> -----Original Message----- > From: intel-gfx-bounces@xxxxxxxxxxxxxxxxxxxxx [mailto:intel-gfx- > bounces@xxxxxxxxxxxxxxxxxxxxx] On Behalf Of Chris Wilson > Sent: Monday, January 20, 2014 10:18 AM > To: intel-gfx@xxxxxxxxxxxxxxxxxxxxx > Subject: [PATCH 1/2] drm/i915: Wait for completion of pending > flips when starved of fences > > On older generations (gen2, gen3) the GPU requires fences for many > operations, such as blits. The display hardware also requires fences for > scanouts and this leads to a situation where an arbitrary number of fences > may be pinned by old scanouts following a pageflip but before we have > executed the unpin workqueue. This is unpredictable by userspace and leads > to random EDEADLK when submitting an otherwise benign execbuffer. > However, we can detect when we have an outstanding flip and so cause > userspace to wait upon their completion before finally declaring that the > system is starved of fences. This is really no worse than forcing the GPU to > stall waiting for older execbuffer to retire and release their fences before we > can reallocate them for the next execbuffer. > > v2: move the test for a pending fb unpin to a common routine for later reuse > during eviction > > Reported-and-tested-by: dimon@xxxxxxx > Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=73696 > Signed-off-by: Chris Wilson <chris@xxxxxxxxxxxxxxxxxx> Review-by: Jon Bloomfield <jon.bloomfield@xxxxxxxxx> _______________________________________________ Intel-gfx mailing list Intel-gfx@xxxxxxxxxxxxxxxxxxxxx http://lists.freedesktop.org/mailman/listinfo/intel-gfx
