[10] RFR: 8185164: GetOwnedMonitorInfo() returns incorrect owned monitor
Daniel D. Daugherty
daniel.daugherty at oracle.com
Sun Aug 6 02:33:10 UTC 2017
Hi Yasumasa and Serguei,
I've made some tweaks to the test and attached an updated patch:
GetOwnedMonitorInfoTest.java changes:
- deleted thread 't2'
- made changes to make monitor contention not racy:
- added 'hasEventPosted()' native function
- changed Main to grab the GetOwnedMonitorInfoTest.class monitor
before launching 't1'
- added loop to check hasEventPosted() function while holding
the GetOwnedMonitorInfoTest.class monitor
- moved the delay to this new loop
libGetOwnedMonitorInfoTest.c changes:
- added event_has_posted flag to know when MonitorContendedEnter
event has been posted
- added missing error checks to JVM/TI functions
- print an error message when MonitorContendedEnter or
MonitorContendedEntered gets an incorrect monitor count
- print error and warnings to 'stderr'
- add Java_GetOwnedMonitorInfoTest_hasEventPosted function
I've tested the latest version of test in a repo without the fix
and it fails (as expected). Here's some sample output:
----------System.out:(7/231)----------
Agent_OnLoad started
Agent_OnLoad finished
Main starting worker thread.
Main waiting for event.
Thread in sync section: Thread-1
MonitorContendedEnter: Thread-1 owns 1 monitor(s)
MonitorContendedEntered: Thread-1 owns 1 monitor(s)
----------System.err:(14/931)----------
MonitorContendedEnter: FAIL: monitorCount should be zero.
java.lang.RuntimeException: FAILED status returned from the agent
at GetOwnedMonitorInfoTest.main(GetOwnedMonitorInfoTest.java:81)
at
java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke0(Native
Method)
at
java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
at
java.base/jdk.internal.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at java.base/java.lang.reflect.Method.invoke(Method.java:564)
at
com.sun.javatest.regtest.agent.MainWrapper$MainThread.run(MainWrapper.java:115)
at java.base/java.lang.Thread.run(Thread.java:844)
JavaTest Message: Test threw exception: java.lang.RuntimeException:
FAILED status returned from the agent
JavaTest Message: shutting down test
Dan
On 8/5/17 12:37 PM, serguei.spitsyn at oracle.com wrote:
> Hi Yasumasa,
>
> I use the following script to run the test on linux:
>
> % cat run.sh
> #!/bin/sh
> REPO=<my_repo>
> IMAGES=${REPO}/build/linux-x86_64-normal-server-release/images
> export JAVA_HOME=${IMAGES}/jdk
> export LD_LIBRARY_PATH=${IMAGES}/test/hotspot/jtreg/native
>
> jtreg -J-Dtest.java.opts='-server' \
> -jdk ${JAVA_HOME} \
> -nativepath:${LD_LIBRARY_PATH} \
> $REPO/hotspot/test/serviceability/jvmti/GetOwnedMonitorInfo
>
>
> Thanks,
> Serguei
>
>
> On 8/5/17 06:31, Yasumasa Suenaga wrote:
>> Hi Serguei,
>>
>> I uploaded new webrev:
>> http://cr.openjdk.java.net/~ysuenaga/JDK-8185164/webrev.01/
>>
>> I tried to run serviceability/jvmti/GetOwnedMonitorInfo but it is
>> failed because jtreg needs -nativepath option.
>> But I didn't know what path should I set to -nativepath.
>>
>>
>> Thanks,
>>
>> Yasumasa
>>
>>
>> On 2017/08/05 20:20, serguei.spitsyn at oracle.com wrote:
>>> Hi Yasumasa,
>>>
>>> Please, merge the converted testcase.
>>> It still might need more tweaks though.
>>>
>>> Thanks,
>>> Serguei
>>>
>>>
>>> On 8/5/17 03:18, Yasumasa Suenaga wrote:
>>>> Hi Serguei,
>>>>
>>>> Thank you so much!
>>>> Should I merge your testcase? Or can you push this change?
>>>>
>>>> I agree to your change as a reviewer.
>>>>
>>>>
>>>> Yasumasa
>>>>
>>>>
>>>> On 2017/08/05 11:34, serguei.spitsyn at oracle.com wrote:
>>>>> The updated patch attached.
