[PATCH v5 2/8] mm/lru: replace pgdat lru_lock with lruvec lock

From: Alex Shi
Date: Tue Dec 10 2019 - 06:48:37 EST

This patchset move lru_lock into lruvec, give a lru_lock for each of
lruvec, thus bring a lru_lock for each of memcg per node.

This is the main patch to replace per node lru_lock with per memcg
lruvec lock.

We introduces function lock_page_lruvec, which will lock the page's
memcg and then memcg's lruvec->lru_lock. (Thanks Johannes Weiner,
Hugh Dickins and Konstantin Khlebnikov suggestion/reminder on them)

According to Daniel Jordan's suggestion, I run 208 'dd' with on 104
containers on a 2s * 26cores * HT box with a modefied case:
https://git.kernel.org/pub/scm/linux/kernel/git/wfg/vm-scalability.git/tree/case-lru-file-readtwice

With this and later patches, the readtwice performance increases about
80% with containers, but w/o memcg the readtwice performance drops
about 5%.(and another 5% drops with the last debug patch).

Signed-off-by: Alex Shi <alex.shi@xxxxxxxxxxxxxxxxx>
Cc: Johannes Weiner <hannes@xxxxxxxxxxx>
Cc: Michal Hocko <mhocko@xxxxxxxxxx>
Cc: Vladimir Davydov <vdavydov.dev@xxxxxxxxx>
Cc: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
Cc: Roman Gushchin <guro@xxxxxx>
Cc: Shakeel Butt <shakeelb@xxxxxxxxxx>
Cc: Chris Down <chris@xxxxxxxxxxxxxx>
Cc: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
Cc: Mel Gorman <mgorman@xxxxxxxxxxxxxxxxxxx>
Cc: Vlastimil Babka <vbabka@xxxxxxx>
Cc: Qian Cai <cai@xxxxxx>
Cc: Andrey Ryabinin <aryabinin@xxxxxxxxxxxxx>
Cc: "Kirill A. Shutemov" <kirill.shutemov@xxxxxxxxxxxxxxx>
Cc: "JÃrÃme Glisse" <jglisse@xxxxxxxxxx>
Cc: Andrea Arcangeli <aarcange@xxxxxxxxxx>
Cc: Yang Shi <yang.shi@xxxxxxxxxxxxxxxxx>
Cc: David Rientjes <rientjes@xxxxxxxxxx>
Cc: "Aneesh Kumar K.V" <aneesh.kumar@xxxxxxxxxxxxx>
Cc: swkhack <swkhack@xxxxxxxxx>
Cc: "Potyra, Stefan" <Stefan.Potyra@xxxxxxxxxxxxxx>
Cc: Mike Rapoport <rppt@xxxxxxxxxxxxxxxxxx>
Cc: Stephen Rothwell <sfr@xxxxxxxxxxxxxxxx>
Cc: Colin Ian King <colin.king@xxxxxxxxxxxxx>
Cc: Jason Gunthorpe <jgg@xxxxxxxx>
Cc: Mauro Carvalho Chehab <mchehab+samsung@xxxxxxxxxx>
Cc: Matthew Wilcox <willy@xxxxxxxxxxxxx>
Cc: Peng Fan <peng.fan@xxxxxxx>
Cc: Nikolay Borisov <nborisov@xxxxxxxx>
Cc: Ira Weiny <ira.weiny@xxxxxxxxx>
Cc: Kirill Tkhai <ktkhai@xxxxxxxxxxxxx>
Cc: Yafang Shao <laoar.shao@xxxxxxxxx>
Cc: Konstantin Khlebnikov <khlebnikov@xxxxxxxxxxxxxx>
Cc: Hugh Dickins <hughd@xxxxxxxxxx>
Cc: Tejun Heo <tj@xxxxxxxxxx>
Cc: linux-kernel@xxxxxxxxxxxxxxx
Cc: linux-mm@xxxxxxxxx
Cc: cgroups@xxxxxxxxxxxxxxx
---
include/linux/memcontrol.h | 27 ++++++++++++++++
include/linux/mmzone.h | 2 ++
mm/compaction.c | 55 +++++++++++++++++++++-----------
mm/huge_memory.c | 18 ++++-------
mm/memcontrol.c | 75 ++++++++++++++++++++++++++++++++-----------
mm/mlock.c | 32 +++++++++----------
mm/mmzone.c | 1 +
mm/page_idle.c | 7 ++--
mm/swap.c | 75 ++++++++++++++++++-------------------------
mm/vmscan.c | 79 ++++++++++++++++++++++++++--------------------
10 files changed, 221 insertions(+), 150 deletions(-)

