/*

 * Copyright (c) 2017, 2019, Red Hat, Inc. All rights reserved.

 *

 * 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 "jfr/jfrEvents.hpp"

#include "gc/shared/gcCause.hpp"

#include "gc/shared/gcTimer.hpp"

#include "gc/shared/gcTrace.hpp"

#include "gc/shared/gcWhen.hpp"

#include "gc/shenandoah/shenandoahAllocTracker.hpp"

#include "gc/shenandoah/shenandoahCollectorPolicy.hpp"

#include "gc/shenandoah/shenandoahMarkCompact.hpp"

#include "gc/shenandoah/shenandoahHeap.hpp"

#include "gc/shenandoah/shenandoahHeuristics.hpp"

#include "gc/shenandoah/shenandoahUtils.hpp"

#include "utilities/debug.hpp"

ShenandoahPhaseTimings::Phase ShenandoahGCPhase::_current_phase = ShenandoahGCPhase::_invalid_phase;

ShenandoahGCSession::ShenandoahGCSession(GCCause::Cause cause) :

  _heap(ShenandoahHeap::heap()),

  _timer(_heap->gc_timer()),

  _tracer(_heap->tracer()) {

  assert(!ShenandoahGCPhase::is_valid_phase(ShenandoahGCPhase::current_phase()),

    "No current GC phase");

  _heap->set_gc_cause(cause);

  _timer->register_gc_start();

  _tracer->report_gc_start(cause, _timer->gc_start());

  _heap->trace_heap(GCWhen::BeforeGC, _tracer);

  _heap->shenandoah_policy()->record_cycle_start();

  _heap->heuristics()->record_cycle_start();

  _trace_cycle.initialize(_heap->cycle_memory_manager(), cause,

          /* allMemoryPoolsAffected */    true,

          /* recordGCBeginTime = */       true,

          /* recordPreGCUsage = */        true,

          /* recordPeakUsage = */         true,

          /* recordPostGCUsage = */       true,

          /* recordAccumulatedGCTime = */ true,

          /* recordGCEndTime = */         true,

          /* countCollection = */         true

  );

}

ShenandoahGCSession::~ShenandoahGCSession() {

  _heap->heuristics()->record_cycle_end();

  _timer->register_gc_end();

  _heap->trace_heap(GCWhen::AfterGC, _tracer);

  _tracer->report_gc_end(_timer->gc_end(), _timer->time_partitions());

  assert(!ShenandoahGCPhase::is_valid_phase(ShenandoahGCPhase::current_phase()),

    "No current GC phase");

  _heap->set_gc_cause(GCCause::_no_gc);

}

ShenandoahGCPauseMark::ShenandoahGCPauseMark(uint gc_id, SvcGCMarker::reason_type type) :

  _heap(ShenandoahHeap::heap()), _gc_id_mark(gc_id), _svc_gc_mark(type), _is_gc_active_mark() {

  // FIXME: It seems that JMC throws away level 0 events, which are the Shenandoah

  // pause events. Create this pseudo level 0 event to push real events to level 1.

  _heap->gc_timer()->register_gc_phase_start("Shenandoah", Ticks::now());

  _trace_pause.initialize(_heap->stw_memory_manager(), _heap->gc_cause(),

          /* allMemoryPoolsAffected */    true,

          /* recordGCBeginTime = */       true,

          /* recordPreGCUsage = */        false,

          /* recordPeakUsage = */         false,

          /* recordPostGCUsage = */       false,

          /* recordAccumulatedGCTime = */ true,

          /* recordGCEndTime = */         true,

          /* countCollection = */         true

  );

  _heap->heuristics()->record_gc_start();

}

ShenandoahGCPauseMark::~ShenandoahGCPauseMark() {

  _heap->gc_timer()->register_gc_phase_end(Ticks::now());

  _heap->heuristics()->record_gc_end();

}

ShenandoahGCPhase::ShenandoahGCPhase(const ShenandoahPhaseTimings::Phase phase) :

