Re: [dpdk-dev] [EXT] [PATCH v1 3/4] regexdev: add regexdev core functions

[Guy Kaneti <guyk@marvell.com>]

> -----Original Message-----
> From: dev <dev-bounces@dpdk.org> On Behalf Of Ori Kam
> Sent: Wednesday, April 08, 2020 11:40 AM
> To: Thomas Monjalon <thomas@monjalon.net>; Jerin Jacob Kollanukkaran
> <jerinj@marvell.com>; xiang.w.wang@intel.com; Pavan Nikhilesh
> Bhagavatula <pbhagavatula@marvell.com>
> Cc: dev@dpdk.org; Shahaf Shuler <shahafs@mellanox.com>;
> hemant.agrawal@nxp.com; Opher Reviv <opher@mellanox.com>; Alex
> Rosenbaum <alexr@mellanox.com>; Dovrat Zifroni <dovrat@marvell.com>;
> Prasun Kapoor <pkapoor@marvell.com>; nipun.gupta@nxp.com;
> bruce.richardson@intel.com; yang.a.hong@intel.com;
> harry.chang@intel.com; gu.jian1@zte.com.cn; shanjiangh@chinatelecom.cn;
> zhangy.yun@chinatelecom.cn; lixingfu@huachentel.com;
> wushuai@inspur.com; yuyingxia@yxlink.com;
> fanchenggang@sunyainfo.com; davidfgao@tencent.com;
> liuzhong1@chinaunicom.cn; zhaoyong11@huawei.com; oc@yunify.com;
> jim@netgate.com; hongjun.ni@intel.com; j.bromhead@titan-ic.com;
> deri@ntop.org; fc@napatech.com; arthur.su@lionic.com; Parav Pandit
> <parav@mellanox.com>
> Subject: Re: [dpdk-dev] [EXT] [PATCH v1 3/4] regexdev: add regexdev core
> functions
> 
> 
> 
> > -----Original Message-----
> > From: dev <dev-bounces@dpdk.org> On Behalf Of Thomas Monjalon
> > Sent: Monday, April 6, 2020 4:30 PM
> > To: Ori Kam <orika@mellanox.com>; Jerin Jacob Kollanukkaran
> > <jerinj@marvell.com>; xiang.w.wang@intel.com; Pavan Nikhilesh
> > Bhagavatula <pbhagavatula@marvell.com>
> > Cc: dev@dpdk.org; Shahaf Shuler <shahafs@mellanox.com>;
> > hemant.agrawal@nxp.com; Opher Reviv <opher@mellanox.com>; Alex
> > Rosenbaum <alexr@mellanox.com>; Dovrat Zifroni
> <dovrat@marvell.com>;
> > Prasun Kapoor <pkapoor@marvell.com>; nipun.gupta@nxp.com;
> > bruce.richardson@intel.com; yang.a.hong@intel.com;
> > harry.chang@intel.com; gu.jian1@zte.com.cn;
> > shanjiangh@chinatelecom.cn; zhangy.yun@chinatelecom.cn;
> > lixingfu@huachentel.com; wushuai@inspur.com; yuyingxia@yxlink.com;
> > fanchenggang@sunyainfo.com; davidfgao@tencent.com;
> > liuzhong1@chinaunicom.cn; zhaoyong11@huawei.com; oc@yunify.com;
> > jim@netgate.com; hongjun.ni@intel.com; j.bromhead@titan-ic.com;
> > deri@ntop.org; fc@napatech.com; arthur.su@lionic.com; Parav Pandit
> > <parav@mellanox.com>
> > Subject: Re: [dpdk-dev] [EXT] [PATCH v1 3/4] regexdev: add regexdev
> > core functions
> >
> > 06/04/2020 14:48, Pavan Nikhilesh Bhagavatula:
> > > > From: Pavan Nikhilesh Bhagavatula
> > > >> >> From: Pavan Nikhilesh Bhagavatula
> > > >> >>
> > > >> >> Looks like this implementation is incomplete?
> > > >> >> I don't see any pmd specific helper functions for @see
> > > >> >rte_cryptodev_pmd.c,
> > > >> >> rte_eventdev_pmd*
> > > >> >>
> > > >> >I think the current implementation includes all needed
> > > >> >functions, at least for the first stage.
> > > >> >You can find in rte_regexdev_driver.h the functions that should
> > > >> >be called by the PMD. We have the register / unregister which
> > > >> >acts the same
> > > >as
> > > >> >create
> > > >> >and destroy. For parsing argument the PMD may call
> > > >rte_kvargs_parse.
> > > >> >
> > > >>
> > > >> _driver.h should atleast include
> > > >> rte_regex_dev_pci_generic_probe/rte_regex_pmd_vdev_init
> > > >> else there would be a lot of code repetition and possibly
> > > >> udefined
> > > >behavior
> > > >> at the driver layer.
> > > >>
> > > >Why should they be included? At least in this stage, there is no
> > > >code to share ethdev why should we add code for the vdev?
> > >
> > > Ok I think I failed to communicate my concerns across.
> > > Let me retry
> > >
> > > 1. SW based regex devices such as PCRE/Hyperscan rely on vdev
> > > framework i.e. user needs to pass an EAL argument
> > > --vdev="regex_pcre" for the driver to initialize all the other EAL
> > > subsystems (ethdev, eventdev, cryptodev,
> > etc..)support this.
> >
> > vdev helpers do not have to be part of the first patches which define API.
> > It should be added when adding the first vdev driver.
> >
> > > 2. HW based independent regex devices that are exposed as PCI
> > > devices
> > would need
> > >  pci probe helpers.
> >
> > Same, PCI helpers can be added while adding the first PCI driver.
> >
> > We can synchronize about how to split the work, avoiding two
> > developers doing the same thing. But let's not mandate this work to be
> > done as part of this first series.
> >
> >
> I agree with Thomas, let's discuss this when adding the PMDs.

I am writing a now the Marvell OcteonTx2 PMD and I think that a PCI helper is missing.
When registering a PCI device, a .remove function is registered of type pci_remove_t *remove;

typedef int (pci_remove_t)(struct rte_pci_device *);
because this function receives struct rte_pci_device * as an argument 
It is required to have a helper function to retrieve struct rte_regexdev *dev based on the device name (or another way).
similar to rte_cryptodev_pmd_get_named_dev(const char *name)