> But I think we'd be best off stashing a single bit somewhere and > checking it at migrate time (relatively infrequent) rather than > copying and zeroing out a potentially enormous affinity mask every > time we disable migration (often, and in fast paths). Perhaps adding > TASK_PINNED to the task state flags would do it?
It would need to be a count to be able to nest it. > > get_cpu() etc. could be changed to use this then too. > > Some users of get_cpu might be relying on it to avoid actual > preemption. In other words, we should have introduced a > migrate_disable() when we first discovered the preempt/per_cpu > conflict. Ok perhaps it would make sense to migrate it step by step :- define a replacement for get_cpu and migrate over as users are getting audited and eventually deprecate old one. -Andi - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
