On Wed, 25 Nov 2020 18:40:49 GMT, Coleen Phillimore <cole...@openjdk.org> wrote:
> The ServiceThread cleaning used a stale ObjectFree state when calling
> remove_dead_entries, because another thread had concurrently set is_enabled
> to false. Add a lock around setting/resetting the lock event state and
> retest the state under a lock. Ran the test 100s of time without failure,
> where otherwise it fails very quickly.
> Tested with tier2,3 and running tiers 4,5,6 in progress.
> Thanks to Kim for his previous feedback.
src/hotspot/share/prims/jvmtiTagMap.cpp line 1162:
> 1160: if (_needs_cleaning) {
> 1161: // Recheck whether to post object free events under the lock.
> 1162: post_object_free = post_object_free &&
> env()->is_enabled(JVMTI_EVENT_OBJECT_FREE);
Where is `is_enabled` called without the lock being held in a caller of
`remove_dead_entries()`?
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PR: https://git.openjdk.java.net/jdk/pull/1439
