From 8ccf5296956b0c6a37e52ff429943d3f2f1ccee3 Mon Sep 17 00:00:00 2001
From: Aleksey Shipilev <shade@redhat.com>
Date: Fri, 25 Jun 2021 14:34:02 +0200
Subject: [PATCH] 8267396: Avoid recording "pc" in unhandled oops detector for
 better performance

Reviewed-by: coleenp, dholmes
---
 src/hotspot/share/oops/oopsHierarchy.cpp    | 3 +--
 src/hotspot/share/runtime/unhandledOops.cpp | 7 +++----
 src/hotspot/share/runtime/unhandledOops.hpp | 9 ++++-----
 3 files changed, 8 insertions(+), 11 deletions(-)

diff --git a/src/hotspot/share/oops/oopsHierarchy.cpp b/src/hotspot/share/oops/oopsHierarchy.cpp
index 5c56d01d43b..2648052d78f 100644
--- a/src/hotspot/share/oops/oopsHierarchy.cpp
+++ b/src/hotspot/share/oops/oopsHierarchy.cpp
@@ -37,8 +37,7 @@ void oop::register_oop() {
   // This gets expensive, which is why checking unhandled oops is on a switch.
   Thread* t = Thread::current_or_null();
   if (t != NULL && t->is_Java_thread()) {
-     frame fr = os::current_frame();
-     t->unhandled_oops()->register_unhandled_oop(this, fr.pc());
+     t->unhandled_oops()->register_unhandled_oop(this);
   }
 }
 
diff --git a/src/hotspot/share/runtime/unhandledOops.cpp b/src/hotspot/share/runtime/unhandledOops.cpp
index ef30c6e4c0d..8d1bc74adeb 100644
--- a/src/hotspot/share/runtime/unhandledOops.cpp
+++ b/src/hotspot/share/runtime/unhandledOops.cpp
@@ -58,7 +58,7 @@ void UnhandledOops::dump_oops(UnhandledOops *list) {
 // You don't want to turn it on in compiled code here.
 static bool unhandled_oop_print=0;
 
-void UnhandledOops::register_unhandled_oop(oop* op, address pc) {
+void UnhandledOops::register_unhandled_oop(oop* op) {
   if (!_thread->is_in_stack((address)op))
     return;
 
@@ -67,7 +67,7 @@ void UnhandledOops::register_unhandled_oop(oop* op, address pc) {
     for (int i=0; i<_level; i++) tty->print(" ");
     tty->print_cr("r " INTPTR_FORMAT, p2i(op));
   }
-  UnhandledOopEntry entry(op, pc);
+  UnhandledOopEntry entry(op);
   _oop_list->push(entry);
 }
 
@@ -120,8 +120,7 @@ void UnhandledOops::clear_unhandled_oops() {
     // in the unhandled oop generator.
     if(!_thread->is_in_stack((address)entry._oop_ptr)) {
       tty->print_cr("oop_ptr is " INTPTR_FORMAT, p2i(entry._oop_ptr));
-      tty->print_cr("thread is " INTPTR_FORMAT " from pc " INTPTR_FORMAT,
-                     p2i(_thread), p2i(entry._pc));
+      tty->print_cr("thread is " INTPTR_FORMAT, p2i(_thread));
       assert(false, "heap is corrupted by the unhandled oop detector");
     }
     // Set unhandled oops to a pattern that will crash distinctively
diff --git a/src/hotspot/share/runtime/unhandledOops.hpp b/src/hotspot/share/runtime/unhandledOops.hpp
index 73572646706..942a602f294 100644
--- a/src/hotspot/share/runtime/unhandledOops.hpp
+++ b/src/hotspot/share/runtime/unhandledOops.hpp
@@ -53,12 +53,11 @@ class UnhandledOopEntry : public CHeapObj<mtThread> {
  private:
   oop* _oop_ptr;
   bool _ok_for_gc;
-  address _pc;
  public:
   oop* oop_ptr() { return _oop_ptr; }
-  UnhandledOopEntry() : _oop_ptr(NULL), _ok_for_gc(false), _pc(NULL) {}
-  UnhandledOopEntry(oop* op, address pc) :
-                        _oop_ptr(op),   _ok_for_gc(false), _pc(pc) {}
+  UnhandledOopEntry() : _oop_ptr(NULL), _ok_for_gc(false) {}
+  UnhandledOopEntry(oop* op) :
+                        _oop_ptr(op),   _ok_for_gc(false) {}
 };
 
 
@@ -75,7 +74,7 @@ class UnhandledOops : public CHeapObj<mtThread> {
 
  public:
   static void dump_oops(UnhandledOops* list);
-  void register_unhandled_oop(oop* op, address pc);
+  void register_unhandled_oop(oop* op);
   void unregister_unhandled_oop(oop* op);
 };