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Date: Tue, 13 Sep 2016 23:42:44 +0200
From: Peter Zijlstra <peterz@infradead.org>
To: Byungchul Park <max.byungchul.park@gmail.com>
Cc: Byungchul Park <byungchul.park@lge.com>,
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Subject: Re: [PATCH v3 07/15] lockdep: Implement crossrelease feature
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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.