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To: Yuanhan Liu <yuanhan.liu@linux.intel.com>, dev@dpdk.org
References: <1471939839-29778-1-git-send-email-yuanhan.liu@linux.intel.com>
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From: Maxime Coquelin <maxime.coquelin@redhat.com>
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 (mx1.redhat.com [10.5.110.26]); Tue, 23 Aug 2016 12:27:34 +0000 (UTC)
Subject: Re: [dpdk-dev] [PATCH 3/6] vhost: introduce last avail idx for Tx
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On 08/23/2016 10:10 AM, Yuanhan Liu wrote:
> So far, we retrieve both the used ring avail ring idx by last_used_idx
> var; it won't be a problem because we used ring is updated immediately
> after those avail entries are consumed.
>
> But that's not true when Tx zero copy is enabled, that used ring is updated
> only when the mbuf is consumed. Thus, we need use another var to note
> the last avail ring idx we have consumed.
>
> Therefore, last_avail_idx is introduced.
>
> Signed-off-by: Yuanhan Liu <yuanhan.liu@linux.intel.com>
> ---
>  lib/librte_vhost/vhost.h      |  2 +-
>  lib/librte_vhost/virtio_net.c | 19 +++++++++++--------
>  2 files changed, 12 insertions(+), 9 deletions(-)

Looks good to me:
Reviewed-by: Maxime Coquelin <maxime.coquelin@redhat.com>

Thanks,
Maxime