RFR: 8344165: Trace exceptions with a complete call-stack [v13]

[David Holmes]

On Wed, 25 Jun 2025 22:41:53 GMT, Ioi Lam <iklam at openjdk.org> wrote:

>> This PR makes it easier to analyze exceptions without modifying the JVM or the app to print call stacks:
>> 
>> Excerpt from the test case ExceptionsTest.java. 
>> 
>> 
>> [0.042s][info][exceptions] Exception <a 'java/lang/RuntimeException'{0x0000000474019530}: Test exception 1 for logging>
>> [                        ]  thrown in interpreter method <{method} {0x000079e52c4005b0} 'bar' '()V' in 'ExceptionsTest$InternalClass'>
>> [                        ]  at bci 9 for thread 0x000079e58c02c7b0 (main)
>> [0.042s][info][exceptions,stacktrace] Exception <a 'java/lang/RuntimeException'{0x0000000474019530}: Test exception 1 for logging>
>> [0.042s][info][exceptions,stacktrace] 	at ExceptionsTest$InternalClass.bar(ExceptionsTest.java:110)
>> [0.042s][info][exceptions,stacktrace] 	at ExceptionsTest$InternalClass.foo(ExceptionsTest.java:105)
>> [0.042s][info][exceptions,stacktrace] 	at ExceptionsTest$InternalClass.main(ExceptionsTest.java:100)
>> [0.042s][info][exceptions           ] Found matching handler for exception of type "java.lang.RuntimeException" in method "bar" at BCI: 10
>> Exception 1 caught.
>> 
>> 
>> - Note that the old `[exceptions]` log  is triggered by `InterpreterRuntime::exception_handler_for_exception()` and prints one level of the stack while the interpreter is looking for a handler. However, once a handler is found (inside `bar()`), the `[exceptions]` log terminates, and we do not know about the `foo()` or `main()` methods.
>> 
>> - The `[exceptions,stacktrace]` log is printed only when an exception is thrown:
>>     - By an `_athrow` bytecode. See comments around `Exceptions::log_exception_stacktrace(Handle exception, methodHandle method, int bci)`
>>     - By native code in Exceptions::special_exception() and  and Exceptions::_throw()).
>> 
>> **Concurrent Exceptions**
>> 
>> Neither the old  `[exceptions]` or the new `[exceptions,stacktrace]` logs distinguish between multiple exceptions that are thrown and handled concurrently. The users should use something like `-Xlog:exceptions,exceptions+stack::tags,tid` to include the thread ID into the log output, and use an external tool (such as a script) to demultiplex the logs.
>
> Ioi Lam has updated the pull request with a new target base due to a merge or a rebase. The incremental webrev excludes the unrelated changes brought in by the merge/rebase. The pull request contains 15 additional commits since the last revision:
> 
>  - Merge branch 'master' into 8358080-print-thread-stack-with-xlog-exceptions-trace
>  - Fix crash in runtime/logging/RedefineClasses.java: cannot print stack trace in Exceptions::special_exception()
>  - @coleenp comments: Removed dead code
>  - @coleenp and @dholmes-ora comments
>  - @coleenp comments; Also, use ProcessTools.executeProcess() to log the output in files
>  - refactor
>  - Reimplement -- print stack trace only when it is a known throwing site
>  - @dholmes-ora comments -- removed printing of output.getStdout() from test
>  - Print callstack for rethrown exceptions
>  - @dholmes-ora comments - use JavaThread::current() instead
>  - ... and 5 more: https://git.openjdk.org/jdk/compare/ff922b51...3eb7c622

Marked as reviewed by dholmes (Reviewer).

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PR Review: https://git.openjdk.org/jdk/pull/25522#pullrequestreview-2960063811