drm/ttm: Use the hashtab _rcu interface for ttm_objects

Also move a kref_init() out of spinlocked region

Signed-off-by: Thomas Hellstrom <thellstrom@vmware.com>
Signed-off-by: Dave Airlie <airlied@redhat.com>

1 files changed, 14 insertions, 7 deletions

diff --git a/drivers/gpu/drm/ttm/ttm_object.c b/drivers/gpu/drm/ttm/ttm_object.c
index 0e13d9f059ff..58a5f3261c0b 100644
--- a/drivers/gpu/drm/ttm/ttm_object.c
+++ b/drivers/gpu/drm/ttm/ttm_object.c
@@ -157,11 +157,11 @@ int ttm_base_object_init(struct ttm_object_file *tfile,
         base->refcount_release = refcount_release;
         base->ref_obj_release = ref_obj_release;
         base->object_type = object_type;
-        spin_lock(&tdev->object_lock);
         kref_init(&base->refcount);
-        ret = drm_ht_just_insert_please(&tdev->object_hash,
-                                        &base->hash,
-                                        (unsigned long)base, 31, 0, 0);
+        spin_lock(&tdev->object_lock);
+        ret = drm_ht_just_insert_please_rcu(&tdev->object_hash,
+                                            &base->hash,
+                                            (unsigned long)base, 31, 0, 0);
         spin_unlock(&tdev->object_lock);
         if (unlikely(ret != 0))
                 goto out_err0;
@@ -175,7 +175,7 @@ int ttm_base_object_init(struct ttm_object_file *tfile,
         return 0;
 out_err1:
         spin_lock(&tdev->object_lock);
-        (void)drm_ht_remove_item(&tdev->object_hash, &base->hash);
+        (void)drm_ht_remove_item_rcu(&tdev->object_hash, &base->hash);
         spin_unlock(&tdev->object_lock);
 out_err0:
         return ret;
@@ -189,8 +189,15 @@ static void ttm_release_base(struct kref *kref)
         struct ttm_object_device *tdev = base->tfile->tdev;
 
         spin_lock(&tdev->object_lock);
-        (void)drm_ht_remove_item(&tdev->object_hash, &base->hash);
+        (void)drm_ht_remove_item_rcu(&tdev->object_hash, &base->hash);
         spin_unlock(&tdev->object_lock);
+
+        /*
+         * Note: We don't use synchronize_rcu() here because it's far
+         * too slow. It's up to the user to free the object using
+         * call_rcu() or ttm_base_object_kfree().
+         */
+
         if (base->refcount_release) {
                 ttm_object_file_unref(&base->tfile);
                 base->refcount_release(&base);
@@ -216,7 +223,7 @@ struct ttm_base_object *ttm_base_object_lookup(struct ttm_object_file *tfile,
         int ret;
 
         rcu_read_lock();
-        ret = drm_ht_find_item(&tdev->object_hash, key, &hash);
+        ret = drm_ht_find_item_rcu(&tdev->object_hash, key, &hash);
 
         if (likely(ret == 0)) {
                 base = drm_hash_entry(hash, struct ttm_base_object, hash);