8276129: PretouchTask should page-align the chunk size

[kimbarrett]

Please review this change to PretouchTask to page-align the chunk size.
Aligning down is used because it's easy; aligning up would require dealing
with possible overflow or verifying that overflow isn't possible.

Testing:
mach5 tier1

Locally (linux-x64) java -version with pretouch task logging and various
chunk sizes, manually verifying the number of workers was as expected.

---

Progress

• Change must not contain extraneous whitespace
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Issue

• JDK-8276129: PretouchTask should page-align the chunk size

Reviewers

• Stefan Karlsson (@stefank - Reviewer) ⚠️ Review applies to ce8ad82
• Thomas Schatzl (@tschatzl - Reviewer) ⚠️ Review applies to ee12018

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[openjdk]

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[mlbridge]

Webrevs

• 02: Full - Incremental (d1b3048c)
• 01: Full - Incremental (ce8ad82b)
• 00: Full (ee12018b)

[stefank]

This looks like a place where align_down_bounded could be used. Something like this:

size_t chunk_size = align_down_bounded(PretouchTask::chunk_size(), page_size);

[kimbarrett]

I either forgot about or never noticed that function. Changed to use it.

[openjdk]

@kimbarrett 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:

8276129: PretouchTask should page-align the chunk size

Reviewed-by: stefank, tschatzl

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At the time when this comment was updated there had been 1 new commit pushed to the master branch:

• a472433: 8276572: Fake libsyslookup.so library causes tooling issues

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[tschatzl]

Lgtm independent of whether you want to incorporate @stefank 's suggestion.

[kimbarrett]

Thanks @stefank and @tschatzl for reviews.

[kimbarrett]

/integrate

[openjdk]

Going to push as commit 0e0dd33.
Since your change was applied there has been 1 commit pushed to the master branch:

• a472433: 8276572: Fake libsyslookup.so library causes tooling issues

Your commit was automatically rebased without conflicts.

[openjdk]

@kimbarrett Pushed as commit 0e0dd33.

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