# HG changeset patch
# User rkennke
# Date 1553019479 -3600
#      Tue Mar 19 19:17:59 2019 +0100
# Node ID acc6e0a687c4c4e3d25fac7f179b9cdda5fe4d88
# Parent  7a9a828195c769181646a6e611eea32d46763fb2
8221086: Shenandoah-specific workaround for JDK-8220671

diff --git a/src/hotspot/share/gc/shenandoah/shenandoahBarrierSet.cpp b/src/hotspot/share/gc/shenandoah/shenandoahBarrierSet.cpp
--- a/src/hotspot/share/gc/shenandoah/shenandoahBarrierSet.cpp
+++ b/src/hotspot/share/gc/shenandoah/shenandoahBarrierSet.cpp
@@ -332,6 +332,9 @@
 void ShenandoahBarrierSet::on_thread_attach(Thread *thread) {
   assert(!thread->is_Java_thread() || !SafepointSynchronize::is_at_safepoint(),
          "We should not be at a safepoint");
+  SuspendibleThreadSetJoiner sts(!thread->is_Java_thread() && // Already syncs with safepoints
+                                 !thread->is_VM_thread() &&   // Drives the safepoint itself
+                                 !thread->is_Worker_thread());// Might block if used at SP, syncs otherwise
   SATBMarkQueue& queue = ShenandoahThreadLocalData::satb_mark_queue(thread);
   assert(!queue.is_active(), "SATB queue should not be active");
   assert( queue.is_empty(),  "SATB queue should be empty");
@@ -343,6 +346,9 @@
 }
 
 void ShenandoahBarrierSet::on_thread_detach(Thread *thread) {
+  SuspendibleThreadSetJoiner sts(!thread->is_Java_thread() && // Already syncs with safepoints
+                                 !thread->is_VM_thread() &&   // Drives the safepoint itself
+                                 !thread->is_Worker_thread());// Might block if used at SP, syncs otherwise
   SATBMarkQueue& queue = ShenandoahThreadLocalData::satb_mark_queue(thread);
   queue.flush();
   if (thread->is_Java_thread()) {