>>>>> Now the test is passed with the suggested fix and failed without it.
>>>>>
>>>>> Thanks,
>>>>> Serguei
>>>>>
>>>>>
>>>>> On 8/4/17 15:45, serguei.spitsyn at oracle.com wrote:
>>>>>> On 8/4/17 14:26, Daniel D. Daugherty wrote:
>>>>>>> On 8/4/17 3:17 PM, serguei.spitsyn at oracle.com wrote:
>>>>>>>> The patch is attached.
>>>>>>>> It may need some tweaks though.
>>>>>>>> I was not able to make it fail yet.
>>>>>>>
>>>>>>> I don't think the original test had "failure" detection.
>>>>>>> You were just supposed to notice that a pending monitor
>>>>>>> was listed under the wrong list.
>>>>>> Nothing is listed.
>>>>>> Strange thing is I do not see the monitor events fired.
>>>>>> I'm using 10 for testing.
>>>>>>
>>>>>> Thanks,
>>>>>> Serguei
>>>>>>
>>>>>>>
>>>>>>> Dan
>>>>>>>
>>>>>>>
>>>>>>>>
>>>>>>>>
>>>>>>>> On 8/4/17 12:45, Daniel D. Daugherty wrote:
>>>>>>>>> Thanks Serguei!
>>>>>>>>>
>>>>>>>>> I happen to be doing a test run this weekend that includes
>>>>>>>>> most of the
>>>>>>>>> JPDA stack of tests so I'll include the following in my
>>>>>>>>> experiment:
>>>>>>>>>
>>>>>>>>> $ hg log -v -r tip
>>>>>>>>> changeset: 12872:bb66cd7c61b1
>>>>>>>>> tag: 8185164.patch
>>>>>>>>> tag: qtip
>>>>>>>>> tag: tip
>>>>>>>>> user: dcubed
>>>>>>>>> date: Fri Aug 04 13:41:29 2017 -0600
>>>>>>>>> files: src/share/vm/runtime/objectMonitor.cpp
>>>>>>>>> description:
>>>>>>>>> imported patch 8185164.patch
>>>>>>>>>
>>>>>>>>>
>>>>>>>>> That will get the product code changes a complete round of
>>>>>>>>> testing
>>>>>>>>> on Solaris X64 at least... :-)
>>>>>>>>
>>>>>>>> Great!
>>>>>>>>
>>>>>>>> Thanks,
>>>>>>>> Serguei
>>>>>>>>>
>>>>>>>>> Dan
>>>>>>>>>
>>>>>>>>>
>>>>>>>>> On 8/4/17 1:31 PM, serguei.spitsyn at oracle.com wrote:
>>>>>>>>>> Dan,
>>>>>>>>>>
>>>>>>>>>> Thank you for letting me know about this discussion.
>>>>>>>>>> I'll try to convert the attached test case to the JTreg format.
>>>>>>>>>>
>>>>>>>>>> Thanks,
>>>>>>>>>> Serguei
>>>>>>>>>>
>>>>>>>>>>
>>>>>>>>>> On 8/4/17 11:16, Daniel D. Daugherty wrote:
>>>>>>>>>>> Adding Serguei to this thread directly since he's back from
>>>>>>>>>>> vacation!
>>>>>>>>>>>
>>>>>>>>>>>
>>>>>>>>>>> On 7/31/17 10:14 PM, David Holmes wrote:
>>>>>>>>>>>> Hi Dan,
>>>>>>>>>>>>
>>>>>>>>>>>> On 26/07/2017 11:52 PM, Daniel D. Daugherty wrote:
>>>>>>>>>>>>> On 7/26/17 12:11 AM, David Holmes wrote:
>>>>>>>>>>>>>> On 26/07/2017 10:27 AM, Yasumasa Suenaga wrote:
>>>>>>>>>>>>>>> Hi Dan,
>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>>> I've added some analysis to the bug report
>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>> Thanks!
>>>>>>>>>>>>>>> I tried to fix this issue in
>>>>>>>>>>>>>>> JvmtiEnvBase::get_owned_monitors() at first.
