8365199: Use a set instead of a list as the intermediary Klass* storage to reduce typeset processing

src/hotspot/share/jfr/leakprofiler/checkpoint/objectSampleCheckpoint.cpp

@@ -48,14 +48,6 @@
 #include "runtime/mutexLocker.hpp"
 #include "runtime/safepoint.hpp"
 
-const unsigned int initial_size = 431;
-
-static JfrCHeapTraceIdSet* c_heap_allocate_set(int size = initial_size) {
-  return new JfrCHeapTraceIdSet(size);
-}
-
-static JfrCHeapTraceIdSet* unloaded_thread_id_set = nullptr;
-
 class ThreadIdExclusiveAccess : public StackObj {
  private:
   static Semaphore _mutex_semaphore;
@@ -66,19 +58,13 @@ class ThreadIdExclusiveAccess : public StackObj {
 
 Semaphore ThreadIdExclusiveAccess::_mutex_semaphore(1);
 
-static bool has_thread_exited(traceid tid) {
-  assert(tid != 0, "invariant");
-  if (unloaded_thread_id_set == nullptr) {
-    return false;
-  }
-  ThreadIdExclusiveAccess lock;
-  return unloaded_thread_id_set->contains(tid);
-}
+static const unsigned initial_set_size = 512;
+static JfrCHeapTraceIdSet* unloaded_thread_id_set = nullptr;
 
 static void add_to_unloaded_thread_set(traceid tid) {
   ThreadIdExclusiveAccess lock;
   if (unloaded_thread_id_set == nullptr) {
-    unloaded_thread_id_set = c_heap_allocate_set();
+    unloaded_thread_id_set = new (mtTracing) JfrCHeapTraceIdSet(initial_set_size);
   }
   unloaded_thread_id_set->add(tid);
 }
@@ -193,12 +179,6 @@ inline void BlobCache::on_unlink(BlobEntry* entry) const {
   assert(entry != nullptr, "invariant");
 }
 
-static JfrResourceAreaTraceIdSet* id_set = nullptr;
-
-static void prepare_for_resolution() {
-  id_set = new JfrResourceAreaTraceIdSet(initial_size);
-}
-
 static bool stack_trace_precondition(const ObjectSample* sample) {
   assert(sample != nullptr, "invariant");
   return sample->has_stack_trace_id() && !sample->is_dead();
@@ -213,15 +193,18 @@ static void add_to_leakp_set(const ObjectSample* sample) {
   JfrTraceId::load_leakp(object->klass());
 }
 
+static JfrResourceAreaTraceIdSet* resolution_set = nullptr;
+
 class StackTraceBlobInstaller {
  private:
   BlobCache _cache;
   void install(ObjectSample* sample);
   const JfrStackTrace* resolve(const ObjectSample* sample) const;
  public:
   StackTraceBlobInstaller() : _cache(JfrOptionSet::old_object_queue_size()) {
-    prepare_for_resolution();
+    resolution_set = new JfrResourceAreaTraceIdSet(initial_set_size);
   }
+
   void sample_do(ObjectSample* sample) {
     if (stack_trace_precondition(sample)) {
       add_to_leakp_set(sample);
@@ -314,8 +297,8 @@ static bool is_klass_unloaded(traceid klass_id) {
 
 static bool is_processed(traceid method_id) {
   assert(method_id != 0, "invariant");
-  assert(id_set != nullptr, "invariant");
-  return !id_set->add(method_id);
+  assert(resolution_set != nullptr, "invariant");
+  return !resolution_set->add(method_id);
 }
 
 void ObjectSampleCheckpoint::add_to_leakp_set(const InstanceKlass* ik, traceid method_id) {
@@ -356,7 +339,7 @@ static void write_type_set_blob(const ObjectSample* sample, JfrCheckpointWriter&
 
 static void write_thread_blob(const ObjectSample* sample, JfrCheckpointWriter& writer) {
   assert(sample->has_thread(), "invariant");
-  if (sample->is_virtual_thread() || has_thread_exited(sample->thread_id())) {
+  if (sample->is_virtual_thread() || sample->thread_exited()) {
     write_blob(sample->thread(), writer);
   }
 }
@@ -372,13 +355,13 @@ static inline bool should_write(const JfrStackTrace* stacktrace) {
 class LeakProfilerStackTraceWriter {
  private:
   JfrCheckpointWriter& _writer;
-  int _count;
+  unsigned _count;
  public:
   LeakProfilerStackTraceWriter(JfrCheckpointWriter& writer) : _writer(writer), _count(0) {
     assert(_stacktrace_id_set != nullptr, "invariant");
   }
 
