Re: [PATCH] drm/i915: Skip fence installation for objects with rotated views (v3)

Tvrtko Ursulin
2015-10-29T13:33:37Z

On 29/10/15 13:20, Ville Syrjälä wrote:
> On Wed, Oct 28, 2015 at 06:24:19PM -0700, Vivek Kasireddy wrote:
>> While pinning a fb object to the display plane, only install a fence
>> if the object is using a normal view. This corresponds with the
>> behavior found in i915_gem_object_do_pin() where the fencability
>> criteria is determined only for objects with normal views.
>>
>> v2:
>> Look at the object's map_and_fenceable flag to determine whether to
>> install a fence or not (Chris).
>>
>> v3:
>> Pin and unpin a fence only if the current view type is normal.
>>
>> Cc: Chris Wilson <chris@chris-wilson.co.uk>
>> Cc: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
>> Cc: Ville Syrjala <ville.syrjala@linux.intel.com>
>> Signed-off-by: Vivek Kasireddy <vivek.kasireddy@intel.com>
>> ---
>> drivers/gpu/drm/i915/intel_display.c | 7 +++++--
>> 1 file changed, 5 insertions(+), 2 deletions(-)
>>
>> diff --git a/drivers/gpu/drm/i915/intel_display.c b/drivers/gpu/drm/i915/intel_display.c
>> index 2fdfca1..ac06f8c 100644
>> --- a/drivers/gpu/drm/i915/intel_display.c
>> +++ b/drivers/gpu/drm/i915/intel_display.c
>> @@ -2419,7 +2419,8 @@ intel_pin_and_fence_fb_obj(struct drm_plane *plane,
>> * framebuffer compression. For simplicity, we always install
>> * a fence as the cost is not that onerous.
>> */
>> - ret = i915_gem_object_get_fence(obj);
>> + if (view.type == I915_GGTT_VIEW_NORMAL)
>> + ret = i915_gem_object_get_fence(obj);
>
> Missing the same check for the pin_fence().

Well spotted. :(

So a fence leak and another testcase needed to exercise it.

Pin normal, then pin rotated, unpin both = leak one fence. Repeat
num_fences times until no more fences and fail?

Regards,

Tvrtko