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Re: rbuf starvation in the iwn driver

On Wed, Apr 07, 2010 at 11:30:24AM -0600, Sverre Froyen wrote:
> I've been looking at the iwn_rx_done code to see how I can fix this. One 
> option 
> is to use the code from iwn_rx_intr in if_iwn.c rev 1.32 (I presume I can 
> figure out the needed bus_dmamap changes by looking at if_nfe.c).
> However, it looks like the current OpenBSD and FreeBSD drivers do not use 
> private storage. FreeBSD just gets an mbuf cluster from m_getjcl and OpenBSD 
> uses MCLGETI. Is this an option for NetBSD? Why was private storage used in 
> the first place? For speed reasons?

No idea.

> Damien Bergamini warned me there would 
> likely be alignment issues.

If you use mbuf clusters, the storage will be aligned to 2k (size of
a mbuf cluster storage). I don't think it can be an issue.

Manuel Bouyer <>
     NetBSD: 26 ans d'experience feront toujours la difference

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