[dpdk-dev] [RFC PATCH 4/4] ethdev: add helpers to move to the new offloads API

[Shahaf Shuler]

Wednesday, August 23, 2017 3:29 PM, Ananyev, Konstantin:
> 
> 
> > -----Original Message-----
> > From: dev [mailto:dev-bounces at dpdk.org] On Behalf Of Shahaf Shuler
> > Sent: Monday, August 7, 2017 1:55 PM
> > To: dev at dpdk.org
> > Subject: [dpdk-dev] [RFC PATCH 4/4] ethdev: add helpers to move to the
> > new offloads API
> >
> > A new offloads API was introduced by commits:
> >
> > commit 8b07fcae6061 ("ethdev: introduce Tx queue offloads API") commit
> > c6504557763e ("ethdev: introduce Rx queue offloads API")
> >
> > In order to enable PMDs to support only one of the APIs, and
> > applications to avoid branching according to the underlying device a
> > copy functions to/from the old/new APIs were added.
> >
> > Signed-off-by: Shahaf Shuler <shahafs at mellanox.com>
> > ---
> >  lib/librte_ether/rte_ethdev.c | 140
> > +++++++++++++++++++++++++++++++++++++
> >  1 file changed, 140 insertions(+)
> >
> > diff --git a/lib/librte_ether/rte_ethdev.c
> > b/lib/librte_ether/rte_ethdev.c index f73307e99..2b4a28c97 100644
> > --- a/lib/librte_ether/rte_ethdev.c
> > +++ b/lib/librte_ether/rte_ethdev.c
> > @@ -1003,6 +1003,63 @@ rte_eth_dev_close(uint8_t port_id)
> >  	dev->data->tx_queues = NULL;
> >  }
> >
> > +/**
> > + * A copy function from rxmode offloads API to rte_eth_rxq_conf
> > + * offloads API, to enable PMDs to support only one of the APIs.
> > + */
> > +static void
> > +rte_eth_copy_rxmode_offloads(struct rte_eth_rxmode *rxmode,
> > +			     struct rte_eth_rxq_conf *rxq_conf) {
> > +	if (rxmode->header_split == 1)
> > +		rxq_conf->offloads |= DEV_RX_OFFLOAD_HEADER_SPLIT;
> > +	if (rxmode->hw_ip_checksum == 1)
> > +		rxq_conf->offloads |= DEV_RX_OFFLOAD_CHECKSUM;
> > +	if (rxmode->hw_vlan_filter == 1)
> > +		rxq_conf->offloads |= DEV_RX_OFFLOAD_VLAN_FILTER;
> > +	if (rxmode->hw_vlan_strip == 1)
> > +		rxq_conf->offloads |= DEV_RX_OFFLOAD_VLAN_STRIP;
> > +	if (rxmode->hw_vlan_extend == 1)
> > +		rxq_conf->offloads |= DEV_RX_OFFLOAD_VLAN_EXTEND;
> > +	if (rxmode->jumbo_frame == 1)
> > +		rxq_conf->offloads |= DEV_RX_OFFLOAD_JUMBO_FRAME;
> > +	if (rxmode->hw_strip_crc == 1)
> > +		rxq_conf->offloads |= DEV_RX_OFFLOAD_CRC_STRIP;
> > +	if (rxmode->enable_scatter == 1)
> > +		rxq_conf->offloads |= DEV_RX_OFFLOAD_SCATTER;
> > +	if (rxmode->enable_lro == 1)
> > +		rxq_conf->offloads |= DEV_RX_OFFLOAD_LRO; }
> > +
