8329488: Move OopStorage code from safepoint cleanup and remove safepoint cleanup code

Reviewed-by: kbarrett, eosterlund

src/hotspot/share/gc/shared/oopStorage.cpp

@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2018, 2023, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2018, 2024, 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
@@ -410,7 +410,7 @@ OopStorage::Block::block_for_ptr(const OopStorage* owner, const oop* ptr) {
 // allocations until some entries in it are released.
 //
 // release() is performed lock-free. (Note: This means it can't notify the
-// service thread of pending cleanup work.  It must be lock-free because
+// ServiceThread of pending cleanup work.  It must be lock-free because
 // it is called in all kinds of contexts where even quite low ranked locks
 // may be held.)  release() first looks up the block for
 // the entry, using address alignment to find the enclosing block (thereby
@@ -705,7 +705,7 @@ void OopStorage::Block::release_entries(uintx releasing, OopStorage* owner) {
       // Only request cleanup for to-empty transitions, not for from-full.
       // There isn't any rush to process from-full transitions.  Allocation
       // will reduce deferrals before allocating new blocks, so may process
-      // some.  And the service thread will drain the entire deferred list
+      // some.  And the ServiceThread will drain the entire deferred list
       // if there are any pending to-empty transitions.
       if (releasing == old_allocated) {
         owner->record_needs_cleanup();
@@ -880,67 +880,51 @@ bool OopStorage::should_report_num_dead() const {
 }
 
 // Managing service thread notifications.
-//
+
-// We don't want cleanup work to linger indefinitely, but we also don't want
-// to run the service thread too often.  We're also very limited in what we
-// can do in a release operation, where cleanup work is created.
-//
 // When a release operation changes a block's state to empty, it records the
 // need for cleanup in both the associated storage object and in the global
-// request state.  A safepoint cleanup task notifies the service thread when
+// request state. The ServiceThread checks at timed intervals if
 // there may be cleanup work for any storage object, based on the global
-// request state.  But that notification is deferred if the service thread
+// request state.  We don't want to run empty block cleanup too often in the
-// has run recently, and we also avoid duplicate notifications.  The service
+// face of frequent explicit ServiceThread wakeups, hence the defer period.
-// thread updates the timestamp and resets the state flags on every iteration.
 
 // Global cleanup request state.
 static volatile bool needs_cleanup_requested = false;
 
-// Flag for avoiding duplicate notifications.
+// Time after which a cleanup is permitted.
-static bool needs_cleanup_triggered = false;
+static jlong cleanup_permit_time = 0;
 
-// Time after which a notification can be made.
+// Minimum time between ServiceThread cleanups.
-static jlong cleanup_trigger_permit_time = 0;
+// The value of 500ms was an arbitrary choice; frequent, but not too frequent.
-
+const jlong cleanup_defer_period = 500 * NANOSECS_PER_MILLISEC;
-// Minimum time since last service thread check before notification is
-// permitted.  The value of 500ms was an arbitrary choice; frequent, but not
-// too frequent.
-const jlong cleanup_trigger_defer_period = 500 * NANOSECS_PER_MILLISEC;
-
-void OopStorage::trigger_cleanup_if_needed() {
-  MonitorLocker ml(Service_lock, Monitor::_no_safepoint_check_flag);
-  if (Atomic::load(&needs_cleanup_requested) &&
-      !needs_cleanup_triggered &&
-      (os::javaTimeNanos() > cleanup_trigger_permit_time)) {
-    needs_cleanup_triggered = true;
-    ml.notify_all();
-  }
-}
 
 bool OopStorage::has_cleanup_work_and_reset() {
   assert_lock_strong(Service_lock);
-  cleanup_trigger_permit_time =
+
-    os::javaTimeNanos() + cleanup_trigger_defer_period;
+  if (Atomic::load_acquire(&needs_cleanup_requested) &&
-  needs_cleanup_triggered = false;
+      os::javaTimeNanos() > cleanup_permit_time) {
-  // Set the request flag false and return its old value.
+    cleanup_permit_time =
-  // Needs to be atomic to avoid dropping a concurrent request.
+      os::javaTimeNanos() + cleanup_defer_period;
-  // Can't use Atomic::xchg, which may not support bool.
+    // Set the request flag false and return its old value.
-  return Atomic::cmpxchg(&needs_cleanup_requested, true, false);
+    Atomic::release_store(&needs_cleanup_requested, false);
+    return true;
+  } else {
+    return false;
+  }
 }
 
