8245124: Shenandoah: optimize code root evacuation/update during concurrent class unloading

Reviewed-by: shade

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

@@ -26,6 +26,7 @@
 #include "code/codeCache.hpp"
 #include "code/icBuffer.hpp"
 #include "code/nmethod.hpp"
+#include "gc/shenandoah/shenandoahClosures.inline.hpp"
 #include "gc/shenandoah/shenandoahCodeRoots.hpp"
 #include "gc/shenandoah/shenandoahEvacOOMHandler.hpp"
 #include "gc/shenandoah/shenandoahHeap.inline.hpp"
@@ -272,7 +273,8 @@ public:
 
     // Heal oops and disarm
     if (_bs->is_armed(nm)) {
-      ShenandoahNMethod::heal_nmethod(nm);
+      ShenandoahEvacOOMScope oom_evac_scope;
+      ShenandoahNMethod::heal_nmethod_metadata(nm_data);
       _bs->disarm(nm);
     }
 

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

@@ -110,24 +110,6 @@ void ShenandoahNMethod::update() {
   assert_same_oops();
 }
 
-void ShenandoahNMethod::oops_do(OopClosure* oops, bool fix_relocations) {
-  for (int c = 0; c < _oops_count; c ++) {
-    oops->do_oop(_oops[c]);
-  }
-
-  oop* const begin = _nm->oops_begin();
-  oop* const end = _nm->oops_end();
-  for (oop* p = begin; p < end; p++) {
-    if (*p != Universe::non_oop_word()) {
-      oops->do_oop(p);
-    }
-  }
-
-  if (fix_relocations && _has_non_immed_oops) {
-    _nm->fix_oop_relocations();
-  }
-}
-
 void ShenandoahNMethod::detect_reloc_oops(nmethod* nm, GrowableArray<oop*>& oops, bool& has_non_immed_oops) {
   has_non_immed_oops = false;
   // Find all oops relocations
@@ -215,8 +197,7 @@ void ShenandoahNMethod::heal_nmethod(nmethod* nm) {
     }
   } else if (heap->is_concurrent_weak_root_in_progress()) {
     ShenandoahEvacOOMScope evac_scope;
-    ShenandoahEvacuateUpdateRootsClosure<> cl;
-    data->oops_do(&cl, true /*fix relocation*/);
+    heal_nmethod_metadata(data);
   } else {
     // There is possibility that GC is cancelled when it arrives final mark.
     // In this case, concurrent root phase is skipped and degenerated GC should be

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

@@ -51,7 +51,7 @@ public:
 
   inline nmethod* nm() const;
   inline ShenandoahReentrantLock* lock();
-  void oops_do(OopClosure* oops, bool fix_relocations = false);
+  inline void oops_do(OopClosure* oops, bool fix_relocations = false);
   // Update oops when the nmethod is re-registered
   void update();
 
@@ -67,6 +67,7 @@ public:
   static inline ShenandoahReentrantLock* lock_for_nmethod(nmethod* nm);
 
   static void heal_nmethod(nmethod* nm);
+  static inline void heal_nmethod_metadata(ShenandoahNMethod* nmethod_data);
   static inline void disarm_nmethod(nmethod* nm);
 
   static inline ShenandoahNMethod* gc_data(nmethod* nm);

src/hotspot/share/gc/shenandoah/shenandoahNMethod.inline.hpp

@@ -54,6 +54,29 @@ bool ShenandoahNMethod::is_unregistered() const {
   return _unregistered;
 }
 
+void ShenandoahNMethod::oops_do(OopClosure* oops, bool fix_relocations) {
+  for (int c = 0; c < _oops_count; c ++) {
+    oops->do_oop(_oops[c]);
+  }
+
+  oop* const begin = _nm->oops_begin();
+  oop* const end = _nm->oops_end();
+  for (oop* p = begin; p < end; p++) {
+    if (*p != Universe::non_oop_word()) {
+      oops->do_oop(p);
+    }
+  }
+
+  if (fix_relocations && _has_non_immed_oops) {
+    _nm->fix_oop_relocations();
+  }
+}
+
+void ShenandoahNMethod::heal_nmethod_metadata(ShenandoahNMethod* nmethod_data) {
+  ShenandoahEvacuateUpdateRootsClosure<> cl;
+  nmethod_data->oops_do(&cl, true /*fix relocation*/);
+}
+
 void ShenandoahNMethod::disarm_nmethod(nmethod* nm) {
   if (!ShenandoahConcurrentRoots::can_do_concurrent_class_unloading()) {
     return;