-  int count() const { return _count; }
+  unsigned count() const { return _count; }
 
   void operator()(const JfrStackTrace* stacktrace) {
     if (should_write(stacktrace)) {
@@ -394,12 +377,10 @@ void ObjectSampleCheckpoint::write_stacktraces(Thread* thread) {
 
   JfrCheckpointWriter writer(thread);
   writer.write_type(TYPE_STACKTRACE);
-  const int64_t count_offset = writer.reserve(sizeof(u4)); // Don't know how many yet
-
+  writer.write_count(_stacktrace_id_set->size());
   LeakProfilerStackTraceWriter lpstw(writer);
   JfrStackTraceRepository::iterate_leakprofiler(lpstw);
   assert(lpstw.count() == _stacktrace_id_set->size(), "invariant");
-  writer.write_count(lpstw.count(), count_offset);
 }
 
 static void write_stacktrace_blob(const ObjectSample* sample, JfrCheckpointWriter& writer) {
@@ -422,6 +403,16 @@ static void write_blobs(const ObjectSample* sample, JfrCheckpointWriter& writer)
   write_type_set_blob(sample, writer);
 }
 
+static void check_if_thread_exited(const ObjectSample* sample) {
+  assert(sample != nullptr, "invariant");
+  if (sample->thread_exited() || unloaded_thread_id_set == nullptr) {
+    return;
+  }
+  if (unloaded_thread_id_set->contains(sample->thread_id())) {
+    sample->set_thread_exited();
+  }
+}
+
 class BlobWriter {
  private:
   const ObjectSampler* _sampler;
@@ -431,23 +422,36 @@ class BlobWriter {
   BlobWriter(const ObjectSampler* sampler, JfrCheckpointWriter& writer, jlong last_sweep) :
     _sampler(sampler), _writer(writer), _last_sweep(last_sweep) {}
   void sample_do(ObjectSample* sample) {
+    check_if_thread_exited(sample);
     if (sample->is_alive_and_older_than(_last_sweep)) {
       write_blobs(sample, _writer);
     }
   }
 };
 
+static void delete_unloaded_thread_id_set() {
+  if (unloaded_thread_id_set != nullptr) {
+    delete unloaded_thread_id_set;
+    unloaded_thread_id_set = nullptr;
+  }
+}
+
 static void write_sample_blobs(const ObjectSampler* sampler, bool emit_all, Thread* thread) {
   // sample set is predicated on time of last sweep
   const jlong last_sweep = emit_all ? max_jlong : ObjectSampler::last_sweep();
   JfrCheckpointWriter writer(thread, false);
   BlobWriter cbw(sampler, writer, last_sweep);
+  ThreadIdExclusiveAccess lock;
   iterate_samples(cbw, true);
+  delete_unloaded_thread_id_set();
 }
 
-static inline unsigned int set_size() {
-  const unsigned int queue_size = static_cast<unsigned int>(JfrOptionSet::old_object_queue_size());
-  return queue_size > initial_size ? queue_size : initial_size;
+static inline unsigned stacktrace_id_set_size() {
+  unsigned queue_size = static_cast<unsigned>(JfrOptionSet::old_object_queue_size());
+  if (!is_power_of_2(queue_size)) {
+    queue_size = next_power_of_2(queue_size);
+  }
+  return queue_size > initial_set_size ? queue_size : initial_set_size;
 }
 
 void ObjectSampleCheckpoint::write(const ObjectSampler* sampler, EdgeStore* edge_store, bool emit_all, Thread* thread) {
@@ -456,7 +460,9 @@ void ObjectSampleCheckpoint::write(const ObjectSampler* sampler, EdgeStore* edge
   assert(thread != nullptr, "invariant");
   {
     ResourceMark rm(thread);
-    _stacktrace_id_set = new JfrResourceAreaTraceIdSet(set_size());
+    const unsigned stacktrace_set_size = stacktrace_id_set_size();
+    assert(is_power_of_2(stacktrace_set_size), "invariant");
+    _stacktrace_id_set = new JfrResourceAreaTraceIdSet(stacktrace_set_size);
     write_sample_blobs(sampler, emit_all, thread);
     if (_stacktrace_id_set->is_nonempty()) {
       write_stacktraces(thread);

src/hotspot/share/jfr/leakprofiler/sampling/objectSample.hpp

@@ -59,6 +59,7 @@ class ObjectSample : public JfrCHeapObj {
   size_t _heap_used_at_last_gc;
   int _index;
   bool _virtual_thread;
+  mutable bool _thread_exited;
 
   void release_references() {
     _stacktrace.~JfrBlobHandle();
@@ -82,7 +83,8 @@ class ObjectSample : public JfrCHeapObj {
                    _allocated(0),
                    _heap_used_at_last_gc(0),
                    _index(0),
-                   _virtual_thread(false) {}
+                   _virtual_thread(false),
+                   _thread_exited(false) {}
 
