Now that we've eliminated a lot of uses of ring->default_context,
we can eliminate the pointer itself.
All the engines share the same default intel_context, so we can just
keep a single reference to it in the dev_priv structure rather than one
in each of the engine[] elements. This make refcounting more sensible
too, as we now have a refcount of one for the one pointer, rather than
a refcount of one but multiple pointers.
From an idea by Chris Wilson.
v2: transform an extra instance of ring->default_context introduced by
42f1cae8c drm/i915: Restore inhibiting the load of the default context
That patch's commentary includes:
v2: Mark the global default context as uninitialized on GPU reset so
that the context-local workarounds are reloaded upon re-enabling
The code implementing that now also benefits from the replacement of
the multiple (per-ring) pointers to the default context with a single
pointer to the unique kernel context.
v4: Rebased, remove underused local (Nick Hoath)
Signed-off-by: Dave Gordon <david.s.gordon@intel.com>
Reviewed-by: Nick Hoath <nicholas.hoath@intel.com>
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Link: http://patchwork.freedesktop.org/patch/msgid/1453230175-19330-3-git-send-email-david.s.gordon@intel.com
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
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