-// Record that cleanup is needed, without notifying the Service thread.
+// Record that cleanup is needed, without notifying the Service thread, because
-// Used by release(), where we can't lock even Service_lock.
+// we can't lock the Service_lock.  Used by release().
 void OopStorage::record_needs_cleanup() {
-  // Set local flag first, else service thread could wake up and miss
+  // Set local flag first, else ServiceThread could wake up and miss
-  // the request.  This order may instead (rarely) unnecessarily notify.
+  // the request.
   Atomic::release_store(&_needs_cleanup, true);
   Atomic::release_store_fence(&needs_cleanup_requested, true);
 }
 
 bool OopStorage::delete_empty_blocks() {
-  // Service thread might have oopstorage work, but not for this object.
+  // ServiceThread might have oopstorage work, but not for this object.
-  // Check for deferred updates even though that's not a service thread
+  // But check for deferred updates, which might provide cleanup work.
-  // trigger; since we're here, we might as well process them.
   if (!Atomic::load_acquire(&_needs_cleanup) &&
       (Atomic::load_acquire(&_deferred_updates) == nullptr)) {
     return false;
@@ -986,7 +970,7 @@ bool OopStorage::delete_empty_blocks() {
         // Don't interfere with an active concurrent iteration.
         // Instead, give up immediately.  There is more work to do,
         // but don't re-notify, to avoid useless spinning of the
-        // service thread.  Instead, iteration completion notifies.
+        // ServiceThread.  Instead, iteration completion notifies.
         if (_concurrent_iteration_count > 0) return true;
         _active_array->remove(block);
       }
@@ -998,10 +982,8 @@ bool OopStorage::delete_empty_blocks() {
       ThreadBlockInVM tbiv(JavaThread::current());
     }
   }
-  // Exceeded work limit or can't delete last block.  This will
+  // Exceeded work limit or can't delete last block so still needs cleanup
-  // cause the service thread to loop, giving other subtasks an
+  // for the next time.
-  // opportunity to run too.  There's no need for a notification,
-  // because we are part of the service thread (unless gtesting).
   record_needs_cleanup();
   return true;
 }

src/hotspot/share/jfr/metadata/metadata.xml

@@ -1,7 +1,7 @@
 <?xml version="1.0" encoding="utf-8"?>
 
 <!--
- Copyright (c) 2012, 2023, Oracle and/or its affiliates. All rights reserved.
+ Copyright (c) 2012, 2024, 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
@@ -684,17 +684,6 @@
     <Field type="int" name="iterations" label="Iterations" description="Number of state check iterations" />
   </Event>
 
-  <Event name="SafepointCleanup" category="Java Virtual Machine, Runtime, Safepoint" label="Safepoint Cleanup" description="Safepointing begin running cleanup tasks"
-    thread="true">
-    <Field type="ulong" name="safepointId" label="Safepoint Identifier" relation="SafepointId" />
-  </Event>
-
-  <Event name="SafepointCleanupTask" category="Java Virtual Machine, Runtime, Safepoint" label="Safepoint Cleanup Task" description="Safepointing begin running cleanup tasks"
-    thread="true">
-    <Field type="ulong" name="safepointId" label="Safepoint Identifier" relation="SafepointId" />
-    <Field type="string" name="name" label="Task Name" description="The task name" />
-  </Event>
-
   <Event name="SafepointEnd" category="Java Virtual Machine, Runtime, Safepoint" label="Safepoint End" description="Safepointing end" thread="true">
     <Field type="ulong" name="safepointId" label="Safepoint Identifier" relation="SafepointId" />
   </Event>

