8008965: @Contended fails with classes having static fields
Summary: Disable @Contended support for static fields
Reviewed-by: coleenp, kvn
Contributed-by: Aleksey Shipilev <aleksey.shipilev@oracle.com>
--- a/hotspot/src/share/vm/classfile/classFileParser.cpp Fri Mar 08 17:49:52 2013 -0800
+++ b/hotspot/src/share/vm/classfile/classFileParser.cpp Mon Mar 11 14:00:09 2013 -0400
@@ -3492,7 +3492,6 @@
int next_static_word_offset;
int next_static_short_offset;
int next_static_byte_offset;
- int next_static_padded_offset;
int next_nonstatic_oop_offset;
int next_nonstatic_double_offset;
int next_nonstatic_word_offset;
@@ -3505,33 +3504,25 @@
int next_nonstatic_padded_offset;
// Count the contended fields by type.
- int static_contended_count = 0;
int nonstatic_contended_count = 0;
FieldAllocationCount fac_contended;
for (AllFieldStream fs(fields, cp); !fs.done(); fs.next()) {
FieldAllocationType atype = (FieldAllocationType) fs.allocation_type();
if (fs.is_contended()) {
fac_contended.count[atype]++;
- if (fs.access_flags().is_static()) {
- static_contended_count++;
- } else {
+ if (!fs.access_flags().is_static()) {
nonstatic_contended_count++;
}
}
}
- int contended_count = static_contended_count + nonstatic_contended_count;
+ int contended_count = nonstatic_contended_count;
// Calculate the starting byte offsets
next_static_oop_offset = InstanceMirrorKlass::offset_of_static_fields();
- // class is contended, pad before all the fields
- if (parsed_annotations.is_contended()) {
- next_static_oop_offset += pad_size;
- }
-
next_static_double_offset = next_static_oop_offset +
- ((fac.count[STATIC_OOP] - fac_contended.count[STATIC_OOP]) * heapOopSize);
+ ((fac.count[STATIC_OOP]) * heapOopSize);
if ( fac.count[STATIC_DOUBLE] &&
(Universe::field_type_should_be_aligned(T_DOUBLE) ||
Universe::field_type_should_be_aligned(T_LONG)) ) {
@@ -3539,13 +3530,11 @@
}
next_static_word_offset = next_static_double_offset +
- ((fac.count[STATIC_DOUBLE] - fac_contended.count[STATIC_DOUBLE]) * BytesPerLong);
+ ((fac.count[STATIC_DOUBLE]) * BytesPerLong);
next_static_short_offset = next_static_word_offset +
- ((fac.count[STATIC_WORD] - fac_contended.count[STATIC_WORD]) * BytesPerInt);
+ ((fac.count[STATIC_WORD]) * BytesPerInt);
next_static_byte_offset = next_static_short_offset +
- ((fac.count[STATIC_SHORT] - fac_contended.count[STATIC_SHORT]) * BytesPerShort);
- next_static_padded_offset = next_static_byte_offset +
- ((fac.count[STATIC_BYTE] - fac_contended.count[STATIC_BYTE]) * 1);
+ ((fac.count[STATIC_SHORT]) * BytesPerShort);
first_nonstatic_field_offset = instanceOopDesc::base_offset_in_bytes() +
nonstatic_field_size * heapOopSize;
@@ -3738,8 +3727,8 @@
// skip already laid out fields
if (fs.is_offset_set()) continue;
- // contended fields are handled below
- if (fs.is_contended()) continue;
+ // contended instance fields are handled below
+ if (fs.is_contended() && !fs.access_flags().is_static()) continue;
int real_offset;
FieldAllocationType atype = (FieldAllocationType) fs.allocation_type();
@@ -3943,86 +3932,6 @@
// handle static fields
- // if there is at least one contended field, we need to have pre-padding for them
- if (static_contended_count > 0) {
- next_static_padded_offset += pad_size;
- }
-
- current_group = -1;
- while ((current_group = (int)bm.get_next_one_offset(current_group + 1)) != (int)bm.size()) {
-
- for (AllFieldStream fs(fields, cp); !fs.done(); fs.next()) {
-
- // skip already laid out fields
- if (fs.is_offset_set()) continue;
-
- // skip non-contended fields and fields from different group
- if (!fs.is_contended() || (fs.contended_group() != current_group)) continue;
-
- // non-statics already handled above
- if (!fs.access_flags().is_static()) continue;
-
- int real_offset;
- FieldAllocationType atype = (FieldAllocationType) fs.allocation_type();
