Hi, On Wednesday, 14 February 2007 15:40, Gautham R Shenoy wrote: > Hello Everybody, > > This is an experiment towards process_freezer based implementation > of cpu-hotplug. This is mainly based on ideas of Andrew Morton, > Ingo Molnar and Paul Mckenney featured in the discussion > http://lkml.org/lkml/2007/1/31/323. > > This is an absolute bare-minimal implementation to check the feasibility > of using process freezer for cpu-hotplug. > > The patchset comprises of four patches. > o PATCH 1/4: Core implementation of freezer-based-hotplug. > o PATCH 2/4: Revert changes to workqueue to make it work with the > freezer-cpu-hotplug. > o PATCH 3/4: Eliminate hotcpu subsystem mutexes from sched and slab. > o PATCH 4/4: Eliminate lock_cpu_hotplug from the kernel.
I think two things are missing: 1) We should make sure there are not PF_NOFREEZE tasks running when a CPU is removed (when one is added probably too). For this purpose we can add a parameter to freeze_processes() that will tell it to ignore PF_NOFREEZE, but at the same time we'll have to change all kernel threads that set PF_NOFREEZE to call try_to_freeze() anyway. I can do that, but it will take me a couple of days. 2) We have to change the PM code to stop using CPU hotplug for disabling nonboot CPUs. ;-) Greetings, 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/
