Subject: Re: [PATCH] irq: Add node_affinity CPU masks for smarter irqbalance hints

From: Andi Kleen <[email-masked]>
Date: Tue, 24 Nov 2009 21:35:41 +0100

Eric Dumazet <[email-masked]> writes:

> David Miller a écrit :
>> From: Eric Dumazet <[email-masked]>
>> Date: Tue, 24 Nov 2009 19:26:15 +0100
>> 
>>> It seems complex to me, maybe optimal thing would be to use a NUMA policy to
>>> spread vmalloc() allocations to all nodes to get a good bandwidth...
>> 
>> vmalloc() and sk_buff's don't currently mix and I really don't see us
>> every allowing them to :-)
>
> I think Peter was referring to tx/rx rings buffers, not sk_buffs.
>
> They (ring buffers) are allocated with vmalloc() at driver init time.

They are typically allocated with dma_alloc_coherent(), which does
allocate a continuous area.  In theory you could do interleaving
with IOMMus, but just putting it on the same node as the device
is probably better.

-Andi
-- 
[email-masked] -- Speaking for myself only.