From mboxrd@z Thu Jan  1 00:00:00 1970
From: Jesse Brandeburg <jesse.brandeburg@intel.com>
Subject: Re: [net 1/3] i40e: fix un-necessary Tx hangs
Date: Tue, 6 Jan 2015 09:04:40 -0800
Message-ID: <20150106090440.00006a7d@unknown>
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Cc: <netdev@vger.kernel.org>, <nhorman@redhat.com>,
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To: Jeff Kirsher <jeffrey.t.kirsher@intel.com>, <davem@davemloft.net>
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On Tue, 6 Jan 2015 00:44:22 -0800
Jeff Kirsher <jeffrey.t.kirsher@intel.com> wrote:

> From: Jesse Brandeburg <jesse.brandeburg@intel.com>
> 
> When the driver was polling with interrupts disabled the hardware
> will occasionally not write back descriptors.  This patch causes
> the driver to detect this situation and force an interrupt to
> fire which will flush the stuck descriptor.  Does not conflict
> with NAPI because if we are already polling the napi_schedule is
> ignored.  Additionally the extra interrupts are rate limited, so
> don't cause a burden to the CPU.

Dave, sorry to do this but we discovered a bug in this patch (where
this patch impacts performance) and didn't interrupt Jeff before he sent
it (my mistake) I will prep a v2 for Jeff.

Please do not apply.