drm/i915: Allow kswapd to pause the device whilst reaping
authorChris Wilson <chris@chris-wilson.co.uk>
Thu, 1 Jun 2017 13:33:29 +0000 (14:33 +0100)
committerChris Wilson <chris@chris-wilson.co.uk>
Fri, 2 Jun 2017 13:54:27 +0000 (14:54 +0100)
commit1d24ad457c54f0c8a835c33b7f687c454b643fcb
tree362442f8e81480ded54045400c174d35396f23ae
parentff8f797557c73f1f191866a013b61a7286330021
drm/i915: Allow kswapd to pause the device whilst reaping

In commit 5763ff04dc4e ("drm/i915: Avoid GPU stalls from kswapd") we
stopped direct reclaim and kswapd from triggering GPU/client stalls
whilst running (by restricting the objects they could reap to be idle).

However with abusive GPU usage, it becomes quite easy to starve kswapd
of memory and prevent it from making forward progress towards obtaining
enough free memory (thus driving the system closer to swap exhaustion).
Relax the previous restriction to allow kswapd (but not direct reclaim)
to stall the device whilst reaping purgeable pages.

v2: Also acquire the rpm wakelock to allow kswapd to unbind buffers.

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/20170601133331.5973-1-chris@chris-wilson.co.uk
Reviewed-by: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Reviewed-by: Mika Kuoppala <mika.kuoppala@intel.com>
drivers/gpu/drm/i915/i915_gem_shrinker.c