Thanks for the responses, Then what is the advantage of chaining mbuffs over using the mbuff array?
On Thu, Feb 10, 2022 at 2:26 PM Ferruh Yigit <ferruh.yi...@intel.com> wrote: > On 2/9/2022 10:46 PM, Stephen Hemminger wrote: > > On Wed, 9 Feb 2022 22:18:24 +0000 > > Ferruh Yigit <ferruh.yi...@intel.com> wrote: > > > >> On 2/9/2022 6:03 PM, Ansar Kannankattil wrote: > >>> Hi > >>> My intention is to decrease the number of rte_tx_eth_burst calls, I > know that mentioning nb_pkts will result in sending multiple packets in a > single call. > >>> But providing nb_pkts=1 and posting a head mbuff having number of > mbuffs linked with it will results sending multiple packets > >> > >> If driver supports, you can do it. > >> Driver should expose this capability via RTE_ETH_TX_OFFLOAD_MULTI_SEGS > flag, > >> in 'dev_info->tx_offload_capa'. > >> > >>> If not, what is the use case of linking multiple mbuffs together > >> > >> It is also used in Rx path (again if driver supports). > > > > I think Ansar was asking about chaining multiple packets in one call to > tx burst. > > The chaining in DPDK is to make a single packet out of multiple pieces > (like writev). > > > > DPDK mbufs were based on original BSD concept. > > In BSD mbufs, mbuf has two linked lists. > > BSD m->m_next pointer == DPDK m->next for multiple parts of packet. > > BSD m->m_nextpkt for next packet in queue > > > > There is no nextpkt in DPDK. > > Right, chaining mbufs is for segmented packets. >
