The current attempted split between xe/i915 vs. display
for intel_frontbuffer is a mess:
- the i915 rcu leaks through the interface to the display side
- the obj->frontbuffer write-side is now protected by a display
specific spinlock even though the actual obj->framebuffer
pointer lives in a i915 specific structure
- the kref is getting poked directly from both sides
- i915_active is still on the display side
Clean up the mess by moving everything about the frontbuffer
lifetime management to the i915/xe side:
- the rcu usage is now completely contained in i915
- frontbuffer_lock is moved into i915
- kref is on the i915/xe side (xe needs the refcount as well
due to intel_frontbuffer_queue_flush()->intel_frontbuffer_ref())
- the bo (and its refcounting) is no longer on the display side
- i915_active is contained in i915
I was pondering whether we could do this in some kind of smaller
steps, and perhaps we could, but it would probably have to start
with a bunch of reverts (which for sure won't go cleanly anymore).
So not convinced it's worth the hassle.
Acked-by: Jani Nikula <jani.nikula@intel.com>
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: https://patch.msgid.link/20251016185408.22735-10-ville.syrjala@linux.intel.com
Currently xe's intel_frontbuffer implementation forgets to
hold a reference on the bo. This makes the entire thing
extremely fragile as the cleanup order now depends on bo
references held by other things
(namely intel_fb_bo_framebuffer_fini()).
Move the bo refcounting to intel_frontbuffer_{get,release}()
so that both i915 and xe do this the same way.
I first tried to fix this by having xe do the refcounting
from its intel_bo_set_frontbuffer() implementation
(which is what i915 does currently), but turns out xe's
drm_gem_object_free() can sleep and thus drm_gem_object_put()
isn't safe to call while we hold fb_tracking.lock.
Fixes: 10690b8a49 ("drm/i915/display: Add intel_fb_bo_framebuffer_fini")
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20251003145734.7634-2-ville.syrjala@linux.intel.com
Reviewed-by: Jani Nikula <jani.nikula@intel.com>
As the first step towards making struct intel_display an opaque pointer
in i915 and xe drivers, convert the struct drm_i915_private and struct
xe_device display members into pointers.
Initially, add temporary struct intel_display __display members, and
point display at it to avoid dynamic allocation. In the future, we can
drop this, and switch to dynamic allocation.
The conversion is done simply with sed:
sed -i 's/&\([a-zA-Z0-9_>.-]*\)\(dev_priv\|i915\|xe\)->display\([^.]\)/\1\2->display\3/g' \
$(git ls-files -- drivers/gpu/drm/i915 drivers/gpu/drm/xe)
sed -i 's/\(dev_priv\|i915\|xe\)->display\./\1->display->/g' \
$(git ls-files -- drivers/gpu/drm/i915 drivers/gpu/drm/xe)
With a couple of manual tweaks on top.
v2: Initialize i915->display also in selftest mock_gem_device()
Reviewed-by: Gustavo Sousa <gustavo.sousa@intel.com>
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
Link: https://lore.kernel.org/r/20250507152254.2398934-1-jani.nikula@intel.com
Split out frontbuffer related declarations and static inlines from
gem/i915_gem_object.h into new gem/i915_gem_object_frontbuffer.h.
The main goal is to reduce header interdependencies. With
gem/i915_gem_object.h including display/intel_frontbuffer.h,
modification of the latter causes a whopping 300+ objects to be rebuilt,
while many of the source files actually needing it aren't explicitly
including it at all.
After the change, only 21 objects depend on display/intel_frontbuffer.h,
directly or indirectly.
Cc: Jouni Högander <jouni.hogander@intel.com>
Reviewed-by: Jouni Högander <jouni.hogander@intel.com>
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20230830085127.2416842-1-jani.nikula@intel.com
