Date: Fri, 18 May 2012 11:02:47 +0100
From: Alan Cox <alan@lxorguk.ukuu.org.uk>
To: Kent Overstreet <koverstreet@google.com>
Cc: Tejun Heo <tj@kernel.org>, linux-bcache@vger.kernel.org,
        linux-kernel@vger.kernel.org, dm-devel@redhat.com, agk@redhat.com
Subject: Re: [Bcache v13 07/16] Closures
Message-ID: <20120518110247.08696cec@pyramind.ukuu.org.uk>
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> Well, I can definitely understand your reservations about the code; it's
> strange and foreign and complicated. But having beaten my head against
> the various problems and difficulties inherent in asynchronous
> programming for years - well, having found a way to make it sane to me
> it'd be madness to go back.

I think its more of a different paradigm than complicated. The big
question I'd have to ask is how does it fit with hard real time. That is
a big issue given the gradual merging and getting of "hard" real time
into the kernel proper.

In some ways it's not that strange either. A look at what happens on some
of our kref handling in drivers is very similar but hardcoded.

Is the handling of priority inversion within closures a well understood
and solved problem ?

Alan
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