8205608: Fix 'frames()' in ThreadReferenceImpl.c to prevent quadratic runtime behavior
authorsimonis
Mon, 23 Jul 2018 15:17:14 +0200
changeset 51248 21ce0a9e592a
parent 51247 13e816d02c25
child 51249 3fe0329588b8
8205608: Fix 'frames()' in ThreadReferenceImpl.c to prevent quadratic runtime behavior Reviewed-by: sspitsyn, cjplummer
src/jdk.jdwp.agent/share/native/libjdwp/ThreadReferenceImpl.c
test/jdk/com/sun/jdi/Frames2Test.java
--- a/src/jdk.jdwp.agent/share/native/libjdwp/ThreadReferenceImpl.c	Thu Jul 26 14:15:24 2018 +0530
+++ b/src/jdk.jdwp.agent/share/native/libjdwp/ThreadReferenceImpl.c	Mon Jul 23 15:17:14 2018 +0200
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 1998, 2008, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 1998, 2018, 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
@@ -214,12 +214,14 @@
 frames(PacketInputStream *in, PacketOutputStream *out)
 {
     jvmtiError error;
-    FrameNumber fnum;
+    FrameNumber index;
     jint count;
+    jint filledIn;
     JNIEnv *env;
     jthread thread;
     jint startIndex;
     jint length;
+    jvmtiFrameInfo* frames;
 
     env = getEnv();
 
@@ -273,37 +275,37 @@
 
     (void)outStream_writeInt(out, length);
 
-    for(fnum = startIndex ; fnum < startIndex+length ; fnum++ ) {
+    frames = jvmtiAllocate(sizeof(jvmtiFrameInfo) * length);
 
-        WITH_LOCAL_REFS(env, 1) {
+    if (frames == NULL) {
+        outStream_setError(out, JDWP_ERROR(OUT_OF_MEMORY));
+        return JNI_TRUE;
+    }
 
-            jclass clazz;
-            jmethodID method;
-            jlocation location;
+    error = JVMTI_FUNC_PTR(gdata->jvmti, GetStackTrace)
+                          (gdata->jvmti, thread, startIndex, length, frames,
+                           &filledIn);
+
+    /* Should not happen. */
+    if (error == JVMTI_ERROR_NONE && length != filledIn) {
+        error = JVMTI_ERROR_INTERNAL;
+    }
 
-            /* Get location info */
-            error = JVMTI_FUNC_PTR(gdata->jvmti,GetFrameLocation)
-                (gdata->jvmti, thread, fnum, &method, &location);
-            if (error == JVMTI_ERROR_OPAQUE_FRAME) {
-                clazz = NULL;
-                location = -1L;
-                error = JVMTI_ERROR_NONE;
-            } else if ( error == JVMTI_ERROR_NONE ) {
-                error = methodClass(method, &clazz);
-                if ( error == JVMTI_ERROR_NONE ) {
-                    FrameID frame;
-                    frame = createFrameID(thread, fnum);
-                    (void)outStream_writeFrameID(out, frame);
-                    writeCodeLocation(out, clazz, method, location);
-                }
+    for (index = 0; index < filledIn && error == JVMTI_ERROR_NONE; ++index) {
+        WITH_LOCAL_REFS(env, 1) {
+            jclass clazz;
+            error = methodClass(frames[index].method, &clazz);
+
+            if (error == JVMTI_ERROR_NONE) {
+                FrameID frame = createFrameID(thread, index + startIndex);
+                outStream_writeFrameID(out, frame);
+                writeCodeLocation(out, clazz, frames[index].method,
+                                  frames[index].location);
             }
-
         } END_WITH_LOCAL_REFS(env);
+    }
 
