drm/i915: Prevent lock-cycles between GPU waits and GPU resets
authorChris Wilson <chris@chris-wilson.co.uk>
Wed, 12 Jun 2019 08:52:46 +0000 (09:52 +0100)
committerChris Wilson <chris@chris-wilson.co.uk>
Wed, 12 Jun 2019 11:06:11 +0000 (12:06 +0100)
commit33df8a7697a08ec96811a1e9bbce45c7cdbbc316
tree68c4739164b54339de55ee5bb7f3a480f97c953a
parentea60f4bdc4330fc3be90e6a8634b9b912046b09d
drm/i915: Prevent lock-cycles between GPU waits and GPU resets

We cannot allow ourselves to wait on the GPU while holding any lock as we
may need to reset the GPU. While there is not an explicit lock between
the two operations, lockdep cannot detect the dependency. So let's tell
lockdep about the wait/reset dependency with an explicit lockmap.

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Mika Kuoppala <mika.kuoppala@linux.intel.com>
Cc: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Reviewed-by: Mika Kuoppala <mika.kuoppala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20190612085246.16374-1-chris@chris-wilson.co.uk
drivers/gpu/drm/i915/gt/intel_reset.c
drivers/gpu/drm/i915/i915_drv.h
drivers/gpu/drm/i915/i915_gem.c
drivers/gpu/drm/i915/i915_request.c
drivers/gpu/drm/i915/selftests/mock_gem_device.c