>>>>>>>>>>>>>>> But it is difficult because we cannot know pending
>>>>>>>>>>>>>>> monitor if thread state is MONITOR_CONTENDED_ENTER when
>>>>>>>>>>>>>>> get_owned_monitor() is called.
>>>>>>>>>>>>>>
>>>>>>>>>>>>>> I need to look closer at this when I get back from
>>>>>>>>>>>>>> vacation next week.
>>>>>>>>>>>>>
>>>>>>>>>>>>> Seems like you're back already. :-)
>>>>>>>>>>>>>
>>>>>>>>>>>>>
>>>>>>>>>>>>>> A pending monitor should not be reported as owned (unless
>>>>>>>>>>>>>> the spec says otherwise) and it seems odd to me to fix
>>>>>>>>>>>>>> the current problem by marking the monitor as pending
>>>>>>>>>>>>>> earlier.
>>>>>>>>>>>>>
>>>>>>>>>>>>> It's the updating of the _current_pending_monitor field that
>>>>>>>>>>>>> allows JvmtiEnvBase::get_locked_objects_in_frame() to
>>>>>>>>>>>>> recognize
>>>>>>>>>>>>> that the monitor observed in the frame is only pending and
>>>>>>>>>>>>> is not owned.
>>>>>>>>>>>>>
>>>>>>>>>>>>> I put a fairly detailed note in the bug yesterday, but you
>>>>>>>>>>>>> should look at that when you're officially back!
>>>>>>>>>>>>
>>>>>>>>>>>> Thanks for clarifying things. I also added a comment to the
>>>>>>>>>>>> bug report.
>>>>>>>>>>>>
>>>>>>>>>>>> I think the fix is sound and prevents anyone from observing
>>>>>>>>>>>> the case where the monitor will be seen in the stack-frame,
>>>>>>>>>>>> but has not yet been set as the "pending monitor". As far
>>>>>>>>>>>> as I can tell it is only this case (GetOwnedMonitorInfo
>>>>>>>>>>>> from the contended-monitor event callback in the current
>>>>>>>>>>>> thread) that will be able to observe the change.
>>>>>>>>>>>
>>>>>>>>>>> One scenario that I worry about here is that a
>>>>>>>>>>> GetCurrentContendedMonitor()
>>>>>>>>>>> call on a target thread will now be able to return a
>>>>>>>>>>> non-NULL value for the
>>>>>>>>>>> object, when GetThreadState() will be able to return
>>>>>>>>>>> something other than
>>>>>>>>>>> blocked (on monitor enter) for the thread.
>>>>>>>>>>>
>>>>>>>>>>> I don't see anything in the JVM/TI spec that says such a
>>>>>>>>>>> scenario is
>>>>>>>>>>> wrong; I'm only worried about whether we have any tests that
>>>>>>>>>>> would catch
>>>>>>>>>>> this slight change in behavior. In any case, one of these
>>>>>>>>>>> operations has
>>>>>>>>>>> to "happen first":
>>>>>>>>>>>
>>>>>>>>>>> - thread is marked as blocked
>>>>>>>>>>> - monitor is flagged as contended
>>>>>>>>>>>
>>>>>>>>>>> Currently, they happen in the above order and the fix
>>>>>>>>>>> proposes to
>>>>>>>>>>> change the order and I see no reason not to do it.
>>>>>>>>>>>
>>>>>>>>>>> I would like the test attached to the bug to be converted
>>>>>>>>>>> into a native
>>>>>>>>>>> JTREG test that lives in hotspot/test/serviceability/jvmti.
>>>>>>>>>>> See the
>>>>>>>>>>> following test as a possible example:
>>>>>>>>>>>
>>>>>>>>>>> hotspot/test/serviceability/jvmti/GetNamedModule
>>>>>>>>>>>
>>>>>>>>>>> for how to do this... I haven't done one of these new native
>>>>>>>>>>> JTREG
>>>>>>>>>>> tests myself, but I believe Serguei has...
>>>>>>>>>>>
>>>>>>>>>>> Dan
>>>>>>>>>>>
>>>>>>>>>>>
>>>>>>>>>>>>
>>>>>>>>>>>> Thanks,
>>>>>>>>>>>> David
>>>>>>>>>>>>
>>>>>>>>>>>>> Dan
>>>>>>>>>>>>>
>>>>>>>>>>>>>
>>>>>>>>>>>>>>
>>>>>>>>>>>>>> Thanks,
>>>>>>>>>>>>>> David
>>>>>>>>>>>>>>
>>>>>>>>>>>>>>>> Did you run the jdk repo's com/sun/jdi tests with your
>>>>>>>>>>>>>>>> fix?
