drm/i915: Add i915_gem_request_unreference__unlocked

We were missing a convenience stub to aquire the right mutex whilst
dropping the request, so add it.

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>

diff --git a/drivers/gpu/drm/i915/i915_drv.h b/drivers/gpu/drm/i915/i915_drv.h
index e326ac9..4ef320c 100644 (file)
--- a/drivers/gpu/drm/i915/i915_drv.h
+++ b/drivers/gpu/drm/i915/i915_drv.h
@@ -2142,6 +2142,19 @@ i915_gem_request_unreference(struct drm_i915_gem_request *req)
        kref_put(&req->ref, i915_gem_request_free);
 }
 
+static inline void
+i915_gem_request_unreference__unlocked(struct drm_i915_gem_request *req)
+{
+       if (req && !atomic_add_unless(&req->ref.refcount, -1, 1)) {
+               struct drm_device *dev = req->ring->dev;
+
+               mutex_lock(&dev->struct_mutex);
+               if (likely(atomic_dec_and_test(&req->ref.refcount)))
+                       i915_gem_request_free(&req->ref);
+               mutex_unlock(&dev->struct_mutex);
+       }
+}
+
 static inline void i915_gem_request_assign(struct drm_i915_gem_request **pdst,
                                           struct drm_i915_gem_request *src)
 {

diff --git a/drivers/gpu/drm/i915/i915_gem.c b/drivers/gpu/drm/i915/i915_gem.c
index d07c0b1..3a91365 100644 (file)
--- a/drivers/gpu/drm/i915/i915_gem.c
+++ b/drivers/gpu/drm/i915/i915_gem.c
@@ -2866,9 +2866,7 @@ i915_gem_wait_ioctl(struct drm_device *dev, void *data, struct drm_file *file)
        ret = __i915_wait_request(req, reset_counter, true,
                                  args->timeout_ns > 0 ? &args->timeout_ns : NULL,
                                  file->driver_priv);
-       mutex_lock(&dev->struct_mutex);
-       i915_gem_request_unreference(req);
-       mutex_unlock(&dev->struct_mutex);
+       i915_gem_request_unreference__unlocked(req);
        return ret;
 
 out:
@@ -4071,9 +4069,7 @@ i915_gem_ring_throttle(struct drm_device *dev, struct drm_file *file)
        if (ret == 0)
                queue_delayed_work(dev_priv->wq, &dev_priv->mm.retire_work, 0);
 
-       mutex_lock(&dev->struct_mutex);
-       i915_gem_request_unreference(target);
-       mutex_unlock(&dev->struct_mutex);
+       i915_gem_request_unreference__unlocked(target);
 
        return ret;
 }