> -----Original Message-----
> From: dev [mailto:dev-bounces at dpdk.org] On Behalf Of stephen at
> networkplumber.org
> Sent: Friday, January 23, 2015 6:24 AM
> To: dev at dpdk.org
> Cc: Stephen Hemminger
> Subject: [dpdk-dev] [PATCH] ixgbe: do not include CRC in Tx byte count
>
> From: Stephen Hemminger <shemming at brocade.com>
>
> The ixgbe driver was including CRC in the transmit packet byte
> count, but not for packets received.
> This was notice when forwarding and
> the number of bytes received was greater than the number of bytes transmitted
> for the same number of packets. Make the driver behave like other
> virtual devices and not include CRC in byte count. Use the same queue
> counters already computed and used for Rx.
About RX side stats - as I remember it depends to what value hw_stip_crc is set
at configure().
If hw_stip_crc==1, then, yes CRC bytes are not included into QBRC value.
I If hw_stip_crc==0, then CRC bytes are included into QBRC.
I.E:
./dpdk.org/x86_64-native-linuxapp-gcc/app/testpmd -c ff -n 4 -w 86:00.1 -- -i
--tx-queue-stats-mapping='(0,0,0)' --rx-queue-stats-mapping='(0,0,0)'
--crc-strip
testpmd> start
testpmd> show port stats all
######################## NIC statistics for port 0 ########################
RX-packets: 1 RX-errors: 0 RX-bytes:
60 // sum of QBRC[]
RX-badcrc: 0 RX-badlen: 0 RX-errors:
0
RX-nombuf: 0
TX-packets: 1 TX-errors: 0 TX-bytes:
64 //GOTC
Stats reg 0 RX-packets: 1 RX-errors: 0 RX-bytes:
60 //QBRC[0]
...
Stats reg 0 TX-packets: 1 TX-bytes:
60 // QBTC[0]
############################################################################
./dpdk.org/x86_64-native-linuxapp-gcc/app/testpmd -c ff -n 4 -w 86:00.1 -- -i
--tx-queue-stats-mapping='(0,0,0)' --rx-queue-stats-mapping='(0,0,0)'
testpmd> start
testpmd> show port stats all
######################## NIC statistics for port 0 ########################
RX-packets: 1 RX-errors: 0 RX-bytes:
64 // sum of QBRC[]
RX-badcrc: 0 RX-badlen: 0 RX-errors:
0
RX-nombuf: 0
TX-packets: 1 TX-errors: 0 TX-bytes:
64 //GOTC
Stats reg 0 RX-packets: 1 RX-errors: 0 RX-bytes:
64 //QBRC[0]
....
Stats reg 0 TX-packets: 1 TX-bytes:
60 // QBTC[0]
############################################################################
So now, number of RX/TX stat bytes for simple forwarding are equal when
hw_stip_crc==0 and
differ when hw_stip_crc==1,
With your change, as I understand, it would be visa-versa.
I don' t mind changing it yours way, but wonder why that is any better?
Probably the proper patch, should also do something like that:
stats->ibytes = total_qbrc - stats->ipackets * dev->data->dev_conf.
hw_strip_crc * CRC_LEN;
too?
About using sum of QBRC[] for stats.ibytes instead of GORC, I think the initial
reason was:
http://www.intel.com/content/www/us/en/ethernet-controllers/82599-10-gbe-controller-spec-update.html:
7 GPRC and GORCL/H Also Count Missed Packets
Problem:
GPRC (Good Packets Received Count) and GORCL/H (Good Octets Received Count)
count missed
packets and missed packets bytes; this is not consistent with previous products.
Implication:
None.
331521-002 23
Errata-Intel(r) 82599 10 GbE Controller
Workaround:
Statistics are available indirectly for these registers. This workaround is
included in Intel drivers.
* For GPRC - Subtract MPC (Missed Packet Count) from GPRC. Alternatively, use
QPRC.
* For GORCL/H - use QBRCL/H (Quad Bytes Received).
Konstantin
>
> Signed-off-by: Stephen Hemminger <stephen at networkplumber.org>
> ---
> lib/librte_pmd_ixgbe/ixgbe_ethdev.c | 11 ++++++++---
> 1 file changed, 8 insertions(+), 3 deletions(-)
>
> diff --git a/lib/librte_pmd_ixgbe/ixgbe_ethdev.c
> b/lib/librte_pmd_ixgbe/ixgbe_ethdev.c
> index b58ec45..27355eb 100644
> --- a/lib/librte_pmd_ixgbe/ixgbe_ethdev.c
> +++ b/lib/librte_pmd_ixgbe/ixgbe_ethdev.c
> @@ -1724,12 +1724,15 @@ ixgbe_dev_stats_get(struct rte_eth_dev *dev, struct
> rte_eth_stats *stats)
> struct ixgbe_hw_stats *hw_stats =
> IXGBE_DEV_PRIVATE_TO_STATS(dev->data->dev_private);
> uint32_t bprc, lxon, lxoff, total;
> - uint64_t total_missed_rx, total_qbrc, total_qprc;
> + uint64_t total_missed_rx;
> + uint64_t total_qbrc, total_qprc, total_qbtc, total_qptc;
> unsigned i;
>
> total_missed_rx = 0;
> total_qbrc = 0;
> total_qprc = 0;
> + total_qbtc = 0;
> + total_qptc = 0;
>
> hw_stats->crcerrs += IXGBE_READ_REG(hw, IXGBE_CRCERRS);
> hw_stats->illerrc += IXGBE_READ_REG(hw, IXGBE_ILLERRC);
> @@ -1770,6 +1773,8 @@ ixgbe_dev_stats_get(struct rte_eth_dev *dev, struct
> rte_eth_stats *stats)
>
> total_qprc += hw_stats->qprc[i];
> total_qbrc += hw_stats->qbrc[i];
> + total_qptc += hw_stats->qptc[i];
> + total_qbtc += hw_stats->qbtc[i];
> }
> hw_stats->mlfc += IXGBE_READ_REG(hw, IXGBE_MLFC);
> hw_stats->mrfc += IXGBE_READ_REG(hw, IXGBE_MRFC);
> @@ -1860,8 +1865,8 @@ ixgbe_dev_stats_get(struct rte_eth_dev *dev, struct
> rte_eth_stats *stats)
> /* Fill out the rte_eth_stats statistics structure */
> stats->ipackets = total_qprc;
> stats->ibytes = total_qbrc;
> - stats->opackets = hw_stats->gptc;
> - stats->obytes = hw_stats->gotc;
> + stats->opackets = total_qptc;
> + stats->obytes = total_qbtc;
> stats->imcasts = hw_stats->mprc;
>
> for (i = 0; i < IXGBE_QUEUE_STAT_COUNTERS; i++) {
> --
> 2.1.4
