/*
    * Copyright 2017 The Netty Project
    *
    * The Netty Project licenses this file to you under the Apache License,
    * version 2.0 (the "License"); you may not use this file except in compliance
    * with the License. You may obtain a copy of the License at:
    *
    *   https://www.apache.org/licenses/LICENSE-2.0
    *
   * Unless required by applicable law or agreed to in writing, software
   * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
   * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
   * License for the specific language governing permissions and limitations
   * under the License.
   */
  package io.netty.buffer;
  
  import io.netty.microbench.util.AbstractMicrobenchmark;
  import org.openjdk.jmh.annotations.Benchmark;
  import org.openjdk.jmh.annotations.BenchmarkMode;
  import org.openjdk.jmh.annotations.CompilerControl;
  import org.openjdk.jmh.annotations.GroupThreads;
  import org.openjdk.jmh.annotations.Mode;
  import org.openjdk.jmh.annotations.OutputTimeUnit;
  import org.openjdk.jmh.annotations.Param;
  import org.openjdk.jmh.annotations.Scope;
  import org.openjdk.jmh.annotations.Setup;
  import org.openjdk.jmh.annotations.State;
  import org.openjdk.jmh.annotations.TearDown;
  import org.openjdk.jmh.infra.Blackhole;
  
  import java.util.concurrent.TimeUnit;
  
  @State(Scope.Benchmark)
  public class AbstractReferenceCountedByteBufBenchmark extends AbstractMicrobenchmark {
  
      @Param({
              "0",
              "1",
              "10",
              "100",
              "1000",
              "10000",
      })
      public int delay;
  
      AbstractReferenceCountedByteBuf buf;
  
      @Setup
      public void setUp() {
          buf = (AbstractReferenceCountedByteBuf) Unpooled.buffer(1);
      }
  
      @TearDown
      public void tearDown() {
          buf.release();
      }
  
      @Benchmark
      @BenchmarkMode(Mode.AverageTime)
      @OutputTimeUnit(TimeUnit.NANOSECONDS)
      public boolean retainReleaseUncontended() {
          buf.retain();
          delay();
          return buf.release();
      }
  
      private void delay() {
          if (delay > 0) {
              Blackhole.consumeCPU(delay);
          }
      }
  
      @Benchmark
      @BenchmarkMode(Mode.AverageTime)
      @OutputTimeUnit(TimeUnit.NANOSECONDS)
      @CompilerControl(CompilerControl.Mode.DONT_INLINE)
      public boolean createUseAndRelease(Blackhole useBuffer) {
          ByteBuf unpooled = Unpooled.buffer(1);
          useBuffer.consume(unpooled);
          delay();
          return unpooled.release();
      }
  
      @Benchmark
      @BenchmarkMode(Mode.AverageTime)
      @OutputTimeUnit(TimeUnit.NANOSECONDS)
      @GroupThreads(4)
      public boolean retainReleaseContended() {
          buf.retain();
          delay();
          return buf.release();
      }
  }