changeset 53894:bf1133e7dfba

8219469: ZGC: Extract functions out from ZNMethodTable into new ZNMethod class Reviewed-by: pliden
author stefank
date Thu, 21 Feb 2019 14:24:44 +0100
parents ad56513c7e07
children b22d8ae270a2
files src/hotspot/share/gc/z/zBarrierSetNMethod.cpp src/hotspot/share/gc/z/zCollectedHeap.cpp src/hotspot/share/gc/z/zNMethod.cpp src/hotspot/share/gc/z/zNMethod.hpp src/hotspot/share/gc/z/zNMethodTable.cpp src/hotspot/share/gc/z/zNMethodTable.hpp src/hotspot/share/gc/z/zRootsIterator.cpp src/hotspot/share/gc/z/zUnload.cpp
diffstat 8 files changed, 474 insertions(+), 367 deletions(-) [+]
line wrap: on
line diff
--- a/src/hotspot/share/gc/z/zBarrierSetNMethod.cpp	Wed Feb 20 12:04:12 2019 +0100
+++ b/src/hotspot/share/gc/z/zBarrierSetNMethod.cpp	Thu Feb 21 14:24:44 2019 +0100
@@ -27,12 +27,12 @@
 #include "gc/z/zGlobals.hpp"
 #include "gc/z/zLock.inline.hpp"
 #include "gc/z/zOopClosures.hpp"
-#include "gc/z/zNMethodTable.hpp"
+#include "gc/z/zNMethod.hpp"
 #include "gc/z/zThreadLocalData.hpp"
 #include "logging/log.hpp"
 
 bool ZBarrierSetNMethod::nmethod_entry_barrier(nmethod* nm) {
-  ZLocker<ZReentrantLock> locker(ZNMethodTable::lock_for_nmethod(nm));
+  ZLocker<ZReentrantLock> locker(ZNMethod::lock_for_nmethod(nm));
   log_trace(nmethod, barrier)("Entered critical zone for %p", nm);
 
   if (!is_armed(nm)) {
--- a/src/hotspot/share/gc/z/zCollectedHeap.cpp	Wed Feb 20 12:04:12 2019 +0100
+++ b/src/hotspot/share/gc/z/zCollectedHeap.cpp	Thu Feb 21 14:24:44 2019 +0100
@@ -27,7 +27,7 @@
 #include "gc/z/zCollectedHeap.hpp"
 #include "gc/z/zGlobals.hpp"
 #include "gc/z/zHeap.inline.hpp"
-#include "gc/z/zNMethodTable.hpp"
+#include "gc/z/zNMethod.hpp"
 #include "gc/z/zServiceability.hpp"
 #include "gc/z/zStat.hpp"
 #include "gc/z/zUtils.inline.hpp"
@@ -255,11 +255,11 @@
 }
 
 void ZCollectedHeap::register_nmethod(nmethod* nm) {
-  ZNMethodTable::register_nmethod(nm);
+  ZNMethod::register_nmethod(nm);
 }
 
 void ZCollectedHeap::unregister_nmethod(nmethod* nm) {
-  ZNMethodTable::unregister_nmethod(nm);
+  ZNMethod::unregister_nmethod(nm);
 }
 
