/*
 * Copyright (c) 2011, 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
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 */

#include "precompiled.hpp"
#include "gc/g1/g1CollectedHeap.inline.hpp"
#include "gc/g1/g1MonitoringSupport.hpp"
#include "gc/g1/g1Policy.hpp"
#include "gc/g1/g1MemoryPool.hpp"
#include "gc/shared/hSpaceCounters.hpp"
#include "memory/metaspaceCounters.hpp"
#include "services/memoryPool.hpp"

class G1GenerationCounters : public GenerationCounters {
protected:
  G1MonitoringSupport* _g1mm;

public:
  G1GenerationCounters(G1MonitoringSupport* g1mm,
                       const char* name, int ordinal, int spaces,
                       size_t min_capacity, size_t max_capacity,
                       size_t curr_capacity)
  : GenerationCounters(name, ordinal, spaces, min_capacity,
                       max_capacity, curr_capacity), _g1mm(g1mm) { }
};

class G1YoungGenerationCounters : public G1GenerationCounters {
public:
  // We pad the capacity three times given that the young generation
  // contains three spaces (eden and two survivors).
  G1YoungGenerationCounters(G1MonitoringSupport* g1mm, const char* name, size_t max_size)
  : G1GenerationCounters(g1mm, name, 0 /* ordinal */, 3 /* spaces */,
                         G1MonitoringSupport::pad_capacity(0, 3) /* min_capacity */,
                         G1MonitoringSupport::pad_capacity(max_size, 3),
                         G1MonitoringSupport::pad_capacity(0, 3) /* curr_capacity */) {
    if (UsePerfData) {
      update_all();
    }
  }

  virtual void update_all() {
    size_t committed =
      G1MonitoringSupport::pad_capacity(_g1mm->young_gen_committed(), 3);
    _current_size->set_value(committed);
  }
};

class G1OldGenerationCounters : public G1GenerationCounters {
public:
  G1OldGenerationCounters(G1MonitoringSupport* g1mm, const char* name, size_t max_size)
  : G1GenerationCounters(g1mm, name, 1 /* ordinal */, 1 /* spaces */,
                         G1MonitoringSupport::pad_capacity(0) /* min_capacity */,
                         G1MonitoringSupport::pad_capacity(max_size),
                         G1MonitoringSupport::pad_capacity(0) /* curr_capacity */) {
    if (UsePerfData) {
      update_all();
    }
  }

  virtual void update_all() {
    size_t committed =
      G1MonitoringSupport::pad_capacity(_g1mm->old_gen_committed());
    _current_size->set_value(committed);
  }
};

size_t G1MonitoringSupport::old_gen_committed() {
  return _old_space_committed +
    (use_legacy_monitoring() ? 0 : _humongous_space_committed + _archive_space_committed);
}

size_t G1MonitoringSupport::old_gen_used() {
  return old_space_used() +
    (use_legacy_monitoring() ? 0 : humongous_space_used() + archive_space_used());
}

G1MonitoringSupport::G1MonitoringSupport(G1CollectedHeap* g1h) :
  _g1h(g1h),
  _use_legacy_monitoring(G1UseLegacyMonitoring),

  _full_memory_manager(G1UseLegacyMonitoring ? "G1 Old Generation" : "G1 Full", "end of major GC"),
  _incremental_memory_manager("G1 Young Generation", "end of minor GC"),
  _young_memory_manager("G1 Young", "end of young GC"),
  _mixed_memory_manager("G1 Mixed", "end of mixed GC"),
  _conc_memory_manager("G1 Concurrent Cycle", "end of concurrent cycle"),

  _eden_space_pool(NULL),
  _survivor_space_pool(NULL),
  _old_space_pool(NULL),
  _archive_space_pool(NULL),
  _humongous_space_pool(NULL),

  _incremental_collection_counters(NULL),
  _full_collection_counters(NULL),
  _conc_collection_counters(NULL),

  _young_gen_counters(NULL),     _old_gen_counters(NULL),

  _old_space_counters(NULL),     _eden_space_counters(NULL),
  _from_space_counters(NULL),    _to_space_counters(NULL),

  _overall_committed(0),         _overall_used(0),
  _young_gen_committed(0),
  _eden_space_committed(0),      _eden_space_used(0),
  _survivor_space_committed(0),  _survivor_space_used(0),
  _old_space_committed(0),       _old_space_used(0),
  _archive_space_committed(0),   _archive_space_used(0),
  _humongous_space_committed(0), _humongous_space_used(0) {

  // Counters for garbage collections.

