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From: "Xie, Huawei" <huawei.xie@intel.com>
To: "Ouyang, Changchun" <changchun.ouyang@intel.com>, "dev@dpdk.org"
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Thread-Topic: [dpdk-dev] [PATCH v2 02/24] virtio: Use weaker barriers
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Date: Tue, 27 Jan 2015 07:56:36 +0000
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Subject: Re: [dpdk-dev] [PATCH v2 02/24] virtio: Use weaker barriers
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>-------if (likely(nb_enqueued)) {
>------->-------virtio_wmb();
>------->-------if (unlikely(virtqueue_kick_prepare(rxvq))) {
>------->------->-------virtqueue_notify(rxvq);
>------->------->-------PMD_RX_LOG(DEBUG, "Notified\n");
>------->-------}
>-------}
>-------vq_update_avail_idx(rxvq);


Two confuses for the modification here:

1.
why notify host without updating avail idx?
Will this cause potential deadlock?

2.
Why update avail index even no packets are enqueued?