 void ZCollectedHeap::verify_nmethod(nmethod* nm) {
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/src/hotspot/share/gc/z/zNMethod.cpp	Thu Feb 21 14:24:44 2019 +0100
@@ -0,0 +1,394 @@
+/*
+ * Copyright (c) 2017, 2018, Oracle and/or its affiliates. All rights reserved.
+ * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
+ *
+ * This code is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 only, as
+ * published by the Free Software Foundation.
+ *
+ * This code is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
+ * version 2 for more details (a copy is included in the LICENSE file that
+ * accompanied this code).
+ *
+ * You should have received a copy of the GNU General Public License version
+ * 2 along with this work; if not, write to the Free Software Foundation,
+ * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
+ *
+ * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
+ * or visit www.oracle.com if you need additional information or have any
+ * questions.
+ */
+
+#include "precompiled.hpp"
+#include "code/relocInfo.hpp"
+#include "code/nmethod.hpp"
+#include "code/icBuffer.hpp"
+#include "gc/shared/barrierSet.hpp"
+#include "gc/shared/barrierSetNMethod.hpp"
+#include "gc/z/zGlobals.hpp"
+#include "gc/z/zLock.inline.hpp"
+#include "gc/z/zNMethod.hpp"
+#include "gc/z/zNMethodData.hpp"
+#include "gc/z/zNMethodTable.hpp"
+#include "gc/z/zOopClosures.inline.hpp"
+#include "gc/z/zTask.hpp"
+#include "gc/z/zWorkers.hpp"
+#include "logging/log.hpp"
+#include "memory/allocation.inline.hpp"
+#include "memory/iterator.hpp"
+#include "memory/resourceArea.hpp"
+#include "runtime/atomic.hpp"
+#include "runtime/orderAccess.hpp"
+#include "utilities/debug.hpp"
+
+static ZNMethodData* gc_data(const nmethod* nm) {
+  return nm->gc_data<ZNMethodData>();
+}
+
+static void set_gc_data(nmethod* nm, ZNMethodData* data) {
+  return nm->set_gc_data<ZNMethodData>(data);
+}
+
+void ZNMethod::attach_gc_data(nmethod* nm) {
+  GrowableArray<oop*> immediate_oops;
+  bool non_immediate_oops = false;
+
+  // Find all oops relocations
+  RelocIterator iter(nm);
+  while (iter.next()) {
+    if (iter.type() != relocInfo::oop_type) {
+      // Not an oop
+      continue;
+    }
+
+    oop_Relocation* r = iter.oop_reloc();
+
+    if (!r->oop_is_immediate()) {
+      // Non-immediate oop found
+      non_immediate_oops = true;
+      continue;
+    }
+
+    if (r->oop_value() != NULL) {
+      // Non-NULL immediate oop found. NULL oops can safely be
+      // ignored since the method will be re-registered if they
+      // are later patched to be non-NULL.
+      immediate_oops.push(r->oop_addr());
+    }
+  }
+
+  // Attach GC data to nmethod
+  ZNMethodData* data = gc_data(nm);
+  if (data == NULL) {
+    data = ZNMethodData::create(nm);
+    set_gc_data(nm, data);
+  }
+
+  // Attach oops in GC data
+  ZNMethodDataOops* const new_oops = ZNMethodDataOops::create(immediate_oops, non_immediate_oops);
+  ZNMethodDataOops* const old_oops = data->swap_oops(new_oops);
+  ZNMethodDataOops::destroy(old_oops);
+}
+
+void ZNMethod::detach_gc_data(nmethod* nm) {
+  // Destroy GC data
+  ZNMethodData::destroy(gc_data(nm));
+  set_gc_data(nm, NULL);
+}
+
+ZReentrantLock* ZNMethod::lock_for_nmethod(nmethod* nm) {
+  ZNMethodData* const data = gc_data(nm);
+  if (data == NULL) {
+    return NULL;
+  }
+  return data->lock();
+}
+
+void ZNMethod::log_register(const nmethod* nm) {
+  LogTarget(Trace, gc, nmethod) log;
+  if (!log.is_enabled()) {
+    return;
+  }
+
+  const ZNMethodDataOops* const oops = gc_data(nm)->oops();
+
+  log.print("Register NMethod: %s.%s (" PTR_FORMAT "), "
+            "Compiler: %s, Oops: %d, ImmediateOops: " SIZE_FORMAT ", NonImmediateOops: %s",
+            nm->method()->method_holder()->external_name(),
+            nm->method()->name()->as_C_string(),
+            p2i(nm),
+            nm->compiler_name(),
+            nm->oops_count() - 1,
+            oops->immediates_count(),
+            oops->has_non_immediates() ? "Yes" : "No");
+
+  LogTarget(Trace, gc, nmethod, oops) log_oops;
+  if (!log_oops.is_enabled()) {
+    return;
+  }
+
+  // Print nmethod oops table
+  {
+    oop* const begin = nm->oops_begin();
+    oop* const end = nm->oops_end();
+    for (oop* p = begin; p < end; p++) {
+      log_oops.print("           Oop[" SIZE_FORMAT "] " PTR_FORMAT " (%s)",
+                     (p - begin), p2i(*p), (*p)->klass()->external_name());
+    }
+  }
+
+  // Print nmethod immediate oops
+  {
+    oop** const begin = oops->immediates_begin();
+    oop** const end = oops->immediates_end();
+    for (oop** p = begin; p < end; p++) {
+      log_oops.print("  ImmediateOop[" SIZE_FORMAT "] " PTR_FORMAT " @ " PTR_FORMAT " (%s)",
+                     (p - begin), p2i(**p), p2i(*p), (**p)->klass()->external_name());
+    }
+  }
+}
+
+void ZNMethod::log_unregister(const nmethod* nm) {
+  LogTarget(Debug, gc, nmethod) log;
+  if (!log.is_enabled()) {
+    return;
+  }
+
+  log.print("Unregister NMethod: %s.%s (" PTR_FORMAT ")",
+            nm->method()->method_holder()->external_name(),
+            nm->method()->name()->as_C_string(),
+            p2i(nm));
+}
+
+void ZNMethod::register_nmethod(nmethod* nm) {
+  ResourceMark rm;
+
+  // Create and attach gc data
+  attach_gc_data(nm);
+
+  log_register(nm);
+
+  ZNMethodTable::register_nmethod(nm);
+
+  // Disarm nmethod entry barrier
+  disarm_nmethod(nm);
+}
+
+void ZNMethod::unregister_nmethod(nmethod* nm) {
+  assert(CodeCache_lock->owned_by_self(), "Lock must be held");
+
+  if (Thread::current()->is_Code_cache_sweeper_thread()) {
+    // The sweeper must wait for any ongoing iteration to complete
+    // before it can unregister an nmethod.
+    ZNMethodTable::wait_until_iteration_done();
+  }
+
+  ResourceMark rm;
+
+  log_unregister(nm);
+
+  ZNMethodTable::unregister_nmethod(nm);
+
+  // Destroy and detach gc data
+  detach_gc_data(nm);
+}
+
+void ZNMethod::disarm_nmethod(nmethod* nm) {
+  BarrierSetNMethod* const bs = BarrierSet::barrier_set()->barrier_set_nmethod();
+  if (bs != NULL) {
+    bs->disarm(nm);
+  }
+}
+
+void ZNMethod::nmethod_oops_do(nmethod* nm, OopClosure* cl) {
+  // Process oops table
+  {
+    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()) {
+        cl->do_oop(p);
+      }
+    }
+  }
+
+  ZNMethodDataOops* const oops = gc_data(nm)->oops();
+
+  // Process immediate oops
+  {
+    oop** const begin = oops->immediates_begin();
+    oop** const end = oops->immediates_end();
