drm/i915: i915_gem_shrink_all() needs an awake device

Since to unbind an object, we may need a powered up device to access the
GTT entries, we only shrink bound objects if awake. Callers to
i915_gem_shrink_all() had to take this into account and take the rpm
wakeref, but we can move this wakeref into the shrink_all itself for
convenience and making the function live up to its name.
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Link: http://patchwork.freedesktop.org/patch/msgid/20170208104710.18089-1-chris@chris-wilson.co.ukReviewed-by: Mika Kuoppala <mika.kuoppala@intel.com>

drivers/gpu/drm/i915/i915_gem.c

@@ -4648,14 +4648,10 @@ void i915_gem_load_cleanup(struct drm_i915_private *dev_priv)
 
 int i915_gem_freeze(struct drm_i915_private *dev_priv)
 {
-	intel_runtime_pm_get(dev_priv);
-
 	mutex_lock(&dev_priv->drm.struct_mutex);
 	i915_gem_shrink_all(dev_priv);
 	mutex_unlock(&dev_priv->drm.struct_mutex);
 
-	intel_runtime_pm_put(dev_priv);
-
 	return 0;
 }
 

drivers/gpu/drm/i915/i915_gem_shrinker.c

@@ -259,10 +259,13 @@ unsigned long i915_gem_shrink_all(struct drm_i915_private *dev_priv)
 {
 	unsigned long freed;
 
+	intel_runtime_pm_get(dev_priv);
 	freed = i915_gem_shrink(dev_priv, -1UL,
 				I915_SHRINK_BOUND |
 				I915_SHRINK_UNBOUND |
 				I915_SHRINK_ACTIVE);
+	intel_runtime_pm_put(dev_priv);
+
 	rcu_barrier(); /* wait until our RCU delayed slab frees are completed */
 
 	return freed;
@@ -380,9 +383,7 @@ i915_gem_shrinker_oom(struct notifier_block *nb, unsigned long event, void *ptr)
 	if (!i915_gem_shrinker_lock_uninterruptible(dev_priv, &slu, 5000))
 		return NOTIFY_DONE;
 
-	intel_runtime_pm_get(dev_priv);
 	freed_pages = i915_gem_shrink_all(dev_priv);
-	intel_runtime_pm_put(dev_priv);
 
 	/* Because we may be allocating inside our own driver, we cannot
 	 * assert that there are no objects with pinned pages that are not