8323782: Race: Thread::interrupt vs. AbstractInterruptibleChannel.begin

Co-authored-by: Alan Bateman <alanb@openjdk.org>
Reviewed-by: alanb, dholmes

src/java.base/share/classes/java/lang/Thread.java

@@ -1702,24 +1702,25 @@ public class Thread implements Runnable {
     public void interrupt() {
         if (this != Thread.currentThread()) {
             checkAccess();
+        }
 
-            // thread may be blocked in an I/O operation
+        // Setting the interrupt status must be done before reading nioBlocker.
+        interrupted = true;
+        interrupt0();  // inform VM of interrupt
+
+        // thread may be blocked in an I/O operation
+        if (this != Thread.currentThread()) {
             Interruptible blocker;
             synchronized (interruptLock) {
                 blocker = nioBlocker;
                 if (blocker != null) {
-                    interrupted = true;
-                    interrupt0();  // inform VM of interrupt
                     blocker.interrupt(this);
                 }
             }
             if (blocker != null) {
                 blocker.postInterrupt();
-                return;
             }
         }
-        interrupted = true;
-        interrupt0();  // inform VM of interrupt
     }
 
     /**

test/jdk/java/nio/channels/Selector/LotsOfInterrupts.java

@@ -0,0 +1,91 @@
+/*
+ * Copyright (c) 2024, 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.
+ */
+
+/*
+ * @test id=platform
+ * @bug 8323782
+ * @summary Stress test Thread.interrupt on a target Thread doing a selection operation
+ * @run main LotsOfInterrupts 200000
+ */
+
+/*
+ * @test id=virtual
+ * @run main/othervm -DthreadFactory=virtual LotsOfInterrupts 200000
+ */
+
+import java.nio.channels.Selector;
+import java.time.Instant;
+import java.util.concurrent.Phaser;
+import java.util.concurrent.ThreadFactory;
+
+public class LotsOfInterrupts {
+
+    public static void main(String[] args) throws Exception {
+        int iterations;
+        if (args.length > 0) {
+            iterations = Integer.parseInt(args[0]);
+        } else {
+            iterations = 500_000;
+        }
+
+        ThreadFactory factory;
+        String value = System.getProperty("threadFactory");
+        if ("virtual".equals(value)) {
+            factory = Thread.ofVirtual().factory();
+        } else {
+            factory = Thread.ofPlatform().factory();
+        }
+
+        var phaser = new Phaser(2);
+
+        Thread thread = factory.newThread(() -> {
+            try (Selector sel = Selector.open()) {
+                for (int i = 0; i < iterations; i++) {
+                    phaser.arriveAndAwaitAdvance();
+                    sel.select();
+
+                    // clear interrupt status and consume wakeup
+                    Thread.interrupted();
+                    sel.selectNow();
+                }
+            } catch (Throwable ex) {
+                ex.printStackTrace();
+            }
+        });
+        thread.start();
+
+        long lastTimestamp = System.currentTimeMillis();
+        for (int i = 0; i < iterations; i++) {
+            phaser.arriveAndAwaitAdvance();
+            thread.interrupt();
+
+            long currentTime = System.currentTimeMillis();
+            if ((currentTime - lastTimestamp) > 500) {
+                System.out.format("%s %d iterations remaining ...%n", Instant.now(), (iterations - i));
+                lastTimestamp = currentTime;
+            }
+        }
+
+        thread.join();
+    }
+}