>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>> I have not done yet.
>>>>>>>>>>>>>>> I have a trip until 28 July JST. So I will run it after
>>>>>>>>>>>>>>> that.
>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>> Yasumasa
>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>> On 2017/07/26 7:05, Daniel D. Daugherty wrote:
>>>>>>>>>>>>>>>> On 7/24/17 8:40 PM, Yasumasa Suenaga wrote:
>>>>>>>>>>>>>>>>> Hi all,
>>>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>>>> I tried to get owned monitors in MonitorContendedEnter
>>>>>>>>>>>>>>>>> JVMTI event handler.
>>>>>>>>>>>>>>>>> However GetOwnedMonitorInfo JVMTI function returns a
>>>>>>>>>>>>>>>>> monitor which is
>>>>>>>>>>>>>>>>> not yet owned.
>>>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>>>> I attached reproducer to JBS. Please read README.md.
>>>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>>>> I think GetOwnedMonitorInfo() should not return a
>>>>>>>>>>>>>>>>> pending monitor.
>>>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>>>> I uploaded webrev. Could you review?
>>>>>>>>>>>>>>>>> http://cr.openjdk.java.net/~ysuenaga/JDK-8185164/webrev.00/
>>>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>>>> I hope this fix is applied to 8u or later release.
>>>>>>>>>>>>>>>>> I cannot access JPRT. So I need a sponsor.
>>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>>> Thanks for the bug report. It's nice to have a test
>>>>>>>>>>>>>>>> case and a proposed
>>>>>>>>>>>>>>>> fix all in the bug report! I've added some analysis to
>>>>>>>>>>>>>>>> the bug report
>>>>>>>>>>>>>>>> and we'll need to run this fix through Oracle's JPDA
>>>>>>>>>>>>>>>> test stack which
>>>>>>>>>>>>>>>> is not (yet) open.
>>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>>> Did you run the jdk repo's com/sun/jdi tests with your
>>>>>>>>>>>>>>>> fix?
>>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>>> Dan
>>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>>>> Thanks,
>>>>>>>>>>>>>>>>>
>>>>>>>>>>>>>>>>> Yasumasa
>>>>>>>>>>>>>>>>
>>>>>>>>>>>>>
>>>>>>>>>>>
>>>>>>>>>>
>>>>>>>>>
>>>>>>>>
>>>>>>>
>>>>>>
>>>>>
>>>
>
-------------- next part --------------
# HG changeset patch
# User dcubed
# Date 1501985618 21600
# Sat Aug 05 20:13:38 2017 -0600
# Node ID a30e98329adab636e82d169954fad68b7299ac0b
# Parent 2f9492e874f5a14bbdf57c84d2767f413c74c86f
imported patch 8185164.1.patch
diff -r 2f9492e874f5 -r a30e98329ada make/test/JtregNative.gmk
--- a/make/test/JtregNative.gmk Sat Aug 05 20:13:05 2017 -0600
+++ b/make/test/JtregNative.gmk Sat Aug 05 20:13:38 2017 -0600
@@ -55,6 +55,7 @@
$(HOTSPOT_TOPDIR)/test/runtime/BoolReturn \
$(HOTSPOT_TOPDIR)/test/compiler/floatingpoint/ \
$(HOTSPOT_TOPDIR)/test/compiler/calls \
+ $(HOTSPOT_TOPDIR)/test/serviceability/jvmti/GetOwnedMonitorInfo \
$(HOTSPOT_TOPDIR)/test/serviceability/jvmti/GetNamedModule \
$(HOTSPOT_TOPDIR)/test/serviceability/jvmti/IsModifiableModule \
$(HOTSPOT_TOPDIR)/test/serviceability/jvmti/AddModuleReads \
@@ -85,6 +86,7 @@
ifeq ($(TOOLCHAIN_TYPE), solstudio)
BUILD_HOTSPOT_JTREG_LIBRARIES_LIBS_liboverflow := -lc
BUILD_HOTSPOT_JTREG_LIBRARIES_LIBS_libSimpleClassFileLoadHook := -lc
+ BUILD_HOTSPOT_JTREG_LIBRARIES_LIBS_libGetOwnedMonitorInfoTest := -lc
BUILD_HOTSPOT_JTREG_LIBRARIES_LIBS_libGetNamedModuleTest := -lc
BUILD_HOTSPOT_JTREG_LIBRARIES_LIBS_libIsModifiableModuleTest := -lc
BUILD_HOTSPOT_JTREG_LIBRARIES_LDFLAGS_libAddModuleReadsTest := -lc
diff -r 2f9492e874f5 -r a30e98329ada src/share/vm/runtime/objectMonitor.cpp
--- a/src/share/vm/runtime/objectMonitor.cpp Sat Aug 05 20:13:05 2017 -0600
+++ b/src/share/vm/runtime/objectMonitor.cpp Sat Aug 05 20:13:38 2017 -0600
@@ -307,6 +307,8 @@
{ // Change java thread status to indicate blocked on monitor enter.
