changeset 57285:ca70299778b9

8205132: Degrade Thread.countStackFrames() to throw UOE Reviewed-by: mchung, dholmes, dcubed
author alanb
date Thu, 31 Oct 2019 16:45:58 +0000
parents 27c2d2a4b695
children 5f1fe5971ff9
files make/hotspot/symbols/symbols-unix src/hotspot/share/include/jvm.h src/hotspot/share/prims/jvm.cpp src/java.base/share/classes/java/lang/Thread.java src/java.base/share/native/libjava/Thread.c test/hotspot/jtreg/runtime/Thread/CountStackFramesAtExit.java test/jdk/java/lang/Thread/CountStackFrames.java
diffstat 7 files changed, 66 insertions(+), 170 deletions(-) [+]
line wrap: on
line diff
--- a/make/hotspot/symbols/symbols-unix	Mon Oct 28 15:03:36 2019 +0100
+++ b/make/hotspot/symbols/symbols-unix	Thu Oct 31 16:45:58 2019 +0000
@@ -46,7 +46,6 @@
 JVM_ConstantPoolGetStringAt
 JVM_ConstantPoolGetTagAt
 JVM_ConstantPoolGetUTF8At
-JVM_CountStackFrames
 JVM_CurrentThread
 JVM_CurrentTimeMillis
 JVM_DefineClass
--- a/src/hotspot/share/include/jvm.h	Mon Oct 28 15:03:36 2019 +0100
+++ b/src/hotspot/share/include/jvm.h	Thu Oct 31 16:45:58 2019 +0000
@@ -248,9 +248,6 @@
 JNIEXPORT jobject JNICALL
 JVM_CurrentThread(JNIEnv *env, jclass threadClass);
 
-JNIEXPORT jint JNICALL
-JVM_CountStackFrames(JNIEnv *env, jobject thread);
-
 JNIEXPORT void JNICALL
 JVM_Interrupt(JNIEnv *env, jobject thread);
 
--- a/src/hotspot/share/prims/jvm.cpp	Mon Oct 28 15:03:36 2019 +0100
+++ b/src/hotspot/share/prims/jvm.cpp	Thu Oct 31 16:45:58 2019 +0000
@@ -3052,50 +3052,6 @@
   return JNIHandles::make_local(env, jthread);
 JVM_END
 
-class CountStackFramesTC : public ThreadClosure {
-  int _count;
-  bool _suspended;
- public:
-  CountStackFramesTC() : _count(0), _suspended(false) {}
-  virtual void do_thread(Thread* thread) {
-    JavaThread* jt = (JavaThread*)thread;
-    if (!jt->is_external_suspend()) {
-      // To keep same behavior we fail this operation,
-      // even if it would work perfectly.
-      return;
-    }
-    _suspended = true;
-     // Count all java activation, i.e., number of vframes.
-    for (vframeStream vfst(jt); !vfst.at_end(); vfst.next()) {
-      // Native frames are not counted.
-      if (!vfst.method()->is_native()) _count++;
-    }
-  }
-  int count() { return _count; }
-  int suspended() { return _suspended; }
-};
-
-JVM_ENTRY(jint, JVM_CountStackFrames(JNIEnv* env, jobject jthread))
-  JVMWrapper("JVM_CountStackFrames");
-
-  ThreadsListHandle tlh(thread);
-  JavaThread* receiver = NULL;
-  bool is_alive = tlh.cv_internal_thread_to_JavaThread(jthread, &receiver, NULL);
-  if (is_alive) {
-    // jthread refers to a live JavaThread.
-    CountStackFramesTC csf;
-    Handshake::execute(&csf, receiver);
-    if (!csf.suspended()) {
-      THROW_MSG_0(vmSymbols::java_lang_IllegalThreadStateException(),
-                  "this thread is not suspended");
-    }
-    return csf.count();
-  }
-  // Implied else: if JavaThread is not alive simply return a count of 0.
-  return 0;
-JVM_END
-
-
 JVM_ENTRY(void, JVM_Interrupt(JNIEnv* env, jobject jthread))
   JVMWrapper("JVM_Interrupt");
 
--- a/src/java.base/share/classes/java/lang/Thread.java	Mon Oct 28 15:03:36 2019 +0100
+++ b/src/java.base/share/classes/java/lang/Thread.java	Thu Oct 31 16:45:58 2019 +0000
@@ -1251,20 +1251,20 @@
     }
 
     /**
-     * Counts the number of stack frames in this thread. The thread must
-     * be suspended.
+     * Throws {@code UnsupportedOperationException}.
      *
-     * @return     the number of stack frames in this thread.
-     * @throws     IllegalThreadStateException  if this thread is not
-     *             suspended.
-     * @deprecated The definition of this call depends on {@link #suspend},
-     *             which is deprecated.  Further, the results of this call
-     *             were never well-defined.
+     * @return     nothing
+     *
+     * @deprecated This method was originally designed to count the number of
+     *             stack frames but the results were never well-defined and it
+     *             depended on thread-suspension.
      *             This method is subject to removal in a future version of Java SE.
      * @see        StackWalker
      */
     @Deprecated(since="1.2", forRemoval=true)
-    public native int countStackFrames();
+    public int countStackFrames() {
+        throw new UnsupportedOperationException();
+    }
 
