MINOR: mt_lists: Give MT_LIST_ADD, MT_LIST_ADDQ and MT_LIST_DEL a return value.
Make it so MT_LIST_ADD and MT_LIST_ADDQ return 1 if it managed to add the
item, 0 (because it was already in a list) otherwise.
Make it so MT_LIST_DEL returns 1 if it managed to remove the item from a
list, or 0 otherwise (because it was in no list).
diff --git a/include/common/mini-clist.h b/include/common/mini-clist.h
index 3d51919..9e1033e 100644
--- a/include/common/mini-clist.h
+++ b/include/common/mini-clist.h
@@ -204,10 +204,17 @@
/*
* Locked version of list manipulation macros.
* It is OK to use those concurrently from multiple threads, as long as the
- * list is only used with the locked variants. The only "unlocked" macro you
- * can use with a locked list is LIST_INIT.
+ * list is only used with the locked variants.
+ */
+
+/*
+ * Add an item at the beginning of a list.
+ * Returns 1 if we added the item, 0 otherwise (because it was already in a
+ * list).
*/
#define MT_LIST_ADD(lh, el) \
+ ({ \
+ int _ret = 0; \
do { \
while (1) { \
struct mt_list *n; \
@@ -233,11 +240,21 @@
__ha_barrier_store(); \
p->next = (el); \
__ha_barrier_store(); \
+ _ret = 1; \
break; \
} \
- } while (0)
+ } while (0); \
+ (_ret); \
+ })
+/*
+ * Add an item at the end of a list.
+ * Returns 1 if we added the item, 0 otherwise (because it was already in a
+ * list).
+ */
#define MT_LIST_ADDQ(lh, el) \
+ ({ \
+ int _ret = 0; \
do { \
while (1) { \
struct mt_list *n; \
@@ -263,11 +280,19 @@
__ha_barrier_store(); \
n->prev = (el); \
__ha_barrier_store(); \
+ _ret = 1; \
break; \
} \
- } while (0)
+ } while (0); \
+ (_ret); \
+ })
+/* Remove an item from a list.
+ * Returns 1 if we removed the item, 0 otherwise (because it was in no list).
+ */
#define MT_LIST_DEL(el) \
+ ({ \
+ int _ret = 0; \
do { \
while (1) { \
struct mt_list *n, *n2; \
@@ -303,13 +328,17 @@
} \
n->prev = p; \
p->next = n; \
+ if (p != (el) && n != (el)) \
+ _ret = 1; \
__ha_barrier_store(); \
(el)->prev = (el); \
(el)->next = (el); \
__ha_barrier_store(); \
break; \
} \
- } while (0)
+ } while (0); \
+ (_ret); \
+ })
/* Remove the first element from the list, and return it */