Re: [PATCH v3 07/15] lockdep: Implement crossrelease feature

From: Peter Zijlstra
Date: Tue Sep 13 2016 - 17:43:06 EST


On Tue, Sep 13, 2016 at 09:38:29PM +0200, Peter Zijlstra wrote:

> > > I _think_ you propose to keep track of all prior held locks and then use
> > > the union of the held list on the block-chain with the prior held list
> > > from the complete context.
> >
> > Almost right. Only thing we need to do to consider the union is to
> > connect two chains of two contexts by adding one dependency 'b -> a'.
>
> Sure, but how do you arrive at which connection to make. The document is
> entirely silent on this crucial point.
>
> The union between the held-locks of the blocked and prev-held-locks of
> the release should give a fair indication I think, but then, I've not
> thought too hard on this yet.

s/union/intersection/

those that are in both sets.