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[...] > Should sh.go be set with smp_store_release(&sh.go, true) (or preceded by > smp_mb()) so the pre-activation reads in check_lazy_counter() complete before > the paused workers resume modifying pct? Yes, this is a bug in the test. Nothing orders the reads of the counter in check_lazy_counter() before the store to sh.go. On arm64 or POWER, a worker can see go set and update the counter before those reads complete. The check then fails, although the library is correct. x86 does not reorder a load with a later store, so our test runs could not hit it. Planned fix for the next round: the test sets go with smp_store_release(), and the workers read it with smp_load_acquire(). Thanks, Mathieu -- Mathieu Desnoyers EfficiOS Inc. https://www.efficios.com