diff --git a/include/linux/memcontrol.h b/include/linux/memcontrol.h
index 5b86287fa069..16449d9836ee 100644
--- a/include/linux/memcontrol.h
+++ b/include/linux/memcontrol.h
@@ -417,6 +417,10 @@ static inline struct lruvec *mem_cgroup_lruvec(struct mem_cgroup *memcg,
}

struct lruvec *mem_cgroup_page_lruvec(struct page *, struct pglist_data *);
+struct lruvec *lock_page_lruvec_irq(struct page *);
+struct lruvec *lock_page_lruvec_irqsave(struct page *, unsigned long*);
+void unlock_page_lruvec_irq(struct lruvec *);
+void unlock_page_lruvec_irqrestore(struct lruvec *, unsigned long);

struct mem_cgroup *mem_cgroup_from_task(struct task_struct *p);

@@ -900,6 +904,29 @@ static inline struct lruvec *mem_cgroup_page_lruvec(struct page *page,
{
return &pgdat->__lruvec;
}
+#define lock_page_lruvec_irq(page) \
+({ \
+ struct pglist_data *pgdat = page_pgdat(page); \
+ spin_lock_irq(&pgdat->__lruvec.lru_lock); \
+ &pgdat->__lruvec; \
+})
+
+#define lock_page_lruvec_irqsave(page, flagsp) \
+({ \
+ struct pglist_data *pgdat = page_pgdat(page); \
+ spin_lock_irqsave(&pgdat->__lruvec.lru_lock, *flagsp); \
+ &pgdat->__lruvec; \
+})
+
+#define unlock_page_lruvec_irq(lruvec) \
+({ \
+ spin_unlock_irq(&lruvec->lru_lock); \
+})
+
+#define unlock_page_lruvec_irqrestore(lruvec, flags) \
+({ \
+ spin_unlock_irqrestore(&lruvec->lru_lock, flags); \
+})

static inline bool mm_match_cgroup(struct mm_struct *mm,
struct mem_cgroup *memcg)
diff --git a/include/linux/mmzone.h b/include/linux/mmzone.h
index 07b784ffbb14..a13b8a602ee5 100644
--- a/include/linux/mmzone.h
+++ b/include/linux/mmzone.h
@@ -267,6 +267,8 @@ struct lruvec {
unsigned long refaults;
/* Various lruvec state flags (enum lruvec_flags) */
unsigned long flags;
+ /* per lruvec lru_lock for memcg */
+ spinlock_t lru_lock;
#ifdef CONFIG_MEMCG
struct pglist_data *pgdat;
#endif
diff --git a/mm/compaction.c b/mm/compaction.c
index d20816b21b55..0907eec3db84 100644
--- a/mm/compaction.c
+++ b/mm/compaction.c
@@ -787,7 +787,7 @@ static bool too_many_isolated(pg_data_t *pgdat)
unsigned long nr_scanned = 0, nr_isolated = 0;
struct lruvec *lruvec;
unsigned long flags = 0;
- bool locked = false;
+ struct lruvec *locked_lruvec = NULL;
struct page *page = NULL, *valid_page = NULL;
unsigned long start_pfn = low_pfn;
bool skip_on_failure = false;
@@ -847,11 +847,20 @@ static bool too_many_isolated(pg_data_t *pgdat)
* contention, to give chance to IRQs. Abort completely if
* a fatal signal is pending.
*/
- if (!(low_pfn % SWAP_CLUSTER_MAX)
- && compact_unlock_should_abort(&pgdat->lru_lock,
- flags, &locked, cc)) {
- low_pfn = 0;
- goto fatal_pending;
+ if (!(low_pfn % SWAP_CLUSTER_MAX)) {
+ if (locked_lruvec) {
+ unlock_page_lruvec_irqrestore(locked_lruvec, flags);
+ locked_lruvec = NULL;
+ }
+
+ if (fatal_signal_pending(current)) {
+ cc->contended = true;
+
+ low_pfn = 0;
+ goto fatal_pending;
+ }
+
+ cond_resched();
}

