Re: [dpdk-dev] [PATCH 05/40] net/virtio: move PCI device init in dedicated file

[Maxime Coquelin <maxime.coquelin@redhat.com>]

On 1/5/21 10:19 PM, David Marchand wrote:
> On Sun, Dec 20, 2020 at 10:14 PM Maxime Coquelin
> <maxime.coquelin@redhat.com> wrote:
>> diff --git a/drivers/net/virtio/virtio_ethdev.c b/drivers/net/virtio/virtio_ethdev.c
>> index 99a5a1bb88..ca21a019e5 100644
>> --- a/drivers/net/virtio/virtio_ethdev.c
>> +++ b/drivers/net/virtio/virtio_ethdev.c
> 
> [...]
> 
>> @@ -2135,52 +2078,7 @@ virtio_dev_devargs_parse(struct rte_devargs *devargs, int *vdpa,
>>         return ret;
>>  }
>>
>> -static int eth_virtio_pci_probe(struct rte_pci_driver *pci_drv __rte_unused,
>> -       struct rte_pci_device *pci_dev)
>> -{
>> -       int vdpa = 0;
>> -       int ret = 0;
>> -
>> -       ret = virtio_dev_devargs_parse(pci_dev->device.devargs, &vdpa, NULL,
>> -               NULL);
>> -       if (ret < 0) {
>> -               PMD_INIT_LOG(ERR, "devargs parsing is failed");
>> -               return ret;
>> -       }
>> -       /* virtio pmd skips probe if device needs to work in vdpa mode */
>> -       if (vdpa == 1)
>> -               return 1;
>> -
>> -       return rte_eth_dev_pci_generic_probe(pci_dev, sizeof(struct virtio_pci_dev),
>> -               eth_virtio_dev_init);
>> -}
>> -
>> -static int eth_virtio_pci_remove(struct rte_pci_device *pci_dev)
>> -{
>> -       int ret;
>> -
>> -       ret = rte_eth_dev_pci_generic_remove(pci_dev, eth_virtio_dev_uninit);
>> -       /* Port has already been released by close. */
>> -       if (ret == -ENODEV)
>> -               ret = 0;
>> -       return ret;
>> -}
>> -
>> -static struct rte_pci_driver rte_virtio_pmd = {
>> -       .driver = {
>> -               .name = "net_virtio",
>> -       },
>> -       .id_table = pci_id_virtio_map,
>> -       .drv_flags = 0,
>> -       .probe = eth_virtio_pci_probe,
>> -       .remove = eth_virtio_pci_remove,
>> -};
>>
>> -RTE_INIT(rte_virtio_pmd_init)
>> -{
>> -       rte_eal_iopl_init();
>> -       rte_pci_register(&rte_virtio_pmd);
>> -}
>>
> 
> Leaving three empty lines if I count correctly.
> 
> 
>>  static bool
>>  rx_offload_enabled(struct virtio_hw *hw)
>> @@ -2521,7 +2419,7 @@ static void virtio_dev_free_mbufs(struct rte_eth_dev *dev)
>>  /*
>>   * Stop device: disable interrupt and mark link down
>>   */
>> -static int
>> +int
>>  virtio_dev_stop(struct rte_eth_dev *dev)
>>  {
>>         struct virtio_hw *hw = dev->data->dev_private;
>> @@ -2673,7 +2571,5 @@ __rte_unused uint8_t is_rx)
>>  }
>>
>>  RTE_PMD_EXPORT_NAME(net_virtio, __COUNTER__);
> 
> This belongs with the rest of the pci driver declarations.
> 
> $ ./usertools/dpdk-pmdinfo.py
> $HOME/builds/build-gcc-shared/drivers/librte_net_virtio.so
> PMD NAME: net_virtio_user
> PMD PARAMETERS: path=<path> mac=<mac addr> cq=<int> queue_size=<int>
> queues=<int> iface=<string> server=<0|1> mrg_rxbuf=<0|1>
> in_order=<0|1> packed_vq=<0|1> speed=<int> vectorized=<0|1>
> 
> PMD NAME: net_virtio
> 
> ^^^
> Here, I would expect the pci table and the kmod dependencies.
> 
> 
> This makes me realise that the net_virtio_user driver is not exported
> (but it seems to work without it.. interesting).

