RFR: 8371194: serviceability/sa/TestJhsdbJstackMixedWithXComp.java failing [v2]

[Yasumasa Suenaga]

On Tue, 18 Nov 2025 04:45:46 GMT, Chris Plummer <cjplummer at openjdk.org> wrote:

>> Yasumasa Suenaga has updated the pull request incrementally with one additional commit since the last revision:
>> 
>>   Update for Linux PPC64 and RISC-V
>
> On macosx I'm seeing the following when running ClhsdbPStack.java:
> ``` Opening core file, please wait...
> hsdb> hsdb> + verbose true
> hsdb> + pstack -v
> Deadlock Detection:
> 
> No deadlocks found.
> 
> Not available for Mac OS X processes
> hsdb> + quit
> 
> The "Not available for Mac OS X processes" message is expected when running on a macosx process, but in this case the test is running the core version of the test, so SA is acting on a core file. The test goes on to fail because there are no threads in the output.
> 
> The message is generated by PStack.java whenever the thread list is null and it is running on OSX. In that case it assumes the reason the thread list is null is because it is running on a macosx process. It's not clear to me why the thread list is null. I don't see any changes that look like they could cause that.
> 
> This happens with both x64 and aarch64, although you need to remove the test from the problem list for macosx-aarch64 to get it to reproduce. macosx-x64 is not problem listed.

@plummercj Can you try this patch on your Mac? You can apply it to this PR branch.


diff --git a/src/jdk.hotspot.agent/share/classes/sun/jvm/hotspot/debugger/bsd/BsdDebuggerLocal.java b/src/jdk.hotspot.agent/share/classes/sun/jvm/hotspot/debugger/bsd/BsdDebuggerLocal.java
index 10f6881d010..f091b22f9d7 100644
--- a/src/jdk.hotspot.agent/share/classes/sun/jvm/hotspot/debugger/bsd/BsdDebuggerLocal.java
+++ b/src/jdk.hotspot.agent/share/classes/sun/jvm/hotspot/debugger/bsd/BsdDebuggerLocal.java
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2002, 2024, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2002, 2025, 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
@@ -25,7 +25,9 @@
 package sun.jvm.hotspot.debugger.bsd;

 import java.util.ArrayList;
+import java.util.Collections;
 import java.util.List;
+import java.util.stream.IntStream;

 import sun.jvm.hotspot.debugger.Address;
 import sun.jvm.hotspot.debugger.DebuggerBase;
@@ -75,10 +77,11 @@ public class BsdDebuggerLocal extends DebuggerBase implements BsdDebugger {
     // CDebugger support
     private BsdCDebugger cdbg;

-    // threadList and loadObjectList are filled by attach0 method
-    private List<ThreadProxy> threadList;
+    // loadObjectList are filled by attach0 method
     private List<LoadObject> loadObjectList;

+    private List<JavaThread> javaThreadList;
+
     // called by native method lookupByAddress0
     private ClosestSymbol createClosestSymbol(String name, long offset) {
        return new ClosestSymbol(name, offset);
@@ -244,7 +247,7 @@ private void findABIVersion() throws DebuggerException {
     /** From the Debugger interface via JVMDebugger */
     public synchronized void attach(int processID) throws DebuggerException {
         checkAttached();
-        threadList = new ArrayList<>();
+        javaThreadList = new ArrayList<>();
         loadObjectList = new ArrayList<>();
         class AttachTask implements WorkerThreadTask {
            int pid;
@@ -264,7 +267,7 @@ public void doit(BsdDebuggerLocal debugger) {
     /** From the Debugger interface via JVMDebugger */
     public synchronized void attach(String execName, String coreName) {
         checkAttached();
-        threadList = new ArrayList<>();
+        javaThreadList = new ArrayList<>();
         loadObjectList = new ArrayList<>();
         attach0(execName, coreName);
         attached = true;
@@ -278,7 +281,7 @@ public synchronized boolean detach() {
             return false;
         }

-        threadList = null;
+        javaThreadList = null;
         loadObjectList = null;

         if (isCore) {
@@ -492,7 +495,25 @@ public Address newAddress(long value) {
     /** From the BsdCDebugger interface */
     public List<ThreadProxy> getThreadList() {
       requireAttach();
-      return threadList;
+
+      if (javaThreadList == null) {
+        return null;
+      }
+      if (!isCore) {
+        // TODO: thread list is now supported for corefile only.
+        return Collections.emptyList();
+      }
+
+      if (javaThreadList.isEmpty()) {
+        Threads threads = VM.getVM().getThreads();
+        IntStream.range(0, threads.getNumberOfThreads())
+                 .mapToObj(threads::getJavaThreadAt)
+                 .forEach(javaThreadList::add);
+      }
+
+      return javaThreadList.stream()
+                           .map(t -> t.getThreadProxy())
+                           .toList();
     }

     /** From the BsdCDebugger interface */
@@ -561,21 +582,16 @@ public void doit(BsdDebuggerLocal debugger) {
     /** this functions used for core file reading and called from native attach0,
         it returns an array of long integers as
         [thread_id, stack_start, stack_end, thread_id, stack_start, stack_end, ....] for
-        all java threads recorded in Threads. Also adds the ThreadProxy to threadList */
+        all java threads recorded in Threads. */
     public long[] getJavaThreadsInfo() {
         requireAttach();
-        Threads threads = VM.getVM().getThreads();
-        int len = threads.getNumberOfThreads();
-        long[] result = new long[len * 3];    // triple
+        long[] result = new long[javaThreadList.size() * 3];    // triple
         long beg, end;
         int i = 0;
-        for (int k = 0; k < threads.getNumberOfThreads(); k++) {
-            JavaThread t = threads.getJavaThreadAt(k);
+        for (var t : javaThreadList) {
             end = t.getStackBaseValue();
             beg = end - t.getStackSize();
-            BsdThread bsdt = (BsdThread)t.getThreadProxy();
-            long uid = bsdt.getUniqueThreadId();
-            if (threadList != null) threadList.add(bsdt);
+            long uid = ((BsdThread)t.getThreadProxy()).getUniqueThreadId();
             result[i] = uid;
             result[i + 1] = beg;
             result[i + 2] = end;

-------------

PR Comment: https://git.openjdk.org/jdk/pull/28284#issuecomment-3550467374