if (!pfn_valid_within(low_pfn))
@@ -920,10 +929,9 @@ static bool too_many_isolated(pg_data_t *pgdat)
*/
if (unlikely(__PageMovable(page)) &&
!PageIsolated(page)) {
- if (locked) {
- spin_unlock_irqrestore(&pgdat->lru_lock,
- flags);
- locked = false;
+ if (locked_lruvec) {
+ unlock_page_lruvec_irqrestore(locked_lruvec, flags);
+ locked_lruvec = NULL;
}

if (!isolate_movable_page(page, isolate_mode))
@@ -949,10 +957,20 @@ static bool too_many_isolated(pg_data_t *pgdat)
if (!(cc->gfp_mask & __GFP_FS) && page_mapping(page))
goto isolate_fail;

+ lruvec = mem_cgroup_page_lruvec(page, pgdat);
+
/* If we already hold the lock, we can skip some rechecking */
- if (!locked) {
- locked = compact_lock_irqsave(&pgdat->lru_lock,
- &flags, cc);
+ if (lruvec != locked_lruvec) {
+ struct mem_cgroup *memcg = lock_page_memcg(page);
+
+ if (locked_lruvec) {
+ unlock_page_lruvec_irqrestore(locked_lruvec, flags);
+ locked_lruvec = NULL;
+ }
+ /* reget lruvec with a locked memcg */
+ lruvec = mem_cgroup_lruvec(memcg, page_pgdat(page));
+ compact_lock_irqsave(&lruvec->lru_lock, &flags, cc);
+ locked_lruvec = lruvec;

/* Try get exclusive access under lock */
if (!skip_updated) {
@@ -976,7 +994,6 @@ static bool too_many_isolated(pg_data_t *pgdat)
}
}

- lruvec = mem_cgroup_page_lruvec(page, pgdat);

/* Try isolate the page */
if (__isolate_lru_page(page, isolate_mode) != 0)
@@ -1017,9 +1034,9 @@ static bool too_many_isolated(pg_data_t *pgdat)
* page anyway.
*/
if (nr_isolated) {
- if (locked) {
- spin_unlock_irqrestore(&pgdat->lru_lock, flags);
- locked = false;
+ if (locked_lruvec) {
+ unlock_page_lruvec_irqrestore(locked_lruvec, flags);
+ locked_lruvec = NULL;
}
putback_movable_pages(&cc->migratepages);
cc->nr_migratepages = 0;
@@ -1044,8 +1061,8 @@ static bool too_many_isolated(pg_data_t *pgdat)
low_pfn = end_pfn;

isolate_abort:
- if (locked)
- spin_unlock_irqrestore(&pgdat->lru_lock, flags);
+ if (locked_lruvec)
+ unlock_page_lruvec_irqrestore(locked_lruvec, flags);

/*
* Updated the cached scanner pfn once the pageblock has been scanned
diff --git a/mm/huge_memory.c b/mm/huge_memory.c
index 13cc93785006..ea76d2998fa9 100644
--- a/mm/huge_memory.c
+++ b/mm/huge_memory.c
@@ -2495,17 +2495,13 @@ static void __split_huge_page_tail(struct page *head, int tail,
}

static void __split_huge_page(struct page *page, struct list_head *list,
- pgoff_t end, unsigned long flags)
+ struct lruvec *lruvec, pgoff_t end, unsigned long flags)
{
struct page *head = compound_head(page);
- pg_data_t *pgdat = page_pgdat(head);
- struct lruvec *lruvec;
struct address_space *swap_cache = NULL;
unsigned long offset = 0;
int i;

- lruvec = mem_cgroup_page_lruvec(head, pgdat);
-
/* complete memcg works before add pages to LRU */
mem_cgroup_split_huge_fixup(head);