src/hotspot/share/runtime/globals.hpp

@@ -1282,6 +1282,11 @@ const int ObjectAlignmentInBytes = 8;
           "(0 means none)")                                                 \
           range(0, max_jint)                                                \
                                                                             \
+  product(intx, ServiceThreadCleanupInterval, 1000, DIAGNOSTIC,             \
+          "Wake the ServiceThread to do periodic cleanup checks every so "  \
+          "many milliseconds (0 means none)")                               \
+          range(0, max_jint)                                                \
+                                                                            \
   product(double, SafepointTimeoutDelay, 10000,                             \
           "Delay in milliseconds for option SafepointTimeout; "             \
           "supports sub-millisecond resolution with fractional values.")    \

src/hotspot/share/runtime/safepoint.cpp

@@ -80,12 +80,6 @@ static void post_safepoint_begin_event(EventSafepointBegin& event,
   }
 }
 
-static void post_safepoint_cleanup_event(EventSafepointCleanup& event, uint64_t safepoint_id) {
-  if (event.should_commit()) {
-    event.set_safepointId(safepoint_id);
-    event.commit();
-  }
-}
 
 static void post_safepoint_synchronize_event(EventSafepointStateSynchronization& event,
                                              uint64_t safepoint_id,
@@ -101,16 +95,6 @@ static void post_safepoint_synchronize_event(EventSafepointStateSynchronization&
   }
 }
 
-static void post_safepoint_cleanup_task_event(EventSafepointCleanupTask& event,
-                                              uint64_t safepoint_id,
-                                              const char* name) {
-  if (event.should_commit()) {
-    event.set_safepointId(safepoint_id);
-    event.set_name(name);
-    event.commit();
-  }
-}
-
 static void post_safepoint_end_event(EventSafepointEnd& event, uint64_t safepoint_id) {
   if (event.should_commit()) {
     event.set_safepointId(safepoint_id);
@@ -435,14 +419,7 @@ void SafepointSynchronize::begin() {
 
   SafepointTracing::synchronized(nof_threads, initial_running, _nof_threads_hit_polling_page);
 
-  // We do the safepoint cleanup first since a GC related safepoint
-  // needs cleanup to be completed before running the GC op.
-  EventSafepointCleanup cleanup_event;
-  do_cleanup_tasks();
-  post_safepoint_cleanup_event(cleanup_event, _safepoint_id);
-
   post_safepoint_begin_event(begin_event, _safepoint_id, nof_threads, _current_jni_active_count);
-  SafepointTracing::cleanup();
 }
 
 void SafepointSynchronize::disarm_safepoint() {
@@ -507,68 +484,6 @@ void SafepointSynchronize::end() {
   post_safepoint_end_event(event, safepoint_id());
 }
 
-class ParallelCleanupTask : public WorkerTask {
-private:
-  SubTasksDone _subtasks;
-
-  class Tracer {
-  private:
-    const char*               _name;
-    EventSafepointCleanupTask _event;
-    TraceTime                 _timer;
-
-  public:
-    Tracer(const char* name) :
-        _name(name),
-        _event(),
-        _timer(name, TRACETIME_LOG(Info, safepoint, cleanup)) {}
-    ~Tracer() {
-      post_safepoint_cleanup_task_event(_event, SafepointSynchronize::safepoint_id(), _name);
-    }
-  };
-
-public:
-  ParallelCleanupTask() :
-    WorkerTask("Parallel Safepoint Cleanup"),
-    _subtasks(SafepointSynchronize::SAFEPOINT_CLEANUP_NUM_TASKS) {}
-
-  uint expected_num_workers() const {
-    uint workers = 0;
-
-    return MAX2<uint>(1, workers);
-  }
-
-  void work(uint worker_id) {
-    if (_subtasks.try_claim_task(SafepointSynchronize::SAFEPOINT_CLEANUP_REQUEST_OOPSTORAGE_CLEANUP)) {
-      // Don't bother reporting event or time for this very short operation.
-      // To have any utility we'd also want to report whether needed.
-      OopStorage::trigger_cleanup_if_needed();
-    }
-
-    _subtasks.all_tasks_claimed();
-  }
-};
-
-// Various cleaning tasks that should be done periodically at safepoints.
-void SafepointSynchronize::do_cleanup_tasks() {
-
-  TraceTime timer("safepoint cleanup tasks", TRACETIME_LOG(Info, safepoint, cleanup));
-
-  CollectedHeap* heap = Universe::heap();
-  assert(heap != nullptr, "heap not initialized yet?");
-  ParallelCleanupTask cleanup;
-  WorkerThreads* cleanup_workers = heap->safepoint_workers();
-  const uint expected_num_workers = cleanup.expected_num_workers();
-  if (cleanup_workers != nullptr && expected_num_workers > 1) {
-    // Parallel cleanup using GC provided thread pool.
-    const uint num_workers = MIN2(expected_num_workers, cleanup_workers->active_workers());
-    cleanup_workers->run_task(&cleanup, num_workers);
-  } else {
-    // Serial cleanup using VMThread.
-    cleanup.work(0);
-  }
-}
-
 // Methods for determining if a JavaThread is safepoint safe.
 