   ObjectSample* next() const {
     return _next;
@@ -225,6 +227,15 @@ class ObjectSample : public JfrCHeapObj {
     _virtual_thread = true;
   }
 
+  bool thread_exited() const {
+    return _thread_exited;
+  }
+
+  void set_thread_exited() const {
+    assert(!_thread_exited, "invariant");
+    _thread_exited = true;
+  }
+
   const JfrBlobHandle& type_set() const {
     return _type_set;
   }

src/hotspot/share/jfr/recorder/checkpoint/jfrMetadataEvent.cpp

@@ -64,11 +64,11 @@ static void write_metadata_blob(JfrChunkWriter& chunkwriter, JavaThread* thread)
   chunkwriter.write_unbuffered(data_address, length);
 }
 
-void JfrMetadataEvent::write(JfrChunkWriter& chunkwriter) {
+size_t JfrMetadataEvent::write(JfrChunkWriter& chunkwriter) {
   assert(chunkwriter.is_valid(), "invariant");
   check_internal_types();
   if (last_metadata_id == metadata_id && chunkwriter.has_metadata()) {
-    return;
+    return 0;
   }
   JavaThread* const jt = JavaThread::current();
   DEBUG_ONLY(JfrJavaSupport::check_java_thread_in_native(jt));
@@ -87,6 +87,7 @@ void JfrMetadataEvent::write(JfrChunkWriter& chunkwriter) {
   chunkwriter.write_padded_at_offset((u4)size_written, metadata_offset);
   chunkwriter.set_last_metadata_offset(metadata_offset);
   last_metadata_id = metadata_id;
+  return 1;
 }
 
 void JfrMetadataEvent::update(jbyteArray metadata) {

src/hotspot/share/jfr/recorder/checkpoint/jfrMetadataEvent.hpp

@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2016, 2022, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2016, 2025, 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
@@ -36,7 +36,7 @@ class JfrChunkWriter;
 //
 class JfrMetadataEvent : AllStatic {
  public:
-  static void write(JfrChunkWriter& writer);
+  static size_t write(JfrChunkWriter& writer);
   static void update(jbyteArray metadata);
 };
 

src/hotspot/share/jfr/recorder/checkpoint/types/jfrTypeSet.cpp

@@ -1048,19 +1048,15 @@ class MethodIteratorHost {
  private:
   MethodCallback _method_cb;
   KlassCallback _klass_cb;
-  KlassUsedPredicate _klass_used_predicate;
-  MethodUsedPredicate _method_used_predicate;
   MethodFlagPredicate<leakp> _method_flag_predicate;
  public:
   MethodIteratorHost(JfrCheckpointWriter* writer) :
     _method_cb(writer, unloading(), false),
     _klass_cb(writer, unloading(), false),
-    _klass_used_predicate(current_epoch()),
-    _method_used_predicate(current_epoch()),
     _method_flag_predicate(current_epoch()) {}
 
   bool operator()(KlassPtr klass) {
-    if (_method_used_predicate(klass)) {
+    if (klass->is_instance_klass()) {
       const InstanceKlass* ik = InstanceKlass::cast(klass);
       while (ik != nullptr) {
         const int len = ik->methods()->length();
@@ -1075,7 +1071,7 @@ class MethodIteratorHost {
         ik = ik->previous_versions();
       }
     }
-    return _klass_used_predicate(klass) ? _klass_cb(klass) : true;
+    return _klass_cb(klass);
   }
 
   int count() const { return _method_cb.count(); }
@@ -1280,10 +1276,11 @@ static void setup(JfrCheckpointWriter* writer, JfrCheckpointWriter* leakp_writer
   _class_unload = class_unload;
   _flushpoint = flushpoint;
   if (_artifacts == nullptr) {
-    _artifacts = new JfrArtifactSet(class_unload);
+    _artifacts = new JfrArtifactSet(class_unload, previous_epoch());
   } else {
-    _artifacts->initialize(class_unload);
+    _artifacts->initialize(class_unload, previous_epoch());
   }
+  assert(current_epoch() || _leakp_writer != nullptr, "invariant");
   assert(_artifacts != nullptr, "invariant");
   assert(!_artifacts->has_klass_entries(), "invariant");
 }

src/hotspot/share/jfr/recorder/checkpoint/types/jfrTypeSetUtils.cpp

@@ -29,18 +29,23 @@
 #include "oops/oop.inline.hpp"
 #include "oops/symbol.hpp"
 
