On Thursday, February 27, 2014 10:02:05 AM Alan Stern wrote: > On Thu, 27 Feb 2014, Rafael J. Wysocki wrote: > > > > If the child knows about the problem beforehand, it can runtime-resume > > > the parent during its ->suspend. > > > > Well, it even should do that in those cases. We may need to deal with children > > that don't do that, though. > > > > > > Well, if power.fast_suspend set guarantees that ->suspend_late, ->suspend_noirq, > > > > ->resume_noirq, and ->resume_early will be skipped for a device, then we may > > > > restrict setting it for devices whose children have it set (or that have no > > > > children). Initially, that will be equivalent to setting it for leaf devices > > > > only, but it might be extended over time in a natural way. > > > > > > Initially, maybe. > > > > Of course initially. > > > > > But it's the wrong approach in general. > > > > In the long run - I agree. > > > > > The right approach is to restrict setting fast_suspend for devices whose > > > children don't mind their parent being suspended when their resume callbacks > > > run -- not for devices whose children also have fast_suspend set. > > > > I agree, but we need to know which children are OK with the parent being > > suspended. Having fast_suspend set is a good indication of that. :-) > > > > Of course, we may introduce a separate flag for that just fine if you prefer. > > > > > That's the point I've been trying to express all along. > > > > I see. > > Okay. I'll wait to see the next version. Well, that took some time, but a new version follows. It uses two flags (see the changelog of patch [1/3]) and is reworked on top of the changes that went into 3.15-rc. Patch [2/3] is just a resend. Thanks, Rafael -- 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
