[PATCH mm-unstable v4 3/5] mm/mglru: remove CONFIG_MEMCG
From: Kinsey Ho
Date: Wed Dec 27 2023 - 09:13:19 EST
Remove CONFIG_MEMCG in a refactoring to improve code readability at
the cost of a few bytes in struct lru_gen_folio per node when
CONFIG_MEMCG=n.
Signed-off-by: Kinsey Ho <kinseyho@xxxxxxxxxx>
Co-developed-by: Aneesh Kumar K.V <aneesh.kumar@xxxxxxxxxxxxx>
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@xxxxxxxxxxxxx>
Tested-by: Donet Tom <donettom@xxxxxxxxxxxxxxxxxx>
Acked-by: Yu Zhao <yuzhao@xxxxxxxxxx>
---
include/linux/mm_types.h | 4 ---
include/linux/mmzone.h | 26 ++--------------
mm/vmscan.c | 67 +++++++++++++---------------------------
3 files changed, 23 insertions(+), 74 deletions(-)
diff --git a/include/linux/mm_types.h b/include/linux/mm_types.h
index 552fa2d11c57..55b7121809ff 100644
--- a/include/linux/mm_types.h
+++ b/include/linux/mm_types.h
@@ -1017,9 +1017,7 @@ struct lru_gen_mm_list {
void lru_gen_add_mm(struct mm_struct *mm);
void lru_gen_del_mm(struct mm_struct *mm);
-#ifdef CONFIG_MEMCG
void lru_gen_migrate_mm(struct mm_struct *mm);
-#endif
static inline void lru_gen_init_mm(struct mm_struct *mm)
{
@@ -1050,11 +1048,9 @@ static inline void lru_gen_del_mm(struct mm_struct *mm)
{
}
-#ifdef CONFIG_MEMCG
static inline void lru_gen_migrate_mm(struct mm_struct *mm)
{
}
-#endif
static inline void lru_gen_init_mm(struct mm_struct *mm)
{
diff --git a/include/linux/mmzone.h b/include/linux/mmzone.h
index bc3f63ec4291..28665e1b8475 100644
--- a/include/linux/mmzone.h
+++ b/include/linux/mmzone.h
@@ -440,14 +440,12 @@ struct lru_gen_folio {
atomic_long_t refaulted[NR_HIST_GENS][ANON_AND_FILE][MAX_NR_TIERS];
/* whether the multi-gen LRU is enabled */
bool enabled;
-#ifdef CONFIG_MEMCG
/* the memcg generation this lru_gen_folio belongs to */
u8 gen;
/* the list segment this lru_gen_folio belongs to */
u8 seg;
/* per-node lru_gen_folio list for global reclaim */
struct hlist_nulls_node list;
-#endif
};
enum {
@@ -493,11 +491,6 @@ struct lru_gen_mm_walk {
bool force_scan;
};
-void lru_gen_init_lruvec(struct lruvec *lruvec);
-void lru_gen_look_around(struct page_vma_mapped_walk *pvmw);
-
-#ifdef CONFIG_MEMCG
-
/*
* For each node, memcgs are divided into two generations: the old and the
* young. For each generation, memcgs are randomly sharded into multiple bins
@@ -555,6 +548,8 @@ struct lru_gen_memcg {
};
void lru_gen_init_pgdat(struct pglist_data *pgdat);
+void lru_gen_init_lruvec(struct lruvec *lruvec);
+void lru_gen_look_around(struct page_vma_mapped_walk *pvmw);
void lru_gen_init_memcg(struct mem_cgroup *memcg);
void lru_gen_exit_memcg(struct mem_cgroup *memcg);
@@ -563,19 +558,6 @@ void lru_gen_offline_memcg(struct mem_cgroup *memcg);
void lru_gen_release_memcg(struct mem_cgroup *memcg);
void lru_gen_soft_reclaim(struct mem_cgroup *memcg, int nid);
-#else /* !CONFIG_MEMCG */
-
-#define MEMCG_NR_GENS 1
-
-struct lru_gen_memcg {
-};
-
-static inline void lru_gen_init_pgdat(struct pglist_data *pgdat)
-{
-}
-
-#endif /* CONFIG_MEMCG */
-
#else /* !CONFIG_LRU_GEN */
static inline void lru_gen_init_pgdat(struct pglist_data *pgdat)
@@ -590,8 +572,6 @@ static inline void lru_gen_look_around(struct page_vma_mapped_walk *pvmw)
{
}
-#ifdef CONFIG_MEMCG
-
static inline void lru_gen_init_memcg(struct mem_cgroup *memcg)
{
}
@@ -616,8 +596,6 @@ static inline void lru_gen_soft_reclaim(struct mem_cgroup *memcg, int nid)
{
}
-#endif /* CONFIG_MEMCG */
-
#endif /* CONFIG_LRU_GEN */
struct lruvec {
diff --git a/mm/vmscan.c b/mm/vmscan.c
index aa7ea09ffb4c..351a0b5043c0 100644
--- a/mm/vmscan.c
+++ b/mm/vmscan.c
@@ -4097,13 +4097,6 @@ enum {