> > +/**
> > + * A copy function between rte_eth_rxq_conf offloads API to rxmode
> > + * offloads API, to enable application to be agnostic to the PMD
> > +supported
> > + * offload API.
> > + */
> > +static void
> > +rte_eth_copy_rxq_offloads(struct rte_eth_rxmode *rxmode,
> > +			  struct rte_eth_rxq_conf *rxq_conf) {
> > +	if (rxq_conf->offloads & DEV_RX_OFFLOAD_HEADER_SPLIT)
> > +		rxmode->header_split = 1;
> > +	if (rxq_conf->offloads & DEV_RX_OFFLOAD_CHECKSUM)
> > +		rxmode->hw_ip_checksum = 1;
> > +	if (rxq_conf->offloads & DEV_RX_OFFLOAD_VLAN_FILTER)
> > +		rxmode->hw_vlan_filter = 1;
> > +	if (rxq_conf->offloads & DEV_RX_OFFLOAD_VLAN_STRIP)
> > +		rxmode->hw_vlan_strip = 1;
> > +	if (rxq_conf->offloads & DEV_RX_OFFLOAD_VLAN_EXTEND)
> > +		rxmode->hw_vlan_extend = 1;
> > +	if (rxq_conf->offloads & DEV_RX_OFFLOAD_JUMBO_FRAME)
> > +		rxmode->jumbo_frame = 1;
> > +	if (rxq_conf->offloads & DEV_RX_OFFLOAD_CRC_STRIP)
> > +		rxmode->hw_strip_crc = 1;
> > +	if (rxq_conf->offloads & DEV_RX_OFFLOAD_SCATTER)
> > +		rxmode->enable_scatter = 1;
> > +	if (rxq_conf->offloads & DEV_RX_OFFLOAD_LRO)
> > +		rxmode->enable_lro = 1;
> > +}
> > +
> >  int
> >  rte_eth_rx_queue_setup(uint8_t port_id, uint16_t rx_queue_id,
> >  		       uint16_t nb_rx_desc, unsigned int socket_id, @@ -1083,6
> > +1140,37 @@ rte_eth_rx_queue_setup(uint8_t port_id, uint16_t
> rx_queue_id,
> >  	if (rx_conf == NULL)
> >  		rx_conf = &dev_info.default_rxconf;
> >
> > +	if ((dev->data->dev_flags & RTE_ETH_DEV_RXQ_OFFLOAD) &&
> > +	    (dev->data->dev_conf.rxmode.ignore == 0)) {
> > +		rte_eth_copy_rxmode_offloads(&dev->data-
> >dev_conf.rxmode,
> > +					     rx_conf);
> > +	} else if ((!(dev->data->dev_flags & RTE_ETH_DEV_RXQ_OFFLOAD))
> &&
> > +		   (dev->data->dev_conf.rxmode.ignore == 1)) {
> > +		int ret;
> > +		struct rte_eth_rxmode rxmode;
> > +
> > +		rte_eth_copy_rxq_offloads(&rxmode, rx_conf);
> > +		if (memcmp(&rxmode, &dev->data->dev_conf.rxmode,
> > +			   sizeof(rxmode))) {
> > +			/*
> > +			 * device which work with rxmode offloads API
> requires
> > +			 * a re-configuration in order to apply the new
> offloads
> > +			 * configuration.
> > +			 */
> > +			dev->data->dev_conf.rxmode = rxmode;
> > +			ret = rte_eth_dev_configure(port_id,
> > +					dev->data->nb_rx_queues,
> > +					dev->data->nb_tx_queues,
> > +					&dev->data->dev_conf);
> 
> 
> Hmm, and why we would need to reconfigure our device in the middle of rx
> queue setup?

