[Intel-gfx] [PATCH 2/2] drm/i915: Disable page-faults around the fast pwrite/pread paths

[Chris Wilson]

On Sat, 09 Jul 2011 14:06:23 -0700, Keith Packard <keithp at keithp.com> wrote:
> On Sat, 09 Jul 2011 21:50:26 +0100, Chris Wilson <chris at chris-wilson.co.uk> wrote:
> Sure, it's permitted, so ideally we'd detect this abuse and fall back to
> the slow path, but we need a cheap check which takes the slow path,
> perhaps pessimistically.

If we prefault every page, then we only hit the slow path under system
load combined or severe memory pressure. I don't think that is too bad a
compromise.

I can stick some counters in there and find out what the impact actually
is.
-Chris

-- 
Chris Wilson, Intel Open Source Technology Centre