On Tuesday, 3 July 2007 23:14, Benjamin Herrenschmidt wrote: > > > > - For STR, don't do the freezer thing. > > > > In the long run, I agree. > > > > Still, can you please read this post from Alan Stern: > > > > https://lists.linux-foundation.org/pipermail/linux-pm/2007-June/012847.html > > > > ? I don't think I'm able to repeat the arguments given in there in a > > convincing way. > > That's the same crackpot I've been hearing for the past 3 years or > so ... > > Both Paulus and I think the freezer is just a way to try to put your > head in the sand and ignore the problem. It causes as many problems as > it solves on its own, and is just not a solution that will be of any use > once you start implementing dynamic PM schemes etc... > > In many cases, having proper support for "live" suspend of devices is > just a matter of having a couple of helpers in whatever subsystem those > drivers hookup with. In the case of network, for example, it's mostly > trivial (stop the queue). For block, it's not terribly hard neither, > though you want to have some orderign/atomicity between the blocking of > the incoming request queue and the sending of things like spindown & > flush commands to the disk. For old-style IDE, that was fairly easily > solved by piping suspend/resume command down the request queue itself > and have the queue block/unblbock itself after processing them. Some of > that logic could maybe be moved to the block layer for all block drivers > to benefit. > > But yes, overall, there is work to do on drivers and I'm doing the ones > I hit on the platforms I use. I don't think the freezer is any kind of > remotely good solution, just a way to continue avoiding the problem. Still, do you really think that we're ready to drop it _right_ _now_ (I'm referring to suspend only) and if so than on what basis (except that you don't like it, which falls short of being a techical argument)? Greetings, Rafael -- "Premature optimization is the root of all evil." - Donald Knuth _______________________________________________ linux-pm mailing list linux-pm@xxxxxxxxxxxxxxxxxxxxxxxxxx https://lists.linux-foundation.org/mailman/listinfo/linux-pm
