On Tue, 2008-11-04 at 09:54 +0100, Rafael J. Wysocki wrote: > To handle this, I need to know two things: > 1) what changes of the zones are possible due to memory hotplugging > (i.e. can they grow, shring, change boundaries etc.) All of the above. > 2) what kind of locking is needed to prevent zones from changing. The amount of locking is pretty minimal. We depend on some locking in sysfs to keep two attempts to online from stepping on the other. There is the zone_span_seq*() set of functions. These are used pretty sparsely, but we do use them in page_outside_zone_boundaries() to notice when a zone is resized. There are also the pgdat_resize*() locks. Those are more for internal use guarding the sparsemem structures and so forth. Could you describe a little more why you need to lock down zone resizing? Do you *really* mean zones, or do you mean "the set of memory on the system"? Why walk zones instead of pgdats? -- Dave _______________________________________________ linux-pm mailing list linux-pm@xxxxxxxxxxxxxxxxxxxxxxxxxx https://lists.linux-foundation.org/mailman/listinfo/linux-pm