 // False means unsafe with undetermined state.
@@ -946,7 +861,6 @@ void ThreadSafepointState::handle_polling_page_exception() {
 
 jlong SafepointTracing::_last_safepoint_begin_time_ns = 0;
 jlong SafepointTracing::_last_safepoint_sync_time_ns = 0;
-jlong SafepointTracing::_last_safepoint_cleanup_time_ns = 0;
 jlong SafepointTracing::_last_safepoint_end_time_ns = 0;
 jlong SafepointTracing::_last_app_time_ns = 0;
 int SafepointTracing::_nof_threads = 0;
@@ -954,7 +868,6 @@ int SafepointTracing::_nof_running = 0;
 int SafepointTracing::_page_trap = 0;
 VM_Operation::VMOp_Type SafepointTracing::_current_type;
 jlong     SafepointTracing::_max_sync_time = 0;
-jlong     SafepointTracing::_max_cleanup_time = 0;
 jlong     SafepointTracing::_max_vmop_time = 0;
 uint64_t  SafepointTracing::_op_count[VM_Operation::VMOp_Terminating] = {0};
 
@@ -970,7 +883,7 @@ static void print_header(outputStream* st) {
 
   st->print("VM Operation                 "
             "[ threads: total initial_running ]"
-            "[ time:       sync    cleanup       vmop      total ]");
+            "[ time:       sync    vmop      total ]");
 
   st->print_cr(" page_trap_count");
 }
@@ -999,11 +912,9 @@ void SafepointTracing::statistics_log() {
            _nof_threads,
            _nof_running);
   ls.print("[       "
-           INT64_FORMAT_W(10) " " INT64_FORMAT_W(10) " "
+           INT64_FORMAT_W(10) " " INT64_FORMAT_W(10) " " INT64_FORMAT_W(10) " ]",
-           INT64_FORMAT_W(10) " " INT64_FORMAT_W(10) " ]",
            (int64_t)(_last_safepoint_sync_time_ns - _last_safepoint_begin_time_ns),
-           (int64_t)(_last_safepoint_cleanup_time_ns - _last_safepoint_sync_time_ns),
+           (int64_t)(_last_safepoint_end_time_ns - _last_safepoint_sync_time_ns),
-           (int64_t)(_last_safepoint_end_time_ns - _last_safepoint_cleanup_time_ns),
            (int64_t)(_last_safepoint_end_time_ns - _last_safepoint_begin_time_ns));
 
   ls.print_cr(INT32_FORMAT_W(16), _page_trap);
@@ -1024,8 +935,6 @@ void SafepointTracing::statistics_exit_log() {
 
   log_info(safepoint, stats)("Maximum sync time  " INT64_FORMAT" ns",
                               (int64_t)(_max_sync_time));
-  log_info(safepoint, stats)("Maximum cleanup time  " INT64_FORMAT" ns",
-                              (int64_t)(_max_cleanup_time));
   log_info(safepoint, stats)("Maximum vm operation time (except for Exit VM operation)  "
                               INT64_FORMAT " ns",
                               (int64_t)(_max_vmop_time));
@@ -1038,7 +947,6 @@ void SafepointTracing::begin(VM_Operation::VMOp_Type type) {
   // update the time stamp to begin recording safepoint time
   _last_safepoint_begin_time_ns = os::javaTimeNanos();
   _last_safepoint_sync_time_ns = 0;
-  _last_safepoint_cleanup_time_ns = 0;
 
