[PATCH v4 22/48] mm: workingset: dynamically allocate the mm-shadow shrinker

[Qi Zheng via Linux-erofs]

Use new APIs to dynamically allocate the mm-shadow shrinker.

Signed-off-by: Qi Zheng <zhengqi.a...@bytedance.com>
---
 mm/workingset.c | 27 ++++++++++++++-------------
 1 file changed, 14 insertions(+), 13 deletions(-)

diff --git a/mm/workingset.c b/mm/workingset.c
index da58a26d0d4d..3c53138903a7 100644
--- a/mm/workingset.c
+++ b/mm/workingset.c
@@ -763,13 +763,6 @@ static unsigned long scan_shadow_nodes(struct shrinker 
*shrinker,
                                        NULL);
 }
 
-static struct shrinker workingset_shadow_shrinker = {
-       .count_objects = count_shadow_nodes,
-       .scan_objects = scan_shadow_nodes,
-       .seeks = 0, /* ->count reports only fully expendable nodes */
-       .flags = SHRINKER_NUMA_AWARE | SHRINKER_MEMCG_AWARE,
-};
-
 /*
  * Our list_lru->lock is IRQ-safe as it nests inside the IRQ-safe
  * i_pages lock.
@@ -778,9 +771,10 @@ static struct lock_class_key shadow_nodes_key;
 
 static int __init workingset_init(void)
 {
+       struct shrinker *workingset_shadow_shrinker;
        unsigned int timestamp_bits;
        unsigned int max_order;
-       int ret;
+       int ret = -ENOMEM;
 
        BUILD_BUG_ON(BITS_PER_LONG < EVICTION_SHIFT);
        /*
@@ -797,17 +791,24 @@ static int __init workingset_init(void)
        pr_info("workingset: timestamp_bits=%d max_order=%d bucket_order=%u\n",
               timestamp_bits, max_order, bucket_order);
 
-       ret = prealloc_shrinker(&workingset_shadow_shrinker, "mm-shadow");
-       if (ret)
+       workingset_shadow_shrinker = shrinker_alloc(SHRINKER_NUMA_AWARE |
+                                                   SHRINKER_MEMCG_AWARE,
+                                                   "mm-shadow");
+       if (!workingset_shadow_shrinker)
                goto err;
+
        ret = __list_lru_init(&shadow_nodes, true, &shadow_nodes_key,
-                             &workingset_shadow_shrinker);
+                             workingset_shadow_shrinker);
        if (ret)
                goto err_list_lru;
-       register_shrinker_prepared(&workingset_shadow_shrinker);
+
+       workingset_shadow_shrinker->count_objects = count_shadow_nodes;
+       workingset_shadow_shrinker->scan_objects = scan_shadow_nodes;
+
+       shrinker_register(workingset_shadow_shrinker);
        return 0;
 err_list_lru:
-       free_prealloced_shrinker(&workingset_shadow_shrinker);
+       shrinker_free(workingset_shadow_shrinker);
 err:
        return ret;
 }
-- 
2.30.2