From mboxrd@z Thu Jan  1 00:00:00 1970
From: Ben Widawsky <ben@bwidawsk.net>
Subject: Re: [PATCH] [RFC] drm/i915: read-read semaphore
	optimization
Date: Tue, 13 Dec 2011 14:49:49 -0800
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To: Keith Packard <keithp@keithp.com>
Cc: Daniel Vetter <daniel.vetter@ffwll.ch>, intel-gfx@lists.freedesktop.org
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On 12/13/2011 08:36 AM, Keith Packard wrote:
> On Tue, 13 Dec 2011 17:01:33 +0100, Daniel Vetter <daniel@ffwll.ch> wrote:
> 
>> - or remove it all and invalidate/flush unconditionally.
> 
> Eric and I were chatting yesterday about trying this -- it seems like
> we'd be able to dramatically simplify the kernel module by doing this,
> and given how much flushing already occurs, I doubt we'd see any
> significant performance difference, and we'd save a pile of CPU time,
> which might actually improve performance.


Would we want to keep domain tracking if the HW worked correctly and we
didn't have to always flush. It seems like a shame to just gut the code
if it actually could offer a benefit on future generations.

I know Daniel has the same idea about gutting it...

Ben