[PATCH v2 3/9] mm/workingset: extend the workingset detection for anon LRU

From: js1304
Date: Thu Feb 20 2020 - 00:12:16 EST


From: Joonsoo Kim <iamjoonsoo.kim@xxxxxxx>

In the following patch, workingset detection will be applied to
anonymous LRU. To prepare it, this patch adds some code to
distinguish/handle the both LRUs.

Signed-off-by: Joonsoo Kim <iamjoonsoo.kim@xxxxxxx>
---
include/linux/mmzone.h | 14 +++++++++-----
mm/memcontrol.c | 12 ++++++++----
mm/vmscan.c | 15 ++++++++++-----
mm/vmstat.c | 6 ++++--
mm/workingset.c | 35 ++++++++++++++++++++++-------------
5 files changed, 53 insertions(+), 29 deletions(-)

diff --git a/include/linux/mmzone.h b/include/linux/mmzone.h
index 5334ad8..b78fd8c 100644
--- a/include/linux/mmzone.h
+++ b/include/linux/mmzone.h
@@ -220,8 +220,12 @@ enum node_stat_item {
NR_ISOLATED_ANON, /* Temporary isolated pages from anon lru */
NR_ISOLATED_FILE, /* Temporary isolated pages from file lru */
WORKINGSET_NODES,
- WORKINGSET_REFAULT,
- WORKINGSET_ACTIVATE,
+ WORKINGSET_REFAULT_BASE,
+ WORKINGSET_REFAULT_ANON = WORKINGSET_REFAULT_BASE,
+ WORKINGSET_REFAULT_FILE,
+ WORKINGSET_ACTIVATE_BASE,
+ WORKINGSET_ACTIVATE_ANON = WORKINGSET_ACTIVATE_BASE,
+ WORKINGSET_ACTIVATE_FILE,
WORKINGSET_RESTORE,
WORKINGSET_NODERECLAIM,
NR_ANON_MAPPED, /* Mapped anonymous pages */
@@ -304,10 +308,10 @@ enum lruvec_flags {
struct lruvec {
struct list_head lists[NR_LRU_LISTS];
struct zone_reclaim_stat reclaim_stat;
- /* Evictions & activations on the inactive file list */
- atomic_long_t inactive_age;
+ /* Evictions & activations on the inactive list */
+ atomic_long_t inactive_age[2];
/* Refaults at the time of last reclaim cycle */
- unsigned long refaults;
+ unsigned long refaults[2];
/* Various lruvec state flags (enum lruvec_flags) */
unsigned long flags;
#ifdef CONFIG_MEMCG
diff --git a/mm/memcontrol.c b/mm/memcontrol.c
index 6c83cf4..8f4473d 100644
--- a/mm/memcontrol.c
+++ b/mm/memcontrol.c
@@ -1431,10 +1431,14 @@ static char *memory_stat_format(struct mem_cgroup *memcg)
seq_buf_printf(&s, "%s %lu\n", vm_event_name(PGMAJFAULT),
memcg_events(memcg, PGMAJFAULT));

- seq_buf_printf(&s, "workingset_refault %lu\n",
- memcg_page_state(memcg, WORKINGSET_REFAULT));
- seq_buf_printf(&s, "workingset_activate %lu\n",
- memcg_page_state(memcg, WORKINGSET_ACTIVATE));
+ seq_buf_printf(&s, "workingset_refault_anon %lu\n",
+ memcg_page_state(memcg, WORKINGSET_REFAULT_ANON));
+ seq_buf_printf(&s, "workingset_refault_file %lu\n",
+ memcg_page_state(memcg, WORKINGSET_REFAULT_FILE));
+ seq_buf_printf(&s, "workingset_activate_anon %lu\n",
+ memcg_page_state(memcg, WORKINGSET_ACTIVATE_ANON));
+ seq_buf_printf(&s, "workingset_activate_file %lu\n",
+ memcg_page_state(memcg, WORKINGSET_ACTIVATE_FILE));
seq_buf_printf(&s, "workingset_nodereclaim %lu\n",
memcg_page_state(memcg, WORKINGSET_NODERECLAIM));

diff --git a/mm/vmscan.c b/mm/vmscan.c
index 4122a84..74c3ade 100644
--- a/mm/vmscan.c
+++ b/mm/vmscan.c
@@ -2735,7 +2735,10 @@ static bool shrink_node(pg_data_t *pgdat, struct scan_control *sc)
if (!sc->force_deactivate) {
unsigned long refaults;