-
- switch (atype) {
-
- case STATIC_BYTE:
- next_static_padded_offset = align_size_up(next_static_padded_offset, 1);
- real_offset = next_static_padded_offset;
- next_static_padded_offset += 1;
- break;
-
- case STATIC_SHORT:
- next_static_padded_offset = align_size_up(next_static_padded_offset, BytesPerShort);
- real_offset = next_static_padded_offset;
- next_static_padded_offset += BytesPerShort;
- break;
-
- case STATIC_WORD:
- next_static_padded_offset = align_size_up(next_static_padded_offset, BytesPerInt);
- real_offset = next_static_padded_offset;
- next_static_padded_offset += BytesPerInt;
- break;
-
- case STATIC_DOUBLE:
- next_static_padded_offset = align_size_up(next_static_padded_offset, BytesPerLong);
- real_offset = next_static_padded_offset;
- next_static_padded_offset += BytesPerLong;
- break;
-
- case STATIC_OOP:
- next_static_padded_offset = align_size_up(next_static_padded_offset, heapOopSize);
- real_offset = next_static_padded_offset;
- next_static_padded_offset += heapOopSize;
- break;
-
- default:
- ShouldNotReachHere();
- }
-
- if (fs.contended_group() == 0) {
- // Contended group defines the equivalence class over the fields:
- // the fields within the same contended group are not inter-padded.
- // The only exception is default group, which does not incur the
- // equivalence, and so requires intra-padding.
- next_static_padded_offset += pad_size;
- }
-
- fs.set_offset(real_offset);
- } // for
-
- // Start laying out the next group.
- // Note that this will effectively pad the last group in the back;
- // this is expected to alleviate memory contention effects for
- // subclass fields and/or adjacent object.
- // If this was the default group, the padding is already in place.
- if (current_group != 0) {
- next_static_padded_offset += pad_size;
- }
-
- }
-
} // handle contended
// Size of instances
@@ -4035,10 +3944,9 @@
// and/or adjacent object.
if (parsed_annotations.is_contended()) {
notaligned_offset += pad_size;
- next_static_padded_offset += pad_size;
}
- int next_static_type_offset = align_size_up(next_static_padded_offset, wordSize);
+ int next_static_type_offset = align_size_up(next_static_byte_offset, wordSize);
int static_field_size = (next_static_type_offset -
InstanceMirrorKlass::offset_of_static_fields()) / wordSize;
--- /dev/null Thu Jan 01 00:00:00 1970 +0000
+++ b/hotspot/test/runtime/8003985/Test8003985.java Mon Mar 11 14:00:09 2013 -0400
@@ -0,0 +1,302 @@
+/*
+ * Copyright (c) 2013, 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.
+ */
+
+import java.io.BufferedReader;
+import java.io.InputStreamReader;
+import java.lang.Class;
+import java.lang.String;
+import java.lang.System;
+import java.lang.management.ManagementFactory;
+import java.lang.management.RuntimeMXBean;
+import java.util.ArrayList;
+import java.util.List;
+import java.util.concurrent.CyclicBarrier;
+import java.util.regex.Matcher;
+import java.util.regex.Pattern;
+import java.lang.reflect.Field;
+import java.lang.reflect.Modifier;
+import sun.misc.Unsafe;
+import sun.misc.Contended;
+
+/*
+ * @test
+ * @bug 8003985
+ * @summary Support Contended Annotation - JEP 142
+ *
+ * @run main/othervm -XX:-RestrictContended Test8003985
+ */
+public class Test8003985 {
+
+ private static final Unsafe U;
+ private static int ADDRESS_SIZE;
+ private static int HEADER_SIZE;
+
+ static {
+ // steal Unsafe
+ try {
+ Field unsafe = Unsafe.class.getDeclaredField("theUnsafe");
+ unsafe.setAccessible(true);
+ U = (Unsafe) unsafe.get(null);
+ } catch (NoSuchFieldException | IllegalAccessException e) {
+ throw new IllegalStateException(e);
+ }
+
+ // When running with CompressedOops on 64-bit platform, the address size
+ // reported by Unsafe is still 8, while the real reference fields are 4 bytes long.
