[Intel-gfx] [PATCH 2/6] drm/i915: make fbdev initialization asynchronous

[Chris Wilson]

On Thu, Mar 06, 2014 at 08:17:51AM -0800, Jesse Barnes wrote:
> On Thu, 6 Mar 2014 09:12:40 +0000
> Chris Wilson <chris at chris-wilson.co.uk> wrote:
> 
> > On Wed, Mar 05, 2014 at 02:48:27PM -0800, Jesse Barnes wrote:
> > > This gets us out of our init code and out to userspace quite a bit
> > > faster, but does open us up to some bugs given the state of our init
> > > time locking.
> > 
> > Why are we hand rolling an async task for this? See
> > http://lists.freedesktop.org/archives/intel-gfx/2010-August/007642.html
> > 
> > And the locking issue was the main reason why we haven't been able to
> > proceed so far...
> 
> In looking at the async domains it didn't appear that they would
> actually save me much if any code in most of these cases.

I agree that it may not save actual lines of code. I am more thinking of
the need to try and integrate with existing work along the same paths. I
presume that the async init debug code is more refined (or at least
could be) etc.
 
> The locking is worrisome, but I added some extra WARNs and things are
> solid across multiple boots, reloads, and suspend/resume cycles.  I
> haven't tried lockdep though...

Things have changed wrt locking, but I still expect that to make lockdep
happy will require some ugly reworking.
-Chris

-- 
Chris Wilson, Intel Open Source Technology Centre