On Thu, 4 Aug 2022 10:57:53 GMT, Peter Levart <plev...@openjdk.org> wrote:
> This is an attempt to fix inconsistent behavior of TerminatingThreadLocal(s) > when used internally in JDK for per-carrier-thread caches of native > ByteBuffer(s) and NativeBuffer(s). If used from virtual thread, such > TerminatingThreadLocal(s) are not registered with the carrier thread for the > cleanup. > The fix introduces an internal CarrierThreadLocal subclass of ThreadLocal > which rewires its API methods to use current thread's carrier thread as the > source of ThreadLocalMap instead of current thread itself (if it is a > VirtualThread for example). TerminatingThreadLocal is now a subclass of > CarrierThreadLocal. It seems only per-carrier-thread caching is a usecase for > it. The uses of JavaLangAccess in various places to access a carrier-thread > value of given ThreadLocal has been replaced by public API calls and the use > of CarrierThreadLocal instead of plain ThreadLocal. JavaLangAccess is still > used to dispatch the CarrierThreadLocal API methods, but only for that. Would > someone be tempted to use JavaLangAccess methods directly, they now require > CarrierThreadLocal argument to guard against missuses. > The REGISTRY of TerminatingThreadLocal(s) that tracks which of them have > values bound to a particular carrier thread is now implemented conveniently > with a CarrierThreadLocal. > The test is expanded with a case that demonstrates a situation where a > carrier thread is terminated. Since it must wait for 30 seconds for that to > happen, only one of the test cases is performed in this mode. The correct > logic of TerminatingThreadLocal is still verified with all test-cases using > platform threads that can be terminated more rapidly. This pull request has now been integrated. Changeset: 861cc671 Author: Peter Levart <plev...@openjdk.org> URL: https://git.openjdk.org/jdk/commit/861cc671e2e4904d94f50710be99a511e2f9bb68 Stats: 262 lines in 9 files changed: 196 ins; 12 del; 54 mod 8291897: TerminatingThreadLocal(s) not registered from virtual thread(s) Reviewed-by: alanb ------------- PR: https://git.openjdk.org/jdk/pull/9743