- if (inactive_is_low(target_lruvec, LRU_INACTIVE_ANON))
+ refaults = lruvec_page_state(target_lruvec,
+ WORKINGSET_ACTIVATE_ANON);
+ if (refaults != target_lruvec->refaults[0] ||
+ inactive_is_low(target_lruvec, LRU_INACTIVE_ANON))
sc->may_deactivate |= DEACTIVATE_ANON;
else
sc->may_deactivate &= ~DEACTIVATE_ANON;
@@ -2746,8 +2749,8 @@ static bool shrink_node(pg_data_t *pgdat, struct scan_control *sc)
* rid of any stale active pages quickly.
*/
refaults = lruvec_page_state(target_lruvec,
- WORKINGSET_ACTIVATE);
- if (refaults != target_lruvec->refaults ||
+ WORKINGSET_ACTIVATE_FILE);
+ if (refaults != target_lruvec->refaults[1] ||
inactive_is_low(target_lruvec, LRU_INACTIVE_FILE))
sc->may_deactivate |= DEACTIVATE_FILE;
else
@@ -3026,8 +3029,10 @@ static void snapshot_refaults(struct mem_cgroup *target_memcg, pg_data_t *pgdat)
unsigned long refaults;

target_lruvec = mem_cgroup_lruvec(target_memcg, pgdat);
- refaults = lruvec_page_state(target_lruvec, WORKINGSET_ACTIVATE);
- target_lruvec->refaults = refaults;
+ refaults = lruvec_page_state(target_lruvec, WORKINGSET_ACTIVATE_ANON);
+ target_lruvec->refaults[0] = refaults;
+ refaults = lruvec_page_state(target_lruvec, WORKINGSET_ACTIVATE_FILE);
+ target_lruvec->refaults[1] = refaults;
}

/*
diff --git a/mm/vmstat.c b/mm/vmstat.c
index 78d5337..3cdf8e9 100644
--- a/mm/vmstat.c
+++ b/mm/vmstat.c
@@ -1146,8 +1146,10 @@ const char * const vmstat_text[] = {
"nr_isolated_anon",
"nr_isolated_file",
"workingset_nodes",
- "workingset_refault",
- "workingset_activate",
+ "workingset_refault_anon",
+ "workingset_refault_file",
+ "workingset_activate_anon",
+ "workingset_activate_file",
"workingset_restore",
"workingset_nodereclaim",
"nr_anon_pages",
diff --git a/mm/workingset.c b/mm/workingset.c
index 474186b..5fb8f85 100644
--- a/mm/workingset.c
+++ b/mm/workingset.c
@@ -15,6 +15,7 @@
#include <linux/dax.h>
#include <linux/fs.h>
#include <linux/mm.h>
+#include <linux/mm_inline.h>

/*
* Double CLOCK lists
@@ -156,7 +157,7 @@
*
* Implementation
*
- * For each node's file LRU lists, a counter for inactive evictions
+ * For each node's anon/file LRU lists, a counter for inactive evictions
* and activations is maintained (node->inactive_age).
*
* On eviction, a snapshot of this counter (along with some bits to
@@ -213,7 +214,8 @@ static void unpack_shadow(void *shadow, int *memcgidp, pg_data_t **pgdat,
*workingsetp = workingset;
}

-static void advance_inactive_age(struct mem_cgroup *memcg, pg_data_t *pgdat)
+static void advance_inactive_age(struct mem_cgroup *memcg, pg_data_t *pgdat,
+ int is_file)
{
/*
* Reclaiming a cgroup means reclaiming all its children in a
@@ -230,7 +232,7 @@ static void advance_inactive_age(struct mem_cgroup *memcg, pg_data_t *pgdat)
struct lruvec *lruvec;

lruvec = mem_cgroup_lruvec(memcg, pgdat);
- atomic_long_inc(&lruvec->inactive_age);
+ atomic_long_inc(&lruvec->inactive_age[is_file]);
} while (memcg && (memcg = parent_mem_cgroup(memcg)));
}

