8333290: NMT report should not print Metaspace info if Metaspace is not yet initialized

Reviewed-by: stefank, dholmes

src/hotspot/share/memory/metaspace/runningCounters.cpp

@@ -45,6 +45,7 @@ size_t RunningCounters::reserved_words_class() {
 }
 
 size_t RunningCounters::reserved_words_nonclass() {
+  assert(VirtualSpaceList::vslist_nonclass() != nullptr, "Metaspace not yet initialized");
   return VirtualSpaceList::vslist_nonclass()->reserved_words();
 }
 
@@ -59,6 +60,7 @@ size_t RunningCounters::committed_words_class() {
 }
 
 size_t RunningCounters::committed_words_nonclass() {
+  assert(VirtualSpaceList::vslist_nonclass() != nullptr, "Metaspace not yet initialized");
   return VirtualSpaceList::vslist_nonclass()->committed_words();
 }
 
@@ -90,6 +92,7 @@ size_t RunningCounters::free_chunks_words_class() {
 }
 
 size_t RunningCounters::free_chunks_words_nonclass() {
+  assert(ChunkManager::chunkmanager_nonclass() != nullptr, "Metaspace not yet initialized");
   return ChunkManager::chunkmanager_nonclass()->total_word_size();
 }
 

src/hotspot/share/nmt/memReporter.cpp

@@ -272,6 +272,13 @@ void MemSummaryReporter::report_summary_of_type(MEMFLAGS flag,
 }
 
 void MemSummaryReporter::report_metadata(Metaspace::MetadataType type) const {
+
+  // NMT reports may be triggered (as part of error handling) very early. Make sure
+  // Metaspace is already initialized.
+  if (!Metaspace::initialized()) {
+    return;
+  }
+
   assert(type == Metaspace::NonClassType || type == Metaspace::ClassType,
     "Invalid metadata type");
   const char* name = (type == Metaspace::NonClassType) ?