Merge tag 'y2038-alsa-v8-signed' of git://git.kernel.org:/pub/scm/linux/kernel/git...

[linux.git] / mm / workingset.c

diff --git a/mm/workingset.c b/mm/workingset.c
index c963831d354f8058447888c049c41178fe9a4d55..474186b76ceda30d04d0ca8fe4fd70f72ed76a4a 100644 (file)
--- a/mm/workingset.c
+++ b/mm/workingset.c
@@ -213,28 +213,53 @@ 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)
+{
+       /*
+        * Reclaiming a cgroup means reclaiming all its children in a
+        * round-robin fashion. That means that each cgroup has an LRU
+        * order that is composed of the LRU orders of its child
+        * cgroups; and every page has an LRU position not just in the
+        * cgroup that owns it, but in all of that group's ancestors.
+        *
+        * So when the physical inactive list of a leaf cgroup ages,
+        * the virtual inactive lists of all its parents, including
+        * the root cgroup's, age as well.
+        */
+       do {
+               struct lruvec *lruvec;
+
+               lruvec = mem_cgroup_lruvec(memcg, pgdat);
+               atomic_long_inc(&lruvec->inactive_age);
+       } while (memcg && (memcg = parent_mem_cgroup(memcg)));
+}
+
 /**
  * workingset_eviction - note the eviction of a page from memory
+ * @target_memcg: the cgroup that is causing the reclaim
  * @page: the page being evicted
  *
  * Returns a shadow entry to be stored in @page->mapping->i_pages in place
  * of the evicted @page so that a later refault can be detected.
  */
-void *workingset_eviction(struct page *page)
+void *workingset_eviction(struct page *page, struct mem_cgroup *target_memcg)
 {
        struct pglist_data *pgdat = page_pgdat(page);
-       struct mem_cgroup *memcg = page_memcg(page);
-       int memcgid = mem_cgroup_id(memcg);
        unsigned long eviction;
        struct lruvec *lruvec;
+       int memcgid;
 
        /* 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);
 
-       lruvec = mem_cgroup_lruvec(pgdat, memcg);
-       eviction = atomic_long_inc_return(&lruvec->inactive_age);
+       advance_inactive_age(page_memcg(page), pgdat);
+
+       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);
        return pack_shadow(memcgid, pgdat, eviction, PageWorkingset(page));
 }
 
@@ -244,10 +269,13 @@ void *workingset_eviction(struct page *page)
  * @shadow: shadow entry of the evicted page
  *
  * Calculates and evaluates the refault distance of the previously
- * evicted page in the context of the node it was allocated in.
+ * evicted page in the context of the node and the memcg whose memory
+ * pressure caused the eviction.
  */
 void workingset_refault(struct page *page, void *shadow)
 {
+       struct mem_cgroup *eviction_memcg;
+       struct lruvec *eviction_lruvec;
        unsigned long refault_distance;
        struct pglist_data *pgdat;
        unsigned long active_file;
@@ -277,12 +305,12 @@ void workingset_refault(struct page *page, void *shadow)
         * would be better if the root_mem_cgroup existed in all
         * configurations instead.
         */
-       memcg = mem_cgroup_from_id(memcgid);
-       if (!mem_cgroup_disabled() && !memcg)
+       eviction_memcg = mem_cgroup_from_id(memcgid);
+       if (!mem_cgroup_disabled() && !eviction_memcg)
                goto out;
-       lruvec = mem_cgroup_lruvec(pgdat, memcg);
-       refault = atomic_long_read(&lruvec->inactive_age);
-       active_file = lruvec_lru_size(lruvec, LRU_ACTIVE_FILE, MAX_NR_ZONES);
+       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);
 
        /*
         * Calculate the refault distance
@@ -302,6 +330,17 @@ void workingset_refault(struct page *page, void *shadow)
         */
        refault_distance = (refault - eviction) & EVICTION_MASK;
 
+       /*
+        * The activation decision for this page is made at the level
+        * where the eviction occurred, as that is where the LRU order
+        * during page reclaim is being determined.
+        *
+        * However, the cgroup that will own the page is the one that
+        * is actually experiencing the refault event.
+        */
+       memcg = page_memcg(page);
+       lruvec = mem_cgroup_lruvec(memcg, pgdat);
+
        inc_lruvec_state(lruvec, WORKINGSET_REFAULT);
 
        /*
@@ -313,7 +352,7 @@ void workingset_refault(struct page *page, void *shadow)
                goto out;
 
        SetPageActive(page);
-       atomic_long_inc(&lruvec->inactive_age);
+       advance_inactive_age(memcg, pgdat);
        inc_lruvec_state(lruvec, WORKINGSET_ACTIVATE);
 
        /* Page was active prior to eviction */
@@ -332,7 +371,6 @@ void workingset_refault(struct page *page, void *shadow)
 void workingset_activation(struct page *page)
 {
        struct mem_cgroup *memcg;
-       struct lruvec *lruvec;
 
        rcu_read_lock();
        /*
@@ -345,8 +383,7 @@ void workingset_activation(struct page *page)
        memcg = page_memcg_rcu(page);
        if (!mem_cgroup_disabled() && !memcg)
                goto out;
-       lruvec = mem_cgroup_lruvec(page_pgdat(page), memcg);
-       atomic_long_inc(&lruvec->inactive_age);
+       advance_inactive_age(memcg, page_pgdat(page));
 out:
        rcu_read_unlock();
 }
@@ -426,7 +463,7 @@ static unsigned long count_shadow_nodes(struct shrinker *shrinker,
                struct lruvec *lruvec;
                int i;
 
-               lruvec = mem_cgroup_lruvec(NODE_DATA(sc->nid), sc->memcg);
+               lruvec = mem_cgroup_lruvec(sc->memcg, NODE_DATA(sc->nid));
                for (pages = 0, i = 0; i < NR_LRU_LISTS; i++)
                        pages += lruvec_page_state_local(lruvec,
                                                         NR_LRU_BASE + i);