This helper is used to provide a callback to be called for each lruvec
list. This abstracts different lruvec implementations (MGLRU vs. classic
LRUs). The helper is used by a following commit to iterate all folios in
all LRUs lists for memcg recharging.
Signed-off-by: Yosry Ahmed <yosryahmed@xxxxxxxxxx>
---
include/linux/swap.h | 8 ++++++++
mm/vmscan.c | 28 ++++++++++++++++++++++++++++
2 files changed, 36 insertions(+)
diff --git a/include/linux/swap.h b/include/linux/swap.h
index 456546443f1f..c0621deceb03 100644
--- a/include/linux/swap.h
+++ b/include/linux/swap.h
@@ -406,6 +406,14 @@ extern void lru_cache_add_inactive_or_unevictable(struct page *page,
struct vm_area_struct *vma);
/* linux/mm/vmscan.c */
+typedef bool (*lruvec_list_fn_t)(struct lruvec *lruvec,
+ struct list_head *list,
+ enum lru_list lru,
+ void *arg);
+extern void lruvec_for_each_list(struct lruvec *lruvec,
+ lruvec_list_fn_t fn,
+ void *arg);
+
extern unsigned long zone_reclaimable_pages(struct zone *zone);
extern unsigned long try_to_free_pages(struct zonelist *zonelist, int order,
gfp_t gfp_mask, nodemask_t *mask);
diff --git a/mm/vmscan.c b/mm/vmscan.c
index 1080209a568b..e7956000a3b6 100644
--- a/mm/vmscan.c
+++ b/mm/vmscan.c
@@ -6254,6 +6254,34 @@ static void lru_gen_shrink_node(struct pglist_data *pgdat, struct scan_control *
#endif /* CONFIG_LRU_GEN */
+/*
+ * lruvec_for_each_list - make a callback for every folio list in the lruvec
+ * @lruvec: the lruvec to iterate lists in
+ * @fn: the callback to make for each list, iteration stops if it returns true
+ * @arg: argument to pass to @fn
+ */
+void lruvec_for_each_list(struct lruvec *lruvec, lruvec_list_fn_t fn, void *arg)
+{
+ enum lru_list lru;
+
+#ifdef CONFIG_LRU_GEN
+ if (lru_gen_enabled()) {
+ int gen, type, zone;
+
+ for_each_gen_type_zone(gen, type, zone) {
+ lru = type * LRU_INACTIVE_FILE;
+ if (fn(lruvec, &lruvec->lrugen.folios[gen][type][zone],
+ lru, arg))
+ break;
+ }
+ } else
+#endif
+ for_each_evictable_lru(lru) {
+ if (fn(lruvec, &lruvec->lists[lru], lru, arg))
+ break;
+ }
+}
+
static void shrink_lruvec(struct lruvec *lruvec, struct scan_control *sc)
{
unsigned long nr[NR_LRU_LISTS];
--
2.41.0.255.g8b1d071c50-goog
