1 files changed, 43 insertions, 16 deletions

diff --git a/drivers/gpu/drm/i915/i915_active.c b/drivers/gpu/drm/i915/i915_active.c
index 215b6ff8aa73..863ae12707ba 100644
--- a/drivers/gpu/drm/i915/i915_active.c
+++ b/drivers/gpu/drm/i915/i915_active.c
@@ -6,6 +6,7 @@
 
 #include "i915_drv.h"
 #include "i915_active.h"
+#include "i915_globals.h"
 
 #define BKL(ref) (&(ref)->i915->drm.struct_mutex)
 
@@ -17,6 +18,7 @@
  * nodes from a local slab cache to hopefully reduce the fragmentation.
  */
 static struct i915_global_active {
+	struct i915_global base;
 	struct kmem_cache *slab_cache;
 } global;
 
@@ -163,17 +165,25 @@ int i915_active_ref(struct i915_active *ref,
 		    struct i915_request *rq)
 {
 	struct i915_active_request *active;
+	int err = 0;
+
+	/* Prevent reaping in case we malloc/wait while building the tree */
+	i915_active_acquire(ref);
 
 	active = active_instance(ref, timeline);
-	if (IS_ERR(active))
-		return PTR_ERR(active);
+	if (IS_ERR(active)) {
+		err = PTR_ERR(active);
+		goto out;
+	}
 
 	if (!i915_active_request_isset(active))
 		ref->count++;
 	__i915_active_request_set(active, rq);
 
 	GEM_BUG_ON(!ref->count);
-	return 0;
+out:
+	i915_active_release(ref);
+	return err;
 }
 
 bool i915_active_acquire(struct i915_active *ref)
@@ -223,19 +233,25 @@ int i915_request_await_active_request(struct i915_request *rq,
 int i915_request_await_active(struct i915_request *rq, struct i915_active *ref)
 {
 	struct active_node *it, *n;
-	int ret;
+	int err = 0;
 
-	ret = i915_request_await_active_request(rq, &ref->last);
-	if (ret)
-		return ret;
+	/* await allocates and so we need to avoid hitting the shrinker */
+	if (i915_active_acquire(ref))
+		goto out; /* was idle */
+
+	err = i915_request_await_active_request(rq, &ref->last);
+	if (err)
+		goto out;
 
 	rbtree_postorder_for_each_entry_safe(it, n, &ref->tree, node) {
-		ret = i915_request_await_active_request(rq, &it->base);
-		if (ret)
-			return ret;
+		err = i915_request_await_active_request(rq, &it->base);
+		if (err)
+			goto out;
 	}
 
-	return 0;
+out:
+	i915_active_release(ref);
+	return err;
 }
 
 #if IS_ENABLED(CONFIG_DRM_I915_DEBUG_GEM)
@@ -271,16 +287,27 @@ void i915_active_retire_noop(struct i915_active_request *active,
 #include "selftests/i915_active.c"
 #endif
 
+static void i915_global_active_shrink(void)
+{
+	kmem_cache_shrink(global.slab_cache);
+}
+
+static void i915_global_active_exit(void)
+{
+	kmem_cache_destroy(global.slab_cache);
+}
+
+static struct i915_global_active global = { {
+	.shrink = i915_global_active_shrink,
+	.exit = i915_global_active_exit,
+} };
+
 int __init i915_global_active_init(void)
 {
 	global.slab_cache = KMEM_CACHE(active_node, SLAB_HWCACHE_ALIGN);
 	if (!global.slab_cache)
 		return -ENOMEM;
 
+	i915_global_register(&global.base);
 	return 0;
 }
-
-void __exit i915_global_active_exit(void)
-{
-	kmem_cache_destroy(global.slab_cache);
-}