  // Compute initial capacities. Somewhat random, as they depend
  // on what's happened so far during JVM initialization.
  recalculate_sizes();

  //  name "collector.0".  In a generational collector this would be the
  // young generation collection.
  _incremental_collection_counters =
    new CollectorCounters("G1 incremental collections", 0);
  //   name "collector.1".  In a generational collector this would be the
  // old generation collection.
  _full_collection_counters =
    new CollectorCounters("G1 stop-the-world full collections", 1);
  //   name "collector.2".  In a generational collector this would be the
  // STW phases in concurrent collection.
  _conc_collection_counters =
    new CollectorCounters("G1 stop-the-world phases", 2);

  // "Generation" and "Space" counters.
  //
  //  name "generation.1" This is logically the old generation in
  // generational GC terms.  The "1, 1" parameters are for
  // the n-th generation (=1) with 1 space.
  // Counters are created from minCapacity, maxCapacity, and capacity
  _old_gen_counters = new G1OldGenerationCounters(this, "old", _g1h->max_capacity());

  //  name  "generation.1.space.0"
  // Counters are created from maxCapacity, capacity, initCapacity,
  // and used.
  _old_space_counters = new HSpaceCounters(_old_gen_counters->name_space(),
    "space", 0 /* ordinal */,
    pad_capacity(g1h->max_capacity()) /* max_capacity */,
    pad_capacity(old_gen_committed()) /* init_capacity */);

  //   Young collection set
  //  name "generation.0".  This is logically the young generation.
  //  The "0, 3" are parameters for the n-th generation (=0) with 3 spaces.
  // See  _old_collection_counters for additional counters
  _young_gen_counters = new G1YoungGenerationCounters(this, "young", _g1h->max_capacity());

  const char* young_collection_name_space = _young_gen_counters->name_space();

  //  name "generation.0.space.0"
  // See _old_space_counters for additional counters
  _eden_space_counters = new HSpaceCounters(young_collection_name_space,
    "eden", 0 /* ordinal */,
    pad_capacity(g1h->max_capacity()) /* max_capacity */,
    pad_capacity(_eden_space_committed) /* init_capacity */);

  //  name "generation.0.space.1"
  // See _old_space_counters for additional counters
  // Set the arguments to indicate that this survivor space is not used.
  _from_space_counters = new HSpaceCounters(young_collection_name_space,
    "s0", 1 /* ordinal */,
    pad_capacity(0) /* max_capacity */,
    pad_capacity(0) /* init_capacity */);
  // Given that this survivor space is not used, we update it here
  // once to reflect that its used space is 0 so that we don't have to
  // worry about updating it again later.
  if (UsePerfData) {
    _from_space_counters->update_used(0);
  }

  //  name "generation.0.space.2"
  // See _old_space_counters for additional counters
  _to_space_counters = new HSpaceCounters(young_collection_name_space,
    "s1", 2 /* ordinal */,
    pad_capacity(g1h->max_capacity()) /* max_capacity */,
    pad_capacity(_survivor_space_committed) /* init_capacity */);
}

G1MonitoringSupport::~G1MonitoringSupport() {
  delete _eden_space_pool;
  delete _survivor_space_pool;
  delete _old_space_pool;
  delete _archive_space_pool;
  delete _humongous_space_pool;
}

void G1MonitoringSupport::initialize_serviceability() {
  _eden_space_pool = new G1EdenPool(_g1h, _eden_space_committed);
  _survivor_space_pool = new G1SurvivorPool(_g1h, _survivor_space_committed);
  _old_space_pool = new G1OldPool(_g1h, _old_space_committed, _g1h->max_capacity());
  _archive_space_pool = new G1ArchivePool(_g1h, _archive_space_committed);
  _humongous_space_pool = new G1HumongousPool(_g1h, _humongous_space_committed);

