RFR: 8364638: Refactor and make accumulated GC CPU time code generic [v5]

[Albert Mingkun Yang]

On Fri, 15 Aug 2025 06:57:04 GMT, Stefan Johansson <sjohanss at openjdk.org> wrote:

>  I don't think it should be a warning on the OS API though.

Agree. At this level, returning `-1` already indicates the error -- callers should/can check the return-value and act on it.

> ... could be added to CPUTimeThreadClosure::do_thread(...)

There are dozens of callers though; `CPUTimeThreadClosure` is just one. For this particular patch, I think emitting some msg/warning somewhere inside `static void log_cpu_time` may be enough. WDYT?

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PR Review Comment: https://git.openjdk.org/jdk/pull/26621#discussion_r2278499043