Integrated: 8337199: Add jcmd Thread.vthread_scheduler and Thread.vthread_pollers diagnostic commands

[Alan Bateman]

On Wed, 27 Nov 2024 15:59:17 GMT, Alan Bateman <alanb at openjdk.org> wrote:

> Adds `jcmd <pid> Thread.vthread_scheduler` to print the virtual thread scheduler and `jcmd <pid> Thread.vthread_pollers` to print the I/O pollers that support virtual threads doing blocking network I/O operations.
> 
> This is a subset of the diagnostics that we've had in the loom repo for a long time. @larry-cable proposed a PR recently ([pull/22121](https://github.com/openjdk/jdk/pull/22121)) to bring a version of same into main line but it was based on an older proposal. This new PR supplants that effort.
> 
> The jtreg failure handler is updated to execute Thread.vthread_scheduler, useful capture when a test fails or times out.

This pull request has now been integrated.

Changeset: 5c8cb2ed
Author:    Alan Bateman <alanb at openjdk.org>
URL:       https://git.openjdk.org/jdk/commit/5c8cb2edcb0a919bfcad11b3f2cb399402915a0c
Stats:     391 lines in 11 files changed: 379 ins; 8 del; 4 mod

8337199: Add jcmd Thread.vthread_scheduler and Thread.vthread_pollers diagnostic commands

Reviewed-by: dholmes, kevinw

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PR: https://git.openjdk.org/jdk/pull/22414