BACKPORT: mm: multi-gen LRU: groundwork

[platform/kernel/linux-rpi.git] / mm / vmscan.c

diff --git a/mm/vmscan.c b/mm/vmscan.c
index 247d5c5..12759c4 100644 (file)
--- a/mm/vmscan.c
+++ b/mm/vmscan.c
@@ -2531,6 +2531,81 @@ out:
        }
 }
 
+#ifdef CONFIG_LRU_GEN
+
+/******************************************************************************
+ *                          shorthand helpers
+ ******************************************************************************/
+
+#define for_each_gen_type_zone(gen, type, zone)                                \
+       for ((gen) = 0; (gen) < MAX_NR_GENS; (gen)++)                   \
+               for ((type) = 0; (type) < ANON_AND_FILE; (type)++)      \
+                       for ((zone) = 0; (zone) < MAX_NR_ZONES; (zone)++)
+
+static struct lruvec __maybe_unused *get_lruvec(struct mem_cgroup *memcg, int nid)
+{
+       struct pglist_data *pgdat = NODE_DATA(nid);
+
+#ifdef CONFIG_MEMCG
+       if (memcg) {
+               struct lruvec *lruvec = &memcg->nodeinfo[nid]->lruvec;
+
+               /* for hotadd_new_pgdat() */
+               if (!lruvec->pgdat)
+                       lruvec->pgdat = pgdat;
+
+               return lruvec;
+       }
+#endif
+       VM_WARN_ON_ONCE(!mem_cgroup_disabled());
+
+       return pgdat ? &pgdat->__lruvec : NULL;
+}
+
+/******************************************************************************
+ *                          initialization
+ ******************************************************************************/
+
+void lru_gen_init_lruvec(struct lruvec *lruvec)
+{
+       int gen, type, zone;
+       struct lru_gen_struct *lrugen = &lruvec->lrugen;
+
+       lrugen->max_seq = MIN_NR_GENS + 1;
+
+       for_each_gen_type_zone(gen, type, zone)
+               INIT_LIST_HEAD(&lrugen->lists[gen][type][zone]);
+}
+
+#ifdef CONFIG_MEMCG
+void lru_gen_init_memcg(struct mem_cgroup *memcg)
+{
+}
+
+void lru_gen_exit_memcg(struct mem_cgroup *memcg)
+{
+       int nid;
+
+       for_each_node(nid) {
+               struct lruvec *lruvec = get_lruvec(memcg, nid);
+
+               VM_WARN_ON_ONCE(memchr_inv(lruvec->lrugen.nr_pages, 0,
+                                          sizeof(lruvec->lrugen.nr_pages)));
+       }
+}
+#endif
+
+static int __init init_lru_gen(void)
+{
+       BUILD_BUG_ON(MIN_NR_GENS + 1 >= MAX_NR_GENS);
+       BUILD_BUG_ON(BIT(LRU_GEN_WIDTH) <= MAX_NR_GENS);
+
+       return 0;
+};
+late_initcall(init_lru_gen);
+
+#endif /* CONFIG_LRU_GEN */
+
 static void shrink_lruvec(struct lruvec *lruvec, struct scan_control *sc)
 {
        unsigned long nr[NR_LRU_LISTS];