diff options
author | Chris Wilson <chris@chris-wilson.co.uk> | 2016-08-05 10:14:21 +0100 |
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committer | Chris Wilson <chris@chris-wilson.co.uk> | 2016-08-05 10:54:42 +0100 |
commit | 9ad3676148511d6af72be6f3638e361fd86e1f7b (patch) | |
tree | c7e32698c73443ae1de563d0d342e121b910c4c4 /drivers/gpu/drm/i915/intel_ringbuffer.c | |
parent | e883d73503205d1eaaf049b835bf135b46738f57 (diff) |
drm/i915: Remove locking for get_tiling
Since we are not concerned with userspace racing itself with set-tiling
(the order is indeterminant even if we take a lock), then we can safely
read back the single obj->tiling_mode and do the static lookup of
swizzle mode without having to take a lock.
get-tiling is reasonably frequent due to the back-channel passing around
of tiling parameters in DRI2/DRI3.
v2: Make tiling_mode a full unsigned int so that we can trivially use it
with READ_ONCE(). Separating it out into manual control over the flags
field was too noisy for a simple patch. Note that we could use the lower
bits of obj->stride for the tiling mode.
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1470388464-28458-16-git-send-email-chris@chris-wilson.co.uk
Diffstat (limited to 'drivers/gpu/drm/i915/intel_ringbuffer.c')
0 files changed, 0 insertions, 0 deletions