Best Regards,
Sun, Chenmin
> -----Original Message-----
> From: Wu, Jingjing <jingjing...@intel.com>
> Sent: Thursday, July 16, 2020 9:57 PM
> To: Sun, Chenmin <chenmin....@intel.com>; Zhang, Qi Z
> <qi.z.zh...@intel.com>; Xing, Beilei <beilei.x...@intel.com>; Wang, Haiyue
> <haiyue.w...@intel.com>
> Cc: dev@dpdk.org
> Subject: RE: [PATCH V4 4/4] net/i40e: FDIR update rate optimization
>
>
> [...]
>
> > +static inline unsigned char *
> > +i40e_find_available_buffer(struct rte_eth_dev *dev) {
> > + struct i40e_pf *pf = I40E_DEV_PRIVATE_TO_PF(dev->data-
> >dev_private);
> > + struct i40e_fdir_info *fdir_info = &pf->fdir;
> > + struct i40e_tx_queue *txq = pf->fdir.txq;
> > + volatile struct i40e_tx_desc *txdp = &txq->tx_ring[txq->tx_tail + 1];
> > + uint32_t i;
> > +
> > + /* no available buffer
> > + * search for more available buffers from the current
> > + * descriptor, until an unavailable one
> > + */
> > + if (fdir_info->txq_available_buf_count <= 0) {
> > + uint16_t tmp_tail;
> > + volatile struct i40e_tx_desc *tmp_txdp;
> > +
> > + tmp_tail = txq->tx_tail;
> > + tmp_txdp = &txq->tx_ring[tmp_tail + 1];
> > +
> > + do {
> > + if ((tmp_txdp->cmd_type_offset_bsz &
> > +
> > rte_cpu_to_le_64(I40E_TXD_QW1_DTYPE_MASK)) ==
> > +
> > rte_cpu_to_le_64(I40E_TX_DESC_DTYPE_DESC_DONE))
> > + fdir_info->txq_available_buf_count++;
> > + else
> > + break;
> > +
> > + tmp_tail += 2;
> > + if (tmp_tail >= txq->nb_tx_desc)
> > + tmp_tail = 0;
> > + } while (tmp_tail != txq->tx_tail);
> > + }
> > +
> > + /*
> > + * if txq_available_buf_count > 0, just use the next one is ok,
> > + * else wait for the next DD until it's set to make sure the data
> > + * had been fetched by hardware
> > + */
> > + if (fdir_info->txq_available_buf_count > 0) {
> > + fdir_info->txq_available_buf_count--;
> > + } else {
> > + /* wait until the tx descriptor is ready */
> > + for (i = 0; i < I40E_FDIR_MAX_WAIT_US; i++) {
> > + if ((txdp->cmd_type_offset_bsz &
> > +
> > rte_cpu_to_le_64(I40E_TXD_QW1_DTYPE_MASK)) ==
> > +
> > rte_cpu_to_le_64(I40E_TX_DESC_DTYPE_DESC_DONE))
> > + break;
> > + rte_delay_us(1);
> > + }
> > + if (i >= I40E_FDIR_MAX_WAIT_US) {
> > + PMD_DRV_LOG(ERR,
> > + "Failed to program FDIR filter: time out to get DD
> > on
> tx
> > queue.");
> > + return NULL;
> > + }
> > + }
> Why wait for I40E_FDIR_MAX_WAIT_US but not return NULL immediately?
Done
> [...]
>
>
> > i40e_flow_fdir_filter_programming(struct i40e_pf *pf,
> > enum i40e_filter_pctype pctype,
> > const struct i40e_fdir_filter_conf *filter,
> > - bool add)
> > + bool add, bool wait_status)
> > {
> > struct i40e_tx_queue *txq = pf->fdir.txq;
> > struct i40e_rx_queue *rxq = pf->fdir.rxq; @@ -2011,8 +2092,10 @@
> > i40e_flow_fdir_filter_programming(struct i40e_pf *pf,
> > volatile struct i40e_tx_desc *txdp;
> > volatile struct i40e_filter_program_desc *fdirdp;
> > uint32_t td_cmd;
> > - uint16_t vsi_id, i;
> > + uint16_t vsi_id;
> > uint8_t dest;
> > + uint32_t i;
> > + uint8_t retry_count = 0;
> >
> > PMD_DRV_LOG(INFO, "filling filter programming descriptor.");
> > fdirdp = (volatile struct i40e_filter_program_desc *) @@ -2087,7
> > +2170,8 @@ i40e_flow_fdir_filter_programming(struct i40e_pf *pf,
> >
> > PMD_DRV_LOG(INFO, "filling transmit descriptor.");
> > txdp = &txq->tx_ring[txq->tx_tail + 1];
> > - txdp->buffer_addr = rte_cpu_to_le_64(pf->fdir.dma_addr);
> > + txdp->buffer_addr = rte_cpu_to_le_64(pf->fdir.dma_addr[txq->tx_tail
> > +/ 2]);
> > +
> [txq->tx_tail / 2] is not readable, how about use the avail pkt you get
> directly?
> Or another index to identify it?
Have replaced with >> 1
> > td_cmd = I40E_TX_DESC_CMD_EOP |
> > I40E_TX_DESC_CMD_RS |
> > I40E_TX_DESC_CMD_DUMMY;
> > @@ -2100,25 +2184,34 @@ i40e_flow_fdir_filter_programming(struct
> i40e_pf *pf,
> > txq->tx_tail = 0;
> > /* Update the tx tail register */
> > rte_wmb();
> > +
> > + /* capture the previous error report(if any) from rx ring */
> > + while ((i40e_check_fdir_programming_status(rxq) < 0) &&
> > + (++retry_count < 100))
> > + PMD_DRV_LOG(INFO, "previous error report captured.");
> > +
> Why check FDIR ring for 100 times? And "&&" is used here, the log is only
> print if
> the 100th check fails?
No, it will print 100 times.
The purpose of this code is to clean up the fdir rx queue.
Have new an independent function for this
> >
> > --
> > 2.17.1