   _last_app_time_ns = _last_safepoint_begin_time_ns - _last_safepoint_end_time_ns;
   _last_safepoint_end_time_ns = 0;
@@ -1054,19 +962,12 @@ void SafepointTracing::synchronized(int nof_threads, int nof_running, int traps)
   RuntimeService::record_safepoint_synchronized(_last_safepoint_sync_time_ns - _last_safepoint_begin_time_ns);
 }
 
-void SafepointTracing::cleanup() {
-  _last_safepoint_cleanup_time_ns = os::javaTimeNanos();
-}
-
 void SafepointTracing::end() {
   _last_safepoint_end_time_ns = os::javaTimeNanos();
 
   if (_max_sync_time < (_last_safepoint_sync_time_ns - _last_safepoint_begin_time_ns)) {
     _max_sync_time = _last_safepoint_sync_time_ns - _last_safepoint_begin_time_ns;
   }
-  if (_max_cleanup_time < (_last_safepoint_cleanup_time_ns - _last_safepoint_sync_time_ns)) {
-    _max_cleanup_time = _last_safepoint_cleanup_time_ns - _last_safepoint_sync_time_ns;
-  }
   if (_max_vmop_time < (_last_safepoint_end_time_ns - _last_safepoint_sync_time_ns)) {
     _max_vmop_time = _last_safepoint_end_time_ns - _last_safepoint_sync_time_ns;
   }
@@ -1078,14 +979,12 @@ void SafepointTracing::end() {
      "Safepoint \"%s\", "
      "Time since last: " JLONG_FORMAT " ns, "
      "Reaching safepoint: " JLONG_FORMAT " ns, "
-     "Cleanup: " JLONG_FORMAT " ns, "
      "At safepoint: " JLONG_FORMAT " ns, "
      "Total: " JLONG_FORMAT " ns",
       VM_Operation::name(_current_type),
       _last_app_time_ns,
       _last_safepoint_sync_time_ns    - _last_safepoint_begin_time_ns,
-      _last_safepoint_cleanup_time_ns - _last_safepoint_sync_time_ns,
+      _last_safepoint_end_time_ns     - _last_safepoint_sync_time_ns,
-      _last_safepoint_end_time_ns     - _last_safepoint_cleanup_time_ns,
       _last_safepoint_end_time_ns     - _last_safepoint_begin_time_ns
      );
 

src/hotspot/share/runtime/safepoint.hpp

@@ -68,13 +68,6 @@ class SafepointSynchronize : AllStatic {
                                                // VM thread and any NonJavaThread may be running.
   };
 
-  // The enums are listed in the order of the tasks when done serially.
-  enum SafepointCleanupTasks {
-    SAFEPOINT_CLEANUP_REQUEST_OOPSTORAGE_CLEANUP,
-    // Leave this one last.
-    SAFEPOINT_CLEANUP_NUM_TASKS
-  };
-
  private:
   friend class SafepointMechanism;
   friend class ThreadSafepointState;
@@ -155,8 +148,6 @@ public:
   // Exception handling for page polling
   static void handle_polling_page_exception(JavaThread *thread);
 
-  static void do_cleanup_tasks();
-
   static void set_is_at_safepoint()             { _state = _synchronized; }
   static void set_is_not_at_safepoint()         { _state = _not_synchronized; }
 
@@ -239,7 +230,6 @@ private:
   // Absolute
   static jlong _last_safepoint_begin_time_ns;
   static jlong _last_safepoint_sync_time_ns;
-  static jlong _last_safepoint_cleanup_time_ns;
   static jlong _last_safepoint_end_time_ns;
 
   // Relative
@@ -251,7 +241,6 @@ private:
 
   static VM_Operation::VMOp_Type _current_type;
   static jlong     _max_sync_time;
-  static jlong     _max_cleanup_time;
   static jlong     _max_vmop_time;
   static uint64_t  _op_count[VM_Operation::VMOp_Terminating];
 
