1/*
2 * Copyright (c) 2015, 2018, Oracle and/or its affiliates. All rights reserved.
3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
4 *
5 * This code is free software; you can redistribute it and/or modify it
6 * under the terms of the GNU General Public License version 2 only, as
7 * published by the Free Software Foundation.
8 *
9 * This code is distributed in the hope that it will be useful, but WITHOUT
10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
12 * version 2 for more details (a copy is included in the LICENSE file that
13 * accompanied this code).
14 *
15 * You should have received a copy of the GNU General Public License version
16 * 2 along with this work; if not, write to the Free Software Foundation,
17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
18 *
19 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
20 * or visit www.oracle.com if you need additional information or have any
21 * questions.
22 *
23 */
24
25#include "precompiled.hpp"
26#include "runtime/arguments.hpp"
27#include "runtime/flags/jvmFlag.hpp"
28#include "runtime/flags/jvmFlagConstraintsRuntime.hpp"
29#include "runtime/globals.hpp"
30#include "runtime/safepointMechanism.hpp"
31#include "runtime/task.hpp"
32
33JVMFlag::Error ObjectAlignmentInBytesConstraintFunc(intx value, bool verbose) {
34 if (!is_power_of_2(value)) {
35 JVMFlag::printError(verbose,
36 "ObjectAlignmentInBytes (" INTX_FORMAT ") must be "
37 "power of 2\n",
38 value);
39 return JVMFlag::VIOLATES_CONSTRAINT;
40 }
41 // In case page size is very small.
42 if (value >= (intx)os::vm_page_size()) {
43 JVMFlag::printError(verbose,
44 "ObjectAlignmentInBytes (" INTX_FORMAT ") must be "
45 "less than page size (%d)\n",
46 value, os::vm_page_size());
47 return JVMFlag::VIOLATES_CONSTRAINT;
48 }
49 return JVMFlag::SUCCESS;
50}
51
52// Need to enforce the padding not to break the existing field alignments.
53// It is sufficient to check against the largest type size.
54JVMFlag::Error ContendedPaddingWidthConstraintFunc(intx value, bool verbose) {
55 if ((value % BytesPerLong) != 0) {
56 JVMFlag::printError(verbose,
57 "ContendedPaddingWidth (" INTX_FORMAT ") must be "
58 "a multiple of %d\n",
59 value, BytesPerLong);
60 return JVMFlag::VIOLATES_CONSTRAINT;
61 } else {
62 return JVMFlag::SUCCESS;
63 }
64}
65
66JVMFlag::Error BiasedLockingBulkRebiasThresholdFunc(intx value, bool verbose) {
67 if (value > BiasedLockingBulkRevokeThreshold) {
68 JVMFlag::printError(verbose,
69 "BiasedLockingBulkRebiasThreshold (" INTX_FORMAT ") must be "
70 "less than or equal to BiasedLockingBulkRevokeThreshold (" INTX_FORMAT ")\n",
71 value, BiasedLockingBulkRevokeThreshold);
72 return JVMFlag::VIOLATES_CONSTRAINT;
73 } else {
74 return JVMFlag::SUCCESS;
75 }
76}
77
78JVMFlag::Error BiasedLockingStartupDelayFunc(intx value, bool verbose) {
79 if ((value % PeriodicTask::interval_gran) != 0) {
80 JVMFlag::printError(verbose,
81 "BiasedLockingStartupDelay (" INTX_FORMAT ") must be "
82 "evenly divisible by PeriodicTask::interval_gran (%d)\n",
83 value, PeriodicTask::interval_gran);
84 return JVMFlag::VIOLATES_CONSTRAINT;
85 } else {
86 return JVMFlag::SUCCESS;
87 }
88}
89
90JVMFlag::Error BiasedLockingBulkRevokeThresholdFunc(intx value, bool verbose) {
91 if (value < BiasedLockingBulkRebiasThreshold) {
92 JVMFlag::printError(verbose,
93 "BiasedLockingBulkRevokeThreshold (" INTX_FORMAT ") must be "
94 "greater than or equal to BiasedLockingBulkRebiasThreshold (" INTX_FORMAT ")\n",
95 value, BiasedLockingBulkRebiasThreshold);
96 return JVMFlag::VIOLATES_CONSTRAINT;
97 } else if ((double)value/(double)BiasedLockingDecayTime > 0.1) {
98 JVMFlag::printError(verbose,
99 "The ratio of BiasedLockingBulkRevokeThreshold (" INTX_FORMAT ")"
100 " to BiasedLockingDecayTime (" INTX_FORMAT ") must be "
101 "less than or equal to 0.1\n",
102 value, BiasedLockingBulkRebiasThreshold);
103 return JVMFlag::VIOLATES_CONSTRAINT;
104 } else {
105 return JVMFlag::SUCCESS;
106 }
107}
108
109JVMFlag::Error BiasedLockingDecayTimeFunc(intx value, bool verbose) {
110 if (BiasedLockingBulkRebiasThreshold/(double)value > 0.1) {
111 JVMFlag::printError(verbose,
112 "The ratio of BiasedLockingBulkRebiasThreshold (" INTX_FORMAT ")"
113 " to BiasedLockingDecayTime (" INTX_FORMAT ") must be "
114 "less than or equal to 0.1\n",
115 BiasedLockingBulkRebiasThreshold, value);
116 return JVMFlag::VIOLATES_CONSTRAINT;
117 } else {
118 return JVMFlag::SUCCESS;
119 }
120}
121
122JVMFlag::Error PerfDataSamplingIntervalFunc(intx value, bool verbose) {
123 if ((value % PeriodicTask::interval_gran != 0)) {
124 JVMFlag::printError(verbose,
125 "PerfDataSamplingInterval (" INTX_FORMAT ") must be "
126 "evenly divisible by PeriodicTask::interval_gran (%d)\n",
127 value, PeriodicTask::interval_gran);
128 return JVMFlag::VIOLATES_CONSTRAINT;
129 } else {
130 return JVMFlag::SUCCESS;
131 }
132}
133
134JVMFlag::Error ThreadLocalHandshakesConstraintFunc(bool value, bool verbose) {
135 if (value) {
136 if (!SafepointMechanism::supports_thread_local_poll()) {
137 JVMFlag::printError(verbose, "ThreadLocalHandshakes not yet supported on this platform\n");
138 return JVMFlag::VIOLATES_CONSTRAINT;
139 }
140 }
141 return JVMFlag::SUCCESS;
142}
143