Re: Opinion on ordering of writel vs. stores to RAM

[Jesse Barnes]

On Saturday, September 09, 2006 3:08 am, David Miller wrote:
> From: Jeff Garzik <jeff@xxxxxxxxxx>
> Date: Sat, 09 Sep 2006 05:55:19 -0400
>
> > As (I think) BenH mentioned in another email, the normal way Linux
> > handles these interfaces is for the primary API (readX, writeX) to
> > be strongly ordered, strongly coherent, etc.  And then there is a
> > relaxed version without barriers and syncs, for the smart guys who
> > know what they're doing
>
> Indeed, I think that is the way to handle this.

Well why didn't you guys mention this when mmiowb() went in?

I agree that having a relaxed PIO ordering version of writeX makes sense 
(jejb convinced me of this on irc the other day).  But what to name it?  
We already have readX_relaxed, but that's for PIO vs. DMA ordering, not 
PIO vs. PIO.  To distinguish from that case maybe writeX_weak or 
writeX_nobarrier would make sense?

Jesse
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