-        if (error != JVMTI_ERROR_NONE)
-            break;
-
-    }
+    jvmtiDeallocate(frames);
 
     if (error != JVMTI_ERROR_NONE) {
         outStream_setError(out, map2jdwpError(error));
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/test/jdk/com/sun/jdi/Frames2Test.java	Mon Jul 23 15:17:14 2018 +0200
@@ -0,0 +1,150 @@
+/*
+ * Copyright (c) 2018, 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 8205608
+ * @summary Test that getting the stack trace for a very large stack does
+ * not take too long
+ *
+ * @author Ralf Schmelter
+ *
+ * @run build TestScaffold VMConnection TargetListener TargetAdapter
+ * @run compile -g Frames2Test.java
+ * @run driver Frames2Test -Xss4M
+ */
+import com.sun.jdi.*;
+import com.sun.jdi.event.*;
+import com.sun.jdi.request.*;
+
+import java.util.*;
+import java.util.stream.*;
+
+
+    /********** target program **********/
+
+class Frames2Targ {
+
+    public static void main(String[] args) {
+        recurse(1_000_000);
+    }
+
+    static void notifyRecursionEnded() {
+        // We moved this to a method instead of doing it directly in the
+        // exception handler for the StackOverflowError, since we don't
+        // need to know the line number (which might change later) when
+        // requesting the breakpoint. Additionally this method is
+        // used as a marker method to check for the correct top of stack
+        // in the stack trace queried by JDI.
+        System.out.println("SOE occurred as expected");
+    }
+
+    static int recurse(int depth) {
+        if (depth == 0) {
+            // Should have seen a stack overflow by now.
+            System.out.println("Exited without creating SOE");
+            System.exit(0);
+        }
+
+        try {
+            int newDepth = recurse(depth - 1);
+
+            if (newDepth == -1_000) {
+                // Pop some frames so there is room on the stack for the
+                // call (including println()).
+                notifyRecursionEnded();
+            }
+
+            return newDepth - 1;
+        } catch (StackOverflowError e) {
+            // Use negative depth to indicate the recursion has ended.
+            return -1;
+        }
+    }
+}
+
+    /********** test program **********/
+
+public class Frames2Test extends TestScaffold {
+
+    public Frames2Test(String args[]) {
+        super(args);
+    }
+
+    public static void main(String[] args) throws Exception {
+        new Frames2Test(args).startTests();
+    }
+
+
+    /********** test core **********/
+
+    protected void runTests() throws Exception {
+        BreakpointEvent bpe = startToMain("Frames2Targ");
+        List<Method> frames1 = bpe.thread().frames().stream().map(
+                StackFrame::location).map(Location::method).
+                collect(Collectors.toList());
+
+        bpe = resumeTo("Frames2Targ", "notifyRecursionEnded", "()V");
+        List<Method> frames2 = bpe.thread().frames().stream().map(
+                StackFrame::location).map(Location::method).
+                collect(Collectors.toList());
+        System.out.println("Got stack of " + frames2.size() + " frames");
+
+        // Check that the stack looks as follows:
+        // notifyRecursionEnded()
+        // recurse()
+        // ....
+        // recurse()
+        // main()
+        // <whatever the VM likes to add>
+
+        // Check the bottom of the stack.
+        for (int i = 0; i < frames1.size(); ++i) {
+            int i2 = frames2.size() - frames1.size() + i;
+            if (!frames1.get(i).equals(frames2.get(i2))) {
+                failure("Bottom methods do not match: " +
+                        frames1.get(i) + " vs " + frames2.get(i2));
+            }
+        }
+
+        // Check the recurse() calls on the stack.
+        for (int i = 1; i < frames2.size() - frames1.size(); ++i) {
+            if (!frames2.get(i).name().equals("recurse")) {
+                failure("Expected recurse() but got " + frames2.get(i));
+            }
+        }
+
+        // Check the top method of the stack.
+        if (!frames2.get(0).name().equals("notifyRecursionEnded")) {
+            failure("Expected notifyRecursionEnded() but got " + frames2.get(0));
+        }
+
+        listenUntilVMDisconnect();
+
+        if (!testFailed) {
+            println("Frames2Test: passed");
+        } else {
+            throw new Exception("Frames2Test: failed");
+        }
+    }
+}