> -----Original Message----- > From: Shaw, Jeffrey B > Sent: Thursday, February 12, 2015 1:29 AM > To: Chen, Jing D > Cc: dev at dpdk.org; Zhang, Helin; Qiu, Michael; nhorman at tuxdriver.com; > thomas.monjalon at 6wind.com; david.marchand at 6wind.com > Subject: Re: [PATCH v4 10/15] fm10k: add receive and tranmit function > > On Wed, Feb 11, 2015 at 09:31:33AM +0800, Chen Jing D(Mark) wrote: > > > +uint16_t > > +fm10k_recv_pkts(void *rx_queue, struct rte_mbuf **rx_pkts, > > + uint16_t nb_pkts) > > +{ > > + struct rte_mbuf *mbuf; > > + union fm10k_rx_desc desc; > > + struct fm10k_rx_queue *q = rx_queue; > > + uint16_t count = 0; > > + int alloc = 0; > > + uint16_t next_dd; > > + > > + next_dd = q->next_dd; > > + > > + nb_pkts = RTE_MIN(nb_pkts, q->alloc_thresh); > > + for (count = 0; count < nb_pkts; ++count) { > > + mbuf = q->sw_ring[next_dd]; > > + desc = q->hw_ring[next_dd]; > > + if (!(desc.d.staterr & FM10K_RXD_STATUS_DD)) > > + break; > > +#ifdef RTE_LIBRTE_FM10K_DEBUG_RX > > + dump_rxd(&desc); > > +#endif > > + rte_pktmbuf_pkt_len(mbuf) = desc.w.length; > > + rte_pktmbuf_data_len(mbuf) = desc.w.length; > > + > > + mbuf->ol_flags = 0; > > +#ifdef RTE_LIBRTE_FM10K_RX_OLFLAGS_ENABLE > > + rx_desc_to_ol_flags(mbuf, &desc); > > +#endif > > + > > + mbuf->hash.rss = desc.d.rss; > > + > > + rx_pkts[count] = mbuf; > > + if (++next_dd == q->nb_desc) { > > + next_dd = 0; > > + alloc = 1; > > + } > > + > > + /* Prefetch next mbuf while processing current one. */ > > + rte_prefetch0(q->sw_ring[next_dd]); > > + > > + /* > > + * When next RX descriptor is on a cache-line boundary, > > + * prefetch the next 4 RX descriptors and the next 8 pointers > > + * to mbufs. > > + */ > > + if ((next_dd & 0x3) == 0) { > > + rte_prefetch0(&q->hw_ring[next_dd]); > > + rte_prefetch0(&q->sw_ring[next_dd]); > > + } > > + } > > + > > + q->next_dd = next_dd; > > + > > + if ((q->next_dd > q->next_trigger) || (alloc == 1)) { > > + rte_mempool_get_bulk(q->mp, (void **)&q->sw_ring[q- > >next_alloc], > > + q->alloc_thresh); > > The return value should be checked here in case the mempool runs out > of buffers. Thanks Helin for spotting this. I'm not sure how I missed it > originally.
Thanks! I'll change accordingly. > > > + for (; q->next_alloc <= q->next_trigger; ++q->next_alloc) { > > + mbuf = q->sw_ring[q->next_alloc]; > > + > > + /* setup static mbuf fields */ > > + fm10k_pktmbuf_reset(mbuf, q->port_id); > > + > > + /* write descriptor */ > > + desc.q.pkt_addr = > MBUF_DMA_ADDR_DEFAULT(mbuf); > > + desc.q.hdr_addr = > MBUF_DMA_ADDR_DEFAULT(mbuf); > > + q->hw_ring[q->next_alloc] = desc; > > + } > > + FM10K_PCI_REG_WRITE(q->tail_ptr, q->next_trigger); > > + q->next_trigger += q->alloc_thresh; > > + if (q->next_trigger >= q->nb_desc) { > > + q->next_trigger = q->alloc_thresh - 1; > > + q->next_alloc = 0; > > + } > > + } > > + > > + return count; > > +} > > + > > Thanks, > Jeff