On Fri, 2014-06-27 at 10:01 -0400, Steven Rostedt wrote: > This seems like a lot of hacks. It is exactly that, lacking proper pooper-scooper, show rt kernel how to not step in it. > I'm wondering if it would work if we > just have the rt_spin_lock_slowlock not call schedule(), but call > __schedule() directly. I mean it would keep with the mainline paradigm > as spinlocks don't sleep there, and one going to sleep in the -rt > kernel is similar to it being preempted by a very long NMI. Problem being that we do sleep there, do need wakeup. I have a hack that turns them back into spinning locks, but it.. works too :) > Does a spin_lock going to sleep really need to do all the presched and > postsched work? It would be lovely if we didn't have to do any of that. On the IO bit, I haven't seen hard evidence that the spinlock bit is absolutely required (better not be, it doesn't guarantee anything), but the combined hack did kill IO deadlock of multiple filesystems. -Mike -- To unsubscribe from this list: send the line "unsubscribe linux-rt-users" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
