Hi, On Monday, 9 April 2007 16:03, Pavel Machek wrote: > > Currently, we use the CPU hotplug to disable nonboot CPUs in the suspend > > code > > paths, but with the recent change of code ordering (ie. nonboot CPUs are > > disabled after freezing tasks _and_ devices) it has become quite > > troublesome. > > The reason of this is that there are some CPU hotplug notifiers registered > > and > > called on each run of cpu_up()/cpu_down() that assume the system to be fully > > functional, which is not the case during the suspend. Moreover, at least > > some > > of them do things that are not really necessary for disabling or enabling > > the > > nonboot CPUs. > > Right. > > > The advantage of using the CPU hotplug (in its current form) for suspending > > is > > that if some CPUs don't reappear during the resume, we are safe. Still, I > > think it would be more appropriate, and simpler in the long run, to notify > > the > > interested subsystems _only_ if one (or more) CPUs are not functional after > > the > > resume. > > I'm afraid that adding 'cpu not there so simulate unplug' path will > make it complex, and prone to failure, as _noone_ is going to test it.
Does it mean you think we should stick with the current approach and sort out all issues as they show up, or should we go for not using the CPU hotplug for suspending without implementing the 'cpu not there so simulate unplug' path at all (eg. we can fail the resume instead)? Rafael - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
