RTE_PKTMBUF_HEADROOM defines the headroom this would be true only if the buff_start was aligned to 512 which is not.
On Tue, Oct 7, 2014 at 1:05 PM, Ananyev, Konstantin < konstantin.ananyev at intel.com> wrote: > > > > -----Original Message----- > > From: dev [mailto:dev-bounces at dpdk.org] On Behalf Of Alex Markuze > > Sent: Tuesday, October 07, 2014 10:40 AM > > To: dev at dpdk.org > > Subject: [dpdk-dev] Aligned RX data. > > > > Hi , I'm trying to receive aligned packets from the wire. > > Meaning that for all received packets the pkt.data is always aligned to > > (512 -H). > > > > Looking at the pmds of ixgbe/vmxnet I see that the pmds call > > __rte_mbuf_raw_alloc and set the rx descriptor with a > > RTE_MBUF_DATA_DMA_ADDR_DEFAULT > > Instead of the more appropriate RTE_MBUF_DATA_DMA_ADDR. > > > > Do I need to modify each pmd I'm using to be able to receive aligned > data? > > Make sure that your all your mbufs are aligned by 512 and set in your > config RTE_PKTMBUF_HEADROOM=512-H? > > > > Or have I missed something? > > > > Thanks >