JavaThreadBlockedOnMonitorEnterState jtbmes(jt, this);
+ Self->set_current_pending_monitor(this);
+
DTRACE_MONITOR_PROBE(contended__enter, this, object(), jt);
if (JvmtiExport::should_post_monitor_contended_enter()) {
JvmtiExport::post_monitor_contended_enter(jt, this);
@@ -321,8 +323,6 @@
OSThreadContendState osts(Self->osthread());
ThreadBlockInVM tbivm(jt);
- Self->set_current_pending_monitor(this);
-
// TODO-FIXME: change the following for(;;) loop to straight-line code.
for (;;) {
jt->set_suspend_equivalent();
diff -r 2f9492e874f5 -r a30e98329ada test/serviceability/jvmti/GetOwnedMonitorInfo/GetOwnedMonitorInfoTest.java
--- /dev/null Thu Jan 01 00:00:00 1970 +0000
+++ b/test/serviceability/jvmti/GetOwnedMonitorInfo/GetOwnedMonitorInfoTest.java Sat Aug 05 20:13:38 2017 -0600
@@ -0,0 +1,84 @@
+/*
+ * 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
+ * @summary Verifies the JVMTI GetOwnedMonitorInfo API
+ * @modules jdk.jdi
+ * @compile GetOwnedMonitorInfoTest.java
+ * @run main/othervm/native -agentlib:GetOwnedMonitorInfoTest GetOwnedMonitorInfoTest
+ */
+
+import java.io.PrintStream;
+
+public class GetOwnedMonitorInfoTest implements Runnable {
+
+ static {
+ try {
+ System.loadLibrary("GetOwnedMonitorInfoTest");
+ } catch (UnsatisfiedLinkError ule) {
+ System.err.println("Could not load GetOwnedMonitorInfoTest library");
+ System.err.println("java.library.path: "
+ + System.getProperty("java.library.path"));
+ throw ule;
+ }
+ }
+
+ native static int check();
+ native static boolean hasEventPosted();
+
+ public void run() {
+ String name = Thread.currentThread().getName();
+ try {
+ synchronized (GetOwnedMonitorInfoTest.class) {
+ System.out.println("Thread in sync section: " + name);
+ }
+ } catch (Exception e) {
+ e.printStackTrace();
+ }
+ }
+
+ public static void main(String[] args) throws Exception {
+ Thread t1 = new Thread(new GetOwnedMonitorInfoTest());
+
+ // Make sure t1 contends on the monitor.
+ synchronized (GetOwnedMonitorInfoTest.class) {
+ System.out.println("Main starting worker thread.");
+ t1.start();
+
+ // Wait for the MonitorContendedEnter event
+ while (!hasEventPosted()) {
+ System.out.println("Main waiting for event.");
+ Thread.sleep(100);
+ }
+ }
+
+ t1.join();
+
+ int status = check();
+ if (status != 0) {
+ throw new RuntimeException("FAILED status returned from the agent");
+ }
+ }
+}
diff -r 2f9492e874f5 -r a30e98329ada test/serviceability/jvmti/GetOwnedMonitorInfo/libGetOwnedMonitorInfoTest.c
--- /dev/null Thu Jan 01 00:00:00 1970 +0000
+++ b/test/serviceability/jvmti/GetOwnedMonitorInfo/libGetOwnedMonitorInfoTest.c Sat Aug 05 20:13:38 2017 -0600
@@ -0,0 +1,217 @@
+/*
+ * 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.
