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If someone can > come in and convince us that the PREEMPT_RT way is also beneficial for > the non-RT case then we can make it consistent again. Until then, this > change is focusing on fixing PREEMPT_RT, and that's what the patch is > going to be limited to. Here is one additional thing to keep in mind: although SRCU-fast is probably quite fast (as the name implies), last time I tried using migrate disable in a fast path I was surprised to see verbosity of the generated assembly, and how slow it was compared to preempt disable. So before using migrate disable on a fast path, at least on non-preempt-RT configs, we should carefully consider the performance impact of migrate disable. Thanks, Mathieu -- Mathieu Desnoyers EfficiOS Inc. https://www.efficios.com