diff options
Diffstat (limited to 'mm/vmscan.c')
| -rw-r--r-- | mm/vmscan.c | 23 |
1 files changed, 21 insertions, 2 deletions
diff --git a/mm/vmscan.c b/mm/vmscan.c index 8b920ce3ae02..9270a4370d54 100644 --- a/mm/vmscan.c +++ b/mm/vmscan.c @@ -303,7 +303,7 @@ unsigned long lruvec_lru_size(struct lruvec *lruvec, enum lru_list lru, int zone /* * Add a shrinker callback to be called from the vm. */ -int register_shrinker(struct shrinker *shrinker) +int prealloc_shrinker(struct shrinker *shrinker) { size_t size = sizeof(*shrinker->nr_deferred); @@ -313,10 +313,29 @@ int register_shrinker(struct shrinker *shrinker) shrinker->nr_deferred = kzalloc(size, GFP_KERNEL); if (!shrinker->nr_deferred) return -ENOMEM; + return 0; +} + +void free_prealloced_shrinker(struct shrinker *shrinker) +{ + kfree(shrinker->nr_deferred); + shrinker->nr_deferred = NULL; +} +void register_shrinker_prepared(struct shrinker *shrinker) +{ down_write(&shrinker_rwsem); list_add_tail(&shrinker->list, &shrinker_list); up_write(&shrinker_rwsem); +} + +int register_shrinker(struct shrinker *shrinker) +{ + int err = prealloc_shrinker(shrinker); + + if (err) + return err; + register_shrinker_prepared(shrinker); return 0; } EXPORT_SYMBOL(register_shrinker); @@ -1399,7 +1418,7 @@ int __isolate_lru_page(struct page *page, isolate_mode_t mode) return ret; mapping = page_mapping(page); - migrate_dirty = mapping && mapping->a_ops->migratepage; + migrate_dirty = !mapping || mapping->a_ops->migratepage; unlock_page(page); if (!migrate_dirty) return ret; |