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

[spchee]

Removes the unnecessary acquire to reduce memory ordering requirement since it is not longer needed as threads always disarm their own poll value.

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Progress

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

Error

 ⚠️ OCA signatory status must be verified

Warnings

 ⚠️ Patch contains a binary file (src/java.desktop/share/classes/java/awt/doc-files/BorderLayout-1.gif)
 ⚠️ Patch contains a binary file (src/java.desktop/share/classes/java/awt/doc-files/FlowLayout-1.gif)
 ⚠️ Patch contains a binary file (src/java.desktop/share/classes/java/awt/doc-files/GridBagLayout-1.gif)
 ⚠️ Patch contains a binary file (src/java.desktop/share/classes/java/awt/doc-files/GridBagLayout-2.gif)
 ⚠️ Patch contains a binary file (src/java.desktop/share/classes/java/awt/doc-files/GridLayout-1.gif)
 ⚠️ Patch contains a binary file (src/java.desktop/share/classes/java/awt/doc-files/GridLayout-2.gif)

Issue

• JDK-8356556: AArch64: No need for acquire fence in safepoint poll in FFM (Enhancement - P4) ⚠️ Issue is already resolved. Consider making this a "backport pull request" by setting the PR title to Backport <hash> with the hash of the original commit. See Backports.

Reviewing

Using git

Checkout this PR locally:
$ git fetch https://git.openjdk.org/jdk.git pull/25211/head:pull/25211
$ git checkout pull/25211

Update a local copy of the PR:
$ git checkout pull/25211
$ git pull https://git.openjdk.org/jdk.git pull/25211/head

Using Skara CLI tools

Checkout this PR locally:
$ git pr checkout 25211

View PR using the GUI difftool:
$ git pr show -t 25211

Using diff file

Download this PR as a diff file:
https://git.openjdk.org/jdk/pull/25211.diff

[bridgekeeper]

Hi @spchee, welcome to this OpenJDK project and thanks for contributing!

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[spchee]

/covered

[bridgekeeper]

Thank you! Please allow for a few business days to verify that your employer has signed the OCA. Also, please note that pull requests that are pending an OCA check will not usually be evaluated, so your patience is appreciated!

[openjdk]

❗ This change is not yet ready to be integrated.
See the Progress checklist in the description for automated requirements.

[openjdk]

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

• hotspot

When this pull request is ready to be reviewed, an "RFR" email will be sent to the corresponding mailing list. If you would like to change these labels, use the /label pull request command.

[openjdk]

@spchee this pull request can not be integrated into master due to one or more merge conflicts. To resolve these merge conflicts and update this pull request you can run the following commands in the local repository for your personal fork:

git checkout safepoint_acq
git fetch https://git.openjdk.org/jdk.git master
git merge FETCH_HEAD
# resolve conflicts and follow the instructions given by git merge
git commit -m "Merge master"
git push

[bridgekeeper]

@spchee This pull request has been inactive for more than 4 weeks and will be automatically closed if another 4 weeks passes without any activity. To avoid this, simply issue a /touch or /keepalive command to the pull request. Feel free to ask for assistance if you need help with progressing this pull request towards integration!

[spchee]

/touch
Waiting for OCA approval!!!

[openjdk]

@spchee The pull request is being re-evaluated and the inactivity timeout has been reset.