[ofa-general] Re: [RFC/PATCH] mthca: ensure alignment of doorbell writes

[akepner at sgi.com]

On Fri, Aug 03, 2007 at 10:55:09AM -0700, Roland Dreier wrote:

> Looking at this further... does mlx4 need the same treatment for
> writing CQ doorbells?

Yes, looks like the same deal there. (I don't have any 
mlx4 h/w, so didn't check that.)

> 
> How about libmthca/libmlx4 in userspace?
> 

Yes and yes. What do you think about using the new 
"doorbell type" that was in the patch that started 
this thread? For mthca it was defined like this:

union mthca_doorbell {
	__be64 val64;
	__be32 val32[2];
};

Or should we just add __attribute__ ((aligned(8))) to 
all the "__be32 doorbell[2]", etc. definitions?

-- 
Arthur