X-Git-Url: https://git.camperquake.de/gitweb.cgi?a=blobdiff_plain;f=module%2Fzfs%2Frefcount.c;h=a6155460625a477206c3b6aae5a2d9894de4ce6b;hb=d4ed667343c3dac114642b9f6cb4f7baa3ff7334;hp=8358b4ceeb0cdfd268591763346f37c3a6af200b;hpb=428870ff734fdaccc342b33fc53cf94724409a46;p=zfs.git

diff --git a/module/zfs/refcount.c b/module/zfs/refcount.c
index 8358b4c..a615546 100644
--- a/module/zfs/refcount.c
+++ b/module/zfs/refcount.c
@@ -25,7 +25,7 @@
 #include <sys/zfs_context.h>
 #include <sys/refcount.h>
 
-#if defined(DEBUG) || !defined(_KERNEL)
+#ifdef	ZFS_DEBUG
 
 #ifdef _KERNEL
 int reference_tracking_enable = FALSE; /* runs out of memory too easily */
@@ -72,13 +72,13 @@ refcount_destroy_many(refcount_t *rc, uint64_t number)
 	reference_t *ref;
 
 	ASSERT(rc->rc_count == number);
-	while (ref = list_head(&rc->rc_list)) {
+	while ((ref = list_head(&rc->rc_list))) {
 		list_remove(&rc->rc_list, ref);
 		kmem_cache_free(reference_cache, ref);
 	}
 	list_destroy(&rc->rc_list);
 
-	while (ref = list_head(&rc->rc_removed)) {
+	while ((ref = list_head(&rc->rc_removed))) {
 		list_remove(&rc->rc_removed, ref);
 		kmem_cache_free(reference_history_cache, ref->ref_removed);
 		kmem_cache_free(reference_cache, ref);
@@ -110,7 +110,7 @@ refcount_count(refcount_t *rc)
 int64_t
 refcount_add_many(refcount_t *rc, uint64_t number, void *holder)
 {
-	reference_t *ref;
+	reference_t *ref = NULL;
 	int64_t count;
 
 	if (reference_tracking_enable) {
@@ -189,4 +189,35 @@ refcount_remove(refcount_t *rc, void *holder)
 	return (refcount_remove_many(rc, 1, holder));
 }
 
-#endif
+void
+refcount_transfer(refcount_t *dst, refcount_t *src)
+{
+	int64_t count, removed_count;
+	list_t list, removed;
+
+	list_create(&list, sizeof (reference_t),
+	    offsetof(reference_t, ref_link));
+	list_create(&removed, sizeof (reference_t),
+	    offsetof(reference_t, ref_link));
+
+	mutex_enter(&src->rc_mtx);
+	count = src->rc_count;
+	removed_count = src->rc_removed_count;
+	src->rc_count = 0;
+	src->rc_removed_count = 0;
+	list_move_tail(&list, &src->rc_list);
+	list_move_tail(&removed, &src->rc_removed);
+	mutex_exit(&src->rc_mtx);
+
+	mutex_enter(&dst->rc_mtx);
+	dst->rc_count += count;
+	dst->rc_removed_count += removed_count;
+	list_move_tail(&dst->rc_list, &list);
+	list_move_tail(&dst->rc_removed, &removed);
+	mutex_exit(&dst->rc_mtx);
+
+	list_destroy(&list);
+	list_destroy(&removed);
+}
+
+#endif	/* ZFS_DEBUG */