+ // Try to guess the reference field size with this naive trick.
+ try {
+ long off1 = U.objectFieldOffset(CompressedOopsClass.class.getField("obj1"));
+ long off2 = U.objectFieldOffset(CompressedOopsClass.class.getField("obj2"));
+ ADDRESS_SIZE = (int) Math.abs(off2 - off1);
+ HEADER_SIZE = (int) Math.min(off1, off2);
+ } catch (NoSuchFieldException e) {
+ ADDRESS_SIZE = -1;
+ }
+ }
+
+ static class CompressedOopsClass {
+ public Object obj1;
+ public Object obj2;
+ }
+
+ public static boolean arePaddedPairwise(Class klass, String field1, String field2) throws Exception {
+ Field f1 = klass.getDeclaredField(field1);
+ Field f2 = klass.getDeclaredField(field2);
+
+ if (isStatic(f1) != isStatic(f2)) {
+ return true; // these guys are in naturally disjoint locations
+ }
+
+ int diff = offset(f1) - offset(f2);
+ if (diff < 0) {
+ // f1 is first
+ return (offset(f2) - (offset(f1) + getSize(f1))) > 64;
+ } else {
+ // f2 is first
+ return (offset(f1) - (offset(f2) + getSize(f2))) > 64;
+ }
+ }
+
+ public static boolean isPadded(Class klass, String field1) throws Exception {
+ Field f1 = klass.getDeclaredField(field1);
+
+ if (isStatic(f1)) {
+ return offset(f1) > 128 + 64;
+ }
+
+ return offset(f1) > 64;
+ }
+
+ public static boolean sameLayout(Class klass1, Class klass2) throws Exception {
+ for (Field f1 : klass1.getDeclaredFields()) {
+ Field f2 = klass2.getDeclaredField(f1.getName());
+ if (offset(f1) != offset(f2)) {
+ return false;
+ }
+ }
+
+ for (Field f2 : klass1.getDeclaredFields()) {
+ Field f1 = klass2.getDeclaredField(f2.getName());
+ if (offset(f1) != offset(f2)) {
+ return false;
+ }
+ }
+
+ return true;
+ }
+
+ public static boolean isStatic(Field field) {
+ return Modifier.isStatic(field.getModifiers());
+ }
+
+ public static int offset(Field field) {
+ if (isStatic(field)) {
+ return (int) U.staticFieldOffset(field);
+ } else {
+ return (int) U.objectFieldOffset(field);
+ }
+ }
+
+ public static int getSize(Field field) {
+ Class type = field.getType();
+ if (type == byte.class) { return 1; }
+ if (type == boolean.class) { return 1; }
+ if (type == short.class) { return 2; }
+ if (type == char.class) { return 2; }
+ if (type == int.class) { return 4; }
+ if (type == float.class) { return 4; }
+ if (type == long.class) { return 8; }
+ if (type == double.class) { return 8; }
+ return ADDRESS_SIZE;
+ }
+
+ public static void main(String[] args) throws Exception {
+ boolean endResult = true;
+
+ // --------------- INSTANCE FIELDS ---------------------
+
+ if (arePaddedPairwise(Test1.class, "int1", "int2") ||
+ isPadded(Test1.class, "int1") ||
+ isPadded(Test1.class, "int2")) {
+ System.err.println("Test1 failed");
+ endResult &= false;
+ }
+
+ if (!arePaddedPairwise(Test2.class, "int1", "int2") ||
+ !isPadded(Test2.class, "int1") ||
+ isPadded(Test2.class, "int2")) {
+ System.err.println("Test2 failed");
+ endResult &= false;
+ }
+
+ if (!arePaddedPairwise(Test3.class, "int1", "int2") ||
+ !isPadded(Test3.class, "int1") ||
+ !isPadded(Test3.class, "int2")) {
+ System.err.println("Test3 failed");
+ endResult &= false;
+ }
+
