perf_hooks: avoid memory leak on gc observer

jasnell · rvagg · commit f570c19c8971 · 2018-08-15T20:23:17.000+10:00
Fixes: nodejs/node#22229 PR-URL: nodejs/node#22241 Reviewed-By: Anna Henningsen <anna@addaleax.net> Reviewed-By: Colin Ihrig <cjihrig@gmail.com> Reviewed-By: Yang Guo <yangguo@chromium.org> Reviewed-By: George Adams <george.adams@uk.ibm.com>
diff --git a/src/node_perf.cc b/src/node_perf.cc
@@ -272,6 +272,9 @@ void MarkGarbageCollectionEnd(Isolate* isolate,
                               v8::GCCallbackFlags flags,
                               void* data) {
   Environment* env = static_cast<Environment*>(data);
+  // If no one is listening to gc performance entries, do not create them.
+  if (!env->performance_state()->observers[NODE_PERFORMANCE_ENTRY_TYPE_GC])
+    return;
   GCPerformanceEntry* entry =
       new GCPerformanceEntry(env,
                              static_cast<PerformanceGCKind>(type),
