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Date:   Fri, 4 Mar 2022 12:20:02 +0900
From:   Byungchul Park <byungchul.park@lge.com>
To:     Theodore Ts'o <tytso@mit.edu>
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Subject: Re: Report 2 in ext4 and journal based on v5.17-rc1
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On Thu, Mar 03, 2022 at 09:36:25AM -0500, Theodore Ts'o wrote:
> On Thu, Mar 03, 2022 at 02:23:33PM +0900, Byungchul Park wrote:
> > I totally agree with you. *They aren't really locks but it's just waits
> > and wakeups.* That's exactly why I decided to develop Dept. Dept is not
> > interested in locks unlike Lockdep, but fouces on waits and wakeup
> > sources itself. I think you get Dept wrong a lot. Please ask me more if
> > you have things you doubt about Dept.
> 
> So the question is this --- do you now understand why, even though
> there is a circular dependency, nothing gets stalled in the
> interactions between the two wait channels?

I found a point that the two wait channels don't lead a deadlock in
some cases thanks to Jan Kara. I will fix it so that Dept won't
complain it.

Thanks,
Byungchul

> 
> 						- Ted