/*
 * Copyright (c) 2014, 2015, Dynatrace and/or its affiliates. All rights reserved.
 *
 * This file is part of the Lock Contention Tracing Subsystem for the HotSpot
 * Virtual Machine, which is developed at Christian Doppler Laboratory on
 * Monitoring and Evolution of Very-Large-Scale Software Systems. Please
 * contact us at <http://mevss.jku.at/> if you need additional information
 * or have any questions.
 *
 * 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, see <http://www.gnu.org/licenses/>.
 *
 */

#ifndef SHARE_VM_EVTRACE_TRACEMANAGER_INLINE_HPP
#define SHARE_VM_EVTRACE_TRACEMANAGER_INLINE_HPP

#include "evtrace/traceBuffer.hpp"
#include "evtrace/traceBufferQueue.hpp"
#include "evtrace/traceMetadata.hpp"

inline bool TraceManager::is_initialized() {
  return _is_initialized;
}

inline void TraceManager::assert_initialized() {
  assert(_is_initialized, "not initialized");
  assert(_free_queue != NULL || !EnableEventTracingBufferReuse, "freeQueue not initialized");
  assert(_flush_queue != NULL, "flushQueue not initialized");
}

inline TraceBuffer *TraceManager::allocate_buffer() {
  // tradeoff: small buffer sizes reduce the time it takes to process a
  // buffer and make it available again, but cause more queue operations
  // (and possible contentions). large buffers are wasteful for short-lived
  // threads, but cause less queue contention and reclaim operations
  // waiting for buffers to be processed can take significantly longer.
  size_t capacity = EventTracingBufferCapacity;
  if (EnableEventTracingRandomizedBufferCapacity) {
    // use random buffer sizes to avoid that threads which do similar work
    // submit and request buffers all at once
    capacity = round_to(capacity / 2 + ((size_t) os::random()) % capacity, 128);
  }
  TraceBuffer *buffer = new (capacity) TraceBuffer(capacity);
  if (EnableEventTracingDiagnostics) {
    Atomic::inc_ptr(&_allocated_buffer_count);
    jlong count = Atomic::add_ptr(1, &_buffer_count);
    jlong max;
    do {
      max = _max_buffer_count;
    } while (count > max && Atomic::cmpxchg(count, &_max_buffer_count, max) != max);
  }
  return buffer;
}

inline void TraceManager::free_buffer(TraceBuffer *buffer) {
  assert(buffer != NULL, "sanity");
  delete buffer;

  if (EnableEventTracingDiagnostics) {
    Atomic::dec_ptr(&_buffer_count);
  }
}

inline TraceBuffer *TraceManager::request_buffer() {
  assert_initialized();

  TraceBuffer *buffer = NULL;
  if (EnableEventTracingBufferReuse) {
    buffer = _free_queue->try_dequeue();
  }
  if (buffer == NULL) {
    buffer = allocate_buffer();
  }
  return buffer;
}

inline void TraceManager::pre_submit_buffer(TraceBuffer *buffer) {
  assert(buffer != NULL, "no buffer given");
  assert(buffer->owner_id == 0, "must not be set at this point");
  buffer->owner_id = _metadata->thread_id(buffer->owner);
  buffer->owner = NULL;
}

inline void TraceManager::submit_buffer(TraceBuffer *buffer) {
  assert_initialized();
  assert(buffer != NULL, "buffer is NULL");

  TraceManager::pre_submit_buffer(buffer);
  size_t bytes = buffer->filled_size();
  _flush_queue->enqueue(buffer);

  if (EnableEventTracingDiagnostics) {
    Atomic::add(bytes, &_submitted_trace_bytes);
  }
}

inline TraceMetadata *TraceManager::metadata() {
  assert_initialized();
  return _metadata;
}

inline void TraceManager::update_stack_trace_stats(bool truncated, intptr_t total_frames, intptr_t memento_frames) {
  assert_initialized();
  if (EnableEventTracingDiagnostics) {
    assert(total_frames > 0 && memento_frames >= 0, "sanity");
    Atomic::inc_ptr(&_total_stack_traces);
    if (truncated) {
      Atomic::inc_ptr(&_truncated_stack_traces);
    }
    Atomic::add_ptr(total_frames, &_total_stack_frames);
    if (memento_frames != 0) {
      assert(memento_frames < total_frames, "sanity");
      Atomic::inc_ptr(&_reused_memento_stack_traces);
      Atomic::add_ptr(memento_frames, &_reused_memento_stack_frames);
    }
  }
}

#endif /* SHARE_VM_EVTRACE_TRACEMANAGER_INLINE_HPP */