[ofa-general] RE: [PATCH 1/4] [NET_SCHED] explict hold dev tx lock

[Waskiewicz Jr, Peter P]

> The one thing that seems obvious is to use 
> dev->hard_prep_xmit() in the patches i posted to select the 
> xmit ring. You should be able to do figure out the txmit ring 
> without holding any lock. 

I've looked at that as a candidate to use.  The lock for enqueue would
be needed when actually placing the skb into the appropriate software
queue for the qdisc, so it'd be quick.

> I lost track of how/where things went since the last 
> discussion; so i need to wrap my mind around it to make 
> sensisble suggestions - I know the core patches are in the 
> kernel but havent paid attention to details and if you look 
> at my second patch youd see a comment in
> dev_batch_xmit() which says i need to scrutinize multiqueue more. 

No worries.  I'll try to get things together on my end and provide some
patches to add a per-queue lock.  In the meantime, I'll take a much
closer look at the batching code, since I've stopped looking at the
patches in-depth about a month ago.  :-(

Thanks,
-PJ Waskiewicz