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Date: Mon, 15 Oct 2012 20:58:28 +0400
From: Gleb Smirnoff <glebius@FreeBSD.org>
To: Jack Vogel <jfvogel@gmail.com>
Subject: Re: ixgbe & if_igb RX ring locking
Message-ID: <20121015165828.GX89655@glebius.int.ru>
References: <5079A9A1.4070403@FreeBSD.org> <20121015162926.GV89655@FreeBSD.org>
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Cc: "Alexander V. Chernikov" <melifaro@FreeBSD.org>, net@FreeBSD.org
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On Mon, Oct 15, 2012 at 09:39:24AM -0700, Jack Vogel wrote:
J> > To me this unlock/lock looks like a legacy from times, when the driver
J> > had a single mutex for both TX and RX parts.
J> >
J> > And removing this re-locking in foo_rxeof() was one of the aims for
J> > separate
J> > TX/RX locking.
J> >
J> > Really, lurking through history shows that once driver had split its
J> > locking
J> > to separate RX and TX part, these unlock/lock was removed. However, later
J> > this unlock/lock was added back:
J> >
J> >
J> > http://svnweb.freebsd.org/base/head/sys/dev/e1000/if_igb.c?revision=209068&view=markup
J> >
J> > , without any comments for the reason it is added back.
J> >
J> > I did not want to add it back, there were problems that constrained me to
J> do so, although its
J> been some time, I'd be happy to do some testing again without and see.

Can you please dig through mail archives to identify these problems? I
can't imagine any.

-- 
Totus tuus, Glebius.