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> + /* > + * Ensure that only one instance is doing MM CID operations within > + * a MM. The common case is uncontended. The rare fixup case adds > + * some overhead. > + */ > + scoped_guard(mutex, &mm->mm_cid.mutex) { When exiting from a mm where mm->mm_cid.users == 1 (read with READ_ONCE()), can we do this without holding the mutex as an optimization ? > + * Synchronize eventally pending work to ensure that there are no eventually Thanks, Mathieu -- Mathieu Desnoyers EfficiOS Inc. https://www.efficios.com