[ofa-general] Re: [PATCH 2/3][NET_BATCH] net core use batching

[Stephen Hemminger]

On Fri, 12 Oct 2007 09:08:58 -0700
"Brandeburg, Jesse" <jesse.brandeburg at intel.com> wrote:

> Andi Kleen wrote:
> >> When the hw TX queue gains space, the driver self-batches packets
> >> from the sw queue to the hw queue.
> > 
> > I don't really see the advantage over the qdisc in that scheme.
> > It's certainly not simpler and probably more code and would likely
> > also not require less locks (e.g. a currently lockless driver
> > would need a new lock for its sw queue). Also it is unclear to me
> > it would be really any faster.
> 
> related to this comment, does Linux have a lockless (using atomics)
> singly linked list element?  That would be very useful in a driver hot
> path.

Use RCU? or write a generic version and get it reviewed.  You really
want someone with knowledge of all the possible barrier impacts to
review it.

-- 
Stephen Hemminger <shemminger at linux-foundation.org>