On Tue, 15 Dec 2009, Rafael J. Wysocki wrote: > > > > Give a real example that matters. > > I'll try. Let -> denote child-parent relationships and assume dpm_list looks > like this: No. I mean something real - something like - if you run on a non-PC with two USB buses behind non-PCI controllers. - device xyz. > If this applies to _resume_ only, then I agree, but the Arjan's data clearly > show that serio devices take much more time to suspend than USB. I mean in general - something where you actually have hard data that some device really needs anythign more than my one-liner, and really _needs_ some complex infrastructure. Not "let's imagine a case like xyz". > But if we only talk about resume, the PCI bridges don't really matter, > because they are resumed before all devices that depend on them, so they don't > really need to wait for anyone anyway. But that's my _point_. That's the whole point of the one-liner patch. Read the comment above that one-liner. My whole point was that by doing the whole "wait for children" in generic code, you also made devices - such as PCI bridges - have to wait for children, even though they don't need to, and don't want to. So I suggested an admittedly ugly hack to take care of it - rather than some complex infrastructure. Linus -- To unsubscribe from this list: send the line "unsubscribe linux-acpi" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html