+    for (oop** p = begin; p < end; p++) {
+      if (**p != Universe::non_oop_word()) {
+        cl->do_oop(*p);
+      }
+    }
+  }
+
+  // Process non-immediate oops
+  if (oops->has_non_immediates()) {
+    nm->fix_oop_relocations();
+  }
+}
+
+class ZNMethodToOopsDoClosure : public NMethodClosure {
+private:
+  OopClosure* _cl;
+
+public:
+  ZNMethodToOopsDoClosure(OopClosure* cl) :
+      _cl(cl) {}
+
+  virtual void do_nmethod(nmethod* nm) {
+    ZNMethod::nmethod_oops_do(nm, _cl);
+  }
+};
+
+void ZNMethod::oops_do_begin() {
+  ZNMethodTable::nmethods_do_begin();
+}
+
+void ZNMethod::oops_do_end() {
+  ZNMethodTable::nmethods_do_end();
+}
+
+void ZNMethod::oops_do(OopClosure* cl) {
+  ZNMethodToOopsDoClosure nmethod_cl(cl);
+  ZNMethodTable::nmethods_do(&nmethod_cl);
+}
+
+class ZNMethodUnlinkClosure : public NMethodClosure {
+private:
+  bool          _unloading_occurred;
+  volatile bool _failed;
+
+  void set_failed() {
+    Atomic::store(true, &_failed);
+  }
+
+public:
+  ZNMethodUnlinkClosure(bool unloading_occurred) :
+      _unloading_occurred(unloading_occurred),
+      _failed(false) {}
+
+  virtual void do_nmethod(nmethod* nm) {
+    if (failed()) {
+      return;
+    }
+
+    if (!nm->is_alive()) {
+      return;
+    }
+
+    ZLocker<ZReentrantLock> locker(ZNMethod::lock_for_nmethod(nm));
+
+    if (nm->is_unloading()) {
+      // Unlinking of the dependencies must happen before the
+      // handshake separating unlink and purge.
+      nm->flush_dependencies(false /* delete_immediately */);
+
+      // We don't need to take the lock when unlinking nmethods from
+      // the Method, because it is only concurrently unlinked by
+      // the entry barrier, which acquires the per nmethod lock.
+      nm->unlink_from_method(false /* acquire_lock */);
+      return;
+    }
+
+    // Heal oops and disarm
+    ZNMethodOopClosure cl;
+    ZNMethod::nmethod_oops_do(nm, &cl);
+    ZNMethod::disarm_nmethod(nm);
+
+    // Clear compiled ICs and exception caches
+    if (!nm->unload_nmethod_caches(_unloading_occurred)) {
+      set_failed();
+    }
+  }
+
+  bool failed() const {
+    return Atomic::load(&_failed);
+  }
+};
+
+class ZNMethodUnlinkTask : public ZTask {
+private:
+  ZNMethodUnlinkClosure _cl;
+  ICRefillVerifier*     _verifier;
+
+public:
+  ZNMethodUnlinkTask(bool unloading_occurred, ICRefillVerifier* verifier) :
+      ZTask("ZNMethodUnlinkTask"),
+      _cl(unloading_occurred),
+      _verifier(verifier) {
+    ZNMethodTable::nmethods_do_begin();
+  }
+
+  ~ZNMethodUnlinkTask() {
+    ZNMethodTable::nmethods_do_end();
+  }
+
+  virtual void work() {
+    ICRefillVerifierMark mark(_verifier);
+    ZNMethodTable::nmethods_do(&_cl);
+  }
+
+  bool success() const {
+    return !_cl.failed();
+  }
+};
+
+void ZNMethod::unlink(ZWorkers* workers, bool unloading_occurred) {
+  for (;;) {
+    ICRefillVerifier verifier;
+
+    {
+      ZNMethodUnlinkTask task(unloading_occurred, &verifier);
+      workers->run_concurrent(&task);
+      if (task.success()) {
+        return;
+      }
+    }
+
+    // Cleaning failed because we ran out of transitional IC stubs,
+    // so we have to refill and try again. Refilling requires taking
+    // a safepoint, so we temporarily leave the suspendible thread set.
+    SuspendibleThreadSetLeaver sts;
+    InlineCacheBuffer::refill_ic_stubs();
+  }
+}
+
+class ZNMethodPurgeClosure : public NMethodClosure {
+public:
+  virtual void do_nmethod(nmethod* nm) {
+    if (nm->is_alive() && nm->is_unloading()) {
+      nm->make_unloaded();
+    }
+  }
+};
+
+class ZNMethodPurgeTask : public ZTask {
+private:
+  ZNMethodPurgeClosure _cl;
+
+public:
+  ZNMethodPurgeTask() :
+      ZTask("ZNMethodPurgeTask"),
+      _cl() {
+    ZNMethodTable::nmethods_do_begin();
+  }
+
+  ~ZNMethodPurgeTask() {
+    ZNMethodTable::nmethods_do_end();
+  }
+
+  virtual void work() {
+    ZNMethodTable::nmethods_do(&_cl);
+  }
+};
+
+void ZNMethod::purge(ZWorkers* workers) {
+  ZNMethodPurgeTask task;
+  workers->run_concurrent(&task);
+}
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/src/hotspot/share/gc/z/zNMethod.hpp	Thu Feb 21 14:24:44 2019 +0100
@@ -0,0 +1,60 @@
+/*
+ * Copyright (c) 2017, 2019, Oracle and/or its affiliates. All rights reserved.
+ * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
+ *
+ * This code is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 only, as
+ * published by the Free Software Foundation.
+ *
+ * This code is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
+ * version 2 for more details (a copy is included in the LICENSE file that
+ * accompanied this code).
+ *
+ * You should have received a copy of the GNU General Public License version
+ * 2 along with this work; if not, write to the Free Software Foundation,
+ * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
+ *
+ * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
+ * or visit www.oracle.com if you need additional information or have any
+ * questions.
+ */
+
+#ifndef SHARE_GC_Z_ZNMETHOD_HPP
+#define SHARE_GC_Z_ZNMETHOD_HPP
+
+#include "memory/allocation.hpp"
+
+class nmethod;
+class OopClosure;
+class ZReentrantLock;
+class ZWorkers;
+
+class ZNMethod : public AllStatic {
+private:
+  static void attach_gc_data(nmethod* nm);
+  static void detach_gc_data(nmethod* nm);
+
+  static void log_register(const nmethod* nm);
+  static void log_unregister(const nmethod* nm);
+
+public:
+  static void register_nmethod(nmethod* nm);
+  static void unregister_nmethod(nmethod* nm);
+
+  static void disarm_nmethod(nmethod* nm);
+
+  static void nmethod_oops_do(nmethod* nm, OopClosure* cl);
+
+  static void oops_do_begin();
+  static void oops_do_end();
+  static void oops_do(OopClosure* cl);
+
+  static ZReentrantLock* lock_for_nmethod(nmethod* nm);
+
+  static void unlink(ZWorkers* workers, bool unloading_occurred);
+  static void purge(ZWorkers* workers);
+};
+
+#endif // SHARE_GC_Z_ZNMETHOD_HPP
--- a/src/hotspot/share/gc/z/zNMethodTable.cpp	Wed Feb 20 12:04:12 2019 +0100
+++ b/src/hotspot/share/gc/z/zNMethodTable.cpp	Thu Feb 21 14:24:44 2019 +0100
@@ -33,6 +33,7 @@
 #include "gc/z/zNMethodAllocator.hpp"
 #include "gc/z/zNMethodData.hpp"
 #include "gc/z/zNMethodTable.hpp"
+#include "gc/z/zNMethodTableEntry.hpp"
 #include "gc/z/zNMethodTableIteration.hpp"
 #include "gc/z/zOopClosures.inline.hpp"
 #include "gc/z/zTask.hpp"
@@ -51,14 +52,6 @@
 size_t ZNMethodTable::_nunregistered = 0;
 ZNMethodTableIteration ZNMethodTable::_iteration;
 
