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Zhengyu Gu
committed
Implementation of Safepoint events
1 parent 6f0d40b commit 74510f8

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5 files changed

+146
-7
lines changed

5 files changed

+146
-7
lines changed

‎substratevm/src/com.oracle.svm.core/src/com/oracle/svm/core/jfr/JfrEvent.java‎

Lines changed: 3 additions & 1 deletion
Original file line numberDiff line numberDiff line change
@@ -49,7 +49,9 @@ public enum JfrEvent {
4949
GCPhasePauseLevel1Event("jdk.GCPhasePauseLevel1"),
5050
GCPhasePauseLevel2Event("jdk.GCPhasePauseLevel2"),
5151
GCPhasePauseLevel3Event("jdk.GCPhasePauseLevel3"),
52-
GCPhasePauseLevel4Event("jdk.GCPhasePauseLevel4");
52+
GCPhasePauseLevel4Event("jdk.GCPhasePauseLevel4"),
53+
SafepointBegin("jdk.SafepointBegin"),
54+
SafepointEnd("jdk.SafepointEnd");
5355

5456
private final long id;
5557

‎substratevm/src/com.oracle.svm.core/src/com/oracle/svm/core/jfr/JfrTicks.java‎

Lines changed: 6 additions & 2 deletions
Original file line numberDiff line numberDiff line change
@@ -44,8 +44,12 @@ public static void initialize() {
4444

4545
@Uninterruptible(reason = "Called from uninterruptible code.", mayBeInlined = true)
4646
public static long elapsedTicks() {
47-
assert initialTicks > 0;
48-
return System.nanoTime() - initialTicks;
47+
if (HasJfrSupport.get()) {
48+
assert initialTicks > 0;
49+
return System.nanoTime() - initialTicks;
50+
} else {
51+
return 0;
52+
}
4953
}
5054

5155
public static long getTicksFrequency() {

‎substratevm/src/com.oracle.svm.core/src/com/oracle/svm/core/jfr/events/SafepointBeginEvent.java‎

Lines changed: 63 additions & 0 deletions
Original file line numberDiff line numberDiff line change
@@ -0,0 +1,63 @@
1+
/*
2+
* Copyright (c) 2022, 2022, Oracle and/or its affiliates. All rights reserved.
3+
* Copyright (c) 2022, 2022, Red Hat Inc. All rights reserved.
4+
* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
5+
*
6+
* This code is free software; you can redistribute it and/or modify it
7+
* under the terms of the GNU General Public License version 2 only, as
8+
* published by the Free Software Foundation. Oracle designates this
9+
* particular file as subject to the "Classpath" exception as provided
10+
* by Oracle in the LICENSE file that accompanied this code.
11+
*
12+
* This code is distributed in the hope that it will be useful, but WITHOUT
13+
* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
14+
* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
15+
* version 2 for more details (a copy is included in the LICENSE file that
16+
* accompanied this code).
17+
*
18+
* You should have received a copy of the GNU General Public License version
19+
* 2 along with this work; if not, write to the Free Software Foundation,
20+
* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
21+
*
22+
* Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
23+
* or visit www.oracle.com if you need additional information or have any
24+
* questions.
25+
*/
26+
27+
package com.oracle.svm.core.jfr.events;
28+
29+
import com.oracle.svm.core.annotate.Uninterruptible;
30+
import com.oracle.svm.core.jfr.JfrEvent;
31+
import com.oracle.svm.core.jfr.HasJfrSupport;
32+
import com.oracle.svm.core.jfr.JfrNativeEventWriter;
33+
import com.oracle.svm.core.jfr.JfrNativeEventWriterData;
34+
import com.oracle.svm.core.jfr.JfrNativeEventWriterDataAccess;
35+
import com.oracle.svm.core.jfr.JfrTicks;
36+
import com.oracle.svm.core.jfr.SubstrateJVM;
37+
38+
import org.graalvm.nativeimage.StackValue;
39+
import org.graalvm.word.UnsignedWord;
40+
41+
public class SafepointBeginEvent {
42+
@Uninterruptible(reason = "Accesses a JFR buffer.")
43+
public static void emit(UnsignedWord safepointId, int numOfThreads, long startTicks) {
44+
if (!HasJfrSupport.get()) {
45+
return;
46+
}
47+
48+
if (SubstrateJVM.isRecording() && SubstrateJVM.get().isEnabled(JfrEvent.SafepointBegin)) {
49+
JfrNativeEventWriterData data = StackValue.get(JfrNativeEventWriterData.class);
50+
JfrNativeEventWriterDataAccess.initializeThreadLocalNativeBuffer(data);
51+
52+
JfrNativeEventWriter.beginEventWrite(data, false);
53+
JfrNativeEventWriter.putLong(data, JfrEvent.SafepointBegin.getId());
54+
JfrNativeEventWriter.putLong(data, startTicks);
55+
JfrNativeEventWriter.putLong(data, JfrTicks.elapsedTicks() - startTicks);
56+
JfrNativeEventWriter.putEventThread(data);
57+
JfrNativeEventWriter.putLong(data, safepointId.rawValue());
58+
JfrNativeEventWriter.putInt(data, numOfThreads);
59+
JfrNativeEventWriter.putInt(data, 0); // jniCriticalThreadCount
60+
JfrNativeEventWriter.endEventWrite(data, false);
61+
}
62+
}
63+
}

