Make terminationRequested atomic

[erikcorry]

Since terminateExecution can be called from other threads this needs to be atomic

[ask-bonk]

UnknownError: "Overloaded"

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[ask-bonk]

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[dcarney-cf]

normally for something like this, i'd go with acquire/release semantics . i guess i don't know what workerd generally goes with for this type of thing, but explicit loads and stores make atomic semantics much more clear

[jasnell]

...i guess i don't know what workerd generally goes with for this type of thing

kj::MutexGuarded<T> ... fwiw.