  // Pools must be added to each memory manager in the order specified
  // below: TestMemoryMXBeansAndPoolsPresence.java expects them so.

  if (use_legacy_monitoring()) {
    _incremental_memory_manager.add_pool(_eden_space_pool);
    _incremental_memory_manager.add_pool(_survivor_space_pool);
    // Incremental GCs can affect the humongous pool, but legacy behavior ignores it.
    //  _incremental_memory_manager.add_pool(_humongous_space_pool);
    _incremental_memory_manager.add_pool(_old_space_pool, false /* always_affected_by_gc */);
  } else {
    _young_memory_manager.add_pool(_eden_space_pool);
    _young_memory_manager.add_pool(_survivor_space_pool);
    _young_memory_manager.add_pool(_humongous_space_pool);

    _mixed_memory_manager.add_pool(_eden_space_pool);
    _mixed_memory_manager.add_pool(_survivor_space_pool);
    _mixed_memory_manager.add_pool(_humongous_space_pool);
    _mixed_memory_manager.add_pool(_old_space_pool);

    _conc_memory_manager.add_pool(_humongous_space_pool);
    _conc_memory_manager.add_pool(_old_space_pool);
  }

  _full_memory_manager.add_pool(_eden_space_pool);
  _full_memory_manager.add_pool(_survivor_space_pool);
  if (!use_legacy_monitoring()) {
    _full_memory_manager.add_pool(_humongous_space_pool);
    _full_memory_manager.add_pool(_archive_space_pool);
  }
  _full_memory_manager.add_pool(_old_space_pool);

  // Update pool and jstat counter content
  update_sizes();
}

GrowableArray<GCMemoryManager*> G1MonitoringSupport::memory_managers() {
  GrowableArray<GCMemoryManager*> memory_managers(4);
  if (use_legacy_monitoring()) {
    memory_managers.append(&_incremental_memory_manager);
  } else {
    memory_managers.append(&_young_memory_manager);
    memory_managers.append(&_mixed_memory_manager);
    memory_managers.append(&_conc_memory_manager);
  }
  memory_managers.append(&_full_memory_manager);
  return memory_managers;
}

GrowableArray<MemoryPool*> G1MonitoringSupport::memory_pools() {
  GrowableArray<MemoryPool*> memory_pools(5);
  memory_pools.append(_eden_space_pool);
  memory_pools.append(_survivor_space_pool);
  memory_pools.append(_old_space_pool);
  if (!use_legacy_monitoring()) {
    memory_pools.append(_humongous_space_pool);
    memory_pools.append(_archive_space_pool);
  }
  return memory_pools;
}

void G1MonitoringSupport::recalculate_sizes() {
  assert_heap_locked_or_at_safepoint(true);

  MutexLockerEx x(MonitoringSupport_lock, Mutex::_no_safepoint_check_flag);

  // Recalculate all sizes from scratch.

  uint eden_regions_count = _g1h->eden_regions_count();
  uint survivor_regions_count = _g1h->survivor_regions_count();
  uint young_regions_count = _g1h->young_regions_count();
  assert(young_regions_count == eden_regions_count + survivor_regions_count, "invariant");
  uint old_regions_count = _g1h->old_regions_count();
  uint archive_regions_count = _g1h->archive_regions_count();
  uint humongous_regions_count = _g1h->humongous_regions_count();

  // Max length includes any potential extensions to the young gen
  // we'll do when the GC locker is active.
  uint young_regions_count_max = _g1h->g1_policy()->young_list_max_length();
  assert(young_regions_count_max >= survivor_regions_count, "invariant");
  uint eden_regions_count_max = young_regions_count_max - survivor_regions_count;

  _overall_used = _g1h->used_unlocked();
  _eden_space_used = (size_t)eden_regions_count * HeapRegion::GrainBytes;
  _survivor_space_used = (size_t)survivor_regions_count * HeapRegion::GrainBytes;
  _archive_space_used = (size_t)archive_regions_count * HeapRegion::GrainBytes;
  _humongous_space_used = (size_t)humongous_regions_count * HeapRegion::GrainBytes;
 