-static ZNMethodData* gc_data(const nmethod* nm) {
-  return nm->gc_data<ZNMethodData>();
-}
-
-static void set_gc_data(nmethod* nm, ZNMethodData* data) {
-  return nm->set_gc_data<ZNMethodData>(data);
-}
-
 ZNMethodTableEntry* ZNMethodTable::create(size_t size) {
   void* const mem = ZNMethodAllocator::allocate(size * sizeof(ZNMethodTableEntry));
   return ::new (mem) ZNMethodTableEntry[size];
@@ -68,61 +61,6 @@
   ZNMethodAllocator::free(table);
 }
 
-void ZNMethodTable::attach_gc_data(nmethod* nm) {
-  GrowableArray<oop*> immediate_oops;
-  bool non_immediate_oops = false;
-
-  // Find all oops relocations
-  RelocIterator iter(nm);
-  while (iter.next()) {
-    if (iter.type() != relocInfo::oop_type) {
-      // Not an oop
-      continue;
-    }
-
-    oop_Relocation* r = iter.oop_reloc();
-
-    if (!r->oop_is_immediate()) {
-      // Non-immediate oop found
-      non_immediate_oops = true;
-      continue;
-    }
-
-    if (r->oop_value() != NULL) {
-      // Non-NULL immediate oop found. NULL oops can safely be
-      // ignored since the method will be re-registered if they
-      // are later patched to be non-NULL.
-      immediate_oops.push(r->oop_addr());
-    }
-  }
-
-  // Attach GC data to nmethod
-  ZNMethodData* data = gc_data(nm);
-  if (data == NULL) {
-    data = ZNMethodData::create(nm);
-    set_gc_data(nm, data);
-  }
-
-  // Attach oops in GC data
-  ZNMethodDataOops* const new_oops = ZNMethodDataOops::create(immediate_oops, non_immediate_oops);
-  ZNMethodDataOops* const old_oops = data->swap_oops(new_oops);
-  ZNMethodDataOops::destroy(old_oops);
-}
-
-void ZNMethodTable::detach_gc_data(nmethod* nm) {
-  // Destroy GC data
-  ZNMethodData::destroy(gc_data(nm));
-  set_gc_data(nm, NULL);
-}
-
-ZReentrantLock* ZNMethodTable::lock_for_nmethod(nmethod* nm) {
-  ZNMethodData* const data = gc_data(nm);
-  if (data == NULL) {
-    return NULL;
-  }
-  return data->lock();
-}
-
 size_t ZNMethodTable::first_index(const nmethod* nm, size_t size) {
   assert(is_power_of_2(size), "Invalid size");
   const size_t mask = size - 1;
@@ -238,62 +176,6 @@
   }
 }
 
