RFR: 8335743: jhsdb jstack cannot print some information on the waiting thread [v2]

[David Holmes]

On Mon, 8 Jul 2024 12:16:51 GMT, KIRIYAMA Takuya <duke at openjdk.org> wrote:

>> This bug was introduced by JDK-8284161. "Object.wait (long timeoutMillis)" was changed to call "Object.wait0 (long timeoutMillis)" in JDK-8284161.
>> 
>> When "jhdsb jstack" is executed, the stack and lock information are printed in "sun.jvm.hotspot.runtime.JavaVFrame.printLockInfo(PrintStream tty, int frameCount)". This method checks whether the method is java.lang.Object.wait (...) and then reports the waitstate only if the check passes.
>> https://github.com/openjdk/jdk/blob/7bc8f9c150cbf457edf6144adba734ecd5ca5a0f/src/jdk.hotspot.agent/share/classes/sun/jvm/hotspot/runtime/JavaVFrame.java#L103
>> 
>> 
>>       if (getMethod().getName().asString().equals("wait") &&
>>           getMethod().getMethodHolder().getName().asString().equals("java/lang/Object")) {
>> 
>> 
>> However, after JDK-8284161, the waiting thread waits on "java.lang.Object.wait0 (long timeoutMillis)", so it no longer reports the waitstate.
>> 
>> I changed "printLockInfo(PrintStream tty, int frameCount)" to check for "java.lang.Object.wait0 (...)".
>> I confirmed that the lock information is correctly printed with this fix.
>> I tested hotspot/jtreg/serviceability/sa/ and jdk/sun/tools/jhsdb/heapconfig/, and there were no regressions by this fix.
>> 
>> Would anyone review this change, please?
>
> KIRIYAMA Takuya has updated the pull request incrementally with one additional commit since the last revision:
> 
>   8335743: jhsdb jstack cannot print some information on the waiting thread

Update looks good. Thanks

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Marked as reviewed by dholmes (Reviewer).

PR Review: https://git.openjdk.org/jdk/pull/20049#pullrequestreview-2168167270