@@ -1993,12 +1993,73 @@ static void xa_node_ctor(void *arg)
INIT_LIST_HEAD(&node->private_list);
}
+static void xa_object_migrate(struct xa_node *node, int numa_node)
+{
+ struct xarray *xa = READ_ONCE(node->array);
+ void __rcu **slot;
+ struct xa_node *new_node;
+ int i;
+
+ /* Freed or not yet in tree then skip */
+ if (!xa || xa == XA_RCU_FREE)
+ return;
+
+ new_node = kmem_cache_alloc_node(xa_node_cachep, GFP_KERNEL, numa_node);
+ if (!new_node) {
+ pr_err("%s: slab cache allocation failed\n", __func__);
+ return;
+ }
+
+ xa_lock_irq(xa);
+
+ /* Check again..... */
+ if (xa != node->array) {
+ node = new_node;
+ goto unlock;
+ }
+
+ memcpy(new_node, node, sizeof(struct xa_node));
+
+ if (list_empty(&node->private_list))
+ INIT_LIST_HEAD(&new_node->private_list);
+ else
+ list_replace(&node->private_list, &new_node->private_list);
+
+ for (i = 0; i < XA_CHUNK_SIZE; i++) {
+ void *x = xa_entry_locked(xa, new_node, i);
+
+ if (xa_is_node(x))
+ rcu_assign_pointer(xa_to_node(x)->parent, new_node);
+ }
+ if (!new_node->parent)
+ slot = &xa->xa_head;
+ else
+ slot = &xa_parent_locked(xa, new_node)->slots[new_node->offset];
+ rcu_assign_pointer(*slot, xa_mk_node(new_node));
+
+unlock:
+ xa_unlock_irq(xa);
+ xa_node_free(node);
+ rcu_barrier();
+}
+
+static void xa_migrate(struct kmem_cache *s, void **objects, int nr,
+ int node, void *_unused)
+{
+ int i;
+
+ for (i = 0; i < nr; i++)
+ xa_object_migrate(objects[i], node);
+}
+
+
void __init xarray_slabcache_init(void)
{
xa_node_cachep = kmem_cache_create("xarray_node",
sizeof(struct xa_node), 0,
SLAB_PANIC | SLAB_RECLAIM_ACCOUNT,
xa_node_ctor);
+ kmem_cache_setup_mobility(xa_node_cachep, NULL, xa_migrate);
}
#ifdef XA_DEBUG
Recently Slab Movable Objects (SMO) was implemented for the SLUB allocator. The XArray can take advantage of this and make the xa_node slab cache objects movable. Implement functions to migrate objects and activate SMO when we initialise the XArray slab cache. This is based on initial code by Matthew Wilcox and was modified to work with slab object migration. Cc: Matthew Wilcox <willy@infradead.org> Co-developed-by: Christoph Lameter <cl@linux.com> Signed-off-by: Tobin C. Harding <tobin@kernel.org> --- lib/xarray.c | 61 ++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 61 insertions(+)