return pack_shadow(mem_cgroup_id(memcg), pgdat, token, refs);
}
+/*
+ * Tests if the shadow entry is for a folio that was recently evicted.
+ * Fills in @lruvec, @token, @workingset with the values unpacked from shadow.
+ */
+static bool lru_gen_test_recent(void *shadow, bool file, struct lruvec **lruvec,
+ unsigned long *token, bool *workingset)
+{
+ int memcg_id;
+ unsigned long min_seq;
+ struct mem_cgroup *memcg;
+ struct pglist_data *pgdat;
+
+ unpack_shadow(shadow, &memcg_id, &pgdat, token, workingset);
+
+ memcg = mem_cgroup_from_id(memcg_id);
+ *lruvec = mem_cgroup_lruvec(memcg, pgdat);
+
+ 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)
{
+ bool recent;
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);
- unpack_shadow(shadow, &memcg_id, &pgdat, &token, &workingset);
-
- if (pgdat != folio_pgdat(folio))
- return;
-
rcu_read_lock();
- memcg = folio_memcg_rcu(folio);
- if (memcg_id != mem_cgroup_id(memcg))
+ recent = lru_gen_test_recent(shadow, type, &lruvec, &token, &workingset);
+ if (lruvec != folio_lruvec(folio))
goto unlock;
- lruvec = mem_cgroup_lruvec(memcg, pgdat);
- lrugen = &lruvec->lrugen;
+ mod_lruvec_state(lruvec, WORKINGSET_REFAULT_BASE + type, delta);
- min_seq = READ_ONCE(lrugen->min_seq[type]);
- if ((token >> LRU_REFS_WIDTH) != (min_seq & (EVICTION_MASK >> LRU_REFS_WIDTH)))
+ if (!recent)
goto unlock;
- hist = lru_hist_from_seq(min_seq);
+ lrugen = &lruvec->lrugen;
+
+ 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);
atomic_long_add(delta, &lrugen->refaulted[hist][type][tier]);
- mod_lruvec_state(lruvec, WORKINGSET_REFAULT_BASE + type, delta);
+ mod_lruvec_state(lruvec, WORKINGSET_ACTIVATE_BASE + type, delta);
/*
* Count the following two cases as stalls:
return NULL;
}
+static bool lru_gen_test_recent(void *shadow, bool file, struct lruvec **lruvec,
+ unsigned long *token, bool *workingset)
+{
+ return false;
+}
+
static void lru_gen_refault(struct folio *folio, void *shadow)
{
}
}
/**
- * workingset_refault - Evaluate the refault of a previously evicted folio.
- * @folio: The freshly allocated replacement folio.
- * @shadow: Shadow entry of the evicted folio.
- *
- * Calculates and evaluates the refault distance of the previously
- * evicted folio in the context of the node and the memcg whose memory
- * pressure caused the eviction.
+ * workingset_test_recent - tests if the shadow entry is for a folio that was
+ * recently evicted. Also fills in @workingset with the value unpacked from
+ * shadow.
+ * @shadow: the shadow entry to be tested.
+ * @file: whether the corresponding folio is from the file lru.
+ * @workingset: where the workingset value unpacked from shadow should
+ * be stored.
+ *
+ * Return: true if the shadow is for a recently evicted folio; false otherwise.
*/
-void workingset_refault(struct folio *folio, void *shadow)
+bool workingset_test_recent(void *shadow, bool file, bool *workingset)
{
- bool file = folio_is_file_lru(folio);
struct mem_cgroup *eviction_memcg;
struct lruvec *eviction_lruvec;
unsigned long refault_distance;
unsigned long workingset_size;
- struct pglist_data *pgdat;
- struct mem_cgroup *memcg;
- unsigned long eviction;
- struct lruvec *lruvec;
unsigned long refault;
- bool workingset;
int memcgid;
- long nr;
+ struct pglist_data *pgdat;
+ unsigned long eviction;
- if (lru_gen_enabled()) {
- lru_gen_refault(folio, shadow);
- return;
- }
+ if (lru_gen_enabled())
+ return lru_gen_test_recent(shadow, file, &eviction_lruvec, &eviction, workingset);
- unpack_shadow(shadow, &memcgid, &pgdat, &eviction, &workingset);
+ unpack_shadow(shadow, &memcgid, &pgdat, &eviction, workingset);
eviction <<= bucket_order;
- /* Flush stats (and potentially sleep) before holding RCU read lock */
- mem_cgroup_flush_stats_ratelimited();
-
- rcu_read_lock();
/*
* Look up the memcg associated with the stored ID. It might
* have been deleted since the folio's eviction.
*/
eviction_memcg = mem_cgroup_from_id(memcgid);
if (!mem_cgroup_disabled() && !eviction_memcg)
- goto out;
+ return false;
+
eviction_lruvec = mem_cgroup_lruvec(eviction_memcg, pgdat);
refault = atomic_long_read(&eviction_lruvec->nonresident_age);
refault_distance = (refault - eviction) & EVICTION_MASK;
/*
- * The activation decision for this folio is made at the level
- * where the eviction occurred, as that is where the LRU order
- * during folio reclaim is being determined.
- *
- * However, the cgroup that will own the folio is the one that
- * is actually experiencing the refault event.
- */
- nr = folio_nr_pages(folio);
- memcg = folio_memcg(folio);
- pgdat = folio_pgdat(folio);
- lruvec = mem_cgroup_lruvec(memcg, pgdat);
-
- mod_lruvec_state(lruvec, WORKINGSET_REFAULT_BASE + file, nr);
- /*
* Compare the distance to the existing workingset size. We
* don't activate pages that couldn't stay resident even if
* all the memory was available to the workingset. Whether
NR_INACTIVE_ANON);
}
}
- if (refault_distance > workingset_size)
+
+ return refault_distance <= workingset_size;
+}
+
+/**
+ * workingset_refault - Evaluate the refault of a previously evicted folio.
+ * @folio: The freshly allocated replacement folio.
+ * @shadow: Shadow entry of the evicted folio.
+ *
+ * Calculates and evaluates the refault distance of the previously
+ * evicted folio in the context of the node and the memcg whose memory
+ * pressure caused the eviction.
+ */
+void workingset_refault(struct folio *folio, void *shadow)
+{
+ bool file = folio_is_file_lru(folio);
+ struct pglist_data *pgdat;
+ struct mem_cgroup *memcg;
+ struct lruvec *lruvec;
+ bool workingset;
+ long nr;
+
+ if (lru_gen_enabled()) {
+ lru_gen_refault(folio, shadow);
+ return;
+ }
+
+ /* Flush stats (and potentially sleep) before holding RCU read lock */
+ mem_cgroup_flush_stats_ratelimited();
+
+ rcu_read_lock();
+
+ /*
+ * The activation decision for this folio is made at the level
+ * where the eviction occurred, as that is where the LRU order
+ * during folio reclaim is being determined.
+ *
+ * However, the cgroup that will own the folio is the one that
+ * is actually experiencing the refault event.
+ */
+ nr = folio_nr_pages(folio);
+ memcg = folio_memcg(folio);
+ pgdat = folio_pgdat(folio);
+ lruvec = mem_cgroup_lruvec(memcg, pgdat);
+
+ mod_lruvec_state(lruvec, WORKINGSET_REFAULT_BASE + file, nr);
+
+ if (!workingset_test_recent(shadow, file, &workingset))
goto out;
folio_set_active(folio);