RFR: 8273635: Attempting to acquire lock StackWatermark_lock/9 out of order with lock tty_lock/3 [v2]

[Erik Österlund]

On Mon, 13 Sep 2021 22:24:50 GMT, Coleen Phillimore <coleenp at openjdk.org> wrote:

>> This change reverts the rank ordering of ttyLock and StackWatermark_lock because the latter is held through a very large region and printing all of this to a buffer with xmlstream is non-trivial.
>> With this change, if tty->print_cr() is done while holding the stackwatermark lock or lower (which is service ranking, etc), a lock inversion will happen with ttyLock.  This doesn't happen now because all the code in GC and much of the rest of the runtime use UL and not tty->print().
>> Tested with tier1-6.
>
> Coleen Phillimore has updated the pull request incrementally with one additional commit since the last revision:
> 
>   fix typo

The rank reversal looks good. Too bad there was more printing code.

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Marked as reviewed by eosterlund (Reviewer).

PR: https://git.openjdk.java.net/jdk/pull/5499