drm/ttm: Use the hashtab _rcu interface for ttm_objects
authorThomas Hellstrom <thellstrom@vmware.com>
Tue, 20 Nov 2012 12:16:51 +0000 (12:16 +0000)
committerDave Airlie <airlied@redhat.com>
Wed, 28 Nov 2012 08:36:15 +0000 (18:36 +1000)
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>
drivers/gpu/drm/ttm/ttm_object.c

index 0e13d9f059ffde25adb61dea3ca52cee8f38e92e..58a5f3261c0b083f026087f8722bf6e6915ea25f 100644 (file)
@@ -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);