-JfrArtifactSet::JfrArtifactSet(bool class_unload) : _symbol_table(nullptr),
-                                                    _klass_list(nullptr),
-                                                    _total_count(0),
-                                                    _class_unload(class_unload) {
-  initialize(class_unload);
-  assert(_klass_list != nullptr, "invariant");
+JfrArtifactSet::JfrArtifactSet(bool class_unload, bool previous_epoch) : _symbol_table(nullptr),
+                                                                         _klass_set(nullptr),
+                                                                         _klass_loader_set(nullptr),
+                                                                         _klass_loader_leakp_set(nullptr),
+                                                                         _total_count(0),
+                                                                         _class_unload(class_unload) {
+  initialize(class_unload, previous_epoch);
+  assert(!previous_epoch || _klass_loader_leakp_set != nullptr, "invariant");
+  assert(_klass_loader_set != nullptr, "invariant");
+  assert(_klass_set != nullptr, "invariant");
 }
 
-static const size_t initial_klass_list_size = 4096;
-const int initial_klass_loader_set_size = 64;
+static unsigned initial_klass_set_size = 4096;
+static unsigned initial_klass_loader_set_size = 64;
+static unsigned initial_klass_loader_leakp_set_size = 64;
 
-void JfrArtifactSet::initialize(bool class_unload) {
+void JfrArtifactSet::initialize(bool class_unload, bool previous_epoch) {
   _class_unload = class_unload;
   if (_symbol_table == nullptr) {
     _symbol_table = JfrSymbolTable::create();
@@ -50,9 +55,11 @@ void JfrArtifactSet::initialize(bool class_unload) {
   _symbol_table->set_class_unload(class_unload);
   _total_count = 0;
   // Resource allocations. Keep in this allocation order.
-  _klass_loader_leakp_set = new GrowableArray<const Klass*>(initial_klass_loader_set_size);
-  _klass_loader_set = new GrowableArray<const Klass*>(initial_klass_loader_set_size);
-  _klass_list = new GrowableArray<const Klass*>(initial_klass_list_size);
+  if (previous_epoch) {
+    _klass_loader_leakp_set = new JfrKlassSet(initial_klass_loader_leakp_set_size);
+  }
+  _klass_loader_set = new JfrKlassSet(initial_klass_loader_set_size);
+  _klass_set = new JfrKlassSet(initial_klass_set_size);
 }
 
 void JfrArtifactSet::clear() {
@@ -93,17 +100,12 @@ traceid JfrArtifactSet::mark(uintptr_t hash, const char* const str, bool leakp)
 }
 
 bool JfrArtifactSet::has_klass_entries() const {
-  return _klass_list->is_nonempty();
-}
-
-int JfrArtifactSet::entries() const {
-  return _klass_list->length();
+  return _klass_set->is_nonempty();
 }
-
-static inline bool not_in_set(GrowableArray<const Klass*>* set, const Klass* k) {
+static inline bool not_in_set(JfrArtifactSet::JfrKlassSet* set, const Klass* k) {
   assert(set != nullptr, "invariant");
   assert(k != nullptr, "invariant");
-  return !JfrMutablePredicate<const Klass*, compare_klasses>::test(set, k);
+  return set->add(k);
 }
 
 bool JfrArtifactSet::should_do_cld_klass(const Klass* k, bool leakp) {
@@ -116,16 +118,21 @@ bool JfrArtifactSet::should_do_cld_klass(const Klass* k, bool leakp) {
 void JfrArtifactSet::register_klass(const Klass* k) {
   assert(k != nullptr, "invariant");
   assert(IS_SERIALIZED(k), "invariant");
-  assert(_klass_list != nullptr, "invariant");
-  _klass_list->append(k);
+  assert(_klass_set != nullptr, "invariant");
+  _klass_set->add(k);
 }
 
 size_t JfrArtifactSet::total_count() const {
+  assert(_klass_set != nullptr, "invariant");
+  initial_klass_set_size = MAX2(initial_klass_set_size, _klass_set->table_size());
+  assert(_klass_loader_set != nullptr, "invariant");
+  initial_klass_loader_set_size = MAX2(initial_klass_loader_set_size, _klass_loader_set->table_size());
   return _total_count;
 }
 
 void JfrArtifactSet::increment_checkpoint_id() {
   assert(_symbol_table != nullptr, "invariant");
   _symbol_table->increment_checkpoint_id();
+  assert(_klass_loader_leakp_set != nullptr, "invariant");
+  initial_klass_loader_leakp_set_size = MAX2(initial_klass_loader_leakp_set_size, _klass_loader_leakp_set->table_size());
 }
-