-void ZNMethodTable::log_register(const nmethod* nm) {
-  LogTarget(Trace, gc, nmethod) log;
-  if (!log.is_enabled()) {
-    return;
-  }
-
-  const ZNMethodDataOops* const oops = gc_data(nm)->oops();
-
-  log.print("Register NMethod: %s.%s (" PTR_FORMAT "), "
-            "Compiler: %s, Oops: %d, ImmediateOops: " SIZE_FORMAT ", NonImmediateOops: %s",
-            nm->method()->method_holder()->external_name(),
-            nm->method()->name()->as_C_string(),
-            p2i(nm),
-            nm->compiler_name(),
-            nm->oops_count() - 1,
-            oops->immediates_count(),
-            oops->has_non_immediates() ? "Yes" : "No");
-
-  LogTarget(Trace, gc, nmethod, oops) log_oops;
-  if (!log_oops.is_enabled()) {
-    return;
-  }
-
-  // Print nmethod oops table
-  {
-    oop* const begin = nm->oops_begin();
-    oop* const end = nm->oops_end();
-    for (oop* p = begin; p < end; p++) {
-      log_oops.print("           Oop[" SIZE_FORMAT "] " PTR_FORMAT " (%s)",
-                     (p - begin), p2i(*p), (*p)->klass()->external_name());
-    }
-  }
-
-  // Print nmethod immediate oops
-  {
-    oop** const begin = oops->immediates_begin();
-    oop** const end = oops->immediates_end();
-    for (oop** p = begin; p < end; p++) {
-      log_oops.print("  ImmediateOop[" SIZE_FORMAT "] " PTR_FORMAT " @ " PTR_FORMAT " (%s)",
-                     (p - begin), p2i(**p), p2i(*p), (**p)->klass()->external_name());
-    }
-  }
-}
-
-void ZNMethodTable::log_unregister(const nmethod* nm) {
-  LogTarget(Debug, gc, nmethod) log;
-  if (!log.is_enabled()) {
-    return;
-  }
-
-  log.print("Unregister NMethod: %s.%s (" PTR_FORMAT ")",
-            nm->method()->method_holder()->external_name(),
-            nm->method()->name()->as_C_string(),
-            p2i(nm));
-}
-
 size_t ZNMethodTable::registered_nmethods() {
   return _nregistered;
 }
@@ -304,16 +186,10 @@
 
 void ZNMethodTable::register_nmethod(nmethod* nm) {
   assert(CodeCache_lock->owned_by_self(), "Lock must be held");
-  ResourceMark rm;
 
