diff --git a/drivers/gpu/drm/i915/i915_gem.c b/drivers/gpu/drm/i915/i915_gem.c index 71b5129947ba6a82856a86a92b95e3e7d8c86eb7..b0016bb656311a2126c3c7f7f0a7e26a231671f0 100644 --- a/drivers/gpu/drm/i915/i915_gem.c +++ b/drivers/gpu/drm/i915/i915_gem.c @@ -4342,6 +4342,19 @@ void i915_gem_release(struct drm_device *dev, struct drm_file *file) spin_unlock(&file_priv->mm.lock); } +static bool mutex_is_locked_by(struct mutex *mutex, struct task_struct *task) +{ + if (!mutex_is_locked(mutex)) + return false; + +#if defined(CONFIG_SMP) || defined(CONFIG_DEBUG_MUTEXES) + return mutex->owner == task; +#else + /* Since UP may be pre-empted, we cannot assume that we own the lock */ + return false; +#endif +} + static int i915_gem_inactive_shrink(struct shrinker *shrinker, struct shrink_control *sc) { @@ -4352,10 +4365,15 @@ i915_gem_inactive_shrink(struct shrinker *shrinker, struct shrink_control *sc) struct drm_device *dev = dev_priv->dev; struct drm_i915_gem_object *obj; int nr_to_scan = sc->nr_to_scan; + bool unlock = true; int cnt; - if (!mutex_trylock(&dev->struct_mutex)) - return 0; + if (!mutex_trylock(&dev->struct_mutex)) { + if (!mutex_is_locked_by(&dev->struct_mutex, current)) + return 0; + + unlock = false; + } if (nr_to_scan) { nr_to_scan -= i915_gem_purge(dev_priv, nr_to_scan); @@ -4371,6 +4389,7 @@ i915_gem_inactive_shrink(struct shrinker *shrinker, struct shrink_control *sc) if (obj->pin_count == 0 && obj->pages_pin_count == 0) cnt += obj->base.size >> PAGE_SHIFT; - mutex_unlock(&dev->struct_mutex); + if (unlock) + mutex_unlock(&dev->struct_mutex); return cnt; }