  _heap(ShenandoahHeap::heap()), _phase(phase) {

   assert(!Thread::current()->is_Worker_thread() &&

              (Thread::current()->is_VM_thread() ||

               Thread::current()->is_ConcurrentGC_thread()),

          "Must be set by these threads");

  _parent_phase = _current_phase;

  _current_phase = phase;

  _heap->phase_timings()->record_phase_start(_phase);

}

ShenandoahGCPhase::~ShenandoahGCPhase() {

  _heap->phase_timings()->record_phase_end(_phase);

  _current_phase = _parent_phase;

}

bool ShenandoahGCPhase::is_valid_phase(ShenandoahPhaseTimings::Phase phase) {

  return phase >= 0 && phase < ShenandoahPhaseTimings::_num_phases;

}

bool ShenandoahGCPhase::is_root_work_phase() {

  switch(current_phase()) {

    case ShenandoahPhaseTimings::scan_roots:

    case ShenandoahPhaseTimings::update_roots:

    case ShenandoahPhaseTimings::init_evac:

    case ShenandoahPhaseTimings::final_update_refs_roots:

    case ShenandoahPhaseTimings::degen_gc_update_roots:

    case ShenandoahPhaseTimings::init_traversal_gc_work:

    case ShenandoahPhaseTimings::final_traversal_gc_work:

    case ShenandoahPhaseTimings::final_traversal_update_roots:

    case ShenandoahPhaseTimings::full_gc_roots:

      return true;

    default:

      return false;

  }

}

ShenandoahAllocTrace::ShenandoahAllocTrace(size_t words_size, ShenandoahAllocRequest::Type alloc_type) {

  if (ShenandoahAllocationTrace) {

    _start = os::elapsedTime();

    _size = words_size;

    _alloc_type = alloc_type;

  } else {

    _start = 0;

    _size = 0;

    _alloc_type = ShenandoahAllocRequest::Type(0);

  }

}

ShenandoahAllocTrace::~ShenandoahAllocTrace() {

  if (ShenandoahAllocationTrace) {

    double stop = os::elapsedTime();

    double duration_sec = stop - _start;

    double duration_us = duration_sec * 1000000;

    ShenandoahAllocTracker* tracker = ShenandoahHeap::heap()->alloc_tracker();

    assert(tracker != NULL, "Must be");

    tracker->record_alloc_latency(_size, _alloc_type, duration_us);

    if (duration_us > ShenandoahAllocationStallThreshold) {

      log_warning(gc)("Allocation stall: %.0f us (threshold: " INTX_FORMAT " us)",

                      duration_us, ShenandoahAllocationStallThreshold);

    }

  }

}

ShenandoahWorkerSession::ShenandoahWorkerSession(uint worker_id) : _worker_id(worker_id) {

  Thread* thr = Thread::current();

  assert(ShenandoahThreadLocalData::worker_id(thr) == ShenandoahThreadLocalData::INVALID_WORKER_ID, "Already set");

  ShenandoahThreadLocalData::set_worker_id(thr, worker_id);

}

ShenandoahConcurrentWorkerSession::~ShenandoahConcurrentWorkerSession() {

  _event.commit(GCId::current(), ShenandoahPhaseTimings::phase_name(ShenandoahGCPhase::current_phase()));

}

ShenandoahParallelWorkerSession::~ShenandoahParallelWorkerSession() {

  _event.commit(GCId::current(), _worker_id, ShenandoahPhaseTimings::phase_name(ShenandoahGCPhase::current_phase()));

}

ShenandoahWorkerSession::~ShenandoahWorkerSession() {

#ifdef ASSERT

  Thread* thr = Thread::current();

  assert(ShenandoahThreadLocalData::worker_id(thr) != ShenandoahThreadLocalData::INVALID_WORKER_ID, "Must be set");

  ShenandoahThreadLocalData::set_worker_id(thr, ShenandoahThreadLocalData::INVALID_WORKER_ID);

#endif

}