Hi Stephan
From: Stephen Hemminger, Tuesday, January 9, 2018 8:51 PM
> To: Matan Azrad <ma...@mellanox.com>
> Cc: Ferruh Yigit <ferruh.yi...@intel.com>; Thomas Monjalon
> <tho...@monjalon.net>; dev@dpdk.org; Raslan Darawsheh
> <rasl...@mellanox.com>
> Subject: Re: [PATCH v3 6/8] net/vdev_netvsc: skip routed netvsc probing
>
> On Tue, 9 Jan 2018 14:47:31 +0000
> Matan Azrad <ma...@mellanox.com> wrote:
>
> > NetVSC netdevices which are already routed should not be probed
> > because they are used for management purposes by the HyperV.
> >
> > prevent routed netvsc devices probing.
> >
> > Signed-off-by: Raslan Darawsheh <rasl...@mellanox.com>
> > Signed-off-by: Matan Azrad <ma...@mellanox.com>
> > ---
> > doc/guides/nics/vdev_netvsc.rst | 2 +-
> > drivers/net/vdev_netvsc/vdev_netvsc.c | 46
> > +++++++++++++++++++++++++++++++++++
> > 2 files changed, 47 insertions(+), 1 deletion(-)
> >
> > diff --git a/doc/guides/nics/vdev_netvsc.rst
> > b/doc/guides/nics/vdev_netvsc.rst index fde1fb8..f779862 100644
> > --- a/doc/guides/nics/vdev_netvsc.rst
> > +++ b/doc/guides/nics/vdev_netvsc.rst
> > @@ -87,4 +87,4 @@ The following device parameters are supported:
> > MAC address.
> >
> > Not specifying either ``iface`` or ``mac`` makes this driver attach
> > itself to -all NetVSC interfaces found on the system.
> > +all unrouted NetVSC interfaces found on the system.
> > diff --git a/drivers/net/vdev_netvsc/vdev_netvsc.c
> > b/drivers/net/vdev_netvsc/vdev_netvsc.c
> > index 3d8895b..4295b92 100644
> > --- a/drivers/net/vdev_netvsc/vdev_netvsc.c
> > +++ b/drivers/net/vdev_netvsc/vdev_netvsc.c
> > @@ -38,6 +38,7 @@
> > #define VDEV_NETVSC_PROBE_MS 1000
> >
> > #define NETVSC_CLASS_ID "{f8615163-df3e-46c5-913f-f2d2f965ed0e}"
> > +#define NETVSC_MAX_ROUTE_LINE_SIZE 300
> >
> > #define DRV_LOG(level, ...) \
> > rte_log(RTE_LOG_ ## level, \
> > @@ -192,6 +193,44 @@ static LIST_HEAD(, vdev_netvsc_ctx)
> > vdev_netvsc_ctx_list = }
> >
> > /**
> > + * Determine if a network interface has a route.
> > + *
> > + * @param[in] name
> > + * Network device name.
> > + *
> > + * @return
> > + * A nonzero value when interface has an route. In case of error,
> > + * rte_errno is updated and 0 returned.
> > + */
> > +static int
> > +vdev_netvsc_has_route(const char *name) {
> > + FILE *fp;
> > + int ret = 0;
> > + char route[NETVSC_MAX_ROUTE_LINE_SIZE];
> > + char *netdev;
> > +
> > + fp = fopen("/proc/net/route", "r");
> > + if (!fp) {
> > + rte_errno = errno;
> > + return 0;
> > + }
> > + while (fgets(route, NETVSC_MAX_ROUTE_LINE_SIZE, fp) != NULL) {
> > + netdev = strtok(route, "\t");
> > + if (strcmp(netdev, name) == 0) {
> > + ret = 1;
> > + break;
> > + }
> > + /* Move file pointer to the next line. */
> > + while (strchr(route, '\n') == NULL &&
> > + fgets(route, NETVSC_MAX_ROUTE_LINE_SIZE, fp) !=
> NULL)
> > + ;
> > + }
> > + fclose(fp);
> > + return ret;
> > +}
>
> In many ways /proc/net/route is legacy intervace.
> And system may have 1 M routes.
>
> Maybe there is faster way to do this with netlink by looking to see if there
> is
> an address associated with the interface.
Actually this is control path, we don't care about performance very much.
But I can get other idea here, Do you have suggestion?
Thanks!
