[PATCH v5 3/8] net/gve: add support for device initialization

[Li, Xiaoyun]

Hi

> -----Original Message-----
> From: Ferruh Yigit <ferruh.yigit at amd.com>
> Sent: Wednesday, October 19, 2022 14:46
> To: Guo, Junfeng <junfeng.guo at intel.com>; Zhang, Qi Z
> <qi.z.zhang at intel.com>; Wu, Jingjing <jingjing.wu at intel.com>
> Cc: ferruh.yigit at xilinx.com; dev at dpdk.org; Li, Xiaoyun
> <xiaoyun.li at intel.com>; awogbemila at google.com; Richardson, Bruce
> <bruce.richardson at intel.com>; Lin, Xueqin <xueqin.lin at intel.com>; Wang,
> Haiyue <haiyue.wang at intel.com>
> Subject: Re: [PATCH v5 3/8] net/gve: add support for device initialization
> 
> On 10/10/2022 11:17 AM, Junfeng Guo wrote:
> >
> > Support device init and add following devops skeleton:
> >   - dev_configure
> >   - dev_start
> >   - dev_stop
> >   - dev_close
> >
> > Note that build system (including doc) is also added in this patch.
> >
> > Signed-off-by: Haiyue Wang <haiyue.wang at intel.com>
> > Signed-off-by: Xiaoyun Li <xiaoyun.li at intel.com>
> > Signed-off-by: Junfeng Guo <junfeng.guo at intel.com>
> 
> <...>
> 
> > diff --git a/doc/guides/rel_notes/release_22_11.rst
> > b/doc/guides/rel_notes/release_22_11.rst
> > index fbb575255f..c1162ea1a4 100644
> > --- a/doc/guides/rel_notes/release_22_11.rst
> > +++ b/doc/guides/rel_notes/release_22_11.rst
> > @@ -200,6 +200,11 @@ New Features
> >     into single event containing ``rte_event_vector``
> >     whose event type is ``RTE_EVENT_TYPE_CRYPTODEV_VECTOR``.
> >
> > +* **Added GVE net PMD**
> > +
> > +  * Added the new ``gve`` net driver for Google Virtual Ethernet devices.
> > +  * See the :doc:`../nics/gve` NIC guide for more details on this new driver.
> > +
> >
> 
> Can you please move the block amaong the other ethdev drivers, as
> alphabetically sorted?
> 
> <...>
> 
> > +static int
> > +gve_dev_init(struct rte_eth_dev *eth_dev) {
> > +       struct gve_priv *priv = eth_dev->data->dev_private;
> > +       int max_tx_queues, max_rx_queues;
> > +       struct rte_pci_device *pci_dev;
> > +       struct gve_registers *reg_bar;
> > +       rte_be32_t *db_bar;
> > +       int err;
> > +
> > +       eth_dev->dev_ops = &gve_eth_dev_ops;
> > +
> > +       if (rte_eal_process_type() != RTE_PROC_PRIMARY)
> > +               return 0;
> > +
> > +       pci_dev = RTE_DEV_TO_PCI(eth_dev->device);
> > +
> > +       reg_bar = pci_dev->mem_resource[GVE_REG_BAR].addr;
> > +       if (!reg_bar) {
> > +               PMD_DRV_LOG(ERR, "Failed to map pci bar!");
> > +               return -ENOMEM;
> > +       }
> > +
> > +       db_bar = pci_dev->mem_resource[GVE_DB_BAR].addr;
> > +       if (!db_bar) {
> > +               PMD_DRV_LOG(ERR, "Failed to map doorbell bar!");
> > +               return -ENOMEM;
> > +       }
> > +
> > +       gve_write_version(&reg_bar->driver_version);
> > +       /* Get max queues to alloc etherdev */
> > +       max_tx_queues = ioread32be(&reg_bar->max_tx_queues);
> > +       max_rx_queues = ioread32be(&reg_bar->max_rx_queues);
> > +
> > +       priv->reg_bar0 = reg_bar;
> > +       priv->db_bar2 = db_bar;
> > +       priv->pci_dev = pci_dev;
> > +       priv->state_flags = 0x0;
> > +
> > +       priv->max_nb_txq = max_tx_queues;
> > +       priv->max_nb_rxq = max_rx_queues;
> > +
> > +       err = gve_init_priv(priv, false);
> > +       if (err)
> > +               return err;
> > +
> > +       eth_dev->data->mac_addrs = rte_zmalloc("gve_mac", sizeof(struct
> rte_ether_addr), 0);
> > +       if (!eth_dev->data->mac_addrs) {
> > +               PMD_DRV_LOG(ERR, "Failed to allocate memory to store mac
> address");
> > +               return -ENOMEM;
> > +       }
> > +       rte_ether_addr_copy(&priv->dev_addr,
> > + eth_dev->data->mac_addrs);
> > +
> 
> Is anything assinged to 'priv->dev_addr' to copy?
> Also since there is a 'priv->dev_addr' field, why not use it directly, instead of
> allocating memory for 'eth_dev->data->mac_addrs'?
> I mean why not "eth_dev->data->mac_addrs = &priv->dev_addr"?

Makes sense. There's no need to allocate a new memory. @Guo, Junfeng Can you update this?
> 
> <...>
> 
> > +struct gve_priv {
> > +       struct gve_irq_db *irq_dbs; /* array of num_ntfy_blks */
> > +       const struct rte_memzone *irq_dbs_mz;
> > +       uint32_t mgmt_msix_idx;
> > +       rte_be32_t *cnt_array; /* array of num_event_counters */
> > +       const struct rte_memzone *cnt_array_mz;
> > +
> > +       uint16_t num_event_counters;
> > +       uint16_t tx_desc_cnt; /* txq size */
> > +       uint16_t rx_desc_cnt; /* rxq size */
> > +       uint16_t tx_pages_per_qpl; /* tx buffer length */
> > +       uint16_t rx_data_slot_cnt; /* rx buffer length */
> 
> These fields are not used in this patch, I guess some will be used in datapath
> patch.

This is needed for base code gve_adminq.c not for datapath. Most of the stuff in gve_priv is for gve_adminq.c.
The adminq will update this info which dpdk pmd will need later. Compiler will complain if these don't exsit.

> 
> Can you please only add fields that is used in the patch? This way it will be
> clear in which functionality that field is used and enable to detect not used
> fields.
> We are accepting batch updates for base code, but this is dpdk related code,
> lets only add things that are used when they are used.
> Same for all data structures.
> 
> <...>
> 
> > diff --git a/drivers/net/gve/version.map b/drivers/net/gve/version.map
> > new file mode 100644 index 0000000000..c2e0723b4c
> > --- /dev/null
> > +++ b/drivers/net/gve/version.map
> > @@ -0,0 +1,3 @@
> > +DPDK_22 {
> 
> DPDK_23