8374190: Convert ConcurrentHashTable atomic lists to use Atomic<T>

[kimbarrett]

Please review this change to ConcurrentHashTable to use Atomic<Node*> for
the Node lists. Note that this does not complete the replacement of direct
uses of AtomicAccess by that class; there's still one more group remaining.

Testing: mach5 tier1-3

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Issue

• JDK-8374190: Convert ConcurrentHashTable atomic lists to use Atomic<T> (Enhancement - P4)

Reviewers

• David Holmes (@dholmes-ora - Reviewer)

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[openjdk]

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

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8374190: Convert ConcurrentHashTable atomic lists to use Atomic<T>

Reviewed-by: dholmes

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At the time when this comment was updated there had been 10 new commits pushed to the master branch:

• a0094f5: 8374216: Assorted changes to jpackage without functional impact
• ecb4234: 8373447: Suspicious sign extension after integer promotion in imageDecompressor.cpp
• 4b8eda3: 8373983: java/util/Locale/UseOldISOCodesTest.java fails with JTREG_AOT_JDK=onestep
• ... and 7 more: https://git.openjdk.org/jdk/compare/9435d5b89ca08595f0f2f8d029c00bc6d1f30104...master

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[mlbridge]

Webrevs

• 00: Full (0278f373)

[dholmes-ora]

This all seems reasonable.

Thanks

[dholmes-ora]

The const part of the comment no longer seems relevant.

[kimbarrett]

The const is still relevant, for the reason described. It's at least
arguable that it's kind of sketchy to do this. It certainly took me a bit of
study to understand. Note that I moved the position of the const qualifier
to its more usual location (in our code) for declaring a constant object (the
Atomic<Node*> is atomic). It could instead be written as Atomic<Node*> const*,
retaining the ordering from the original. Also see the implementation, where
we need to cast away the const qualifier, which is now being done with
const_cast rather than a C-style cast (that was also stripping off the volatile
qualifier, which the use of AtomicAccess implicitly reapplied).