[PATCH mm-unstable 4/4] mm: multi-gen LRU: cleanup lru_gen_test_recent()

From: T.J. Alumbaugh
Date: Mon May 22 2023 - 07:25:33 EST


Avoid passing memcg* and pglist_data* to lru_gen_test_recent()
since we only use the lruvec anyway.

Signed-off-by: T.J. Alumbaugh <talumbau@xxxxxxxxxx>
---
mm/workingset.c | 46 ++++++++++++++++------------------------------
1 file changed, 16 insertions(+), 30 deletions(-)

diff --git a/mm/workingset.c b/mm/workingset.c
index 90ae785d4c9c..5796e927e6d7 100644
--- a/mm/workingset.c
+++ b/mm/workingset.c
@@ -257,59 +257,46 @@ static void *lru_gen_eviction(struct folio *folio)

/*
* Tests if the shadow entry is for a folio that was recently evicted.
- * Fills in @memcgid, @pglist_data, @token, @workingset with the values
- * unpacked from shadow.
+ * Fills in @lruvec, @token, @workingset with the values unpacked from shadow.
*/
-static bool lru_gen_test_recent(void *shadow, bool file, int *memcgid,
- struct pglist_data **pgdat, unsigned long *token, bool *workingset)
+static bool lru_gen_test_recent(void *shadow, bool file, struct lruvec **lruvec,
+ unsigned long *token, bool *workingset)
{
- struct mem_cgroup *eviction_memcg;
- struct lruvec *lruvec;
- struct lru_gen_folio *lrugen;
+ int memcg_id;
unsigned long min_seq;
+ struct mem_cgroup *memcg;
+ struct pglist_data *pgdat;

- unpack_shadow(shadow, memcgid, pgdat, token, workingset);
- eviction_memcg = mem_cgroup_from_id(*memcgid);
+ unpack_shadow(shadow, &memcg_id, &pgdat, token, workingset);

- lruvec = mem_cgroup_lruvec(eviction_memcg, *pgdat);
- lrugen = &lruvec->lrugen;
+ memcg = mem_cgroup_from_id(memcg_id);
+ *lruvec = mem_cgroup_lruvec(memcg, pgdat);

- min_seq = READ_ONCE(lrugen->min_seq[file]);
+ min_seq = READ_ONCE((*lruvec)->lrugen.min_seq[file]);
return (*token >> LRU_REFS_WIDTH) == (min_seq & (EVICTION_MASK >> LRU_REFS_WIDTH));
}

static void lru_gen_refault(struct folio *folio, void *shadow)
{
int hist, tier, refs;
- int memcg_id;
bool workingset;
unsigned long token;
- unsigned long min_seq;
struct lruvec *lruvec;
struct lru_gen_folio *lrugen;
- struct mem_cgroup *memcg;
- struct pglist_data *pgdat;
int type = folio_is_file_lru(folio);
int delta = folio_nr_pages(folio);

rcu_read_lock();

- if (!lru_gen_test_recent(shadow, type, &memcg_id, &pgdat, &token,
- &workingset))
+ if (!lru_gen_test_recent(shadow, type, &lruvec, &token, &workingset))
goto unlock;

- memcg = folio_memcg_rcu(folio);
- if (memcg_id != mem_cgroup_id(memcg))
+ if (lruvec != folio_lruvec(folio))
goto unlock;

- if (pgdat != folio_pgdat(folio))
- goto unlock;
-
- lruvec = mem_cgroup_lruvec(memcg, pgdat);
lrugen = &lruvec->lrugen;
- min_seq = READ_ONCE(lrugen->min_seq[type]);

- hist = lru_hist_from_seq(min_seq);
+ hist = lru_hist_from_seq(READ_ONCE(lrugen->min_seq[type]));
/* see the comment in folio_lru_refs() */
refs = (token & (BIT(LRU_REFS_WIDTH) - 1)) + workingset;
tier = lru_tier_from_refs(refs);
@@ -339,8 +326,8 @@ static void *lru_gen_eviction(struct folio *folio)
return NULL;
}

-static bool lru_gen_test_recent(void *shadow, bool file, int *memcgid,
- struct pglist_data **pgdat, unsigned long *token, bool *workingset)
+static bool lru_gen_test_recent(void *shadow, bool file, struct lruvec **lruvec,
+ unsigned long *token, bool *workingset)
{
return false;
}
@@ -435,8 +422,7 @@ bool workingset_test_recent(void *shadow, bool file, bool *workingset)
unsigned long eviction;

if (lru_gen_enabled())
- return lru_gen_test_recent(shadow, file, &memcgid, &pgdat, &eviction,
- workingset);
+ return lru_gen_test_recent(shadow, file, &eviction_lruvec, &eviction, workingset);

unpack_shadow(shadow, &memcgid, &pgdat, &eviction, workingset);
eviction <<= bucket_order;
--
2.40.1.698.g37aff9b760-goog