  // We separately keep track of the humongous and archive spaces, no
  // matter which mode we're in. In legacy mode, the old space is the
  // sum of the old, humongous and archive spaces, but in default mode
  // it does not include the humongous and archive spaces. The old
  // generation as a whole (in contrast to the old space), always
  // includes the humongous and archive spaces. See the definitions of
  // old_gen_committed() and old_gen_used().
  size_t excess_old = use_legacy_monitoring() ? 0 : _humongous_space_used + _archive_space_used;
  _old_space_used = subtract_up_to_zero(_overall_used, _eden_space_used + _survivor_space_used + excess_old);

  // First, calculate the committed sizes that can be calculated independently.
  _survivor_space_committed = _survivor_space_used;
  _old_space_committed = HeapRegion::align_up_to_region_byte_size(_old_space_used);
  _archive_space_committed = _archive_space_used;
  _humongous_space_committed = _humongous_space_used;
 
  // Next, start with the overall committed size.
  size_t committed = _overall_committed = _g1h->capacity();

  // Remove the committed size we have calculated so far (for the
  // survivor, old, archive, and humongous spaces).
  assert(committed >= (_survivor_space_committed + _old_space_committed + excess_old), "sanity");
  committed -= _survivor_space_committed + _old_space_committed + excess_old;
 
  // Next, calculate and remove the committed size for the eden.
  _eden_space_committed = (size_t)eden_regions_count_max * HeapRegion::GrainBytes;
  // Somewhat defensive: be robust in case there are inaccuracies in
  // the calculations
  _eden_space_committed = MIN2(_eden_space_committed, committed);
  committed -= _eden_space_committed;

  // Finally, give the rest to the old space...
  _old_space_committed += committed;
  // ..and calculate the young gen committed.
  _young_gen_committed = _eden_space_committed + _survivor_space_committed;

  assert(_overall_committed ==
         (_eden_space_committed + _survivor_space_committed + _old_space_committed + excess_old),
         "the committed sizes should add up");
  // Somewhat defensive: cap the eden used size to make sure it
  // never exceeds the committed size.
  _eden_space_used = MIN2(_eden_space_used, _eden_space_committed);

  // _survivor_space_committed and _old_space_committed are calculated in terms of
  // the corresponding _*_used value, so the next two conditions should hold.
  assert(_survivor_space_used <= _survivor_space_committed, "post-condition");
  assert(_old_space_used <= _old_space_committed, "post-condition");
}

void G1MonitoringSupport::update_sizes() {
  recalculate_sizes();
  if (UsePerfData) {
    _eden_space_counters->update_capacity(pad_capacity(_eden_space_committed));
    _eden_space_counters->update_used(eden_space_used());
    // only the "to" survivor space is active, so we don't need to
    // update the counters for the "from" survivor space
    _to_space_counters->update_capacity(pad_capacity(_survivor_space_committed));
    _to_space_counters->update_used(survivor_space_used());
    _old_space_counters->update_capacity(pad_capacity(old_gen_committed()));
    _old_space_counters->update_used(old_gen_used());

    _young_gen_counters->update_all();
    _old_gen_counters->update_all();

    MetaspaceCounters::update_performance_counters();
    CompressedClassSpaceCounters::update_performance_counters();
  }
}

void G1MonitoringSupport::update_eden_size() {
  // Recalculate everything. Should be fast enough and we are sure not to miss anything.
  recalculate_sizes();
  if (UsePerfData) {
    _eden_space_counters->update_capacity(pad_capacity(_eden_space_committed));
    _eden_space_counters->update_used(eden_space_used());
  }
}

MemoryUsage G1MonitoringSupport::memory_usage() {
  MutexLockerEx x(MonitoringSupport_lock, Mutex::_no_safepoint_check_flag);
  return MemoryUsage(InitialHeapSize, _overall_used, _overall_committed, _g1h->max_capacity());
}

