Hi John, Mon, Feb 22, 2016 at 10:32:47PM IST, john.fastab...@gmail.com wrote: >On 16-02-22 10:32 AM, Jiri Pirko wrote: >> From: Ido Schimmel <ido...@mellanox.com> >> >> When splitting a port we replace it with 2 or 4 other ports. To be able >> to do that we need to remove the original port netdev and unmap it from >> its module. However, we first mark it as disabled, as active ports >> cannot be unmapped. >> >> Signed-off-by: Ido Schimmel <ido...@mellanox.com> >> Signed-off-by: Jiri Pirko <j...@mellanox.com> >> --- > >Hi Jiri, Ido, > >You've sort of lost me on this port splitting/unsplitting thread. What >does this actually do? Are you just creating two netdevs and LAGing them >in the hardware, I'm guessing not or you wouldn't have some device API >for it and would do it using normal methods.
Yep, it's not LAG. You basically have a mapping between a physical module and a local port, which is represented by a port netdev. Each module has 4 lanes, so if you connect a splitter (say a 2x) you can map each 2 lanes to a different port and assign each a new local port. These are completely independent from each other, but they can only give you 50Gb/s max, as opposed to the original 100Gb/s (as it had 4 lanes all to itself). > >If its something to do with physical layout of the board itself why >don't you trigger this based on some init time introspection or an >interrupt if someone plugs in a port splitting cable/module (does that >exist?). We currently don't have an event that tells us that a splitter is connected. Also, had we created / destroyed these based on events, then an accidental removal of the splitter would cause all the configuration setup on these ports to disappear (say VLANs on a bridged port, unicast flooding etc.). Thanks. > >Thanks, >John > >