The reason is the old Rx offloads API is configured on device configure. 
This if section is for applications which already moved to the new offload API however the underlying PMD still uses the old one.

> 
> > +			if (ret < 0) {
> > +				RTE_PMD_DEBUG_TRACE(
> > +					"unable to re-configure port %d "
> > +					"in order to apply rxq offloads "
> > +					"configuration\n", port_id);
> > +			}
> > +		}
> > +	}
> > +
> >  	ret = (*dev->dev_ops->rx_queue_setup)(dev, rx_queue_id,
> nb_rx_desc,
> >  					      socket_id, rx_conf, mp);
> 
> BTW, I don't see changes in any PMD for new offload flags?
> Is it because it is just a n RFC and full patch would contain such changes?

Yes this is because this is an RFC.
 
The full patch I intend will move all examples and testpmd to the new offloads API.
In addition it will include the mlx5 PMD support for the new offloads API. 

As I said on previous mail, I believe that the work to move the different PMDs to the new API should be done by their developers or maintainers.

> 
> 
> >  	if (!ret) {
> > @@ -1094,6 +1182,51 @@ rte_eth_rx_queue_setup(uint8_t port_id,
> uint16_t rx_queue_id,
> >  	return ret;
> >  }
> >
> > +/**
> > + * A copy function from txq_flags to rte_eth_txq_conf offloads API,
> > + * to enable PMDs to support only one of the APIs.
> > + */
> > +static void
> > +rte_eth_copy_txq_flags(struct rte_eth_txq_conf *txq_conf) {
> > +	uint32_t txq_flags = txq_conf->txq_flags
> > +	uint64_t *offloads = &txq_conf->offloads;
> > +
> > +	if (!(txq_flags & ETH_TXQ_FLAGS_NOMULTSEGS))
> > +		*offloads |= DEV_TX_OFFLOAD_MULTI_SEGS;
> > +	if (!(txq_flags & ETH_TXQ_FLAGS_NOVLANOFFL))
> > +		*offloads |= DEV_TX_OFFLOAD_VLAN_INSERT;
> > +	if (!(txq_flags & ETH_TXQ_FLAGS_NOXSUMSCTP))
> > +		*offloads |= DEV_TX_OFFLOAD_SCTP_CKSUM;
> > +	if (!(txq_flags & ETH_TXQ_FLAGS_NOXSUMUDP))
> > +		*offloads |= DEV_TX_OFFLOAD_UDP_CKSUM;
> > +	if (!(txq_flags & ETH_TXQ_FLAGS_NOXSUMTCP))
> > +		*offloads |= DEV_TX_OFFLOAD_TCP_CKSUM; }
> > +
> > +/**
> > + * A copy function between rte_eth_txq_conf offloads API to txq_flags
> > + * offloads API, to enable application to be agnostic to the PMD
> > +supported
> > + * API.
> > + */
> > +static void
> > +rte_eth_copy_txq_offloads(struct rte_eth_txq_conf *txq_conf) {
> > +	uint32_t *txq_flags = &txq_conf->txq_flags
> > +	uint64_t offloads = txq_conf->offloads;
> > +
> > +	if (!(offloads & DEV_TX_OFFLOAD_MULTI_SEGS))
> > +		*txq_flags |= ETH_TXQ_FLAGS_NOMULTSEGS;
> > +	if (!(offloads & DEV_TX_OFFLOAD_VLAN_INSERT))
> > +		*txq_flags |= ETH_TXQ_FLAGS_NOVLANOFFL;
> > +	if (!(offloads & DEV_TX_OFFLOAD_SCTP_CKSUM))
> > +		*txq_flags |= ETH_TXQ_FLAGS_NOXSUMSCTP;
> > +	if (!(offloads & DEV_TX_OFFLOAD_UDP_CKSUM))
> > +		*txq_flags |= ETH_TXQ_FLAGS_NOXSUMUDP;
> > +	if (!(offloads & DEV_TX_OFFLOAD_TCP_CKSUM))
> > +		*txq_flags |= ETH_TXQ_FLAGS_NOXSUMTCP; }
> > +
> >  int
> >  rte_eth_tx_queue_setup(uint8_t port_id, uint16_t tx_queue_id,
> >  		       uint16_t nb_tx_desc, unsigned int socket_id, @@ -1145,6
> > +1278,13 @@ rte_eth_tx_queue_setup(uint8_t port_id, uint16_t
> tx_queue_id,
> >  	if (tx_conf == NULL)
> >  		tx_conf = &dev_info.default_txconf;
> >
> > +	if ((dev->data->dev_flags & RTE_ETH_DEV_TXQ_OFFLOAD) &&
> > +	    (!(tx_conf->txq_flags & ETH_TXQ_FLAGS_IGNORE)))
> > +		rte_eth_copy_txq_flags(tx_conf);
> > +	else if (!(dev->data->dev_flags & RTE_ETH_DEV_TXQ_OFFLOAD) &&
> > +		   (tx_conf->txq_flags & ETH_TXQ_FLAGS_IGNORE))
> > +		rte_eth_copy_txq_offloads(tx_conf);
> > +
> 
> As I said in my previous mail - I think better to always convrert from old
> txq_flags to new TX offload flags and make each PMD to understand new
> offload values only.
> Konstantin
> 
> >  	return (*dev->dev_ops->tx_queue_setup)(dev, tx_queue_id,
> nb_tx_desc,
> >  					       socket_id, tx_conf);
> >  }
> > --
> > 2.12.0