RFR: 8370176: Mixed mode jhsdb jstack cannot unwind call stack with -Xcomp [v2]

[Chris Plummer]

On Mon, 20 Oct 2025 06:59:42 GMT, Yasumasa Suenaga <ysuenaga at openjdk.org> wrote:

>> `jhsdb jstack --mixed` would not work when attaches to the process runs with `-Xcomp`.
>> 
>> It has been reported by @pchilano in #27728. You can reproduce the problem with [Test.java (attached JBS)](https://bugs.openjdk.org/secure/attachment/116551/Test.java). You can see following stack.
>> 
>> 
>> ----------------- 646689 -----------------
>> "Thread-0" #24 prio=5 tid=0x00007f1cec18c890 nid=646689 waiting on condition [0x00007f1cd0158000]
>>    java.lang.Thread.State: TIMED_WAITING (sleeping)
>>    JavaThread state: _thread_blocked
>> 0x00007f1cf3b7f462 __syscall_cancel_arch + 0x32
>> 0x00007f1cf3b7375c __internal_syscall_cancel + 0x5c
>> 0x00007f1cf3b766a8 ___pthread_cond_timedwait + 0x178
>> 0x00007f1cf270e1e9 PlatformEvent::park_nanos(long) + 0x119
>> 0x00007f1cf2005f4c JavaThread::sleep_nanos(long) + 0xfc
>> 0x00007f1cf218789f JVM_SleepNanos + 0x28f
>> 0x00007f1cdb95f299 java.lang.Thread.sleepNanos0(long) + 0x99 (Native method)
>> 
>> 
>> `Thread.sleepNanos0` is the bottom stack, but actually it has more call frames. You can see them with `-XX:+PreserveFramePointer`.
>> 
>> 
>> ----------------- 646841 -----------------
>> "Thread-0" #24 prio=5 tid=0x00007f4a0018c9e0 nid=646841 waiting on condition [0x00007f49e4fd7000]
>>    java.lang.Thread.State: TIMED_WAITING (sleeping)
>>    JavaThread state: _thread_blocked
>> 0x00007f4a0aa29462 __syscall_cancel_arch + 0x32
>> 0x00007f4a0aa1d75c __internal_syscall_cancel + 0x5c
>> 0x00007f4a0aa206a8 ___pthread_cond_timedwait + 0x178
>> 0x00007f4a0970e1e9 PlatformEvent::park_nanos(long) + 0x119
>> 0x00007f4a09005f4c JavaThread::sleep_nanos(long) + 0xfc
>> 0x00007f4a0918789f JVM_SleepNanos + 0x28f
>> 0x00007f49ef961099 java.lang.Thread.sleepNanos0(long) + 0x99 (Native method)
>> 0x00007f49e7f477b4 * java.lang.Thread.sleepNanos(long) bci:33 line:509 (Compiled frame)
>> 0x00007f49e7f41a64 * java.lang.Thread.sleep(long) bci:25 line:540 (Compiled frame)
>> 0x00007f49e7f4037c * Test.run() bci:3 line:6 (Compiled frame)
>> 0x00007f49ef943328 * java.lang.Thread.runWith(java.lang.Object, java.lang.Runnable) bci:5 line:1487 (Compiled frame)
>>                         * java.lang.Thread.run() bci:19 line:1474 (Compiled frame)
>> 0x00007f49ef3385fd <StubRoutines (initial stubs)>
>> 0x00007f4a08fc247e JavaCalls::call_helper(JavaValue*, methodHandle const&, JavaCallArguments*, JavaThread*) + 0x4ce
>> 0x00007f4a08fc2bb3 JavaCalls::call_virtual(JavaValue*, Klass*, Symbol*, Symbol*, JavaCallArguments*, JavaThread*) + 0x2d3
>> 0x00007f4a08fc31bb JavaCalls::call_virtu...
>
> Yasumasa Suenaga has updated the pull request incrementally with one additional commit since the last revision:
> 
>   Update testcase

test/hotspot/jtreg/serviceability/sa/TestJhsdbJstackMixedWithXComp.java line 40:

> 38:  * @bug 8370176
> 39:  * @requires vm.hasSA
> 40:  * @requires os.family == "linux"

Do Windows and OSX have a similar problem that should be fixed also?

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

PR Review Comment: https://git.openjdk.org/jdk/pull/27885#discussion_r2445943475