-/**
- * Callback function for shrink policy. Makes decision whether to keep
- * \a lock in LRU for current \a LRU size \a unused, added in current scan
- * \a added and number of locks to be preferably canceled \a count.
- *
- * \retval LDLM_POLICY_KEEP_LOCK keep lock in LRU in stop scanning
- *
- * \retval LDLM_POLICY_CANCEL_LOCK cancel lock from LRU
- */
-static ldlm_policy_res_t ldlm_cancel_shrink_policy(struct ldlm_namespace *ns,
- struct ldlm_lock *lock,
- int unused, int added,
- int count)
-{
- int lock_cost;
- __u64 page_nr;
-
- /*
- * Stop lru processing when we reached passed @count or checked all
- * locks in lru.
- */
- if (count && added >= count)
- return LDLM_POLICY_KEEP_LOCK;
-
- if (lock->l_resource->lr_type == LDLM_EXTENT) {
- struct ldlm_extent *l_extent;
-
- /*
- * For all extent locks cost is 1 + number of pages in
- * their extent.
- */
- l_extent = &lock->l_policy_data.l_extent;
- page_nr = (l_extent->end - l_extent->start);
- do_div(page_nr, CFS_PAGE_SIZE);
-
-#ifdef __KERNEL__
- /*
- * XXX: In fact this is evil hack, we can't access inode
- * here. For doing it right we need somehow to have number
- * of covered by lock. This should be fixed later when 10718
- * is landed.
- */
- if (lock->l_ast_data != NULL) {
- struct inode *inode = lock->l_ast_data;
- if (page_nr > inode->i_mapping->nrpages)
- page_nr = inode->i_mapping->nrpages;
- }
-#endif
- lock_cost = 1 + page_nr;
- } else {
- /*
- * For all locks which are not extent ones cost is 1
- */
- lock_cost = 1;
- }
-
- /*
- * Keep all expensive locks in lru for the memory pressure time
- * cancel policy. They anyways may be canceled by lru resize
- * pplicy if they have not small enough CLV.
- */
- return lock_cost > ns->ns_shrink_thumb ?
- LDLM_POLICY_KEEP_LOCK : LDLM_POLICY_CANCEL_LOCK;
-}
-