Date: Thu, 21 Jun 2012 14:32:35 -0700
From: Tejun Heo <tj@kernel.org>
To: Josh Hunt <joshhunt00@gmail.com>
Cc: Vivek Goyal <vgoyal@redhat.com>, Jens Axboe <axboe@kernel.dk>,
        linux-kernel@vger.kernel.org, rni@google.com
Subject: Re: multi-second application stall in open()
Message-ID: <20120621213235.GF4642@google.com>
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Hello,

On Thu, Jun 21, 2012 at 04:28:24PM -0500, Josh Hunt wrote:
> When you say the code has diverged from upstream, do you mean from 3.0
> to 3.5?

It's based on something diverged from 2.6.X, so an ancient thing.

> Or maybe I'm misunderstanding what you're getting at. Also, if
> you have any links to the watchdog timer code you're referring to I
> would appreciate it.

Rakesh is the one who observed the bug and wrote the watchdog code.
Rakesh, I think Josh is seeing similar cfqq hang issue.  Did the
watchdog code reveal why that happened?  Or was it mainly to just kick
the queue and keep it going?

Thanks.

-- 
tejun
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