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Date: Wed, 23 Aug 2017 15:03:32 +0900
From: Byungchul Park <byungchul.park@lge.com>
To: Peter Zijlstra <peterz@infradead.org>
Cc: Dave Chinner <david@fromorbit.com>, mingo@kernel.org,
        linux-kernel@vger.kernel.org, kernel-team@lge.com,
        Arnaldo Carvalho de Melo <acme@kernel.org>, Tejun Heo <tj@kernel.org>,
        Boqun Feng <boqun.feng@gmail.com>
Subject: Re: [PATCH v3 1/3] lockdep: Make LOCKDEP_CROSSRELEASE configs all
 part of PROVE_LOCKING
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On Wed, Aug 23, 2017 at 11:12:17AM +0900, Byungchul Park wrote:
> > > We have to detect dependecies if it exists, even in the following case:
> > > 
> > > oooooooiiiiiiiiiiiiiiiiiii.........
> > >   |<- range for commit ->|
> > > 
> > >   where
> > >   o: acquisition outside of each work,
> > >   i: acquisition inside of each work,
> > > 
> > > With yours, we can never detect dependecies wrt 'o'.
> > 
> > There really shouldn't be any o's when you call
> 
> There can be any o's.

I meant it's very possible for 'o's to exist. And we have to, of course,
consider them wrt dependencies. No reason we should ignore them.

> > crossrelease_hist_start(XHLOCK_PROC), it should denote the bottom of a

Honestly, I prefer another naming like XHLOCK_WORK or XHLOCK_SYSCALL over
XHLOCK_PROC, since the functions are for special contexts e.g. works.
But I thought XHLOCK_PROC is not bad because XHLOCK_WORK and
XHLOCK_SYSCALL does never conflict to each other and they anyway run as
normal process contexts.

Remind they are for special contexts.