From mboxrd@z Thu Jan  1 00:00:00 1970
From: Olivier Matz <olivier.matz@6wind.com>
Subject: Re: [PATCH 2/3] net/virtio: rationalize queue flushing
Date: Thu, 18 Jan 2018 14:55:44 +0100
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 <20180118090733.12728-3-olivier.matz@6wind.com>
 <20180118132609.GG29540@yliu-mob>
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Cc: dev@dpdk.org, Maxime Coquelin <maxime.coquelin@redhat.com>,
 Tiwei Bie <tiwei.bie@intel.com>, stable@dpdk.org
To: Yuanhan Liu <yliu@fridaylinux.org>
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On Thu, Jan 18, 2018 at 09:26:09PM +0800, Yuanhan Liu wrote:
> Hi Oliver,
> 
> On Thu, Jan 18, 2018 at 10:07:32AM +0100, Olivier Matz wrote:
> > Rationalize the function virtio_dev_free_mbufs():
> > 
> > - skip NULL vqs instead of crashing: this is required for the
> >   next commit
> > - use the same kind of loop than in virtio_free_queues()
> > - also flush mbufs from the control queue (this is useless yet)
> 
> Could we just do "nr_vq = virtio_get_nr_vq(hw) - 1" with a comment that
> CQ is excluded, for skipping the CQ?

Is "nr_vq = virtio_get_nr_vq(hw) - 1" always valid?
Shouldn't we do this check?
  if (vtpci_with_feature(hw, VIRTIO_NET_F_CTRL_VQ))

Instead, I suggest this:

		queue_type = virtio_get_queue_type(hw, i);
		if (queue_type == VTNET_RQ)
			type = "rxq";
		else if (queue_type == VTNET_TQ)
			type = "txq";
		else
-			type = "cq";
+			continue;


> > - factorize common code between rxq, txq, cq
> > 
> > Cc: stable@dpdk.org
> 
> Could you split the patch two 2:
> 
> - one for fixing the crash (skip the NULL vqs). We only need this one
>   for stable release.
> - another one for the refactoring

Yes, do you want them all in the same patchset?


Thank you for the comments
Olivier