Re: [dpdk-dev] [PATCH v3] net/ixgbe: include QPRDC in imissed stat

["Zhao1, Wei" <wei.zhao1@intel.com>]

Hi, Harris, Cody

  I have reply in other mail for " why imissed doesn't include it ", thanks.

> -----Original Message-----
> From: Harris, Cody <codh@amazon.com>
> Sent: Thursday, May 28, 2020 4:17 PM
> To: Zhao1, Wei <wei.zhao1@intel.com>; dev@dpdk.org
> Cc: Ye, Xiaolong <xiaolong.ye@intel.com>; Guo, Jia <jia.guo@intel.com>
> Subject: Re: [dpdk-dev] [PATCH v3] net/ixgbe: include QPRDC in imissed stat
> 
> Hi Zhao Wei,
> 
> I understand that the QPRDC drop count is available by stats->q_errors. I'm
> interested to know why imissed doesn't include it. The name imissed makes it
> sound like the counter counts incoming missed (valid) packets regardless of
> where the drop occurs during reception.
> 
> I think the name imissed is misleading if it doesn't include all types of dropped
> valid packets, so I made this CR to see how receptive the DPDK maintainers
> would be to include all dropped packet counts.
> 
> Thanks for your review,
> 
> ~Cody
> 
> On 5/28/20, 1:10 AM, "Zhao1, Wei" <wei.zhao1@intel.com> wrote:
> 
>     CAUTION: This email originated from outside of the organization. Do not
> click links or open attachments unless you can confirm the sender and know the
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> 
> 
> 
>     Hi, Cody Harris
> 
>       More info, you can get the number of dropped packet per queue by
> stats->q_errors,
>     No need to add this into imissed.
> 
>     > -----Original Message-----
>     > From: Zhao1, Wei
>     > Sent: Thursday, May 28, 2020 11:54 AM
>     > To: Cody Harris <codh@amazon.com>; dev@dpdk.org
>     > Subject: RE: [dpdk-dev] [PATCH v3] net/ixgbe: include QPRDC in imissed
> stat
>     >
>     > HI，Cody Harris
>     >
>     > > -----Original Message-----
>     > > From: dev <dev-bounces@dpdk.org> On Behalf Of Cody Harris
>     > > Sent: Tuesday, May 19, 2020 1:08 PM
>     > > To: dev@dpdk.org
>     > > Cc: Cody Harris <codh@amazon.com>
>     > > Subject: [dpdk-dev] [PATCH v3] net/ixgbe: include QPRDC in imissed
>     > > stat
>     > >
>     > > The ixgbe imissed statstic originally only contained dropped packets
>     > > counted by the RXMPC registers. This change includes additional types
>     > > of packet drops counted by the QPRDC registers.
>     > >
>     > > Intel support confimed that the packet drops counted by the QPRDC
>     > > registers do not double-count drops counted by RXMPC registers:
>     > >
>     > > "RXMPC counts packets that are dropped because there is no room in
> the
>     > > internal packet buffer.  QPRDC counts packets that are dropped
> because
>     > > they can't be transferred to system memory. These packets have been
>     > > stored in the internal packet buffer, so there should be no overlap with
>     > RXMPC."
>     > >
>     > > Signed-off-by: Cody Harris <codh@amazon.com>
>     > > ---
>     > >  drivers/net/ixgbe/ixgbe_ethdev.c | 2 +-
>     > >  1 file changed, 1 insertion(+), 1 deletion(-)
>     > >
>     > > diff --git a/drivers/net/ixgbe/ixgbe_ethdev.c
>     > > b/drivers/net/ixgbe/ixgbe_ethdev.c
>     > > index a4e5c539d..7284ca28e 100644
>     > > --- a/drivers/net/ixgbe/ixgbe_ethdev.c
>     > > +++ b/drivers/net/ixgbe/ixgbe_ethdev.c
>     > > @@ -3366,7 +3366,7 @@ ixgbe_dev_stats_get(struct rte_eth_dev
> *dev,
>     > > struct rte_eth_stats *stats)
>     > >     }
>     > >
>     > >     /* Rx Errors */
>     > > -   stats->imissed  = total_missed_rx;
>     > > +   stats->imissed  = total_missed_rx + total_qprdc;
>     >
>     > If Rx queue is disabled in the RXDCTL register, packet direct to this
> queue is
>     > also dropped and count by this Register QPRDC, but the definition of
> imissed is
>     > "Total of RX packets dropped by the HW because there are no available
> buffer"
>     > in rte layer.
>     > So, it maybe mislead users if we mix the 2 statistic, is that so?
>     > Also, x550 has other definition for this register, we can not mix them.
>     >
>     >
>     > >     stats->ierrors  = hw_stats->crcerrs +
>     > >                       hw_stats->mspdc +
>     > >                       hw_stats->rlec +
>     > > --
>     > > 2.24.1.AMZN
> 
>