On 11/23, Peter Zijlstra wrote: > > Ah,. uhm,. you mean, not do anything at all? > > Dunno, really, let me try and read the code there. Thanks. This is very minor of course, but it would be nice to undestand the reason. To me it looks unneeded, but I don't trust myself. (snippets from my previous email below). With or without this change, even if we know that rq->idle is running we can't know if it (say) already started play_dead_common() or not. We are going to call __cpu_die(), afaics it should do the necessary synchronization in any case. For example, native_cpu_die() waits for cpu_state == CPU_DEAD in a loop. Of course it should work in practice (it also does msleep), but in theory there is no guarantee. So. Can't we just remove this wait-loop? We know that rq->idle will be scheduled "soon", I don't understand why it is necessary to ensure that context_switch() has already happened. Oleg. -- To unsubscribe from this list: send the line "unsubscribe linux-tip-commits" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
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