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Date: Wed, 26 Sep 2012 13:14:17 -0700
Message-ID: <CALCNsJRR_=HqRWUduDk2GPKcnSgaHky4ybTjUa_BXfwcA3W88g@mail.gmail.com>
From: Vijay Singh <vijju.singh@gmail.com>
To: Jack Vogel <jfvogel@gmail.com>
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Cc: freebsd-net@freebsd.org, John Baldwin <jhb@freebsd.org>
Subject: Re: ixgbe rx & tx locks
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> Jack, I am wondering if this could be avoided if we can avoid to
> enqueue the task OR re-enable interrupts if the other one is already
> scheduled. Is this possible?

It seems to me that ixgbe_handle_que() should only be doing
ixgbe_rxeof(). When ever mq_start() is unable to send, it enqueues the
new txq_task. Also, this is checked periodically from the timer
function as well. I will try an experiment to evaluate only more_rx in
ixgbe_msix_que() and change ixgbe_handle_que() to do rx processing
only. I will report back findings.

Meanwhile it its immediately obvious to anyone what this will break,
please let me know.

-vijay