‎substratevm/src/com.oracle.svm.core/src/com/oracle/svm/core/jfr/events/SafepointEndEvent.java‎

Lines changed: 61 additions & 0 deletions
Original file line numberDiff line numberDiff line change
@@ -0,0 +1,61 @@
1+
/*
2+
* Copyright (c) 2022, 2022, Oracle and/or its affiliates. All rights reserved.
3+
* Copyright (c) 2022, 2022, Red Hat Inc. All rights reserved.
4+
* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
5+
*
6+
* This code is free software; you can redistribute it and/or modify it
7+
* under the terms of the GNU General Public License version 2 only, as
8+
* published by the Free Software Foundation. Oracle designates this
9+
* particular file as subject to the "Classpath" exception as provided
10+
* by Oracle in the LICENSE file that accompanied this code.
11+
*
12+
* This code is distributed in the hope that it will be useful, but WITHOUT
13+
* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
14+
* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
15+
* version 2 for more details (a copy is included in the LICENSE file that
16+
* accompanied this code).
17+
*
18+
* You should have received a copy of the GNU General Public License version
19+
* 2 along with this work; if not, write to the Free Software Foundation,
20+
* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
21+
*
22+
* Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
23+
* or visit www.oracle.com if you need additional information or have any
24+
* questions.
25+
*/
26+
27+
package com.oracle.svm.core.jfr.events;
28+
29+
import com.oracle.svm.core.annotate.Uninterruptible;
30+
import com.oracle.svm.core.jfr.JfrEvent;
31+
import com.oracle.svm.core.jfr.HasJfrSupport;
32+
import com.oracle.svm.core.jfr.JfrNativeEventWriter;
33+
import com.oracle.svm.core.jfr.JfrNativeEventWriterData;
34+
import com.oracle.svm.core.jfr.JfrNativeEventWriterDataAccess;
35+
import com.oracle.svm.core.jfr.JfrTicks;
36+
import com.oracle.svm.core.jfr.SubstrateJVM;
37+
38+
import org.graalvm.nativeimage.StackValue;
39+
import org.graalvm.word.UnsignedWord;
40+
41+
public class SafepointEndEvent {
42+
@Uninterruptible(reason = "Accesses a JFR buffer.")
43+
public static void emit(UnsignedWord safepointId, long startTick) {
44+
if (!HasJfrSupport.get()) {
45+
return;
46+
}
47+
48+
if (SubstrateJVM.isRecording() && SubstrateJVM.get().isEnabled(JfrEvent.SafepointEnd)) {
49+
JfrNativeEventWriterData data = StackValue.get(JfrNativeEventWriterData.class);
50+
JfrNativeEventWriterDataAccess.initializeThreadLocalNativeBuffer(data);
51+
52+
JfrNativeEventWriter.beginEventWrite(data, false);
53+
JfrNativeEventWriter.putLong(data, JfrEvent.SafepointEnd.getId());
54+
JfrNativeEventWriter.putLong(data, startTick);
55+
JfrNativeEventWriter.putLong(data, JfrTicks.elapsedTicks() - startTick);
56+
JfrNativeEventWriter.putEventThread(data);
57+
JfrNativeEventWriter.putLong(data, safepointId.rawValue());
58+
JfrNativeEventWriter.endEventWrite(data, false);
59+
}
60+
}
61+
}

