/*
 * Copyright (c) 2003, 2017, 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 "classfile/systemDictionary.hpp"
#include "classfile/vmSymbols.hpp"
#include "gc/shared/collectedHeap.hpp"
#include "gc/shared/generation.hpp"
#include "logging/logConfiguration.hpp"
#include "memory/heap.hpp"
#include "memory/memRegion.hpp"
#include "oops/oop.inline.hpp"
#include "runtime/globals.hpp"
#include "runtime/javaCalls.hpp"
#include "services/classLoadingService.hpp"
#include "services/lowMemoryDetector.hpp"
#include "services/management.hpp"
#include "services/memoryManager.hpp"
#include "services/memoryPool.hpp"
#include "services/memoryService.hpp"
#include "utilities/growableArray.hpp"
#include "utilities/macros.hpp"

GrowableArray<MemoryPool*>* MemoryService::_pools_list =
  new (ResourceObj::C_HEAP, mtInternal) GrowableArray<MemoryPool*>(init_pools_list_size, true);
GrowableArray<MemoryManager*>* MemoryService::_managers_list =
  new (ResourceObj::C_HEAP, mtInternal) GrowableArray<MemoryManager*>(init_managers_list_size, true);

GCMemoryManager* MemoryService::_minor_gc_manager      = NULL;
GCMemoryManager* MemoryService::_major_gc_manager      = NULL;
MemoryManager*   MemoryService::_code_cache_manager    = NULL;
GrowableArray<MemoryPool*>* MemoryService::_code_heap_pools =
    new (ResourceObj::C_HEAP, mtInternal) GrowableArray<MemoryPool*>(init_code_heap_pools_size, true);
MemoryPool*      MemoryService::_metaspace_pool        = NULL;
MemoryPool*      MemoryService::_compressed_class_pool = NULL;

class GcThreadCountClosure: public ThreadClosure {
 private:
  int _count;
 public:
  GcThreadCountClosure() : _count(0) {};
  void do_thread(Thread* thread);
  int count() { return _count; }
};

void GcThreadCountClosure::do_thread(Thread* thread) {
  _count++;
}

void MemoryService::set_universe_heap(CollectedHeap* heap) {
  ResourceMark rm; // For internal allocations in GrowableArray.
  GrowableArray<GCMemoryManager*> gc_mem_mgrs = heap->memory_managers();
  // TODO: Can this be generalized? Not all GCs have 2 separate memory managers. Some have
  // only 1, some might have more.
  assert(gc_mem_mgrs.length() == 2, "currently expect 2 GC memory managers");
  _minor_gc_manager = gc_mem_mgrs.at(0);
  _major_gc_manager = gc_mem_mgrs.at(1);
  _managers_list->append(_minor_gc_manager);
  _managers_list->append(_major_gc_manager);

  GrowableArray<MemoryPool*> gc_mem_pools = heap->memory_pools();
  _pools_list->appendAll(&gc_mem_pools);

  // set the GC thread count
  GcThreadCountClosure gctcc;
  heap->gc_threads_do(&gctcc);
  int count = gctcc.count();
  if (count > 0) {
    _minor_gc_manager->set_num_gc_threads(count);
    _major_gc_manager->set_num_gc_threads(count);
  }

  // All memory pools and memory managers are initialized.
  //
  _minor_gc_manager->initialize_gc_stat_info();
  _major_gc_manager->initialize_gc_stat_info();
}

void MemoryService::add_code_heap_memory_pool(CodeHeap* heap, const char* name) {
  // Create new memory pool for this heap
  MemoryPool* code_heap_pool = new CodeHeapPool(heap, name, true /* support_usage_threshold */);

  // Append to lists
  _code_heap_pools->append(code_heap_pool);
  _pools_list->append(code_heap_pool);

  if (_code_cache_manager == NULL) {
    // Create CodeCache memory manager
    _code_cache_manager = MemoryManager::get_code_cache_memory_manager();
    _managers_list->append(_code_cache_manager);
  }

