On Fri, Dec 22, 2017 at 02:41:16PM +0000, Remy Horton wrote: > Port Representors provide a logical presentation in DPDK of VF (virtual > function) ports for the purposes of control and monitoring. Each port > representor device represents a single VF and is associated with it's > parent physical function (PF) PMD which provides the back-end hooks for > the representor device ops and defines the control domain to which that > port belongs. This allows to use existing DPDK APIs to monitor and control > the port without the need to create and maintain VF specific APIs. > > +-----------------------------+ +---------------+ +---------------+ > | Control Plane | | Data Plane | | Data Plane | > | Application | | Application | | Application | > +-----------------------------+ +---------------+ +---------------+ > | eth dev api | | eth dev api | | eth dev api | > +-----------------------------+ +---------------+ +---------------+ > +-------+ +-------+ +-------+ +---------------+ +---------------+ > | PF0 | | Port | | Port | | VF0 PMD | | VF0 PMD | > | PMD <--+ Rep 0 | | Rep 1 | +---------------+ +------+--------+ > | | | PMD | | PMD | | > +---+--^+ +-------+ +-+-----+ | > | | | | | > | +----------------+ | | > | | | > | | | > +--------------------------------+ | > | | HW (logical view) | | | > | --+------+ +-------+ +---+---+ | | > | | PF | | VF0 | | VF1 | | | > | | | | | | +----------------------------+ > | +--------+ +-------+ +-------+ | > | +----------------------------+ | > | | VEB | | > | +----------------------------+ | > | +--------+ | > | | Port | | > | | 0 | | > | +--------+ | > +--------------------------------+ >
How does this mesh with the notion of port ownership that we've been discussing in other threads? In that thread, we've been discussing the need for a single execution context to have exclusive access to the hardware for the purposes of configuration and data i/o, and for the application/execution context to be responsible for co-ordination of any shared use of a device. In this feature however, the notion of a Port Representor creates an alias to the same hardware funciton (VF), where both aliases (in the control and data plan) have parallel access to the hardware, in such a way that co-ordination between the two is largely impossible (unless you want to make the data plane application explicity aware of control plane actiivy). Neil
