Re: [RFC][PATCH 4/4] futex: Rewrite FUTEX_UNLOCK_PI
From: Sebastian Andrzej Siewior
Date: Wed Oct 05 2016 - 04:21:17 EST
On 2016-10-05 10:09:12 [+0200], Peter Zijlstra wrote:
> On Wed, Oct 05, 2016 at 09:41:47AM +0200, Sebastian Andrzej Siewior wrote:
> > are those problems DL related?
> One of them, the other is that PI thing you did that ugly nodeboost
> thing for, right?
this no-de-boost yes. This is probably a problem since we have this
"delayed" wake-up. I've been thinking about a marked in PI state to
ignore a de-boost so the spin_unlock() won't be a problem. But if I
understand it right, then this won't solve the DL problem since you
can't have two tasks at the same priority.