@@ -2554,7 +2550,7 @@ static void __split_huge_page(struct page *page, struct list_head *list,
xa_unlock(&head->mapping->i_pages);
}

- spin_unlock_irqrestore(&pgdat->lru_lock, flags);
+ unlock_page_lruvec_irqrestore(lruvec, flags);

remap_page(head);

@@ -2693,13 +2689,13 @@ bool can_split_huge_page(struct page *page, int *pextra_pins)
int split_huge_page_to_list(struct page *page, struct list_head *list)
{
struct page *head = compound_head(page);
- struct pglist_data *pgdata = NODE_DATA(page_to_nid(head));
struct deferred_split *ds_queue = get_deferred_split_queue(page);
struct anon_vma *anon_vma = NULL;
struct address_space *mapping = NULL;
+ struct lruvec *lruvec;
int count, mapcount, extra_pins, ret;
bool mlocked;
- unsigned long flags;
+ unsigned long uninitialized_var(flags);
pgoff_t end;

VM_BUG_ON_PAGE(is_huge_zero_page(page), page);
@@ -2766,7 +2762,7 @@ int split_huge_page_to_list(struct page *page, struct list_head *list)
lru_add_drain();

/* prevent PageLRU to go away from under us, and freeze lru stats */
- spin_lock_irqsave(&pgdata->lru_lock, flags);
+ lruvec = lock_page_lruvec_irqsave(head, &flags);

if (mapping) {
XA_STATE(xas, &mapping->i_pages, page_index(head));
@@ -2797,7 +2793,7 @@ int split_huge_page_to_list(struct page *page, struct list_head *list)
}

spin_unlock(&ds_queue->split_queue_lock);
- __split_huge_page(page, list, end, flags);
+ __split_huge_page(page, list, lruvec, end, flags);
if (PageSwapCache(head)) {
swp_entry_t entry = { .val = page_private(head) };

@@ -2816,7 +2812,7 @@ int split_huge_page_to_list(struct page *page, struct list_head *list)
spin_unlock(&ds_queue->split_queue_lock);
fail: if (mapping)
xa_unlock(&mapping->i_pages);
- spin_unlock_irqrestore(&pgdata->lru_lock, flags);
+ unlock_page_lruvec_irqrestore(lruvec, flags);
remap_page(head);
ret = -EBUSY;
}
diff --git a/mm/memcontrol.c b/mm/memcontrol.c
index 62470325f9bc..4a92689c37d6 100644
--- a/mm/memcontrol.c
+++ b/mm/memcontrol.c
@@ -1210,11 +1210,11 @@ int mem_cgroup_scan_tasks(struct mem_cgroup *memcg,
* @page: the page
* @pgdat: pgdat of the page
*
- * This function is only safe when following the LRU page isolation
- * and putback protocol: the LRU lock must be held, and the page must
- * either be PageLRU() or the caller must have isolated/allocated it.
+ * The caller needs to grantee the page's mem_cgroup is undisturbed during
+ * using. That could be done by lock_page_memcg or lock_page_lruvec.
*/
-struct lruvec *mem_cgroup_page_lruvec(struct page *page, struct pglist_data *pgdat)
+struct lruvec *mem_cgroup_page_lruvec(struct page *page,
+ struct pglist_data *pgdat)
{
struct mem_cgroup_per_node *mz;
struct mem_cgroup *memcg;
@@ -1225,7 +1225,7 @@ struct lruvec *mem_cgroup_page_lruvec(struct page *page, struct pglist_data *pgd
goto out;
}

- memcg = page->mem_cgroup;
+ memcg = READ_ONCE(page->mem_cgroup);
/*
* Swapcache readahead pages are added to the LRU - and
* possibly migrated - before they are charged.
@@ -1246,6 +1246,42 @@ struct lruvec *mem_cgroup_page_lruvec(struct page *page, struct pglist_data *pgd
return lruvec;
}