   // Grow/Shrink/Prune table if needed
   rebuild_if_needed();
 
-  // Create and attach gc data
-  attach_gc_data(nm);
-
-  log_register(nm);
-
   // Insert new entry
   if (register_entry(_table, _size, nm)) {
     // New entry registered. When register_entry() instead returns
@@ -321,9 +197,6 @@
     // to increase number of registered entries in that case.
     _nregistered++;
   }
-
-  // Disarm nmethod entry barrier
-  disarm_nmethod(nm);
 }
 
 void ZNMethodTable::wait_until_iteration_done() {
@@ -337,29 +210,10 @@
 void ZNMethodTable::unregister_nmethod(nmethod* nm) {
   assert(CodeCache_lock->owned_by_self(), "Lock must be held");
 
-  if (Thread::current()->is_Code_cache_sweeper_thread()) {
-    // The sweeper must wait for any ongoing iteration to complete
-    // before it can unregister an nmethod.
-    ZNMethodTable::wait_until_iteration_done();
-  }
-
-  ResourceMark rm;
-
-  log_unregister(nm);
-
   // Remove entry
   unregister_entry(_table, _size, nm);
   _nunregistered++;
   _nregistered--;
-
-  detach_gc_data(nm);
-}
-
-void ZNMethodTable::disarm_nmethod(nmethod* nm) {
-  BarrierSetNMethod* const bs = BarrierSet::barrier_set()->barrier_set_nmethod();
-  if (bs != NULL) {
-    bs->disarm(nm);
-  }
 }
 
 void ZNMethodTable::nmethods_do_begin() {
@@ -385,189 +239,6 @@
   CodeCache_lock->notify_all();
 }
 