@@ -248,18 +250,19 @@ void *workingset_eviction(struct page *page, struct mem_cgroup *target_memcg)
unsigned long eviction;
struct lruvec *lruvec;
int memcgid;
+ int is_file = page_is_file_cache(page);

/* Page is fully exclusive and pins page->mem_cgroup */
VM_BUG_ON_PAGE(PageLRU(page), page);
VM_BUG_ON_PAGE(page_count(page), page);
VM_BUG_ON_PAGE(!PageLocked(page), page);

- advance_inactive_age(page_memcg(page), pgdat);
+ advance_inactive_age(page_memcg(page), pgdat, is_file);

lruvec = mem_cgroup_lruvec(target_memcg, pgdat);
/* XXX: target_memcg can be NULL, go through lruvec */
memcgid = mem_cgroup_id(lruvec_memcg(lruvec));
- eviction = atomic_long_read(&lruvec->inactive_age);
+ eviction = atomic_long_read(&lruvec->inactive_age[is_file]);
return pack_shadow(memcgid, pgdat, eviction, PageWorkingset(page));
}

@@ -278,13 +281,16 @@ void workingset_refault(struct page *page, void *shadow)
struct lruvec *eviction_lruvec;
unsigned long refault_distance;
struct pglist_data *pgdat;
- unsigned long active_file;
+ unsigned long active;
struct mem_cgroup *memcg;
unsigned long eviction;
struct lruvec *lruvec;
unsigned long refault;
bool workingset;
int memcgid;
+ int is_file = page_is_file_cache(page);
+ enum lru_list active_lru = page_lru_base_type(page) + LRU_ACTIVE;
+ enum node_stat_item workingset_stat;

unpack_shadow(shadow, &memcgid, &pgdat, &eviction, &workingset);

@@ -309,8 +315,8 @@ void workingset_refault(struct page *page, void *shadow)
if (!mem_cgroup_disabled() && !eviction_memcg)
goto out;
eviction_lruvec = mem_cgroup_lruvec(eviction_memcg, pgdat);
- refault = atomic_long_read(&eviction_lruvec->inactive_age);
- active_file = lruvec_page_state(eviction_lruvec, NR_ACTIVE_FILE);
+ refault = atomic_long_read(&eviction_lruvec->inactive_age[is_file]);
+ active = lruvec_page_state(eviction_lruvec, active_lru);

/*
* Calculate the refault distance
@@ -341,19 +347,21 @@ void workingset_refault(struct page *page, void *shadow)
memcg = page_memcg(page);
lruvec = mem_cgroup_lruvec(memcg, pgdat);

- inc_lruvec_state(lruvec, WORKINGSET_REFAULT);
+ workingset_stat = WORKINGSET_REFAULT_BASE + is_file;
+ inc_lruvec_state(lruvec, workingset_stat);

/*
* Compare the distance to the existing workingset size. We
* don't act on pages that couldn't stay resident even if all
* the memory was available to the page cache.
*/
- if (refault_distance > active_file)
+ if (refault_distance > active)
goto out;

SetPageActive(page);
- advance_inactive_age(memcg, pgdat);
- inc_lruvec_state(lruvec, WORKINGSET_ACTIVATE);
+ advance_inactive_age(memcg, pgdat, is_file);
+ workingset_stat = WORKINGSET_ACTIVATE_BASE + is_file;
+ inc_lruvec_state(lruvec, workingset_stat);

/* Page was active prior to eviction */
if (workingset) {
@@ -371,6 +379,7 @@ void workingset_refault(struct page *page, void *shadow)
void workingset_activation(struct page *page)
{
struct mem_cgroup *memcg;
+ int is_file = page_is_file_cache(page);

rcu_read_lock();
/*
@@ -383,7 +392,7 @@ void workingset_activation(struct page *page)
memcg = page_memcg_rcu(page);
if (!mem_cgroup_disabled() && !memcg)
goto out;
- advance_inactive_age(memcg, page_pgdat(page));
+ advance_inactive_age(memcg, page_pgdat(page), is_file);
out:
rcu_read_unlock();
}
--
2.7.4