+struct lruvec *lock_page_lruvec_irq(struct page *page)
+{
+ struct lruvec *lruvec;
+ struct mem_cgroup *memcg;
+
+ memcg = lock_page_memcg(page);
+ lruvec = mem_cgroup_lruvec(memcg, page_pgdat(page));
+ spin_lock_irq(&lruvec->lru_lock);
+
+ return lruvec;
+}
+
+struct lruvec *lock_page_lruvec_irqsave(struct page *page, unsigned long *flags)
+{
+ struct lruvec *lruvec;
+ struct mem_cgroup *memcg;
+
+ memcg = lock_page_memcg(page);
+ lruvec = mem_cgroup_lruvec(memcg, page_pgdat(page));
+ spin_lock_irqsave(&lruvec->lru_lock, *flags);
+
+ return lruvec;
+}
+
+void unlock_page_lruvec_irq(struct lruvec *lruvec)
+{
+ spin_unlock_irq(&lruvec->lru_lock);
+ __unlock_page_memcg(lruvec_memcg(lruvec));
+}
+
+void unlock_page_lruvec_irqrestore(struct lruvec *lruvec, unsigned long flags)
+{
+ spin_unlock_irqrestore(&lruvec->lru_lock, flags);
+ __unlock_page_memcg(lruvec_memcg(lruvec));
+}
+
/**
* mem_cgroup_update_lru_size - account for adding or removing an lru page
* @lruvec: mem_cgroup per zone lru vector
@@ -2571,41 +2607,42 @@ static void cancel_charge(struct mem_cgroup *memcg, unsigned int nr_pages)
css_put_many(&memcg->css, nr_pages);
}

-static void lock_page_lru(struct page *page, int *isolated)
+static struct lruvec *lock_page_lru(struct page *page, int *isolated)
{
- pg_data_t *pgdat = page_pgdat(page);
+ struct lruvec *lruvec = lock_page_lruvec_irq(page);

- spin_lock_irq(&pgdat->lru_lock);
if (PageLRU(page)) {
- struct lruvec *lruvec;

- lruvec = mem_cgroup_page_lruvec(page, pgdat);
ClearPageLRU(page);
del_page_from_lru_list(page, lruvec, page_lru(page));
*isolated = 1;
} else
*isolated = 0;
+
+ return lruvec;
}

-static void unlock_page_lru(struct page *page, int isolated)
+static void unlock_page_lru(struct page *page, int isolated,
+ struct lruvec *locked_lruvec)
{
- pg_data_t *pgdat = page_pgdat(page);
+ struct lruvec *lruvec;

- if (isolated) {
- struct lruvec *lruvec;
+ unlock_page_lruvec_irq(locked_lruvec);
+ lruvec = lock_page_lruvec_irq(page);

- lruvec = mem_cgroup_page_lruvec(page, pgdat);
+ if (isolated) {
VM_BUG_ON_PAGE(PageLRU(page), page);
SetPageLRU(page);
add_page_to_lru_list(page, lruvec, page_lru(page));
}
- spin_unlock_irq(&pgdat->lru_lock);
+ unlock_page_lruvec_irq(lruvec);
}

static void commit_charge(struct page *page, struct mem_cgroup *memcg,
bool lrucare)
{
int isolated;
+ struct lruvec *lruvec;

VM_BUG_ON_PAGE(page->mem_cgroup, page);

@@ -2614,7 +2651,7 @@ static void commit_charge(struct page *page, struct mem_cgroup *memcg,
* may already be on some other mem_cgroup's LRU. Take care of it.
*/
if (lrucare)
- lock_page_lru(page, &isolated);
+ lruvec = lock_page_lru(page, &isolated);

/*
* Nobody should be changing or seriously looking at
@@ -2633,7 +2670,7 @@ static void commit_charge(struct page *page, struct mem_cgroup *memcg,
page->mem_cgroup = memcg;

if (lrucare)
- unlock_page_lru(page, isolated);
+ unlock_page_lru(page, isolated, lruvec);
}

#ifdef CONFIG_MEMCG_KMEM
@@ -2929,7 +2966,7 @@ void __memcg_kmem_uncharge(struct page *page, int order)

