8255036: Shenandoah: Reset GC state for root verifier

Reviewed-by: rkennke

src/hotspot/share/gc/shenandoah/shenandoahRootVerifier.cpp

@@ -40,6 +40,18 @@
 #include "runtime/thread.hpp"
 #include "utilities/debug.hpp"
 
+ShenandoahGCStateResetter::ShenandoahGCStateResetter() :
+  _gc_state(ShenandoahHeap::heap()->gc_state()),
+  _concurrent_weak_root_in_progress(ShenandoahHeap::heap()->is_concurrent_weak_root_in_progress()) {
+}
+
+ShenandoahGCStateResetter::~ShenandoahGCStateResetter() {
+  ShenandoahHeap* const heap = ShenandoahHeap::heap();
+  heap->_gc_state.set(_gc_state);
+  assert(heap->gc_state() == _gc_state, "Should be restored");
+  heap->set_concurrent_weak_root_in_progress(_concurrent_weak_root_in_progress);
+}
+
 // Check for overflow of number of root types.
 STATIC_ASSERT((static_cast<uint>(ShenandoahRootVerifier::AllRoots) + 1) > static_cast<uint>(ShenandoahRootVerifier::AllRoots));
 
@@ -60,6 +72,8 @@ ShenandoahRootVerifier::RootTypes ShenandoahRootVerifier::combine(RootTypes t1,
 }
 
 void ShenandoahRootVerifier::oops_do(OopClosure* oops) {
+  ShenandoahGCStateResetter resetter;
+
   CodeBlobToOopClosure blobs(oops, !CodeBlobToOopClosure::FixRelocations);
   if (verify(CodeRoots)) {
     shenandoah_assert_locked_or_safepoint(CodeCache_lock);
@@ -108,6 +122,7 @@ void ShenandoahRootVerifier::oops_do(OopClosure* oops) {
 }
 
 void ShenandoahRootVerifier::roots_do(OopClosure* oops) {
+  ShenandoahGCStateResetter resetter;
   shenandoah_assert_safepoint();
 
   CodeBlobToOopClosure blobs(oops, !CodeBlobToOopClosure::FixRelocations);
@@ -133,6 +148,7 @@ void ShenandoahRootVerifier::roots_do(OopClosure* oops) {
 }
 
 void ShenandoahRootVerifier::strong_roots_do(OopClosure* oops) {
+  ShenandoahGCStateResetter resetter;
   shenandoah_assert_safepoint();
 
   CodeBlobToOopClosure blobs(oops, !CodeBlobToOopClosure::FixRelocations);

src/hotspot/share/gc/shenandoah/shenandoahRootVerifier.hpp

@@ -28,6 +28,16 @@
 #include "memory/allocation.hpp"
 #include "memory/iterator.hpp"
 
+class ShenandoahGCStateResetter : public StackObj {
+private:
+  const char _gc_state;
+  const bool _concurrent_weak_root_in_progress;
+
+public:
+  ShenandoahGCStateResetter();
+  ~ShenandoahGCStateResetter();
+};
+
 class ShenandoahRootVerifier : public StackObj {
 public:
   enum RootTypes {

src/hotspot/share/gc/shenandoah/shenandoahVerifier.cpp

@@ -592,23 +592,6 @@ public:
   }
 };
 
-class ShenandoahGCStateResetter : public StackObj {
-private:
-  ShenandoahHeap* const _heap;
-  char _gc_state;
-
-public:
-  ShenandoahGCStateResetter() : _heap(ShenandoahHeap::heap()) {
-    _gc_state = _heap->gc_state();
-    _heap->_gc_state.clear();
-  }
-
-  ~ShenandoahGCStateResetter() {
-    _heap->_gc_state.set(_gc_state);
-    assert(_heap->gc_state() == _gc_state, "Should be restored");
-  }
-};
-
 void ShenandoahVerifier::verify_at_safepoint(const char *label,
                                              VerifyForwarded forwarded, VerifyMarked marked,
                                              VerifyCollectionSet cset,