Re: A new network interface send queue API

[Jason Thorpe <thorpej%me.com@localhost>]

> On Nov 12, 2023, at 10:36 PM, Kengo NAKAHARA <k-nakahara%iij.ad.jp@localhost> wrote:
> 
> Hi,
> 
> What do you think about Tx NIC multiqueue?
> 
> Currently, drivers which support Tx NIC multiqueue avoid driver global lock
> to be MP-scalable.  I'm worried about sc->sc_txlock might be required in
> ifp->if_transmit() driver implementation.

It does not currently impact the few drivers that use Tx multi-queue.  In my example, “sc_txlock” is really just a placeholder for “hardware has single Tx queue, and this is the mutex for it”.  My work here has no impact on the drivers that use the driver-specific ifp->if_transmit facility at this time, although I would like to harmonize them at some point so common sets of assertions and queue manipulation routines can be used.

-- thorpej