Re: [PATCH 1/2] drm/i915: reorganize the unclaimed register detection code

Daniel Vetter
2014-08-26T14:08:13Z

On Tue, Aug 26, 2014 at 02:46:25PM +0100, Chris Wilson wrote:
> On Tue, Aug 26, 2014 at 03:34:07PM +0200, Daniel Vetter wrote:
> > On Tue, Aug 26, 2014 at 10:29:23AM -0300, Paulo Zanoni wrote:
> > > 2014-08-26 10:18 GMT-03:00 Chris Wilson <chris@chris-wilson.co.uk>:
> > > > On Tue, Aug 26, 2014 at 10:04:22AM -0300, Paulo Zanoni wrote:
> > > >> Of course, we can also implement the one-shot thing on top of the
> > > >> above, but it won't really help us reducing the amount of reads on the
> > > >> "happy case" where we never got the error before.
> > > >
> > > > Actually I am tempted to dynamically patch the mmio vfuncs to avoid even
> > > > the forcewake spinlock when we already hold it. So there won't be any
> > > > such logic except when enabled by the user.
> > >
> > > Should I expect a patch from you, or should I go and write the patch
> > > based on what we already discussed?
> >
> > Imo this is crazy - we have no control over what the compiler does and
> > when exactly it loads vtable entries, so patching them at runtime would be
> > an interesting excercise at best.
>
> Wtf?

I've assumed you'd runtime patch the vtables or something like that. And I
didn't see any other less crazy way to ...
-Daniel
--
Daniel Vetter
Software Engineer, Intel Corporation
+41 (0) 79 365 57 48 - http://blog.ffwll.ch