drm/i915: Mark up i915_vma_unbind() as a potential sleeper
authorChris Wilson <chris@chris-wilson.co.uk>
Thu, 9 Nov 2017 21:34:50 +0000 (21:34 +0000)
committerChris Wilson <chris@chris-wilson.co.uk>
Thu, 9 Nov 2017 22:06:09 +0000 (22:06 +0000)
commit7f017b19fbce6200a993305425bf930f38fcd9e6
tree2ab755d2b104e8e3cf124940adf300a7dd494071
parent15e4cda950ea660837f6733426691c8e467010a6
drm/i915: Mark up i915_vma_unbind() as a potential sleeper

Whenever we want to unbind a vma, we must wait on all GPU activity to
complete first. (This is what gives us the ability to do fine grained
eviction and purging by only having to wait on the VMA that we need to
unbind to proceed; though if pushed we can make it a rule that we are
only allowed to unbind already idle VMA and move the burden of the work
and organising the sleep onto the caller.) Currently, we might only
sleep if the vma is still active on the GPU, but in principle
i915_vma_unbind() always implies a sleep, so mark it up with a
might_sleep().

Suggested-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
References: https://bugs.freedesktop.org/show_bug.cgi?id=103638
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Cc: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Cc: Matthew Auld <matthew.william.auld@gmail.com>
Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
Reviewed-by: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20171109213450.13875-2-chris@chris-wilson.co.uk
drivers/gpu/drm/i915/i915_vma.c