mm: Convert workingset to XArray
We construct an XA_STATE and use it to delete the node with
xas_store() rather than adding a special function for this unique
use case. Includes a test that simulates this usage for the
test suite.
Signed-off-by: Matthew Wilcox <[email protected]>
diff --git a/lib/test_xarray.c b/lib/test_xarray.c
index a752e6a..128c648 100644
--- a/lib/test_xarray.c
+++ b/lib/test_xarray.c
@@ -863,6 +863,67 @@ static noinline void check_create_range(struct xarray *xa)
check_create_range_3();
}
+static LIST_HEAD(shadow_nodes);
+
+static void test_update_node(struct xa_node *node)
+{
+ if (node->count && node->count == node->nr_values) {
+ if (list_empty(&node->private_list))
+ list_add(&shadow_nodes, &node->private_list);
+ } else {
+ if (!list_empty(&node->private_list))
+ list_del_init(&node->private_list);
+ }
+}
+
+static noinline void shadow_remove(struct xarray *xa)
+{
+ struct xa_node *node;
+
+ xa_lock(xa);
+ while ((node = list_first_entry_or_null(&shadow_nodes,
+ struct xa_node, private_list))) {
+ XA_STATE(xas, node->array, 0);
+ XA_BUG_ON(xa, node->array != xa);
+ list_del_init(&node->private_list);
+ xas.xa_node = xa_parent_locked(node->array, node);
+ xas.xa_offset = node->offset;
+ xas.xa_shift = node->shift + XA_CHUNK_SHIFT;
+ xas_set_update(&xas, test_update_node);
+ xas_store(&xas, NULL);
+ }
+ xa_unlock(xa);
+}
+
+static noinline void check_workingset(struct xarray *xa, unsigned long index)
+{
+ XA_STATE(xas, xa, index);
+ xas_set_update(&xas, test_update_node);
+
+ do {
+ xas_lock(&xas);
+ xas_store(&xas, xa_mk_value(0));
+ xas_next(&xas);
+ xas_store(&xas, xa_mk_value(1));
+ xas_unlock(&xas);
+ } while (xas_nomem(&xas, GFP_KERNEL));
+
+ XA_BUG_ON(xa, list_empty(&shadow_nodes));
+
+ xas_lock(&xas);
+ xas_next(&xas);
+ xas_store(&xas, &xas);
+ XA_BUG_ON(xa, !list_empty(&shadow_nodes));
+
+ xas_store(&xas, xa_mk_value(2));
+ xas_unlock(&xas);
+ XA_BUG_ON(xa, list_empty(&shadow_nodes));
+
+ shadow_remove(xa);
+ XA_BUG_ON(xa, !list_empty(&shadow_nodes));
+ XA_BUG_ON(xa, !xa_empty(xa));
+}
+
static noinline void check_destroy(struct xarray *xa)
{
unsigned long index;
@@ -916,6 +977,10 @@ static int xarray_checks(void)
check_create_range(&array);
check_store_iter(&array);
+ check_workingset(&array, 0);
+ check_workingset(&array, 64);
+ check_workingset(&array, 4096);
+
printk("XArray: %u of %u tests passed\n", tests_passed, tests_run);
return (tests_run == tests_passed) ? 0 : -EINVAL;
}