/*
* Because tail pages are not marked as "used", set it. We're under
- * pgdat->lru_lock and migration entries setup in all page mappings.
+ * lruvec->lru_lock and migration entries setup in all page mappings.
*/
void mem_cgroup_split_huge_fixup(struct page *head)
{
diff --git a/mm/mlock.c b/mm/mlock.c
index a72c1eeded77..10d15f58b061 100644
--- a/mm/mlock.c
+++ b/mm/mlock.c
@@ -106,12 +106,10 @@ void mlock_vma_page(struct page *page)
* Isolate a page from LRU with optional get_page() pin.
* Assumes lru_lock already held and page already pinned.
*/
-static bool __munlock_isolate_lru_page(struct page *page, bool getpage)
+static bool __munlock_isolate_lru_page(struct page *page,
+ struct lruvec *lruvec, bool getpage)
{
if (PageLRU(page)) {
- struct lruvec *lruvec;
-
- lruvec = mem_cgroup_page_lruvec(page, page_pgdat(page));
if (getpage)
get_page(page);
ClearPageLRU(page);
@@ -182,7 +180,7 @@ static void __munlock_isolation_failed(struct page *page)
unsigned int munlock_vma_page(struct page *page)
{
int nr_pages;
- pg_data_t *pgdat = page_pgdat(page);
+ struct lruvec *lruvec;

/* For try_to_munlock() and to serialize with page migration */
BUG_ON(!PageLocked(page));
@@ -194,7 +192,7 @@ unsigned int munlock_vma_page(struct page *page)
* might otherwise copy PageMlocked to part of the tail pages before
* we clear it in the head page. It also stabilizes hpage_nr_pages().
*/
- spin_lock_irq(&pgdat->lru_lock);
+ lruvec = lock_page_lruvec_irq(page);

if (!TestClearPageMlocked(page)) {
/* Potentially, PTE-mapped THP: do not skip the rest PTEs */
@@ -205,15 +203,15 @@ unsigned int munlock_vma_page(struct page *page)
nr_pages = hpage_nr_pages(page);
__mod_zone_page_state(page_zone(page), NR_MLOCK, -nr_pages);

- if (__munlock_isolate_lru_page(page, true)) {
- spin_unlock_irq(&pgdat->lru_lock);
+ if (__munlock_isolate_lru_page(page, lruvec, true)) {
+ unlock_page_lruvec_irq(lruvec);
__munlock_isolated_page(page);
goto out;
}
__munlock_isolation_failed(page);

unlock_out:
- spin_unlock_irq(&pgdat->lru_lock);
+ unlock_page_lruvec_irq(lruvec);

out:
return nr_pages - 1;
@@ -291,28 +289,29 @@ static void __munlock_pagevec(struct pagevec *pvec, struct zone *zone)
{
int i;
int nr = pagevec_count(pvec);
- int delta_munlocked = -nr;
struct pagevec pvec_putback;
+ struct lruvec *lruvec = NULL;
int pgrescued = 0;

pagevec_init(&pvec_putback);

/* Phase 1: page isolation */
- spin_lock_irq(&zone->zone_pgdat->lru_lock);
for (i = 0; i < nr; i++) {
struct page *page = pvec->pages[i];

+ lruvec = lock_page_lruvec_irq(page);
+
if (TestClearPageMlocked(page)) {
/*
* We already have pin from follow_page_mask()
* so we can spare the get_page() here.
*/
- if (__munlock_isolate_lru_page(page, false))
+ if (__munlock_isolate_lru_page(page, lruvec, false)) {
+ __mod_zone_page_state(zone, NR_MLOCK, -1);
+ unlock_page_lruvec_irq(lruvec);
continue;
- else
+ } else
__munlock_isolation_failed(page);
- } else {
- delta_munlocked++;
}

/*
@@ -323,9 +322,8 @@ static void __munlock_pagevec(struct pagevec *pvec, struct zone *zone)
*/
pagevec_add(&pvec_putback, pvec->pages[i]);
pvec->pages[i] = NULL;
+ unlock_page_lruvec_irq(lruvec);
}
- __mod_zone_page_state(zone, NR_MLOCK, delta_munlocked);
- spin_unlock_irq(&zone->zone_pgdat->lru_lock);