-void ZNMethodTable::oops_do(nmethod* nm, OopClosure* cl) {
-  // Process oops table
-  {
-    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()) {
-        cl->do_oop(p);
-      }
-    }
-  }
-
-  ZNMethodDataOops* const oops = gc_data(nm)->oops();
-
-  // Process immediate oops
-  {
-    oop** const begin = oops->immediates_begin();
-    oop** const end = oops->immediates_end();
-    for (oop** p = begin; p < end; p++) {
-      if (**p != Universe::non_oop_word()) {
-        cl->do_oop(*p);
-      }
-    }
-  }
-
-  // Process non-immediate oops
-  if (oops->has_non_immediates()) {
-    nm->fix_oop_relocations();
-  }
-}
-
-class ZNMethodToOopsDoClosure : public NMethodClosure {
-private:
-  OopClosure* _cl;
-
-public:
-  ZNMethodToOopsDoClosure(OopClosure* cl) :
-      _cl(cl) {}
-
-  virtual void do_nmethod(nmethod* nm) {
-    ZNMethodTable::oops_do(nm, _cl);
-  }
-};
-
-void ZNMethodTable::oops_do(OopClosure* cl) {
-  ZNMethodToOopsDoClosure nm_cl(cl);
-  nmethods_do(&nm_cl);
-}
-
 void ZNMethodTable::nmethods_do(NMethodClosure* cl) {
   _iteration.nmethods_do(cl);
 }
-
-class ZNMethodTableUnlinkClosure : public NMethodClosure {
-private:
-  bool          _unloading_occurred;
-  volatile bool _failed;
-
-  void set_failed() {
-    Atomic::store(true, &_failed);
-  }
-
-public:
-  ZNMethodTableUnlinkClosure(bool unloading_occurred) :
-      _unloading_occurred(unloading_occurred),
-      _failed(false) {}
-
-  virtual void do_nmethod(nmethod* nm) {
-    if (failed()) {
-      return;
-    }
-
-    if (!nm->is_alive()) {
-      return;
-    }
-
-    ZLocker<ZReentrantLock> locker(ZNMethodTable::lock_for_nmethod(nm));
-
-    if (nm->is_unloading()) {
-      // Unlinking of the dependencies must happen before the
-      // handshake separating unlink and purge.
-      nm->flush_dependencies(false /* delete_immediately */);
-
-      // We don't need to take the lock when unlinking nmethods from
-      // the Method, because it is only concurrently unlinked by
-      // the entry barrier, which acquires the per nmethod lock.
-      nm->unlink_from_method(false /* acquire_lock */);
-      return;
-    }
-
-    // Heal oops and disarm
-    ZNMethodOopClosure cl;
-    ZNMethodTable::oops_do(nm, &cl);
-    ZNMethodTable::disarm_nmethod(nm);
-
-    // Clear compiled ICs and exception caches
-    if (!nm->unload_nmethod_caches(_unloading_occurred)) {
-      set_failed();
-    }
-  }
-
-  bool failed() const {
-    return Atomic::load(&_failed);
-  }
-};
-
-class ZNMethodTableUnlinkTask : public ZTask {
-private:
-  ZNMethodTableUnlinkClosure _cl;
-  ICRefillVerifier*          _verifier;
-
-public:
-  ZNMethodTableUnlinkTask(bool unloading_occurred, ICRefillVerifier* verifier) :
-      ZTask("ZNMethodTableUnlinkTask"),
-      _cl(unloading_occurred),
-      _verifier(verifier) {
-    ZNMethodTable::nmethods_do_begin();
-  }
-
-  ~ZNMethodTableUnlinkTask() {
-    ZNMethodTable::nmethods_do_end();
-  }
-
-  virtual void work() {
-    ICRefillVerifierMark mark(_verifier);
-    ZNMethodTable::nmethods_do(&_cl);
-  }
-
-  bool success() const {
-    return !_cl.failed();
-  }
-};
-
-void ZNMethodTable::unlink(ZWorkers* workers, bool unloading_occurred) {
-  for (;;) {
-    ICRefillVerifier verifier;
-
-    {
-      ZNMethodTableUnlinkTask task(unloading_occurred, &verifier);
-      workers->run_concurrent(&task);
-      if (task.success()) {
-        return;
-      }
-    }
-
-    // Cleaning failed because we ran out of transitional IC stubs,
-    // so we have to refill and try again. Refilling requires taking
-    // a safepoint, so we temporarily leave the suspendible thread set.
-    SuspendibleThreadSetLeaver sts;
-    InlineCacheBuffer::refill_ic_stubs();
-  }
-}
-
-class ZNMethodTablePurgeClosure : public NMethodClosure {
-public:
-  virtual void do_nmethod(nmethod* nm) {
-    if (nm->is_alive() && nm->is_unloading()) {
-      nm->make_unloaded();
-    }
-  }
-};
-
-class ZNMethodTablePurgeTask : public ZTask {
-private:
-  ZNMethodTablePurgeClosure _cl;
-
-public:
-  ZNMethodTablePurgeTask() :
-      ZTask("ZNMethodTablePurgeTask"),
-      _cl() {
-    ZNMethodTable::nmethods_do_begin();
-  }
-
-  ~ZNMethodTablePurgeTask() {
-    ZNMethodTable::nmethods_do_end();
-  }
-
-  virtual void work() {
-    ZNMethodTable::nmethods_do(&_cl);
-  }
-};
-
-void ZNMethodTable::purge(ZWorkers* workers) {
-  ZNMethodTablePurgeTask task;
-  workers->run_concurrent(&task);
-}
--- a/src/hotspot/share/gc/z/zNMethodTable.hpp	Wed Feb 20 12:04:12 2019 +0100
+++ b/src/hotspot/share/gc/z/zNMethodTable.hpp	Thu Feb 21 14:24:44 2019 +0100
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2017, 2018, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2017, 2019, Oracle and/or its affiliates. All rights reserved.
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  *
  * This code is free software; you can redistribute it and/or modify it
@@ -24,17 +24,12 @@
 #ifndef SHARE_GC_Z_ZNMETHODTABLE_HPP
 #define SHARE_GC_Z_ZNMETHODTABLE_HPP
 
-#include "gc/z/zArray.hpp"
-#include "gc/z/zGlobals.hpp"
-#include "gc/z/zLock.hpp"
-#include "gc/z/zNMethodTableEntry.hpp"
 #include "gc/z/zNMethodTableIteration.hpp"
 #include "memory/allocation.hpp"
 
 class nmethod;
 class NMethodClosure;
-class ZNMethodData;
-class ZNMethodDataOops;
+class ZNMethodTableEntry;
 class ZWorkers;
 
 class ZNMethodTable : public AllStatic {
@@ -48,36 +43,23 @@
   static ZNMethodTableEntry* create(size_t size);
   static void destroy(ZNMethodTableEntry* table);
 
-  static void attach_gc_data(nmethod* nm);
-  static void detach_gc_data(nmethod* nm);
-
   static size_t first_index(const nmethod* nm, size_t size);
   static size_t next_index(size_t prev_index, size_t size);
 
-  static void wait_until_iteration_done();
-
   static bool register_entry(ZNMethodTableEntry* table, size_t size, nmethod* nm);
   static void unregister_entry(ZNMethodTableEntry* table, size_t size, nmethod* nm);
 
   static void rebuild(size_t new_size);
   static void rebuild_if_needed();
 
-  static void log_register(const nmethod* nm);
-  static void log_unregister(const nmethod* nm);
-
 public:
   static size_t registered_nmethods();
   static size_t unregistered_nmethods();
 
   static void register_nmethod(nmethod* nm);
   static void unregister_nmethod(nmethod* nm);
-  static void disarm_nmethod(nmethod* nm);
 
