Hi Gary,

Overall it looks good.

Is the EventHandler.isDisconnected() check needed?

In resume008a.java you removed a lot of empty lines. In some places it's fine, but the lines at 132 and 134 should have remained. Also, for the ones that were ok to remove, I don't see you doing the same thing in the other files. I think probably it's best to be consistent, and for this webrev probably best not to do them since it distracts too much from the important changes.

Seems like there is a lot of abstraction that could have been done with these tests to share a lot of code, but since so far that hasn't been done, probably not a good idea to start doing that with this fix. Do you think it's worth filing an enhancement request for?

thanks,

Chris

On 8/3/18 11:04 AM, Gary Adams wrote:
Here is an updated webrev with the alternate solution implemented for
resume 1 to 10. The debugger sets testCase variable in the debuggee
when each test case completes in the debugger. By having the debuggee
wait for the debugger to complete with test case 0, it avoids the interference
that occurs by proceeding to the breakpoint set in MethodForCommunication
before the debugger has compared expected suspend counts.

  Webrev: http://cr.openjdk.java.net/~gadams/8170089/webrev.01/index.html

On 7/17/18, 11:33 AM, Gary Adams wrote:
A race condition exists between the debugger and the debuggee.

The first test thread is started with SUSPEND_NONE policy set.
While processing the thread start event the debugger captures
an initial set of thread suspend counts and resumes the
debuggee vm. If the debuggee advances quickly it reaches
the breakpoint set for methodForCommunication. Since the breakpoint
carries with it SUSPEND_ALL policy, when the debugger captures a second
set of suspend counts, it will not match the expected counts for
a SUSPEND_NONE scenario.

The proposed fix introduces a yield in the debuggee test thread run method
to allow the debugger to get the expected sampled values.

  Issue: https://bugs.openjdk.java.net/browse/JDK-8170089
  Webrev: http://cr.openjdk.java.net/~gadams/8170089/webrev.00/


test/hotspot/jtreg/vmTestbase/nsk/share/jdi/TestDebuggerType1.java:
...
   186        private void setCommunicationBreakpoint(ReferenceType refType, String methodName) {    187            Method method = debuggee.methodByName(refType, methodName);
   188            Location location = null;
   189            try {
   190                location = method.allLineLocations().get(0);
   191            } catch (AbsentInformationException e) {
   192                throw new Failure(e);
   193            }
   194            bpRequest = debuggee.makeBreakpoint(location);
   195

   196 bpRequest.setSuspendPolicy(EventRequest.SUSPEND_ALL);

   197            bpRequest.putProperty("number", "zero");
   198            bpRequest.enable();
   199
   200            eventHandler.addListener(
   201                 new EventHandler.EventListener() {
   202                     public boolean eventReceived(Event event) {
   203                        if (event instanceof BreakpointEvent && bpRequest.equals(event.request())) {
   204                            synchronized(eventHandler) {
   205                                display("Received communication breakpoint event.");
   206                                bpCount++;
   207                                eventHandler.notifyAll();
   208                            }
   209                            return true;
   210                        }
   211                        return false;
   212                     }
   213                 }
   214            );
   215        }


test/hotspot/jtreg/vmTestbase/nsk/jdi/EventSet/resume/resume008.java:
...
   140                    display("......--> vm.suspend();");
   141                    vm.suspend();
   142
   143                    display("        getting : Map<String, Integer> suspendsCounts1");
   144
   145                    Map<String, Integer> suspendsCounts1 = new HashMap<String, Integer>();    146                    for (ThreadReference threadReference : vm.allThreads()) {    147 suspendsCounts1.put(threadReference.name(), threadReference.suspendCount());
   148                    }
   149                    display(suspendsCounts1.toString());
   150
   151                    display("        eventSet.resume;");
   152                    eventSet.resume();
   153
   154                    display("        getting : Map<String, Integer> suspendsCounts2");

This is where the breakpoint is encountered before the second set of suspend counts is acquired.

   155                    Map<String, Integer> suspendsCounts2 = new HashMap<String, Integer>();    156                    for (ThreadReference threadReference : vm.allThreads()) {    157 suspendsCounts2.put(threadReference.name(), threadReference.suspendCount());
   158                    }
   159                    display(suspendsCounts2.toString());



Reply via email to