/* Now we can release pins of pages that we are not munlocking */
pagevec_release(&pvec_putback);
diff --git a/mm/mmzone.c b/mm/mmzone.c
index 4686fdc23bb9..3750a90ed4a0 100644
--- a/mm/mmzone.c
+++ b/mm/mmzone.c
@@ -91,6 +91,7 @@ void lruvec_init(struct lruvec *lruvec)
enum lru_list lru;

memset(lruvec, 0, sizeof(struct lruvec));
+ spin_lock_init(&lruvec->lru_lock);

for_each_lru(lru)
INIT_LIST_HEAD(&lruvec->lists[lru]);
diff --git a/mm/page_idle.c b/mm/page_idle.c
index 295512465065..d2d868ca2bf7 100644
--- a/mm/page_idle.c
+++ b/mm/page_idle.c
@@ -31,7 +31,7 @@
static struct page *page_idle_get_page(unsigned long pfn)
{
struct page *page;
- pg_data_t *pgdat;
+ struct lruvec *lruvec;

if (!pfn_valid(pfn))
return NULL;
@@ -41,13 +41,12 @@ static struct page *page_idle_get_page(unsigned long pfn)
!get_page_unless_zero(page))
return NULL;

- pgdat = page_pgdat(page);
- spin_lock_irq(&pgdat->lru_lock);
+ lruvec = lock_page_lruvec_irq(page);
if (unlikely(!PageLRU(page))) {
put_page(page);
page = NULL;
}
- spin_unlock_irq(&pgdat->lru_lock);
+ unlock_page_lruvec_irq(lruvec);
return page;
}

diff --git a/mm/swap.c b/mm/swap.c
index 5341ae93861f..97e108be4f92 100644
--- a/mm/swap.c
+++ b/mm/swap.c
@@ -60,16 +60,14 @@
static void __page_cache_release(struct page *page)
{
if (PageLRU(page)) {
- pg_data_t *pgdat = page_pgdat(page);
struct lruvec *lruvec;
- unsigned long flags;
+ unsigned long flags = 0;

- spin_lock_irqsave(&pgdat->lru_lock, flags);
- lruvec = mem_cgroup_page_lruvec(page, pgdat);
+ lruvec = lock_page_lruvec_irqsave(page, &flags);
VM_BUG_ON_PAGE(!PageLRU(page), page);
__ClearPageLRU(page);
del_page_from_lru_list(page, lruvec, page_off_lru(page));
- spin_unlock_irqrestore(&pgdat->lru_lock, flags);
+ unlock_page_lruvec_irqrestore(lruvec, flags);
}
__ClearPageWaiters(page);
}
@@ -192,26 +190,18 @@ static void pagevec_lru_move_fn(struct pagevec *pvec,
void *arg)
{
int i;
- struct pglist_data *pgdat = NULL;
- struct lruvec *lruvec;
+ struct lruvec *lruvec = NULL;
unsigned long flags = 0;

for (i = 0; i < pagevec_count(pvec); i++) {
struct page *page = pvec->pages[i];
- struct pglist_data *pagepgdat = page_pgdat(page);

- if (pagepgdat != pgdat) {
- if (pgdat)
- spin_unlock_irqrestore(&pgdat->lru_lock, flags);
- pgdat = pagepgdat;
- spin_lock_irqsave(&pgdat->lru_lock, flags);
- }
+ lruvec = lock_page_lruvec_irqsave(page, &flags);

- lruvec = mem_cgroup_page_lruvec(page, pgdat);
(*move_fn)(page, lruvec, arg);
+ unlock_page_lruvec_irqrestore(lruvec, flags);
}
- if (pgdat)
- spin_unlock_irqrestore(&pgdat->lru_lock, flags);
+
release_pages(pvec->pages, pvec->nr);
pagevec_reinit(pvec);
}
@@ -324,12 +314,12 @@ static inline void activate_page_drain(int cpu)

void activate_page(struct page *page)
{
- pg_data_t *pgdat = page_pgdat(page);
+ struct lruvec *lruvec;

page = compound_head(page);
- spin_lock_irq(&pgdat->lru_lock);
- __activate_page(page, mem_cgroup_page_lruvec(page, pgdat), NULL);
- spin_unlock_irq(&pgdat->lru_lock);
+ lruvec = lock_page_lruvec_irq(page);
+ __activate_page(page, lruvec, NULL);
+ unlock_page_lruvec_irq(lruvec);
}
#endif

