On 07/31/2016 10:46 AM, Vlad Zolotarov wrote: > > > On 07/20/2016 05:24 PM, Tomasz Kulasek wrote: >> This is an ABI deprecation notice for DPDK 16.11 in librte_ether about >> changes in rte_eth_dev and rte_eth_desc_lim structures. >> >> In 16.11, we plan to introduce rte_eth_tx_prep() function to do >> necessary preparations of packet burst to be safely transmitted on >> device for desired HW offloads (set/reset checksum field according to >> the hardware requirements) and check HW constraints (number of segments >> per packet, etc). >> >> While the limitations and requirements may differ for devices, it >> requires to extend rte_eth_dev structure with new function pointer >> "tx_pkt_prep" which can be implemented in the driver to prepare and >> verify packets, in devices specific way, before burst, what should to >> prevent application to send malformed packets. >> >> Also new fields will be introduced in rte_eth_desc_lim: nb_seg_max and >> nb_mtu_seg_max, providing an information about max segments in TSO and >> non TSO packets acceptable by device. >> >> Signed-off-by: Tomasz Kulasek <tomaszx.kulasek at intel.com> > > Acked-by: Vlad Zolotarov <vladz at scylladb.com>
One small comment however. Although this function is a must we need a way to clearly understand which one the clusters are malformed since dropping the whole bulk is usually not an option and sending the malformed packets anyway may cause a HW hang, thus not an option as well. Another thing - I've pulled the current master and I couldn't find the way an application may query the mentioned Tx offload HW limitation, e.g. maximum number of segments. Knowing this limitation would avoid extra liniarization. thanks, vlad > >> --- >> doc/guides/rel_notes/deprecation.rst | 7 +++++++ >> 1 file changed, 7 insertions(+) >> >> diff --git a/doc/guides/rel_notes/deprecation.rst >> b/doc/guides/rel_notes/deprecation.rst >> index f502f86..485aacb 100644 >> --- a/doc/guides/rel_notes/deprecation.rst >> +++ b/doc/guides/rel_notes/deprecation.rst >> @@ -41,3 +41,10 @@ Deprecation Notices >> * The mempool functions for single/multi producer/consumer are >> deprecated and >> will be removed in 16.11. >> It is replaced by rte_mempool_generic_get/put functions. >> + >> +* In 16.11 ABI changes are plained: the ``rte_eth_dev`` structure >> will be >> + extended with new function pointer ``tx_pkt_prep`` allowing >> verification >> + and processing of packet burst to meet HW specific requirements >> before >> + transmit. Also new fields will be added to the >> ``rte_eth_desc_lim`` structure: >> + ``nb_seg_max`` and ``nb_mtu_seg_max`` provideing information about >> number of >> + segments limit to be transmitted by device for TSO/non-TSO packets. >
