8356556: AArch64: No need for acquire fence in safepoint poll in FFM

[toxaart]

Hi, please consider the following changes:

On AArch64, the acquire bool argument of the safepoint_poll() method is removed, as the load-acquire ldar instruction in the safepoint_poll() implementation is not needed completely. It was used for observing the disarmed value when VMThread was used to disarm the Java threads, but currently JavaThreads disarm themselves.

Tested in tiers 1 - 4.

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Progress

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Issue

• JDK-8356556: AArch64: No need for acquire fence in safepoint poll in FFM (Enhancement - P4)

Reviewers

• Patricio Chilano Mateo (@pchilano - Reviewer) Review applies to 7a639980
• David Holmes (@dholmes-ora - Reviewer)

Reviewing

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[bridgekeeper]

👋 Welcome back toxaart! A progress list of the required criteria for merging this PR into master will be added to the body of your pull request. There are additional pull request commands available for use with this pull request.

[openjdk]

@toxaart This change now passes all automated pre-integration checks.

ℹ️ This project also has non-automated pre-integration requirements. Please see the file CONTRIBUTING.md for details.

After integration, the commit message for the final commit will be:

8356556: AArch64: No need for acquire fence in safepoint poll in FFM

Reviewed-by: dholmes, pchilanomate

You can use pull request commands such as /summary, /contributor and /issue to adjust it as needed.

At the time when this comment was updated there had been 33 new commits pushed to the master branch:

• f62f117: 8359701: G1: Move heap expansion time tracking of G1CollectedHeap:expand to call site
• a082082: 8354650: [PPC64] Try to reduce register definitions
• f7cd3fa: 8332623: Remove setTTL()/getTTL() methods from DatagramSocketImpl/MulticastSocket and MulticastSocket.send(DatagramPacket, byte)
• ... and 30 more: https://git.openjdk.org/jdk/compare/e8ef93ae9de624f25166bdf010c915672b2c5cf4...master

As there are no conflicts, your changes will automatically be rebased on top of these commits when integrating. If you prefer to avoid this automatic rebasing, please check the documentation for the /integrate command for further details.

As you do not have Committer status in this project an existing Committer must agree to sponsor your change. Possible candidates are the reviewers of this PR (@pchilano, @dholmes-ora) but any other Committer may sponsor as well.

➡️ To flag this PR as ready for integration with the above commit message, type /integrate in a new comment. (Afterwards, your sponsor types /sponsor in a new comment to perform the integration).

[openjdk]

@toxaart The following label will be automatically applied to this pull request:

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[mlbridge]

Webrevs

• 01: Full - Incremental (6120a1e3)
• 00: Full (7a639980)

[pchilano]

LGTM, thanks.

[dholmes-ora]

Overall looks good, but one nit.

Thanks

[dholmes-ora]

LGTM. Thanks

[toxaart]

/integrate

[openjdk]

@toxaart
Your change (at version 6120a1e) is now ready to be sponsored by a Committer.

[coleenp]

It also looks good.
/sponsor

[openjdk]

Going to push as commit c1deb9e.
Since your change was applied there have been 33 commits pushed to the master branch:

• f62f117: 8359701: G1: Move heap expansion time tracking of G1CollectedHeap:expand to call site
• a082082: 8354650: [PPC64] Try to reduce register definitions
• f7cd3fa: 8332623: Remove setTTL()/getTTL() methods from DatagramSocketImpl/MulticastSocket and MulticastSocket.send(DatagramPacket, byte)
• ... and 30 more: https://git.openjdk.org/jdk/compare/e8ef93ae9de624f25166bdf010c915672b2c5cf4...master

Your commit was automatically rebased without conflicts.

[theRealAph]

/sponsor

[openjdk]

@coleenp @toxaart Pushed as commit c1deb9e.

💡 You may see a message that your pull request was closed with unmerged commits. This can be safely ignored.

[openjdk]

@theRealAph The command sponsor can only be used in open pull requests.