-  static ZReentrantLock* lock_for_nmethod(nmethod* nm);
-
-  static void oops_do(OopClosure* cl);
-
-  static void oops_do(nmethod* nm, OopClosure* cl);
+  static void wait_until_iteration_done();
 
   static void nmethods_do_begin();
   static void nmethods_do_end();
--- a/src/hotspot/share/gc/z/zRootsIterator.cpp	Wed Feb 20 12:04:12 2019 +0100
+++ b/src/hotspot/share/gc/z/zRootsIterator.cpp	Thu Feb 21 14:24:44 2019 +0100
@@ -33,7 +33,7 @@
 #include "gc/shared/suspendibleThreadSet.hpp"
 #include "gc/z/zBarrierSetNMethod.hpp"
 #include "gc/z/zGlobals.hpp"
-#include "gc/z/zNMethodTable.hpp"
+#include "gc/z/zNMethod.hpp"
 #include "gc/z/zOopClosures.inline.hpp"
 #include "gc/z/zRootsIterator.hpp"
 #include "gc/z/zStat.hpp"
@@ -184,7 +184,7 @@
   if (ClassUnloading) {
     nmethod::oops_do_marking_prologue();
   } else {
-    ZNMethodTable::nmethods_do_begin();
+    ZNMethod::oops_do_begin();
   }
 }
 
@@ -194,7 +194,7 @@
   if (ClassUnloading) {
     nmethod::oops_do_marking_epilogue();
   } else {
-    ZNMethodTable::nmethods_do_end();
+    ZNMethod::oops_do_end();
   }
   JvmtiExport::gc_epilogue();
 
@@ -242,7 +242,7 @@
 
 void ZRootsIterator::do_code_cache(ZRootsIteratorClosure* cl) {
   ZStatTimer timer(ZSubPhasePauseRootsCodeCache);
-  ZNMethodTable::oops_do(cl);
+  ZNMethod::oops_do(cl);
 }
 
 void ZRootsIterator::oops_do(ZRootsIteratorClosure* cl, bool visit_jvmti_weak_export) {
--- a/src/hotspot/share/gc/z/zUnload.cpp	Wed Feb 20 12:04:12 2019 +0100
+++ b/src/hotspot/share/gc/z/zUnload.cpp	Thu Feb 21 14:24:44 2019 +0100
@@ -30,7 +30,7 @@
 #include "gc/shared/gcBehaviours.hpp"
 #include "gc/shared/suspendibleThreadSet.hpp"
 #include "gc/z/zLock.inline.hpp"
-#include "gc/z/zNMethodTable.hpp"
+#include "gc/z/zNMethod.hpp"
 #include "gc/z/zOopClosures.hpp"
 #include "gc/z/zStat.hpp"
 #include "gc/z/zUnload.hpp"
@@ -75,7 +75,7 @@
 public:
   virtual bool is_unloading(CompiledMethod* method) const {
     nmethod* const nm = method->as_nmethod();
-    ZReentrantLock* const lock = ZNMethodTable::lock_for_nmethod(nm);
+    ZReentrantLock* const lock = ZNMethod::lock_for_nmethod(nm);
     if (lock == NULL) {
       return is_unloading(nm);
     } else {
@@ -89,7 +89,7 @@
 public:
   virtual bool lock(CompiledMethod* method) {
     nmethod* const nm = method->as_nmethod();
-    ZReentrantLock* const lock = ZNMethodTable::lock_for_nmethod(nm);
+    ZReentrantLock* const lock = ZNMethod::lock_for_nmethod(nm);
     if (lock != NULL) {
       lock->lock();
     }
@@ -98,7 +98,7 @@
 
   virtual void unlock(CompiledMethod* method) {
     nmethod* const nm = method->as_nmethod();
-    ZReentrantLock* const lock = ZNMethodTable::lock_for_nmethod(nm);
+    ZReentrantLock* const lock = ZNMethod::lock_for_nmethod(nm);
     if (lock != NULL) {
       lock->unlock();
     }
@@ -110,7 +110,7 @@
     }
 
     nmethod* const nm = method->as_nmethod();
-    ZReentrantLock* const lock = ZNMethodTable::lock_for_nmethod(nm);
+    ZReentrantLock* const lock = ZNMethod::lock_for_nmethod(nm);
     return lock == NULL || lock->is_owned();
   }
 };
@@ -149,7 +149,7 @@
 
   Klass::clean_weak_klass_links(unloading_occurred);
 
-  ZNMethodTable::unlink(_workers, unloading_occurred);
+  ZNMethod::unlink(_workers, unloading_occurred);
 
   DependencyContext::cleaning_end();
 }
@@ -157,7 +157,7 @@
 void ZUnload::purge() {
   {
     SuspendibleThreadSetJoiner sts;
-    ZNMethodTable::purge(_workers);
+    ZNMethod::purge(_workers);
   }
 
   ClassLoaderDataGraph::purge();