On Wednesday 20 January 2010, Oliver Neukum wrote: > Am Mittwoch, 20. Januar 2010 00:17:51 schrieb Benjamin Herrenschmidt: > > On Tue, 2010-01-19 at 10:04 +0100, Bastien ROUCARIES wrote: > > > Instead of masking bit could we only check if incompatible flags are > > > used during suspend, and warm deeply. Call stack will be therefore > > > identified, and we could have some metrics about such problem. > > > > > > It will be a debug option like lockdep but pretty low cost. > > > > I still believe it would just be a giant can of worms to require every > > call site of memory allocators to "know" whether suspend has been > > started or not.... Along the same reasons why we added that stuff for > > boot time allocs. > > But we have the freezer. So generally we don't require that knowledge. > We can expect no normal IO to happen. > The question is in the suspend paths. We never may use anything > but GFP_NOIO (and GFP_ATOMIC) in the suspend() path. We can > take care of that requirement in the allocator only if the whole system > is suspended. As soon as a driver does runtime power management, > it is on its own. If you start new kernel threads using the async framework, for example, GFP_KERNEL allocations are going to be used. As I said before, IMnshO , duplicating every piece of code that allocates memory and can be run during suspend/resume as well as in other circumstances doesn't make sense. Rafael _______________________________________________ linux-pm mailing list linux-pm@xxxxxxxxxxxxxxxxxxxxxxxxxx https://lists.linux-foundation.org/mailman/listinfo/linux-pm