‎substratevm/src/com.oracle.svm.core/src/com/oracle/svm/core/thread/Safepoint.java‎

Lines changed: 13 additions & 4 deletions
Original file line numberDiff line numberDiff line change
@@ -1,5 +1,5 @@
11
/*
2-
* Copyright (c) 2015, 2019, Oracle and/or its affiliates. All rights reserved.
2+
* Copyright (c) 2015, 2022, Oracle and/or its affiliates. All rights reserved.
33
* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
44
*
55
* This code is free software; you can redistribute it and/or modify it
@@ -57,6 +57,9 @@
5757
import com.oracle.svm.core.graal.nodes.KillMemoryNode;
5858
import com.oracle.svm.core.heap.Heap;
5959
import com.oracle.svm.core.jdk.UninterruptibleUtils;
60+
import com.oracle.svm.core.jfr.JfrTicks;
61+
import com.oracle.svm.core.jfr.events.SafepointBeginEvent;
62+
import com.oracle.svm.core.jfr.events.SafepointEndEvent;
6063
import com.oracle.svm.core.log.Log;
6164
import com.oracle.svm.core.nodes.CFunctionEpilogueNode;
6265
import com.oracle.svm.core.nodes.CFunctionPrologueNode;
@@ -612,6 +615,7 @@ private Master() {
612615
protected boolean freeze(String reason) {
613616
assert SubstrateOptions.MultiThreaded.getValue() : "Should only freeze for a safepoint when multi-threaded.";
614617
assert VMOperationControl.mayExecuteVmOperations();
618+
long startTicks = JfrTicks.elapsedTicks();
615619

616620
/* the current thread may already own the lock for non-safepoint reasons */
617621
boolean lock = !VMThreads.THREAD_MUTEX.isOwner();
@@ -624,11 +628,12 @@ protected boolean freeze(String reason) {
624628
Statistics.setStartNanos();
625629
ImageSingletons.lookup(Heap.class).prepareForSafepoint();
626630
safepointState = SYNCHRONIZING;
627-
requestSafepoints(reason);
631+
int numOfThreads = requestSafepoints(reason);
628632
waitForSafepoints(reason);
629633
Statistics.setFrozenNanos();
630634
safepointState = AT_SAFEPOINT;
631635
safepointId = safepointId.add(1);
636+
SafepointBeginEvent.emit(getSafepointId(), numOfThreads, startTicks);
632637
return lock;
633638
}
634639

@@ -637,9 +642,10 @@ protected boolean freeze(String reason) {
637642
protected void thaw(String reason, boolean unlock) {
638643
assert SubstrateOptions.MultiThreaded.getValue() : "Should only thaw from a safepoint when multi-threaded.";
639644
assert VMOperationControl.mayExecuteVmOperations();
640-
645+
long startTicks = JfrTicks.elapsedTicks();
641646
safepointState = NOT_AT_SAFEPOINT;
642647
releaseSafepoints(reason);
648+
SafepointEndEvent.emit(getSafepointId(), startTicks);
643649
ImageSingletons.lookup(Heap.class).endSafepoint();
644650
Statistics.setThawedNanos();
645651
requestingThread = WordFactory.nullPointer();
@@ -657,12 +663,14 @@ private static boolean isMyself(IsolateThread thread) {
657663
}
658664

659665
/** Send each of the threads (except myself) a request to come to a safepoint. */
660-
private static void requestSafepoints(String reason) {
666+
private static int requestSafepoints(String reason) {
661667
VMThreads.THREAD_MUTEX.assertIsOwner("Must hold mutex while requesting a safepoint.");
662668
final Log trace = Log.noopLog().string("[Safepoint.Master.requestSafepoints: reason: ").string(reason);
669+
int numOfThreads = 0;
663670

664671
// Walk the threads list and ask each thread (except myself) to come to a safepoint.
665672
for (IsolateThread vmThread = VMThreads.firstThread(); vmThread.isNonNull(); vmThread = VMThreads.nextThread(vmThread)) {
673+
numOfThreads++;
666674
if (isMyself(vmThread)) {
667675
continue;
668676
}
@@ -677,6 +685,7 @@ private static void requestSafepoints(String reason) {
677685
trace.string(" with requests: ").signed(Statistics.getRequested());
678686
}
679687
trace.string("]").newline();
688+
return numOfThreads;
680689
}
681690

682691
/**

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