  _code_cache_manager->add_pool(code_heap_pool);
}

void MemoryService::add_metaspace_memory_pools() {
  MemoryManager* mgr = MemoryManager::get_metaspace_memory_manager();

  _metaspace_pool = new MetaspacePool();
  mgr->add_pool(_metaspace_pool);
  _pools_list->append(_metaspace_pool);

  if (UseCompressedClassPointers) {
    _compressed_class_pool = new CompressedKlassSpacePool();
    mgr->add_pool(_compressed_class_pool);
    _pools_list->append(_compressed_class_pool);
  }

  _managers_list->append(mgr);
}

MemoryManager* MemoryService::get_memory_manager(instanceHandle mh) {
  for (int i = 0; i < _managers_list->length(); i++) {
    MemoryManager* mgr = _managers_list->at(i);
    if (mgr->is_manager(mh)) {
      return mgr;
    }
  }
  return NULL;
}

MemoryPool* MemoryService::get_memory_pool(instanceHandle ph) {
  for (int i = 0; i < _pools_list->length(); i++) {
    MemoryPool* pool = _pools_list->at(i);
    if (pool->is_pool(ph)) {
      return pool;
    }
  }
  return NULL;
}

void MemoryService::track_memory_usage() {
  // Track the peak memory usage
  for (int i = 0; i < _pools_list->length(); i++) {
    MemoryPool* pool = _pools_list->at(i);
    pool->record_peak_memory_usage();
  }

  // Detect low memory
  LowMemoryDetector::detect_low_memory();
}

void MemoryService::track_memory_pool_usage(MemoryPool* pool) {
  // Track the peak memory usage
  pool->record_peak_memory_usage();

  // Detect low memory
  if (LowMemoryDetector::is_enabled(pool)) {
    LowMemoryDetector::detect_low_memory(pool);
  }
}

void MemoryService::gc_begin(bool fullGC, bool recordGCBeginTime,
                             bool recordAccumulatedGCTime,
                             bool recordPreGCUsage, bool recordPeakUsage) {

  GCMemoryManager* mgr;
  if (fullGC) {
    mgr = _major_gc_manager;
  } else {
    mgr = _minor_gc_manager;
  }
  assert(mgr->is_gc_memory_manager(), "Sanity check");
  mgr->gc_begin(recordGCBeginTime, recordPreGCUsage, recordAccumulatedGCTime);

  // Track the peak memory usage when GC begins
  if (recordPeakUsage) {
    for (int i = 0; i < _pools_list->length(); i++) {
      MemoryPool* pool = _pools_list->at(i);
      pool->record_peak_memory_usage();
    }
  }
}

void MemoryService::gc_end(bool fullGC, bool recordPostGCUsage,
                           bool recordAccumulatedGCTime,
                           bool recordGCEndTime, bool countCollection,
                           GCCause::Cause cause) {

  GCMemoryManager* mgr;
  if (fullGC) {
    mgr = (GCMemoryManager*) _major_gc_manager;
  } else {
    mgr = (GCMemoryManager*) _minor_gc_manager;
  }
  assert(mgr->is_gc_memory_manager(), "Sanity check");

  // register the GC end statistics and memory usage
  mgr->gc_end(recordPostGCUsage, recordAccumulatedGCTime, recordGCEndTime,
              countCollection, cause);
}

void MemoryService::oops_do(OopClosure* f) {
  int i;

  for (i = 0; i < _pools_list->length(); i++) {
    MemoryPool* pool = _pools_list->at(i);
    pool->oops_do(f);
  }
  for (i = 0; i < _managers_list->length(); i++) {
    MemoryManager* mgr = _managers_list->at(i);
    mgr->oops_do(f);
  }
}

bool MemoryService::set_verbose(bool verbose) {
  MutexLocker m(Management_lock);
  // verbose will be set to the previous value
  if (verbose) {
    LogConfiguration::configure_stdout(LogLevel::Info, true, LOG_TAGS(gc));
  } else {
    LogConfiguration::configure_stdout(LogLevel::Off, true, LOG_TAGS(gc));
  }
  ClassLoadingService::reset_trace_class_unloading();

  return verbose;
}

Handle MemoryService::create_MemoryUsage_obj(MemoryUsage usage, TRAPS) {
  InstanceKlass* ik = Management::java_lang_management_MemoryUsage_klass(CHECK_NH);

  instanceHandle obj = ik->allocate_instance_handle(CHECK_NH);

