[PATCH V3 1/4] mm: shrinker: add one more parameter in shrinker_id()

[Haifeng Xu]

Add a parameter points to target memory cgroup in shrinker_id().
The following patch will use it to decide the id of shrinker.
No functional change here.

Signed-off-by: Haifeng Xu <haifeng.xu@xxxxxxxxxx>
---
 include/linux/memcontrol.h |  4 ++--
 mm/huge_memory.c           |  4 ++--
 mm/shrinker.c              | 12 ++++++++----
 3 files changed, 12 insertions(+), 8 deletions(-)

diff --git a/include/linux/memcontrol.h b/include/linux/memcontrol.h
index 70b685a85bf4..a583dbc0adcc 100644
--- a/include/linux/memcontrol.h
+++ b/include/linux/memcontrol.h
@@ -1634,7 +1634,7 @@ void free_shrinker_info(struct mem_cgroup *memcg);
 void set_shrinker_bit(struct mem_cgroup *memcg, int nid, int shrinker_id);
 void reparent_shrinker_deferred(struct mem_cgroup *memcg);
 
-static inline int shrinker_id(struct shrinker *shrinker)
+static inline int shrinker_id(struct mem_cgroup *memcg, struct shrinker *shrinker)
 {
 	return shrinker->id;
 }
@@ -1670,7 +1670,7 @@ static inline void set_shrinker_bit(struct mem_cgroup *memcg,
 {
 }
 
-static inline int shrinker_id(struct shrinker *shrinker)
+static inline int shrinker_id(struct mem_cgroup *memcg, struct shrinker *shrinker)
 {
 	return -1;
 }
diff --git a/mm/huge_memory.c b/mm/huge_memory.c
index 8e2746ea74ad..6050f8d71587 100644
--- a/mm/huge_memory.c
+++ b/mm/huge_memory.c
@@ -4353,7 +4353,7 @@ void deferred_split_folio(struct folio *folio, bool partially_mapped)
 		ds_queue->split_queue_len++;
 		if (memcg)
 			set_shrinker_bit(memcg, folio_nid(folio),
-					 shrinker_id(deferred_split_shrinker));
+					 shrinker_id(memcg, deferred_split_shrinker));
 	}
 	split_queue_unlock_irqrestore(ds_queue, flags);
 }
@@ -4509,7 +4509,7 @@ void reparent_deferred_split_queue(struct mem_cgroup *memcg)
 	ds_queue->split_queue_len = 0;
 
 	for_each_node(nid)
-		set_shrinker_bit(parent, nid, shrinker_id(deferred_split_shrinker));
+		set_shrinker_bit(parent, nid, shrinker_id(parent, deferred_split_shrinker));
 
 unlock:
 	spin_unlock(&parent_ds_queue->split_queue_lock);
diff --git a/mm/shrinker.c b/mm/shrinker.c
index 7b61fc0ee78f..61dbb6afae52 100644
--- a/mm/shrinker.c
+++ b/mm/shrinker.c
@@ -255,11 +255,13 @@ static long xchg_nr_deferred_memcg(int nid, struct shrinker *shrinker,
 	struct shrinker_info *info;
 	struct shrinker_info_unit *unit;
 	long nr_deferred;
+	int id;
 
 	rcu_read_lock();
+	id = shrinker_id(memcg, shrinker);
 	info = rcu_dereference(memcg->nodeinfo[nid]->shrinker_info);
-	unit = info->unit[shrinker_id_to_index(shrinker->id)];
-	nr_deferred = atomic_long_xchg(&unit->nr_deferred[shrinker_id_to_offset(shrinker->id)], 0);
+	unit = info->unit[shrinker_id_to_index(id)];
+	nr_deferred = atomic_long_xchg(&unit->nr_deferred[shrinker_id_to_offset(id)], 0);
 	rcu_read_unlock();
 
 	return nr_deferred;
@@ -271,12 +273,14 @@ static long add_nr_deferred_memcg(long nr, int nid, struct shrinker *shrinker,
 	struct shrinker_info *info;
 	struct shrinker_info_unit *unit;
 	long nr_deferred;
+	int id;
 
 	rcu_read_lock();
+	id = shrinker_id(memcg, shrinker);
 	info = rcu_dereference(memcg->nodeinfo[nid]->shrinker_info);
-	unit = info->unit[shrinker_id_to_index(shrinker->id)];
+	unit = info->unit[shrinker_id_to_index(id)];
 	nr_deferred =
-		atomic_long_add_return(nr, &unit->nr_deferred[shrinker_id_to_offset(shrinker->id)]);
+		atomic_long_add_return(nr, &unit->nr_deferred[shrinker_id_to_offset(id)]);
 	rcu_read_unlock();
 
 	return nr_deferred;
-- 
2.43.0