@@ -262,7 +251,6 @@ public:
 
   static void begin(VM_Operation::VMOp_Type type);
   static void synchronized(int nof_threads, int nof_running, int traps);
-  static void cleanup();
   static void end();
 
   static void statistics_exit_log();

src/hotspot/share/runtime/serviceThread.cpp

@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2012, 2023, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2012, 2024, 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
@@ -126,8 +126,9 @@ void ServiceThread::service_thread_entry(JavaThread* jt, TRAPS) {
               (cldg_cleanup_work = ClassLoaderDataGraph::should_clean_metaspaces_and_reset()) |
               (jvmti_tagmap_work = JvmtiTagMap::has_object_free_events_and_reset())
              ) == 0) {
-        // Wait until notified that there is some work to do.
+        // Wait until notified that there is some work to do or timer expires.
-        ml.wait();
+        // Some cleanup requests don't notify the ServiceThread so work needs to be done at periodic intervals.
+        ml.wait(ServiceThreadCleanupInterval);
       }
 
       if (has_jvmti_events) {

src/jdk.jfr/share/classes/jdk/jfr/internal/query/view.ini

@@ -1,5 +1,5 @@
 ;
-; Copyright (c) 2023, Oracle and/or its affiliates. All rights reserved.
+; Copyright (c) 2023, 2024, 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
@@ -525,13 +525,13 @@ form = "COLUMN 'Event Count', 'First Recorded Event', 'Last Recorded Event',
 [jvm.safepoints]
 label = "Safepoints"
 table = "COLUMN  'Start Time', 'Duration',
-                   'State Syncronization', 'Cleanup',
+                   'State Syncronization',
                    'JNI Critical Threads', 'Total Threads'
          SELECT    B.startTime,  DIFF([B|E].startTime),
-                   S.duration, C.duration,
+                   S.duration,
                    jniCriticalThreadCount, totalThreadCount
          FROM SafepointBegin AS B, SafepointEnd AS E,
-              SafepointCleanup AS C, SafepointStateSynchronization AS S
+              SafepointStateSynchronization AS S
          GROUP BY safepointId ORDER BY B.startTime"
 
 [jvm.longest-compilations]

src/jdk.jfr/share/conf/jfr/default.jfc

@@ -200,16 +200,6 @@
       <setting name="threshold">10 ms</setting>
     </event>
 
-    <event name="jdk.SafepointCleanup">
-      <setting name="enabled">false</setting>
-      <setting name="threshold">10 ms</setting>
-    </event>
-
-    <event name="jdk.SafepointCleanupTask">
-      <setting name="enabled">false</setting>
-      <setting name="threshold">10 ms</setting>
-    </event>
-
     <event name="jdk.SafepointEnd">
       <setting name="enabled">false</setting>
       <setting name="threshold">10 ms</setting>

src/jdk.jfr/share/conf/jfr/profile.jfc

@@ -200,16 +200,6 @@
       <setting name="threshold">0 ms</setting>
     </event>
 
-    <event name="jdk.SafepointCleanup">
-      <setting name="enabled">false</setting>
-      <setting name="threshold">0 ms</setting>
-    </event>
-
-    <event name="jdk.SafepointCleanupTask">
-      <setting name="enabled">false</setting>
-      <setting name="threshold">0 ms</setting>
-    </event>
-
     <event name="jdk.SafepointEnd">
       <setting name="enabled">false</setting>
       <setting name="threshold">0 ms</setting>

test/hotspot/jtreg/gc/stress/TestReclaimStringsLeaksMemory.java

@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2018, 2023, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2018, 2024, 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
@@ -55,7 +55,7 @@ public class TestReclaimStringsLeaksMemory {
     public static void main(String[] args) throws Exception {
         ArrayList<String> baseargs = new ArrayList<>(Arrays.asList("-Xms256M",
                                                                    "-Xmx256M",
-                                                                   "-Xlog:gc*,stringtable*=debug:gc.log",
+                                                                   "-Xlog:gc*,stringtable*=debug,oopstorage+blocks=debug:gc.log",
                                                                    "-XX:NativeMemoryTracking=summary",
                                                                    "-XX:+UnlockDiagnosticVMOptions",
                                                                    "-XX:+PrintNMTStatistics" ));