  JavaValue result(T_VOID);
  JavaCallArguments args(10);
  args.push_oop(obj);                         // receiver
  args.push_long(usage.init_size_as_jlong()); // Argument 1
  args.push_long(usage.used_as_jlong());      // Argument 2
  args.push_long(usage.committed_as_jlong()); // Argument 3
  args.push_long(usage.max_size_as_jlong());  // Argument 4

  JavaCalls::call_special(&result,
                          ik,
                          vmSymbols::object_initializer_name(),
                          vmSymbols::long_long_long_long_void_signature(),
                          &args,
                          CHECK_NH);
  return obj;
}

// GC manager type depends on the type of Generation. Depending on the space
// availability and vm options the gc uses major gc manager or minor gc
// manager or both. The type of gc manager depends on the generation kind.
// For DefNew and ParNew generation doing scavenge gc uses minor gc manager (so
// _fullGC is set to false ) and for other generation kinds doing
// mark-sweep-compact uses major gc manager (so _fullGC is set to true).
TraceMemoryManagerStats::TraceMemoryManagerStats(Generation::Name kind, GCCause::Cause cause) {
  switch (kind) {
    case Generation::DefNew:
#if INCLUDE_ALL_GCS
    case Generation::ParNew:
#endif // INCLUDE_ALL_GCS
      _fullGC = false;
      break;
    case Generation::MarkSweepCompact:
#if INCLUDE_ALL_GCS
    case Generation::ConcurrentMarkSweep:
#endif // INCLUDE_ALL_GCS
      _fullGC = true;
      break;
    default:
      _fullGC = false;
      assert(false, "Unrecognized gc generation kind.");
  }
  // this has to be called in a stop the world pause and represent
  // an entire gc pause, start to finish:
  initialize(_fullGC, cause, true, true, true, true, true, true, true);
}

TraceMemoryManagerStats::TraceMemoryManagerStats(bool fullGC,
                                                 GCCause::Cause cause,
                                                 bool recordGCBeginTime,
                                                 bool recordPreGCUsage,
                                                 bool recordPeakUsage,
                                                 bool recordPostGCUsage,
                                                 bool recordAccumulatedGCTime,
                                                 bool recordGCEndTime,
                                                 bool countCollection) {
  initialize(fullGC, cause, recordGCBeginTime, recordPreGCUsage, recordPeakUsage,
             recordPostGCUsage, recordAccumulatedGCTime, recordGCEndTime,
             countCollection);
}

// for a subclass to create then initialize an instance before invoking
// the MemoryService
void TraceMemoryManagerStats::initialize(bool fullGC,
                                         GCCause::Cause cause,
                                         bool recordGCBeginTime,
                                         bool recordPreGCUsage,
                                         bool recordPeakUsage,
                                         bool recordPostGCUsage,
                                         bool recordAccumulatedGCTime,
                                         bool recordGCEndTime,
                                         bool countCollection) {
  _fullGC = fullGC;
  _recordGCBeginTime = recordGCBeginTime;
  _recordPreGCUsage = recordPreGCUsage;
  _recordPeakUsage = recordPeakUsage;
  _recordPostGCUsage = recordPostGCUsage;
  _recordAccumulatedGCTime = recordAccumulatedGCTime;
  _recordGCEndTime = recordGCEndTime;
  _countCollection = countCollection;
  _cause = cause;

  MemoryService::gc_begin(_fullGC, _recordGCBeginTime, _recordAccumulatedGCTime,
                          _recordPreGCUsage, _recordPeakUsage);
}

TraceMemoryManagerStats::~TraceMemoryManagerStats() {
  MemoryService::gc_end(_fullGC, _recordPostGCUsage, _recordAccumulatedGCTime,
                        _recordGCEndTime, _countCollection, _cause);
}