On 7/4/07, Paul Mackerras <paulus@xxxxxxxxx> wrote:
Rafael J. Wysocki writes: > They are mostly related to kernel threads, that we've already agreed no to > freeze (except for the ones that want that, but they will be responsible for > getting everything right). The initial patches for that are in -mm and more > will come. Serious question: which kernel threads would actually want to be frozen? Threads that do no I/O at all don't care about suspend/resume and don't need to be frozen in any case. Threads that issue I/O requests in order to service incoming I/O requests can't be frozen because of the possibility of deadlock. Which leaves threads that do I/O just for the fun of it. :) What am I missing?
I like kseriod and kgameportd to be frozen. If fast resume of serio port fails we kick the task of full resume to kseriod. But when we hibernate and all the devices are resumed again so snapshot can be written I don't care if touchpad failed to resume - it can be dealt with later, when system is actually resumes. So I like that by freezing I do not delay hibernation and all requests get simply discarded as they are not in the image. This mostly affects hibernation though. Having these threads frozen also guarantees that serio/gameport device tree is stable during susped/resume and I can process outstanding requests later, when system is fully up. -- Dmitry _______________________________________________ linux-pm mailing list linux-pm@xxxxxxxxxxxxxxxxxxxxxxxxxx https://lists.linux-foundation.org/mailman/listinfo/linux-pm