MemoryUsage G1MonitoringSupport::eden_space_memory_usage(size_t initial_size, size_t max_size) {
  MutexLockerEx x(MonitoringSupport_lock, Mutex::_no_safepoint_check_flag);
  return MemoryUsage(initial_size, eden_space_used(), _eden_space_committed, max_size);
}

MemoryUsage G1MonitoringSupport::survivor_space_memory_usage(size_t initial_size, size_t max_size) {
  MutexLockerEx x(MonitoringSupport_lock, Mutex::_no_safepoint_check_flag);
  return MemoryUsage(initial_size, survivor_space_used(), _survivor_space_committed, max_size);
}

MemoryUsage G1MonitoringSupport::old_space_memory_usage(size_t initial_size, size_t max_size) {
  MutexLockerEx x(MonitoringSupport_lock, Mutex::_no_safepoint_check_flag);
  return MemoryUsage(initial_size, old_space_used(), _old_space_committed, max_size);
}

MemoryUsage G1MonitoringSupport::archive_space_memory_usage(size_t initial_size, size_t max_size) {
  MutexLockerEx x(MonitoringSupport_lock, Mutex::_no_safepoint_check_flag);
  return MemoryUsage(initial_size, archive_space_used(), _archive_space_committed, max_size);
}

MemoryUsage G1MonitoringSupport::humongous_space_memory_usage(size_t initial_size, size_t max_size) {
  MutexLockerEx x(MonitoringSupport_lock, Mutex::_no_safepoint_check_flag);
  return MemoryUsage(initial_size, humongous_space_used(), _humongous_space_committed, max_size);
}

TraceConcMemoryManagerStats::TraceConcMemoryManagerStats(Stage stage, GCCause::Cause cause)
  : TraceMemoryManagerStats() {
  GCMemoryManager* manager = G1CollectedHeap::heap()->g1mm()->conc_memory_manager();
  switch (stage) {
    case CycleStart:
      initialize(manager /* GC manager */,
                 cause   /* cause of the GC */,
                 true    /* allMemoryPoolsAffected */,
                 true    /* recordGCBeginTime */,
                 true    /* recordPreGCUsage */,
                 false   /* recordPeakUsage */,
                 false   /* recordPostGCusage */,
                 false   /* recordAccumulatedGCTime */,
                 false   /* recordGCEndTime */,
                 false   /* countCollection */ );
      break;
    case Remark:
    case Cleanup:
      initialize(manager /* GC manager */,
                 cause   /* cause of the GC */,
                 true    /* allMemoryPoolsAffected */,
                 false   /* recordGCBeginTime */,
                 false   /* recordPreGCUsage */,
                 false   /* recordPeakUsage */,
                 false   /* recordPostGCusage */,
                 true    /* recordAccumulatedGCTime */,
                 false   /* recordGCEndTime */,
                 false   /* countCollection */ );
      break;
    case CycleEnd:
      initialize(manager /* GC manager */,
                 cause   /* cause of the GC */,
                 true    /* allMemoryPoolsAffected */,
                 false   /* recordGCBeginTime */,
                 false   /* recordPreGCUsage */,
                 true    /* recordPeakUsage */,
                 true    /* recordPostGCusage */,
                 false   /* recordAccumulatedGCTime */,
                 true    /* recordGCEndTime */,
                 true    /* countCollection */ );
      break;
    default:
      ShouldNotReachHere();
      break;
  }
}

G1MonitoringScope::G1MonitoringScope(G1MonitoringSupport* g1mm, bool full_gc, bool mixed_gc) :
  _tcs(full_gc ? g1mm->_full_collection_counters : g1mm->_incremental_collection_counters),
  _tms(full_gc                        ? &g1mm->_full_memory_manager :
       (g1mm->use_legacy_monitoring() ? &g1mm->_incremental_memory_manager :
       (mixed_gc                      ? &g1mm->_mixed_memory_manager :
        /* young */                     &g1mm->_young_memory_manager)),
       g1mm->_g1h->gc_cause(),
       full_gc || (g1mm->use_legacy_monitoring() ? mixed_gc : true) /* allMemoryPoolsAffected */) {
}