Function bt_freetrim

freebsd/kern/subr_vmem.c:339–358

* Trim the per-vmem free list. Returns with the lock released to * avoid allocator recursions. */

 * avoid allocator recursions.
 */
static void
bt_freetrim(vmem_t *vm, int freelimit)
{
	LIST_HEAD(, vmem_btag) freetags;
	bt_t *bt;

	LIST_INIT(&freetags);
	VMEM_ASSERT_LOCKED(vm);
	while (vm->vm_nfreetags > freelimit) {
		bt = LIST_FIRST(&vm->vm_freetags);
		LIST_REMOVE(bt, bt_freelist);
		vm->vm_nfreetags--;
		LIST_INSERT_HEAD(&freetags, bt, bt_freelist);
	}
	VMEM_UNLOCK(vm);
	while ((bt = LIST_FIRST(&freetags)) != NULL) {
		LIST_REMOVE(bt, bt_freelist);
		uma_zfree(vmem_bt_zone, bt);
	}
}

static inline void
bt_free(vmem_t *vm, bt_t *bt)