fix TrackingScheduledExecutor CME seen with testMultiTopologyPollWithError() Jenkins #118
Project: http://git-wip-us.apache.org/repos/asf/incubator-edgent/repo Commit: http://git-wip-us.apache.org/repos/asf/incubator-edgent/commit/d50be305 Tree: http://git-wip-us.apache.org/repos/asf/incubator-edgent/tree/d50be305 Diff: http://git-wip-us.apache.org/repos/asf/incubator-edgent/diff/d50be305 Branch: refs/heads/develop Commit: d50be305b178132cb7b546d600d9b58c48d069d0 Parents: bab6c94 Author: Dale LaBossiere <dlab...@us.ibm.com> Authored: Wed Oct 25 09:55:21 2017 -0400 Committer: Dale LaBossiere <dlab...@us.ibm.com> Committed: Wed Oct 25 09:55:21 2017 -0400 ---------------------------------------------------------------------- .../edgent/runtime/etiao/TrackingScheduledExecutor.java | 12 ++++++++++-- 1 file changed, 10 insertions(+), 2 deletions(-) ---------------------------------------------------------------------- http://git-wip-us.apache.org/repos/asf/incubator-edgent/blob/d50be305/runtime/etiao/src/main/java/org/apache/edgent/runtime/etiao/TrackingScheduledExecutor.java ---------------------------------------------------------------------- diff --git a/runtime/etiao/src/main/java/org/apache/edgent/runtime/etiao/TrackingScheduledExecutor.java b/runtime/etiao/src/main/java/org/apache/edgent/runtime/etiao/TrackingScheduledExecutor.java index c4dc44d..478e419 100644 --- a/runtime/etiao/src/main/java/org/apache/edgent/runtime/etiao/TrackingScheduledExecutor.java +++ b/runtime/etiao/src/main/java/org/apache/edgent/runtime/etiao/TrackingScheduledExecutor.java @@ -118,6 +118,14 @@ public final class TrackingScheduledExecutor extends ScheduledThreadPoolExecutor private int cancelAllAsyncTasks(boolean mayInterruptIfRunning) { int notCanceled = 0; synchronized (asyncTasks) { + // hmm have gotten CMEs here with testMultiTopologyPollWithError. + // This seems to follow the required access pattern for synchronized collection iterator. + // But obviously something's amiss. There seem to be only a few other + // asyncTasks modifiers: + // trackTask() - add + // hasActiveTasks() - iterates while synchronized and can remove + // removeTrack() - remove + // Just to make things iron clad, synch the add and remove too for (RunnableScheduledFuture<?> task : asyncTasks) { if (!task.cancel(mayInterruptIfRunning)) notCanceled++; @@ -134,7 +142,7 @@ public final class TrackingScheduledExecutor extends ScheduledThreadPoolExecutor */ private <V> RunnableScheduledFuture<V> trackTask(RunnableScheduledFuture<V> task) { task = new TrackedFuture<V>(task); - asyncTasks.add(task); + synchronized(asyncTasks) { asyncTasks.add(task); } // see cancelAllAsyncTasks return task; } @@ -214,7 +222,7 @@ public final class TrackingScheduledExecutor extends ScheduledThreadPoolExecutor * the scheduler seems to have no work. */ private void removeTrack() { - asyncTasks.remove(this); + synchronized(asyncTasks) { asyncTasks.remove(this); } // see cancelAllAsyncTasks // Notify the completer if the following is true: // no asyncTasks (user tasks) pending, or the executor's task
