On Mon, May 22, 2023 at 7:21 PM T.J. Alumbaugh <talumbau@xxxxxxxxxx> wrote:
>
> 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
>
Reviewed-by: Yuanchu Xie <yuanchu@xxxxxxxxxx>
