On Thu, Jun 08, 2017 at 12:45:17PM +0200, Jan Blunck wrote:
> On Wed, Jun 7, 2017 at 10:03 PM, Gaëtan Rivet <gaetan.ri...@6wind.com> wrote:
> > On Wed, Jun 07, 2017 at 07:28:07PM +0200, Jan Blunck wrote:
> >> On Wed, May 24, 2017 at 5:12 PM, Gaetan Rivet <gaetan.ri...@6wind.com>
> >> wrote:
> >> > Find which bus should be able to parse this device name into an internal
> >> > device representation.
> >> >
> >>
> >> No, please don't add this. One should know to what bus a device
> >> belongs to before plugging it. Artificially encoding the parent bus
> >> into the device name is not the right thing to do. Please keep those
> >> things separate.
> >>
> >
>
> When plugging a device the users know about:
> - bus name
> - device name
>
> Its not the case that the users invent the device names out of thin
> air. The EAL shouldn't codify what the users of the EAL already know
> about.
>
>
Yes, but in that case the user is forced to explicitly name the bus used
for a device.
I think it might be sufficient to have this as a private function to the
EAL, as it is currently only used within the rte_devargs parsing.
Applications could use this helper to recognize a bus from a device
name, but this is contrived.
> > The EAL has no way to know this currently. As you noted, it has to know
> > onto which bus a device belongs before plugging it.
> >
> >> > Signed-off-by: Gaetan Rivet <gaetan.ri...@6wind.com>
> >> > ---
> >> > lib/librte_eal/bsdapp/eal/rte_eal_version.map | 1 +
> >> > lib/librte_eal/common/eal_common_bus.c | 15 +++++++++++++++
> >> > lib/librte_eal/common/include/rte_bus.h | 12 ++++++++++++
> >> > lib/librte_eal/linuxapp/eal/rte_eal_version.map | 1 +
> >> > 4 files changed, 29 insertions(+)
> >> >
> >> > diff --git a/lib/librte_eal/bsdapp/eal/rte_eal_version.map
> >> > b/lib/librte_eal/bsdapp/eal/rte_eal_version.map
> >> > index 3517d74..04fa882 100644
> >> > --- a/lib/librte_eal/bsdapp/eal/rte_eal_version.map
> >> > +++ b/lib/librte_eal/bsdapp/eal/rte_eal_version.map
> >> > @@ -202,5 +202,6 @@ DPDK_17.08 {
> >> > global:
> >> >
> >> > rte_bus_from_name;
> >> > + rte_bus_from_dev;
> >> >
> >> > } DPDK_17.05;
> >> > diff --git a/lib/librte_eal/common/eal_common_bus.c
> >> > b/lib/librte_eal/common/eal_common_bus.c
> >> > index 7977190..08fff60 100644
> >> > --- a/lib/librte_eal/common/eal_common_bus.c
> >> > +++ b/lib/librte_eal/common/eal_common_bus.c
> >> > @@ -242,3 +242,18 @@ rte_bus_from_name(const char *str)
> >> > return NULL;
> >> > return rte_bus_find(bus_cmp_name, str);
> >> > }
> >> > +
> >> > +static int
> >> > +bus_can_parse(const struct rte_bus *bus, const void *_name)
> >> > +{
> >> > + const char *name = _name;
> >> > +
> >> > + return (bus->parse && !bus->parse(name, NULL));
> >> > +}
> >> > +
> >> > +/* find a bus capable of parsing a device description */
> >> > +struct rte_bus *
> >> > +rte_bus_from_dev(const char *str)
> >> > +{
> >> > + return rte_bus_find(bus_can_parse, str);
> >> > +}
> >> > diff --git a/lib/librte_eal/common/include/rte_bus.h
> >> > b/lib/librte_eal/common/include/rte_bus.h
> >> > index 5b87ac4..0b48e66 100644
> >> > --- a/lib/librte_eal/common/include/rte_bus.h
> >> > +++ b/lib/librte_eal/common/include/rte_bus.h
> >> > @@ -251,6 +251,18 @@ struct rte_bus *rte_bus_find_by_device(const struct
> >> > rte_device *dev);
> >> > struct rte_bus *rte_bus_from_name(const char *str);
> >> >
> >> > /**
> >> > + * Find a bus capable of identifying a device.
> >> > + *
> >> > + * @param str
> >> > + * A device identifier (PCI address, virtual PMD name, ...).
> >> > + *
> >> > + * @return
> >> > + * A valid bus structure if found.
> >> > + * NULL if no bus is able to parse this device.
> >> > + */
> >> > +struct rte_bus *rte_bus_from_dev(const char *str);
> >> > +
> >> > +/**
> >> > * Helper for Bus registration.
> >> > * The constructor has higher priority than PMD constructors.
> >> > */
> >> > diff --git a/lib/librte_eal/linuxapp/eal/rte_eal_version.map
> >> > b/lib/librte_eal/linuxapp/eal/rte_eal_version.map
> >> > index 6607acc..a5127d6 100644
> >> > --- a/lib/librte_eal/linuxapp/eal/rte_eal_version.map
> >> > +++ b/lib/librte_eal/linuxapp/eal/rte_eal_version.map
> >> > @@ -206,5 +206,6 @@ DPDK_17.08 {
> >> > global:
> >> >
> >> > rte_bus_from_name;
> >> > + rte_bus_from_dev;
> >> >
> >> > } DPDK_17.05;
> >> > --
> >> > 2.1.4
> >> >
> >
> > --
> > Gaėtan Rivet
> > 6WIND
--
Gaëtan Rivet
6WIND
