drm/i915: Remove (struct_mutex) locking for busy-ioctl
authorChris Wilson <chris@chris-wilson.co.uk>
Fri, 5 Aug 2016 09:14:18 +0000 (10:14 +0100)
committerChris Wilson <chris@chris-wilson.co.uk>
Fri, 5 Aug 2016 09:54:40 +0000 (10:54 +0100)
commit3fdc13c7a3cbd5788daad4cf1ddc619856e2f1c0
treef7997345d3475a10541ed0806f41fb971589e98e
parent033d549b811ea8512efd57fa5fb5c53e498e0db3
drm/i915: Remove (struct_mutex) locking for busy-ioctl

By applying the same logic as for wait-ioctl, we can query whether a
request has completed without holding struct_mutex. The biggest impact
system-wide is removing the flush_active and the contention that causes.

Testcase: igt/gem_busy
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Akash Goel <akash.goel@intel.com>
Reviewed-by: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1470388464-28458-13-git-send-email-chris@chris-wilson.co.uk
drivers/gpu/drm/i915/i915_gem.c