On Monday, 23 July 2007 14:14, Miklos Szeredi wrote: > > On Monday, 23 July 2007 12:24, Miklos Szeredi wrote: > > > > > The only thing to do is what Rafael has been working on: unfreeze > > > > > things, hope the tasks sort themselves out, and try again. > > > > > > > > That's what I'm questioning. Is there a more reliable way and we've > > > > just given up too quickly? > > > > > > There obviously _are_ more reliable ways. A trivial one seems to be > > > to just not require user tasks to finish syscalls. > > > > > > Yeah, stopping user processes outside the kernel is convenient, but > > > there's no fundamental reason why it is the only place where those > > > tasks can be stopped. > > > > The reason is that we want them to "park" in safe places, ie. where there > > are no locks held etc. Thus, these safe places need to be chosen somehow > > and since they are not marked throughout the code, we choose the obvious > > one. :-) > > Why shouldn't locks be held? > > No locks which are required for suspend must be held, sure. But > otherwise holding locks doesn't matter at all. > > And I'm not saying that is trivial to do, but it might not be too hard > either. > > Rafael, can you please tell, what happened to that patch, that did not > wait for tasks in uninterruptible sleep to be frozen? > > That seemed like a magnificent approach compared to anything that has > been proposed since. Well, the freezer have failed to freeze tasks for a couple of times in my test setup and I've had a couple of hangs. I have an idea how to improve it, but that still requires some pending freezer patches to go first. 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
