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[Xen-devel] Re: [PATCH] xen/blkback: Don't let in-flight requests defer

To: "Pradeep Vincent" <pradeepv@xxxxxxxxxx>
Subject: [Xen-devel] Re: [PATCH] xen/blkback: Don't let in-flight requests defer pending ones.
From: "Jan Beulich" <JBeulich@xxxxxxxxxx>
Date: Wed, 01 Jun 2011 09:24:15 +0100
Cc: Xen <xen-devel@xxxxxxxxxxxxxxxxxxx>, "konrad.wilk@xxxxxxxxxx" <konrad.wilk@xxxxxxxxxx>, Daniel Stodden <daniel.stodden@xxxxxxxxxx>
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>>> On 01.06.11 at 10:02, "Vincent, Pradeep" <pradeepv@xxxxxxxxxx> wrote:
> Re: Locking
> I was reflecting Jan Beulich's comment earlier in this thread. Like I said
> before (in this thread), the locking logic in blkback isn't obvious from
> the code and the failure modes seem benign. If someone has good context on
> blkback locking strategy, I would love to learn. Also it would be very
> useful to add some comments around lock usage to the blkback code.
> Jan ??

No, not really - I'm more of an observer on this and similar
discussions, just trying to learn as much as I can. Now and then I
do notice possible issues, but as the design and the reasons for
the choices made aren't (afaik, and like you also say) documented,
a lot of room for guessing is usually left.


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