test/hotspot/jtreg/runtime/logging/SafepointCleanupTest.java

@@ -1,67 +0,0 @@
-/*
- * Copyright (c) 2016, 2023, 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.
- */
-
-/*
- * @test
- * @bug 8149991
- * @summary safepoint+cleanup=info should have output from the code
- * @requires vm.flagless
- * @library /test/lib
- * @modules java.base/jdk.internal.misc
- *          java.management
- * @run driver SafepointCleanupTest
- */
-
-import jdk.test.lib.process.OutputAnalyzer;
-import jdk.test.lib.process.ProcessTools;
-
-public class SafepointCleanupTest {
-    static void analyzeOutputOn(ProcessBuilder pb) throws Exception {
-        OutputAnalyzer output = new OutputAnalyzer(pb.start());
-        output.shouldContain("[safepoint,cleanup]");
-        output.shouldContain("safepoint cleanup tasks");
-        output.shouldHaveExitValue(0);
-    }
-
-    static void analyzeOutputOff(ProcessBuilder pb) throws Exception {
-        OutputAnalyzer output = new OutputAnalyzer(pb.start());
-        output.shouldNotContain("[safepoint,cleanup]");
-        output.shouldHaveExitValue(0);
-    }
-
-    public static void main(String[] args) throws Exception {
-        ProcessBuilder pb = ProcessTools.createLimitedTestJavaProcessBuilder("-Xlog:safepoint+cleanup=info",
-                                                                             InnerClass.class.getName());
-        analyzeOutputOn(pb);
-
-        pb = ProcessTools.createLimitedTestJavaProcessBuilder("-Xlog:safepoint+cleanup=off",
-                                                              InnerClass.class.getName());
-        analyzeOutputOff(pb);
-    }
-
-    public static class InnerClass {
-        public static void main(String[] args) throws Exception {
-            System.out.println("Safepoint Cleanup test");
-        }
-    }
-}

test/jdk/jdk/jfr/event/metadata/TestLookForUntestedEvents.java

@@ -56,8 +56,7 @@ public class TestLookForUntestedEvents {
         Arrays.asList(
             "DataLoss", "IntFlag", "ReservedStackActivation", "NativeLibraryUnload",
             "DoubleFlag", "UnsignedLongFlagChanged", "IntFlagChanged",
-            "UnsignedIntFlag", "UnsignedIntFlagChanged", "DoubleFlagChanged",
+            "UnsignedIntFlag", "UnsignedIntFlagChanged", "DoubleFlagChanged")
-            "SafepointCleanupTask")
     );
 
     // GC uses specific framework to test the events, instead of using event names literally.

test/jdk/jdk/jfr/event/runtime/TestSafepointEvents.java

@@ -52,7 +52,6 @@ public class TestSafepointEvents {
     static final String[] EVENT_NAMES = new String[] {
         EventNames.SafepointBegin,
         EventNames.SafepointStateSynchronization,
-        EventNames.SafepointCleanup,
         EventNames.SafepointEnd
     };
 

test/lib/jdk/test/lib/jfr/EventNames.java

@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2015, 2023, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2015, 2024, 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
@@ -65,8 +65,6 @@ public class EventNames {
     public static final String ClassUnload = PREFIX + "ClassUnload";
     public static final String SafepointBegin = PREFIX + "SafepointBegin";
     public static final String SafepointStateSynchronization = PREFIX + "SafepointStateSynchronization";
-    public static final String SafepointCleanup = PREFIX + "SafepointCleanup";
-    public static final String SafepointCleanupTask = PREFIX + "SafepointCleanupTask";
     public static final String SafepointEnd = PREFIX + "SafepointEnd";
     public static final String ExecuteVMOperation = PREFIX + "ExecuteVMOperation";
     public static final String Shutdown = PREFIX + "Shutdown";