On Sun, 4 Jun 2023 18:47:13 GMT, Chris Plummer <[email protected]> wrote:
>> JdbMethodExitTest.java tries to determine the jdb threadID for the "main"
>> thread, and then later use it in jdb commands that require a threadID. It
>> does this by first having the debuggee execute the following:
>>
>> ` System.out.println("threadid="+Thread.currentThread().getId());`
>>
>> And then later on the test parses the threadID from this output. The problem
>> is that the id returned by getId() has no relation to threadIDs used by jdb,
>> which are actually JDWP ObjectIDs. In the past this has worked due to some
>> dumb luck. getID() always returns 1 for the main thread, which is always the
>> thread we are executing in. Coincidentally the JDWP ObjectID for the main
>> Thread object is also always 1 because this is the first ObjectID that the
>> debug agent ever needs to create. However, when the debuggee main thread is
>> a virtual thread, neither getId() nor JDWP assign 1 to the threadID, and in
>> fact both will end up with very different values for the threadID. The end
>> result is errors from jdb for using an invalid threadID.
>>
>> The correct threadID can be obtained by executing the jdb "threads" command
>> and parsing it from a line that looks like the following:
>>
>> ` (java.lang.VirtualThread)694 main running (at breakpoint)`
>>
>> Note this test will also fail due to
>> [JDK-8309334](https://bugs.openjdk.org/browse/JDK-8309334), which should be
>> fixed first.
>>
>> I've tested with mach5 tier5 in a workspace that has integrated the various
>> CRs mentioned. Once JDK-8309334 is fixed, before integrating this PR I'll
>> first merge and verify that the test being removed from the problem list by
>> this PR also passes.
>
> Chris Plummer has updated the pull request with a new target base due to a
> merge or a rebase. The pull request now contains four commits:
>
> - fix minor merge issue
> - merge
> - remove test from problem list
> - properly determine the main threadId
Looks good.
Thanks,
Serguei
-------------
Marked as reviewed by sspitsyn (Reviewer).
PR Review: https://git.openjdk.org/jdk/pull/14294#pullrequestreview-1465846971
