On Tue, 2015-07-28 at 22:45 +0200, Peter Zijlstra wrote: > Also, this code seems to use plist, which means it won't do the right > thing for SCHED_DEADLINE either. Ick, I don't look forward to seeing nice futex plists converted into rbtrees. As opposed to, eg. rtmutexes, there are a few caveats: - Dealing with the top_waiter in rtmutexes is always easy, but in futexes we need to deal with keys, so caching the leftmost won't work as nicely. - This will bloat things like futex_wake, where O(logN) is not suited for FIFO iteration. And iterating linked lists is, in essence, all that we really do when calling futex(2). I have to wonder about the extra overhead added by these points. I do understand the dl concern, nonetheless. -- To unsubscribe from this list: send the line "unsubscribe linux-api" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