+ */
+
+#include <stdio.h>
+#include <string.h>
+#include "jvmti.h"
+#include "jni.h"
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+#ifndef JNI_ENV_ARG
+
+#ifdef __cplusplus
+#define JNI_ENV_ARG(x, y) y
+#define JNI_ENV_PTR(x) x
+#else
+#define JNI_ENV_ARG(x,y) x, y
+#define JNI_ENV_PTR(x) (*x)
+#endif
+
+#endif
+
+#define TranslateError(err) "JVMTI error"
+
+#define PASSED 0
+#define FAILED 2
+
+static volatile jboolean event_has_posted = JNI_FALSE;
+static jint status = PASSED;
+
+static jint Agent_Initialize(JavaVM *jvm, char *options, void *reserved);
+
+JNIEXPORT void JNICALL
+MonitorContendedEnter(jvmtiEnv *jvmti, JNIEnv *env, jthread thread, jobject monitor) {
+ jvmtiError err;
+ jvmtiThreadInfo threadInfo;
+ jint monitorCount;
+ jobject *ownedMonitors;
+
+ event_has_posted = JNI_TRUE;
+
+ err = (*jvmti)->GetThreadInfo(jvmti, thread, &threadInfo);
+ if (err != JVMTI_ERROR_NONE) {
+ fprintf(stderr, "MonitorContendedEnter: error in JVMTI GetThreadInfo: %d\n", err);
+ status = FAILED;
+ return;
+ }
+ err = (*jvmti)->GetOwnedMonitorInfo(jvmti, thread, &monitorCount, &ownedMonitors);
+ if (err != JVMTI_ERROR_NONE) {
+ fprintf(stderr, "MonitorContendedEnter: error in JVMTI GetOwnedMonitorInfo: %d\n", err);
+ status = FAILED;
+ return;
+ }
+
+ printf("MonitorContendedEnter: %s owns %d monitor(s)\n",
+ threadInfo.name, monitorCount);
+
+ (*jvmti)->Deallocate(jvmti, (unsigned char *)ownedMonitors);
+ (*jvmti)->Deallocate(jvmti, (unsigned char *)threadInfo.name);
+
+ if (monitorCount != 0) {
+ fprintf(stderr, "MonitorContendedEnter: FAIL: monitorCount should be zero.\n");
+ status = FAILED;
+ }
+}
+
+JNIEXPORT void JNICALL
+MonitorContendedEntered(jvmtiEnv *jvmti, JNIEnv *env, jthread thread, jobject monitor) {
+ jvmtiError err;
+ jvmtiThreadInfo threadInfo;
+ jint monitorCount;
+ jobject *ownedMonitors;
+
+ err = (*jvmti)->GetThreadInfo(jvmti, thread, &threadInfo);
+ if (err != JVMTI_ERROR_NONE) {
+ fprintf(stderr, "MonitorContendedEntered: error in JVMTI GetThreadInfo: %d\n", err);
+ status = FAILED;
+ return;
+ }
+ err = (*jvmti)->GetOwnedMonitorInfo(jvmti, thread, &monitorCount, &ownedMonitors);
+ if (err != JVMTI_ERROR_NONE) {
+ fprintf(stderr, "MonitorContendedEntered: error in JVMTI GetOwnedMonitorInfo: %d\n", err);
+ status = FAILED;
+ return;
+ }
+
+ printf("MonitorContendedEntered: %s owns %d monitor(s)\n",
+ threadInfo.name, monitorCount);
+
+ (*jvmti)->Deallocate(jvmti, (unsigned char *)ownedMonitors);
+ (*jvmti)->Deallocate(jvmti, (unsigned char *)threadInfo.name);
+
+ if (monitorCount != 1) {
+ fprintf(stderr, "MonitorContendedEnter: FAIL: monitorCount should be one.\n");
+ status = FAILED;
+ }
+}
+
+JNIEXPORT jint JNICALL
+Agent_OnLoad(JavaVM *jvm, char *options, void *reserved) {
+ return Agent_Initialize(jvm, options, reserved);