As discussed offlist, I have moved RTE_PMD_EXPORT_NAME to
virtio_pci_ethdev.c, and I now get expected output:

$ ./usertools/dpdk-pmdinfo.py build/drivers/librte_net_virtio.so
PMD NAME: net_virtio_user
PMD PARAMETERS: path=<path> mac=<mac addr> cq=<int> queue_size=<int>
queues=<int> iface=<string> server=<0|1> mrg_rxbuf=<0|1> in_order=<0|1>
packed_vq=<0|1> speed=<int> vectorized=<0|1>

PMD NAME: net_virtio
PMD KMOD DEPENDENCIES: * igb_uio | uio_pci_generic | vfio-pci
PMD HW SUPPORT:
 Red Hat, Inc. (1af4) : Virtio network device (1000) (All Subdevices)
 Red Hat, Inc. (1af4) : Virtio network device (1041) (All Subdevices)

> 
>> -RTE_PMD_REGISTER_PCI_TABLE(net_virtio, pci_id_virtio_map);
>> -RTE_PMD_REGISTER_KMOD_DEP(net_virtio, "* igb_uio | uio_pci_generic | vfio-pci");
>>  RTE_LOG_REGISTER(virtio_logtype_init, pmd.net.virtio.init, NOTICE);
>>  RTE_LOG_REGISTER(virtio_logtype_driver, pmd.net.virtio.driver, NOTICE);
>> diff --git a/drivers/net/virtio/virtio_ethdev.h b/drivers/net/virtio/virtio_ethdev.h
>> index b7d52d497f..13395937c8 100644
>> --- a/drivers/net/virtio/virtio_ethdev.h
>> +++ b/drivers/net/virtio/virtio_ethdev.h
>> @@ -117,6 +117,8 @@ void virtio_interrupt_handler(void *param);
>>
>>  int virtio_dev_pause(struct rte_eth_dev *dev);
>>  void virtio_dev_resume(struct rte_eth_dev *dev);
>> +int virtio_dev_stop(struct rte_eth_dev *dev);
>> +int virtio_dev_close(struct rte_eth_dev *dev);
>>  int virtio_inject_pkts(struct rte_eth_dev *dev, struct rte_mbuf **tx_pkts,
>>                 int nb_pkts);
>>
>> diff --git a/drivers/net/virtio/virtio_pci_ethdev.c b/drivers/net/virtio/virtio_pci_ethdev.c
>> new file mode 100644
>> index 0000000000..9c0935068e
>> --- /dev/null
>> +++ b/drivers/net/virtio/virtio_pci_ethdev.c
>> @@ -0,0 +1,148 @@
>> +/* SPDX-License-Identifier: BSD-3-Clause
>> + * Copyright(c) 2010-2016 Intel Corporation
>> + */
>> +
>> +#include <stdint.h>
>> +#include <string.h>
>> +#include <stdio.h>
>> +#include <errno.h>
>> +#include <unistd.h>
>> +
>> +#include <rte_ethdev_driver.h>
>> +#include <rte_ethdev_pci.h>
>> +#include <rte_pci.h>
>> +#include <rte_bus_pci.h>
>> +#include <rte_errno.h>
>> +
>> +#include <rte_memory.h>
>> +#include <rte_eal.h>
>> +#include <rte_dev.h>
>> +#include <rte_kvargs.h>
>> +
>> +#include "virtio_ethdev.h"
>> +#include "virtio_pci.h"
>> +#include "virtio_logs.h"
>> +
>> +/*
>> + * The set of PCI devices this driver supports
>> + */
>> +static const struct rte_pci_id pci_id_virtio_map[] = {
>> +       { RTE_PCI_DEVICE(VIRTIO_PCI_VENDORID, VIRTIO_PCI_LEGACY_DEVICEID_NET) },
>> +       { RTE_PCI_DEVICE(VIRTIO_PCI_VENDORID, VIRTIO_PCI_MODERN_DEVICEID_NET) },
>> +       { .vendor_id = 0, /* sentinel */ },
>> +};
>> +
>> +static int
>> +eth_virtio_pci_init(struct rte_eth_dev *eth_dev)
>> +{
>> +       return eth_virtio_dev_init(eth_dev);
>> +}
>> +
>> +static int
>> +eth_virtio_pci_uninit(struct rte_eth_dev *eth_dev)
>> +{
>> +       int ret;
>> +       PMD_INIT_FUNC_TRACE();
>> +
>> +       if (rte_eal_process_type() == RTE_PROC_SECONDARY)
>> +               return 0;
>> +
>> +       ret = virtio_dev_stop(eth_dev);
>> +       virtio_dev_close(eth_dev);
>> +
>> +       PMD_INIT_LOG(DEBUG, "dev_uninit completed");
>> +
>> +       return ret;
>> +}
>> +
>> +static int vdpa_check_handler(__rte_unused const char *key,
>> +               const char *value, void *ret_val)
>> +{
>> +       if (strcmp(value, "1") == 0)
>> +               *(int *)ret_val = 1;
>> +       else
>> +               *(int *)ret_val = 0;
>> +
>> +       return 0;
>> +}
>> +
>> +#define VIRTIO_ARG_VDPA       "vdpa"
>> +
>> +static int
>> +virtio_pci_devargs_parse(struct rte_devargs *devargs, int *vdpa)
>> +{
>> +       struct rte_kvargs *kvlist;
>> +       int ret = 0;
>> +
>> +       if (devargs == NULL)
>> +               return 0;
>> +
>> +       kvlist = rte_kvargs_parse(devargs->args, NULL);
>> +       if (kvlist == NULL) {
>> +               PMD_INIT_LOG(ERR, "error when parsing param");
>> +               return 0;
>> +       }
>> +
>> +       if (vdpa && rte_kvargs_count(kvlist, VIRTIO_ARG_VDPA) == 1) {
> 
> I would remove this check on vdpa pointer being NULL, as it gets
> passed on the stack by a single caller in this file.