+ if (arePaddedPairwise(Test4.class, "int1", "int2") ||
+ !isPadded(Test4.class, "int1") ||
+ !isPadded(Test4.class, "int2")) {
+ System.err.println("Test4 failed");
+ endResult &= false;
+ }
+
+ if (!arePaddedPairwise(Test5.class, "int1", "int2") ||
+ !isPadded(Test5.class, "int1") ||
+ !isPadded(Test5.class, "int2")) {
+ System.err.println("Test5 failed");
+ endResult &= false;
+ }
+
+ if (!arePaddedPairwise(Test6.class, "int1", "int2") ||
+ !isPadded(Test6.class, "int1") ||
+ !isPadded(Test6.class, "int2")) {
+ System.err.println("Test6 failed");
+ endResult &= false;
+ }
+
+ if (arePaddedPairwise(Test7.class, "int1", "int2") ||
+ !isPadded(Test7.class, "int1") ||
+ !isPadded(Test7.class, "int2")) {
+ System.err.println("Test7 failed");
+ endResult &= false;
+ }
+
+ if (!arePaddedPairwise(Test8.class, "int1", "int2") ||
+ !isPadded(Test8.class, "int1") ||
+ !isPadded(Test8.class, "int2")) {
+ System.err.println("Test8 failed");
+ endResult &= false;
+ }
+
+ if (!arePaddedPairwise(Test9.class, "int1", "int2") ||
+ !isPadded(Test9.class, "int1") ||
+ !isPadded(Test9.class, "int2")) {
+ System.err.println("Test9 failed");
+ endResult &= false;
+ }
+
+ if (!sameLayout(Test4.class, Test7.class)) {
+ System.err.println("Test4 and Test7 have different layouts");
+ endResult &= false;
+ }
+
+ if (!sameLayout(Test5.class, Test6.class)) {
+ System.err.println("Test5 and Test6 have different layouts");
+ endResult &= false;
+ }
+
+ if (!sameLayout(Test8.class, Test9.class)) {
+ System.err.println("Test8 and Test9 have different layouts");
+ endResult &= false;
+ }
+
+ System.out.println(endResult ? "Test PASSES" : "Test FAILS");
+ if (!endResult) {
+ throw new Error("Test failed");
+ }
+ }
+
+ // ----------------------------------- INSTANCE FIELDS -----------------------------------------
+
+ // naturally packed
+ public static class Test1 {
+ private int int1;
+ private int int2;
+ }
+
+ // int1 is padded
+ public static class Test2 {
+ @Contended private int int1;
+ private int int2;
+ }
+
+ // both fields are padded
+ public static class Test3 {
+ @Contended private int int1;
+ @Contended private int int2;
+ }
+
+ // fields are padded in the singular group
+ public static class Test4 {
+ @Contended("sameGroup") private int int1;
+ @Contended("sameGroup") private int int2;
+ }
+
+ // fields are padded in disjoint groups
+ public static class Test5 {
+ @Contended("diffGroup1") private int int1;
+ @Contended("diffGroup2") private int int2;
+ }
+
+ // fields are padded in disjoint groups
+ public static class Test6 {
+ @Contended private int int1;
+ @Contended("diffGroup2") private int int2;
+ }
+
+ // fields are padded in the singular group
+ @Contended
+ public static class Test7 {
+ private int int1;
+ private int int2;
+ }
+
+ // all fields are padded as the group, and one field is padded specifically
+ @Contended
+ public static class Test8 {
+ @Contended private int int1;
+ private int int2;
+ }
+
+ // all fields are padded as the group, and one field is padded specifically
+ @Contended
+ public static class Test9 {
+ @Contended("group") private int int1;
+ private int int2;
+ }
+
+}
+