+}
+
+JNIEXPORT jint JNICALL
+Agent_OnAttach(JavaVM *jvm, char *options, void *reserved) {
+ return Agent_Initialize(jvm, options, reserved);
+}
+
+JNIEXPORT jint JNICALL
+JNI_OnLoad(JavaVM *jvm, void *reserved) {
+ return JNI_VERSION_1_8;
+}
+
+static
+jint Agent_Initialize(JavaVM *jvm, char *options, void *reserved) {
+ jint res;
+ jvmtiError err;
+ jvmtiEnv *jvmti;
+ jvmtiCapabilities caps;
+ jvmtiEventCallbacks callbacks;
+
+ printf("Agent_OnLoad started\n");
+
+ res = JNI_ENV_PTR(jvm)->GetEnv(JNI_ENV_ARG(jvm, (void **) &jvmti),
+ JVMTI_VERSION_1);
+ if (res != JNI_OK || jvmti == NULL) {
+ fprintf(stderr, "Error: wrong result of a valid call to GetEnv!\n");
+ return JNI_ERR;
+ }
+
+ err = (*jvmti)->GetPotentialCapabilities(jvmti, &caps);
+ if (err != JVMTI_ERROR_NONE) {
+ fprintf(stderr, "Agent_OnLoad: error in JVMTI GetPotentialCapabilities: %d\n", err);
+ return JNI_ERR;
+ }
+
+ err = (*jvmti)->AddCapabilities(jvmti, &caps);
+ if (err != JVMTI_ERROR_NONE) {
+ fprintf(stderr, "Agent_OnLoad: error in JVMTI AddCapabilities: %d\n", err);
+ return JNI_ERR;
+ }
+
+ err = (*jvmti)->GetCapabilities(jvmti, &caps);
+ if (err != JVMTI_ERROR_NONE) {
+ fprintf(stderr, "Agent_OnLoad: error in JVMTI GetCapabilities: %d\n", err);
+ return JNI_ERR;
+ }
+
+ if (!caps.can_generate_monitor_events) {
+ fprintf(stderr, "Warning: Monitor events are not implemented\n");
+ return JNI_ERR;
+ }
+ if (!caps.can_get_owned_monitor_info) {
+ fprintf(stderr, "Warning: GetOwnedMonitorInfo is not implemented\n");
+ return JNI_ERR;
+ }
+
+ callbacks.MonitorContendedEnter = &MonitorContendedEnter;
+ callbacks.MonitorContendedEntered = &MonitorContendedEntered;
+
+ err = (*jvmti)->SetEventCallbacks(jvmti, &callbacks, sizeof(jvmtiEventCallbacks));
+ if (err != JVMTI_ERROR_NONE) {
+ fprintf(stderr, "Agent_OnLoad: error in JVMTI SetEventCallbacks: %d\n", err);
+ return JNI_ERR;
+ }
+
+ err = (*jvmti)->SetEventNotificationMode(jvmti, JVMTI_ENABLE,
+ JVMTI_EVENT_MONITOR_CONTENDED_ENTER, NULL);
+ if (err != JVMTI_ERROR_NONE) {
+ fprintf(stderr, "Agent_OnLoad: error in JVMTI SetEventNotificationMode #1: %d\n", err);
+ return JNI_ERR;
+ }
+ err = (*jvmti)->SetEventNotificationMode(jvmti, JVMTI_ENABLE,
+ JVMTI_EVENT_MONITOR_CONTENDED_ENTERED, NULL);
+ if (err != JVMTI_ERROR_NONE) {
+ fprintf(stderr, "Agent_OnLoad: error in JVMTI SetEventNotificationMode #2: %d\n", err);
+ return JNI_ERR;
+ }
+ printf("Agent_OnLoad finished\n");
+ return JNI_OK;
+}
+
+JNIEXPORT jint JNICALL
+Java_GetOwnedMonitorInfoTest_check(JNIEnv *env, jclass cls) {
+ return status;
+}
+
+JNIEXPORT jboolean JNICALL
+Java_GetOwnedMonitorInfoTest_hasEventPosted(JNIEnv *env, jclass cls) {
+ return event_has_posted;
+}
+
+#ifdef __cplusplus
+}
+#endif
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