Re: [dpdk-dev] [PATCH] virtio: Fix stats issue

["Ouyang, Changchun" <changchun.ouyang@intel.com>]

On 3/23/2015 3:20 PM, David Marchand wrote:
> Hello,
>
> Hello,
>
> On Mon, Mar 23, 2015 at 7:56 AM, Ouyang Changchun 
> <changchun.ouyang@intel.com <mailto:changchun.ouyang@intel.com>> wrote:
>
>     It need clear/reset the stats information before count in all
>     queues data.
>
>     Signed-off-by: Changchun Ouyang <changchun.ouyang@intel.com
>     <mailto:changchun.ouyang@intel.com>>
>     ---
>      lib/librte_pmd_virtio/virtio_ethdev.c | 8 ++++++++
>      1 file changed, 8 insertions(+)
>
>     diff --git a/lib/librte_pmd_virtio/virtio_ethdev.c
>     b/lib/librte_pmd_virtio/virtio_ethdev.c
>     index 603be2d..e4cb55e 100644
>     --- a/lib/librte_pmd_virtio/virtio_ethdev.c
>     +++ b/lib/librte_pmd_virtio/virtio_ethdev.c
>     @@ -572,6 +572,10 @@ virtio_dev_stats_get(struct rte_eth_dev *dev,
>     struct rte_eth_stats *stats)
>      {
>             unsigned i;
>
>     +       stats->opackets = 0;
>     +       stats->obytes = 0;
>     +       stats->oerrors = 0;
>
>
> stats are supposed to be zero'd in generic rte_ethdev.c before this 
> pmd function is called, so this patch seems useless to me.
> Can you give some context ?
>
> Same comment for the i* part.
>
2 reasons:
1. this change could keep the stats_get has consistent behavior with the 
one in other drivers;
2. we don't rely on the assumption of caller always zero'd the stats, 
and still can return correct value;
thanks
Changchun