8342482: Use the same native thread initialization procedure on all platforms

[dholmes-ora]

This fixes an issue reported in https://bugs.openjdk.org/browse/JDK-8340401 caused by a difference in the thread initialization protocol for new Java threads, by using the same Monitor-based "handshake" protocol on all platforms. This allows all the related code, including the _threadStart_lock to be put into the shared OSThreadBase class.

For AIX and Windows this means threads are no longer started in a suspended state.

Testing

• GHA
• Tiers 1-4

Thanks

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Progress

• [ ] Change must be properly reviewed (1 review required, with at least 1 Reviewer)
• [x] Change must not contain extraneous whitespace
• [x] Commit message must refer to an issue

Issue

• JDK-8342482: Use the same native thread initialization procedure on all platforms (Enhancement - P4)

Reviewing

Using git

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$ git fetch https://git.openjdk.org/jdk.git pull/21558/head:pull/21558
$ git checkout pull/21558

Update a local copy of the PR:
$ git checkout pull/21558
$ git pull https://git.openjdk.org/jdk.git pull/21558/head

Using Skara CLI tools

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$ git pr checkout 21558

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$ git pr show -t 21558

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https://git.openjdk.org/jdk/pull/21558.diff