MEMCG_LRU_YOUNG,
};
-#ifdef CONFIG_MEMCG
-
-static int lru_gen_memcg_seg(struct lruvec *lruvec)
-{
- return READ_ONCE(lruvec->lrugen.seg);
-}
-
static void lru_gen_rotate_memcg(struct lruvec *lruvec, int op)
{
int seg;
@@ -4150,6 +4143,8 @@ static void lru_gen_rotate_memcg(struct lruvec *lruvec, int op)
spin_unlock_irqrestore(&pgdat->memcg_lru.lock, flags);
}
+#ifdef CONFIG_MEMCG
+
void lru_gen_online_memcg(struct mem_cgroup *memcg)
{
int gen;
@@ -4217,18 +4212,11 @@ void lru_gen_soft_reclaim(struct mem_cgroup *memcg, int nid)
struct lruvec *lruvec = get_lruvec(memcg, nid);
/* see the comment on MEMCG_NR_GENS */
- if (lru_gen_memcg_seg(lruvec) != MEMCG_LRU_HEAD)
+ if (READ_ONCE(lruvec->lrugen.seg) != MEMCG_LRU_HEAD)
lru_gen_rotate_memcg(lruvec, MEMCG_LRU_HEAD);
}
-#else /* !CONFIG_MEMCG */
-
-static int lru_gen_memcg_seg(struct lruvec *lruvec)
-{
- return 0;
-}
-
-#endif
+#endif /* CONFIG_MEMCG */
/******************************************************************************
* the eviction
@@ -4776,7 +4764,7 @@ static int shrink_one(struct lruvec *lruvec, struct scan_control *sc)
if (mem_cgroup_below_low(NULL, memcg)) {
/* see the comment on MEMCG_NR_GENS */
- if (lru_gen_memcg_seg(lruvec) != MEMCG_LRU_TAIL)
+ if (READ_ONCE(lruvec->lrugen.seg) != MEMCG_LRU_TAIL)
return MEMCG_LRU_TAIL;
memcg_memory_event(memcg, MEMCG_LOW);
@@ -4799,12 +4787,10 @@ static int shrink_one(struct lruvec *lruvec, struct scan_control *sc)
return 0;
/* one retry if offlined or too small */
- return lru_gen_memcg_seg(lruvec) != MEMCG_LRU_TAIL ?
+ return READ_ONCE(lruvec->lrugen.seg) != MEMCG_LRU_TAIL ?
MEMCG_LRU_TAIL : MEMCG_LRU_YOUNG;
}
-#ifdef CONFIG_MEMCG
-
static void shrink_many(struct pglist_data *pgdat, struct scan_control *sc)
{
int op;
@@ -4896,20 +4882,6 @@ static void lru_gen_shrink_lruvec(struct lruvec *lruvec, struct scan_control *sc
blk_finish_plug(&plug);
}
-#else /* !CONFIG_MEMCG */
-
-static void shrink_many(struct pglist_data *pgdat, struct scan_control *sc)
-{
- BUILD_BUG();
-}
-
-static void lru_gen_shrink_lruvec(struct lruvec *lruvec, struct scan_control *sc)
-{
- BUILD_BUG();
-}
-
-#endif
-
static void set_initial_priority(struct pglist_data *pgdat, struct scan_control *sc)
{
int priority;
@@ -5560,6 +5532,18 @@ static const struct file_operations lru_gen_ro_fops = {
* initialization
******************************************************************************/
+void lru_gen_init_pgdat(struct pglist_data *pgdat)
+{
+ int i, j;
+
+ spin_lock_init(&pgdat->memcg_lru.lock);
+
+ for (i = 0; i < MEMCG_NR_GENS; i++) {
+ for (j = 0; j < MEMCG_NR_BINS; j++)
+ INIT_HLIST_NULLS_HEAD(&pgdat->memcg_lru.fifo[i][j], i);
+ }
+}
+
void lru_gen_init_lruvec(struct lruvec *lruvec)
{
int i;
@@ -5582,18 +5566,6 @@ void lru_gen_init_lruvec(struct lruvec *lruvec)
#ifdef CONFIG_MEMCG
-void lru_gen_init_pgdat(struct pglist_data *pgdat)
-{
- int i, j;
-
- spin_lock_init(&pgdat->memcg_lru.lock);
-
- for (i = 0; i < MEMCG_NR_GENS; i++) {
- for (j = 0; j < MEMCG_NR_BINS; j++)
- INIT_HLIST_NULLS_HEAD(&pgdat->memcg_lru.fifo[i][j], i);
- }
-}
-
void lru_gen_init_memcg(struct mem_cgroup *memcg)
{
struct lru_gen_mm_list *mm_list = get_mm_list(memcg);
@@ -5653,14 +5625,17 @@ late_initcall(init_lru_gen);
static void lru_gen_age_node(struct pglist_data *pgdat, struct scan_control *sc)
{
+ BUILD_BUG();
}
static void lru_gen_shrink_lruvec(struct lruvec *lruvec, struct scan_control *sc)
{
+ BUILD_BUG();
}
static void lru_gen_shrink_node(struct pglist_data *pgdat, struct scan_control *sc)
{
+ BUILD_BUG();
}
#endif /* CONFIG_LRU_GEN */
--
2.43.0.472.g3155946c3a-goog