On Mon, May 31, 2010 at 04:26:17PM -0700, mark gross wrote: > On Mon, May 31, 2010 at 11:38:55PM +0200, Rafael J. Wysocki wrote: > > On Monday 31 May 2010, Arve Hjønnevåg wrote: > > > 2010/5/29 Alan Stern <stern@xxxxxxxxxxxxxxxxxxx>: > > > > On Sat, 29 May 2010, Arve Hjønnevåg wrote: > > > > > > > >> > In place of in-kernel suspend blockers, there will be a new type of QoS > > > >> > constraint -- call it QOS_EVENTUALLY. It's a very weak constraint, > > > >> > compatible with all cpuidle modes in which runnable threads are allowed > > > >> > to run (which is all of them), but not compatible with suspend. > > > >> > > > > >> This sound just like another API rename. It will work, but given that > > > >> suspend blockers was the name least objectionable last time around, > > > >> I'm not sure what this would solve. > > > > > > > > It's not just a rename. By changing this into a QoS constraint, we > > > > make it more generally useful. Instead of standing on its own, it > > > > becomes part of the PM-QOS framework. > > > > > > > > > > We cannot use the existing pm-qos framework. It is not safe to call > > > from atomic context. > > > > We've just merged a patch that fixed that if I'm not mistaken. Mark, did your > > PM QoS update fix that? > > > > I'm pretty sure it can be called in atomic context, and if its not I'm > sure we can fix that. It can be called in atomic context. I don't > think it was ever a problem to call it in atomic context. The problem it > had was that crappy list of string compares. Thats been fixed. > um, the notifiers that are currently used may not be cool in atomic context :( --mgross > --mgross > > > > Also, it does not have any state constraints, so it iterates over every > > > registered constraint each time one of them changes. > > > > That's fixable IMO. > > > > > Nor does is currently provide any stats for debugging. > > > > That's why Alan is proposing to add that. > > > > > The original wakelock patchset supported a wakelock type so it could > > > be used to block more then suspend, but I had to remove this because > > > it "overlapped" with pm-qos. So, yes I do consider this just another > > > rename. > > > > It's an extension of an existing framework rather than an addition of a new > > one, with entirely new API and so on. Extending existing APIs is much > > preferred to adding new ones, in general. > > > > Rafael _______________________________________________ linux-pm mailing list linux-pm@xxxxxxxxxxxxxxxxxxxxxxxxxx https://lists.linux-foundation.org/mailman/listinfo/linux-pm