     /**
      * Waits at most {@code millis} milliseconds for this thread to
--- a/src/java.base/share/native/libjava/Thread.c	Mon Oct 28 15:03:36 2019 +0100
+++ b/src/java.base/share/native/libjava/Thread.c	Thu Oct 31 16:45:58 2019 +0000
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 1994, 2012, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 1994, 2019, 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
@@ -50,7 +50,6 @@
     {"yield",            "()V",        (void *)&JVM_Yield},
     {"sleep",            "(J)V",       (void *)&JVM_Sleep},
     {"currentThread",    "()" THD,     (void *)&JVM_CurrentThread},
-    {"countStackFrames", "()I",        (void *)&JVM_CountStackFrames},
     {"interrupt0",       "()V",        (void *)&JVM_Interrupt},
     {"isInterrupted",    "(Z)Z",       (void *)&JVM_IsInterrupted},
     {"holdsLock",        "(" OBJ ")Z", (void *)&JVM_HoldsLock},
--- a/test/hotspot/jtreg/runtime/Thread/CountStackFramesAtExit.java	Mon Oct 28 15:03:36 2019 +0100
+++ /dev/null	Thu Jan 01 00:00:00 1970 +0000
@@ -1,111 +0,0 @@
-/*
- * Copyright (c) 2017, 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
- * @bug 8167108
- * @summary Stress test java.lang.Thread.countStackFrames() at thread exit.
- * @run main/othervm -Xlog:thread+smr=debug CountStackFramesAtExit
- */
-
-import java.util.concurrent.CountDownLatch;
-
-public class CountStackFramesAtExit extends Thread {
-    final static int N_THREADS = 32;
-    final static int N_LATE_CALLS = 1000;
-
-    public CountDownLatch exitSyncObj = new CountDownLatch(1);
-    public CountDownLatch startSyncObj = new CountDownLatch(1);
-
-    @Override
-    public void run() {
-        // Tell main thread we have started.
-        startSyncObj.countDown();
-        try {
-            // Wait for main thread to interrupt us so we
-            // can race to exit.
-            exitSyncObj.await();
-        } catch (InterruptedException e) {
-            // ignore because we expect one
-        }
-    }
-
-    public static void main(String[] args) {
-        CountStackFramesAtExit threads[] = new CountStackFramesAtExit[N_THREADS];
-
-        for (int i = 0; i < N_THREADS; i++ ) {
-            threads[i] = new CountStackFramesAtExit();
-            int late_count = 1;
-            threads[i].start();
-            try {
-                // Wait for the worker thread to get going.
-                threads[i].startSyncObj.await();
-
-                // This interrupt() call will break the worker out of
-                // the exitSyncObj.await() call and the countStackFrames()
-                // calls will come in during thread exit.
-                threads[i].interrupt();
-                for (; late_count <= N_LATE_CALLS; late_count++) {
-                    try {
-                        threads[i].countStackFrames();
-                    } catch (IllegalThreadStateException itse) {
-                        // ignore because we expect it
-                    }
-
-                    if (!threads[i].isAlive()) {
-                        // Done with Thread.countStackFrames() calls since
-                        // thread is not alive.
-                        break;
-                    }
-                }
-            } catch (InterruptedException e) {
-                throw new Error("Unexpected: " + e);
-            }
-
-            System.out.println("INFO: thread #" + i + ": made " + late_count +
-                               " late calls to java.lang.Thread.countStackFrames()");
-            System.out.println("INFO: thread #" + i + ": N_LATE_CALLS==" +
-                               N_LATE_CALLS + " value is " +
-                               ((late_count >= N_LATE_CALLS) ? "NOT " : "") +
-                               "large enough to cause a Thread.countStackFrames() " +
-                               "call after thread exit.");
-
-            try {
-                threads[i].join();
-            } catch (InterruptedException e) {
-                throw new Error("Unexpected: " + e);
-            }
-            threads[i].countStackFrames();
-            if (threads[i].isAlive()) {
-                throw new Error("Expected !Thread.isAlive() after thread #" +
-                                i + " has been join()'ed");
-            }
-        }
-
-        String cmd = System.getProperty("sun.java.command");
-        if (cmd != null && !cmd.startsWith("com.sun.javatest.regtest.agent.MainWrapper")) {
-            // Exit with success in a non-JavaTest environment:
-            System.exit(0);
-        }
-    }
-}
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/test/jdk/java/lang/Thread/CountStackFrames.java	Thu Oct 31 16:45:58 2019 +0000
@@ -0,0 +1,56 @@
+/*
+ * Copyright (c) 2019, 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
+ * @bug 8205132
+ * @summary Test Thread.countStackFrames()
+ * @run testng CountStackFrames
+ */
+
+import org.testng.annotations.Test;
+
+public class CountStackFrames {
+
+    // current thread
+    @Test(expectedExceptions = UnsupportedOperationException.class)
+    public void testCurrentThread() {
+        Thread.currentThread().countStackFrames();
+    }
+
+    // unstarted thread
+    @Test(expectedExceptions = UnsupportedOperationException.class)
+    public void testUnstartedThread() {
+        Thread thread = new Thread(() -> { });
+        thread.countStackFrames();
+    }
+
+    // terminated thread
+    @Test(expectedExceptions = UnsupportedOperationException.class)
+    public void testTerminatedThread() throws Exception {
+        Thread thread = new Thread(() -> { });
+        thread.start();
+        thread.join();
+        thread.countStackFrames();
+    }
+
+}