysk.sys.Wait.wait(TestRunner)
>   at frysk.sys.Wait.wait(TestRunner)
>   at frysk.event.WaitEventLoop.block(TestRunner)
>   at frysk.event.EventLoop.runEventLoop(TestRunner)
>   at frysk.event.EventLoop.runPolling(TestRunner)
>   at frysk.testbed.TestLib.assertRunUntilStop(TestRunner)
>   at frysk.testbed.TestLib.assertRunUntilStop(TestRunner)
>   at frysk.stepping.TestStepping.testStepOverSignal(TestRunner)
>   at frysk.junit.Runner.runCases(TestRunner)
>   at frysk.junit.Runner.runTestCases(TestRunner)
>   at TestRunner.main(TestRunner)
>
>
> happens quite frequently but every once in a while get a pass