8245194: Unix domain socket channel implementation

Reviewed-by: erikj, dfuchs, alanb, chegar

test/micro/org/openjdk/bench/java/net/UnixSocketChannelReadWrite.java

@@ -0,0 +1,124 @@
+/*
+ * Copyright (c) 2020 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.
+ */
+package org.openjdk.bench.java.net;
+
+import java.io.IOException;
+import java.net.StandardProtocolFamily;
+import java.net.UnixDomainSocketAddress;
+import java.nio.ByteBuffer;
+import java.nio.channels.ClosedChannelException;
+import java.nio.channels.ServerSocketChannel;
+import java.nio.channels.SocketChannel;
+import java.nio.file.*;
+import java.util.concurrent.TimeUnit;
+import java.util.concurrent.atomic.AtomicInteger;
+
+import org.openjdk.jmh.annotations.*;
+
+/**
+ * Tests the overheads of I/O API.
+ * This test is known to depend heavily on network conditions and paltform.
+ */
+@BenchmarkMode(Mode.Throughput)
+@OutputTimeUnit(TimeUnit.MILLISECONDS)
+@State(Scope.Thread)
+public class UnixSocketChannelReadWrite {
+
+    private ServerSocketChannel ssc;
+    private SocketChannel s1, s2;
+    private ReadThread rt;
+    private ByteBuffer bb = ByteBuffer.allocate(1);
+
+    private static volatile String tempDir;
+    private static final AtomicInteger count = new AtomicInteger(0);
+    private volatile Path socket;
+
+    static {
+        try {
+            Path p = Files.createTempDirectory("readWriteTest");
+            tempDir = p.toString();
+        } catch (IOException e) {
+            tempDir = null;
+        }
+    }
+
+    private ServerSocketChannel getServerSocketChannel() throws IOException {
+        int next = count.incrementAndGet();
+        socket = Paths.get(tempDir, Integer.toString(next));
+        UnixDomainSocketAddress addr = UnixDomainSocketAddress.of(socket);
+        ServerSocketChannel c = ServerSocketChannel.open(StandardProtocolFamily.UNIX);
+        c.bind(addr);
+        return c;
+    }
+
+    @Setup(Level.Trial)
+    public void beforeRun() throws IOException {
+        ssc = getServerSocketChannel();
+        s1 = SocketChannel.open(ssc.getLocalAddress());
+        s2 = ssc.accept();
+
+        rt = new ReadThread(s2);
+        rt.start();
+
+        bb.put((byte) 47);
+        bb.flip();
+    }
+
+    @TearDown(Level.Trial)
+    public void afterRun() throws IOException, InterruptedException {
+        s1.close();
+        s2.close();
+        ssc.close();
+        Files.delete(socket);
+        Files.delete(Path.of(tempDir));
+        rt.join();
+    }
+
+    @Benchmark
+    public void test() throws IOException {
+        s1.write(bb);
+        bb.flip();
+    }
+
+    static class ReadThread extends Thread {
+        private SocketChannel sc;
+
+        public ReadThread(SocketChannel s2) {
+            this.sc = s2;
+        }
+
+        public void run() {
+            try {
+                ByteBuffer bb = ByteBuffer.allocate(1);
+                while (sc.read(bb) > 0) {
+                    bb.flip();
+                }
+            } catch (ClosedChannelException ex) {
+                // shutdown time
+            } catch (IOException e) {
+                e.printStackTrace();
+            }
+        }
+    }
+
+}