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As the fixup is complete the > potential exhaustion of the CID pool is not longer possible, so the CID can > be transferred to the scheduling out task or to the CPU depending on the > current ownership mode. This is now possible because mm_cid::mode contains > both the ownership state and the transition bit so the racy snapshot is > valid under all circumstances because a subsequent modification of the > mode is serialized by the corresponding runqueue lock. AFAIU the mc->mode updates are serialized by the mm->mm_cid.lock and not the runqueue locks. What am I missing ? [...] > + /* > + * If transition mode is done, transfer ownership when the CID is > + * within the convergion range. Otherwise the next schedule in will convergence > + * have to allocate or converge add final ".". Thanks, Mathieu -- Mathieu Desnoyers EfficiOS Inc. https://www.efficios.com