Marcelo Tosatti wrote: > Jan, > > This was suggested but we thought it might be safer to keep the > get_cpu/put_cpu pair in case -rt kernels require it (which might be > bullshit, but nobody verified).
-rt stumbles over both patterns (that's why I stumbled over it in the first place: get_cpu disables preemption, but spin_lock is a sleeping lock under -rt) and actually requires requests_lock to become raw_spinlock_t. Reordering get_cpu and spin_lock would be another option, but not really a gain for both scenarios. So unless there is a way to make the whole critical section preemptible (thus migration-agnostic), I think we can micro-optimize it like this. Jan -- Siemens AG, Corporate Technology, CT SE 2 Corporate Competence Center Embedded Linux -- To unsubscribe from this list: send the line "unsubscribe kvm" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