I agree this is not necessary.

> 
>> +               /* vdpa mode selected when there's a key-value pair:
>> +                * vdpa=1
>> +                */
>> +               ret = rte_kvargs_process(kvlist, VIRTIO_ARG_VDPA,
>> +                               vdpa_check_handler, vdpa);
>> +               if (ret < 0)
>> +                       PMD_INIT_LOG(ERR, "Failed to parse %s", VIRTIO_ARG_VDPA);
>> +       }
>> +
>> +       rte_kvargs_free(kvlist);
>> +
>> +       return ret;
>> +}
>> +
>> +static int eth_virtio_pci_probe(struct rte_pci_driver *pci_drv __rte_unused,
>> +       struct rte_pci_device *pci_dev)
>> +{
>> +       int vdpa = 0;
>> +       int ret = 0;
>> +
>> +       ret = virtio_pci_devargs_parse(pci_dev->device.devargs, &vdpa);
>> +       if (ret < 0) {
>> +               PMD_INIT_LOG(ERR, "devargs parsing is failed");
>> +               return ret;
>> +       }
>> +       /* virtio pmd skips probe if device needs to work in vdpa mode */
>> +       if (vdpa == 1)
>> +               return 1;
>> +
>> +       return rte_eth_dev_pci_generic_probe(pci_dev, sizeof(struct virtio_pci_dev),
>> +               eth_virtio_pci_init);
>> +}
>> +
>> +static int eth_virtio_pci_remove(struct rte_pci_device *pci_dev)
>> +{
>> +       int ret;
>> +
>> +       ret = rte_eth_dev_pci_generic_remove(pci_dev, eth_virtio_pci_uninit);
>> +       /* Port has already been released by close. */
>> +       if (ret == -ENODEV)
>> +               ret = 0;
>> +       return ret;
>> +}
>> +
>> +static struct rte_pci_driver rte_virtio_pmd = {
> 
> This seems too generic.
> 
> virtio_pci_pmd ?

virtio_net_pci_pmd is even better.

> 
>> +       .driver = {
>> +               .name = "net_virtio",

I keept it as is here not to break tools relying on driver name.
Makes sense?

>> +       },
>> +       .id_table = pci_id_virtio_map,
>> +       .drv_flags = 0,
>> +       .probe = eth_virtio_pci_probe,
>> +       .remove = eth_virtio_pci_remove,
>> +};
>> +
>> +RTE_INIT(rte_virtio_pmd_init)
> 
> virtio_pci_pmd_init ?
> 

rte_virtio_net_pci_pmd_init

> 
>> +{
>> +       rte_eal_iopl_init();
>> +       rte_pci_register(&rte_virtio_pmd);
>> +}
>> +
>> +RTE_PMD_REGISTER_PCI_TABLE(net_virtio, pci_id_virtio_map);
>> +RTE_PMD_REGISTER_KMOD_DEP(net_virtio, "* igb_uio | uio_pci_generic | vfio-pci");
> 
> 
> --
> David Marchand
>