Navigation Menu

Skip to content

Commit

Permalink
8270110: Shenandoah: Add test for JDK-8269661
Browse files Browse the repository at this point in the history
Backport-of: 548bb3119cf792bb1e65e15e990a4addc9155312
  • Loading branch information
shipilev committed Sep 9, 2021
1 parent c96cfed commit d561554
Show file tree
Hide file tree
Showing 3 changed files with 208 additions and 1 deletion.
5 changes: 4 additions & 1 deletion src/hotspot/share/gc/shenandoah/shenandoahHeap.cpp
Expand Up @@ -1926,7 +1926,10 @@ oop ShenandoahHeap::pin_object(JavaThread* thr, oop o) {
}

void ShenandoahHeap::unpin_object(JavaThread* thr, oop o) {
heap_region_containing(o)->record_unpin();
ShenandoahHeapRegion* r = heap_region_containing(o);
assert(r != NULL, "Sanity");
assert(r->pin_count() > 0, "Region " SIZE_FORMAT " should have non-zero pins", r->index());
r->record_unpin();
}

void ShenandoahHeap::sync_pinned_region_status() {
Expand Down
166 changes: 166 additions & 0 deletions test/hotspot/jtreg/gc/shenandoah/jni/TestStringCriticalWithDedup.java
@@ -0,0 +1,166 @@
/*
* Copyright (c) 2021, Red Hat, Inc. All rights reserved.
*
* 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 TestStringCriticalWithDedup
* @summary Test string deduplication should not cause string critical to crash VM
* @requires vm.gc.Shenandoah
* @modules java.base/java.lang:open
*
* @run main/othervm/native -XX:+UnlockDiagnosticVMOptions -XX:+UnlockExperimentalVMOptions -Xmx512m
* -XX:+UseShenandoahGC -XX:ShenandoahGCMode=passive -XX:+UseStringDeduplication -XX:-CompactStrings
* -XX:+ShenandoahVerify -XX:+ShenandoahDegeneratedGC -XX:ShenandoahTargetNumRegions=4096
* TestStringCriticalWithDedup
*
* @run main/othervm/native -XX:+UnlockDiagnosticVMOptions -XX:+UnlockExperimentalVMOptions -Xmx512m
* -XX:+UseShenandoahGC -XX:ShenandoahGCMode=passive -XX:+UseStringDeduplication -XX:-CompactStrings
* -XX:+ShenandoahVerify -XX:-ShenandoahDegeneratedGC -XX:ShenandoahTargetNumRegions=4096
* TestStringCriticalWithDedup
*/

/* @test TestPinnedGarbage
* @summary Test string deduplication should not cause string critical to crash VM
* @requires vm.gc.Shenandoah
* @modules java.base/java.lang:open
*
* @run main/othervm/native -XX:+UnlockDiagnosticVMOptions -XX:+UnlockExperimentalVMOptions -Xmx512m
* -XX:+UseShenandoahGC -XX:ShenandoahGCHeuristics=aggressive -XX:+UseStringDeduplication -XX:-CompactStrings
* -XX:ShenandoahTargetNumRegions=4096
* TestStringCriticalWithDedup
*
* @run main/othervm/native -XX:+UnlockDiagnosticVMOptions -XX:+UnlockExperimentalVMOptions -Xmx256m
* -XX:+UseShenandoahGC -XX:+UseStringDeduplication -XX:-CompactStrings
* -XX:ShenandoahTargetNumRegions=4096 -XX:+ShenandoahVerify
* TestStringCriticalWithDedup
*/

import java.util.List;
import java.util.ArrayList;
import java.util.concurrent.*;
import java.lang.reflect.*;

public class TestStringCriticalWithDedup {
private static Field valueField;

static {
System.loadLibrary("TestStringCriticalWithDedup");
try {
valueField = String.class.getDeclaredField("value");
valueField.setAccessible(true);
} catch (Exception e) {
throw new RuntimeException(e);
}
}

private static final int NUM_RUNS = 100;
private static final int STRING_COUNT = 1 << 16;
private static final int LITTLE_GARBAGE_COUNT = 1 << 5;
private static final int PINNED_STRING_COUNT = 1 << 4;

private static native long pin(String s);
private static native void unpin(String s, long p);


private static volatile MyClass sink;
public static void main(String[] args) {
ThreadLocalRandom rng = ThreadLocalRandom.current();
for (int i = 0; i < NUM_RUNS; i++) {
test(rng);
}
}

private static Object getValue(String string) {
try {
return valueField.get(string);
} catch (Exception e) {
throw new RuntimeException(e);
}
}

private static void pissiblePinString(ThreadLocalRandom rng, List<Tuple> pinnedList, String s) {
int oneInCounter = STRING_COUNT / PINNED_STRING_COUNT;
if (rng.nextInt(oneInCounter) == 1) {
long v = pin(s);
Object value = getValue(s);
pinnedList.add(new Tuple(s, value, v));
}
}

private static void test(ThreadLocalRandom rng) {
String[] strArray = new String[STRING_COUNT];
List<Tuple> pinnedStrings = new ArrayList<>(PINNED_STRING_COUNT);
for (int i = 0; i < STRING_COUNT; i++) {
// Create some garbage inbetween, so strings can be scattered in
// different regions
createLittleGarbage(rng);

strArray[i] = new String("Hello" + (i % 10));
pissiblePinString(rng, pinnedStrings, strArray[i]);
}

// Let deduplication thread to run a bit
try {
Thread.sleep(10);
} catch(Exception e) {
}

for (int i = 0; i < pinnedStrings.size(); i ++) {
Tuple p = pinnedStrings.get(i);
String s = p.getString();
if (getValue(s) != p.getValue()) {
System.out.println(getValue(s) + " != " + p.getValue());
throw new RuntimeException("String value should be pinned");
}
unpin(p.getString(), p.getValuePointer());
}
}

private static void createLittleGarbage(ThreadLocalRandom rng) {
int count = rng.nextInt(LITTLE_GARBAGE_COUNT);
for (int index = 0; index < count; index ++) {
sink = new MyClass();
}
}

private static class Tuple {
String s;
Object value;
long valuePointer;
public Tuple(String s, Object value, long vp) {
this.s = s;
this.value = value;
this.valuePointer = vp;
}

public String getString() {
return s;
}
public Object getValue() { return value; }
public long getValuePointer() {
return valuePointer;
}
}

private static class MyClass {
public long[] payload = new long[10];
}
}
@@ -0,0 +1,38 @@
/*
* Copyright (c) 2021, Red Hat, Inc. All rights reserved.
*
* 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.
*
*/

#include <jni.h>
#include <string.h>
#include <stdint.h>

JNIEXPORT jlong JNICALL
Java_TestStringCriticalWithDedup_pin(JNIEnv *env, jclass unused, jstring s) {
const jchar* a = (*env)->GetStringCritical(env, s, NULL);
return (jlong)(uintptr_t)a;
}

JNIEXPORT void JNICALL
Java_TestStringCriticalWithDedup_unpin(JNIEnv *env, jclass unused, jstring s, jlong v) {
jchar* a = (jchar*)(uintptr_t)v;
(*env)->ReleaseStringCritical(env, s, a);
}

1 comment on commit d561554

@openjdk-notifier
Copy link

Choose a reason for hiding this comment

The reason will be displayed to describe this comment to others. Learn more.

Please sign in to comment.