diff options
author | Chris Wilson <chris@chris-wilson.co.uk> | 2017-07-18 14:41:24 +0100 |
---|---|---|
committer | Chris Wilson <chris@chris-wilson.co.uk> | 2017-07-19 13:19:24 +0100 |
commit | 3b19f16a556446c144a1f921444931b0cf9447ab (patch) | |
tree | cffdfd025ad7022405dad16291684d84ac9185da /drivers/gpu/drm/i915/i915_drv.h | |
parent | 023f807989f4d6a076258f4efe6d1da0d7aaeb29 (diff) |
drm/i915: Drain the device workqueue on unload
Workers on the i915->wq may rearm themselves so for completeness we need
to replace our flush_workqueue() with a call to drain_workqueue() before
unloading the device.
v2: Reinforce the drain_workqueue with an preceding rcu_barrier() as a
few of the tasks that need to be drained may first be armed by RCU.
References: https://bugs.freedesktop.org/show_bug.cgi?id=101627
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Matthew Auld <matthew.auld@intel.com>
Cc: Mika Kuoppala <mika.kuoppala@linux.intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/20170718134124.14832-1-chris@chris-wilson.co.uk
Reviewed-by: Mika Kuoppala <mika.kuoppala@linux.intel.com>
Diffstat (limited to 'drivers/gpu/drm/i915/i915_drv.h')
-rw-r--r-- | drivers/gpu/drm/i915/i915_drv.h | 20 |
1 files changed, 20 insertions, 0 deletions
diff --git a/drivers/gpu/drm/i915/i915_drv.h b/drivers/gpu/drm/i915/i915_drv.h index 559fdc7bb393..017361833c58 100644 --- a/drivers/gpu/drm/i915/i915_drv.h +++ b/drivers/gpu/drm/i915/i915_drv.h @@ -3300,6 +3300,26 @@ static inline void i915_gem_drain_freed_objects(struct drm_i915_private *i915) } while (flush_work(&i915->mm.free_work)); } +static inline void i915_gem_drain_workqueue(struct drm_i915_private *i915) +{ + /* + * Similar to objects above (see i915_gem_drain_freed-objects), in + * general we have workers that are armed by RCU and then rearm + * themselves in their callbacks. To be paranoid, we need to + * drain the workqueue a second time after waiting for the RCU + * grace period so that we catch work queued via RCU from the first + * pass. As neither drain_workqueue() nor flush_workqueue() report + * a result, we make an assumption that we only don't require more + * than 2 passes to catch all recursive RCU delayed work. + * + */ + int pass = 2; + do { + rcu_barrier(); + drain_workqueue(i915->wq); + } while (--pass); +} + struct i915_vma * __must_check i915_gem_object_ggtt_pin(struct drm_i915_gem_object *obj, const struct i915_ggtt_view *view, |