@@ -780,8 +770,7 @@ void release_pages(struct page **pages, int nr)
{
int i;
LIST_HEAD(pages_to_free);
- struct pglist_data *locked_pgdat = NULL;
- struct lruvec *lruvec;
+ struct lruvec *lruvec = NULL;
unsigned long uninitialized_var(flags);
unsigned int uninitialized_var(lock_batch);

@@ -791,21 +780,20 @@ void release_pages(struct page **pages, int nr)
/*
* Make sure the IRQ-safe lock-holding time does not get
* excessive with a continuous string of pages from the
- * same pgdat. The lock is held only if pgdat != NULL.
+ * same lruvec. The lock is held only if lruvec != NULL.
*/
- if (locked_pgdat && ++lock_batch == SWAP_CLUSTER_MAX) {
- spin_unlock_irqrestore(&locked_pgdat->lru_lock, flags);
- locked_pgdat = NULL;
+ if (lruvec && ++lock_batch == SWAP_CLUSTER_MAX) {
+ unlock_page_lruvec_irqrestore(lruvec, flags);
+ lruvec = NULL;
}

if (is_huge_zero_page(page))
continue;

if (is_zone_device_page(page)) {
- if (locked_pgdat) {
- spin_unlock_irqrestore(&locked_pgdat->lru_lock,
- flags);
- locked_pgdat = NULL;
+ if (lruvec) {
+ unlock_page_lruvec_irqrestore(lruvec, flags);
+ lruvec = NULL;
}
/*
* ZONE_DEVICE pages that return 'false' from
@@ -822,27 +810,24 @@ void release_pages(struct page **pages, int nr)
continue;

if (PageCompound(page)) {
- if (locked_pgdat) {
- spin_unlock_irqrestore(&locked_pgdat->lru_lock, flags);
- locked_pgdat = NULL;
+ if (lruvec) {
+ unlock_page_lruvec_irqrestore(lruvec, flags);
+ lruvec = NULL;
}
__put_compound_page(page);
continue;
}

if (PageLRU(page)) {
- struct pglist_data *pgdat = page_pgdat(page);
+ struct lruvec *new_lruvec = mem_cgroup_page_lruvec(page, page_pgdat(page));

- if (pgdat != locked_pgdat) {
- if (locked_pgdat)
- spin_unlock_irqrestore(&locked_pgdat->lru_lock,
- flags);
+ if (new_lruvec != lruvec) {
+ if (lruvec)
+ unlock_page_lruvec_irqrestore(lruvec, flags);
lock_batch = 0;
- locked_pgdat = pgdat;
- spin_lock_irqsave(&locked_pgdat->lru_lock, flags);
+ lruvec = lock_page_lruvec_irqsave(page, &flags);
}

- lruvec = mem_cgroup_page_lruvec(page, locked_pgdat);
VM_BUG_ON_PAGE(!PageLRU(page), page);
__ClearPageLRU(page);
del_page_from_lru_list(page, lruvec, page_off_lru(page));
@@ -854,8 +839,8 @@ void release_pages(struct page **pages, int nr)

list_add(&page->lru, &pages_to_free);
}
- if (locked_pgdat)
- spin_unlock_irqrestore(&locked_pgdat->lru_lock, flags);
+ if (lruvec)
+ unlock_page_lruvec_irqrestore(lruvec, flags);

mem_cgroup_uncharge_list(&pages_to_free);
free_unref_page_list(&pages_to_free);
@@ -893,7 +878,7 @@ void lru_add_page_tail(struct page *page, struct page *page_tail,
VM_BUG_ON_PAGE(!PageHead(page), page);
VM_BUG_ON_PAGE(PageCompound(page_tail), page);
VM_BUG_ON_PAGE(PageLRU(page_tail), page);
- lockdep_assert_held(&lruvec_pgdat(lruvec)->lru_lock);
+ lockdep_assert_held(&lruvec->lru_lock);

if (!list)
SetPageLRU(page_tail);
diff --git a/mm/vmscan.c b/mm/vmscan.c
index 69fb9bd9ef49..f59cf96b9e38 100644
--- a/mm/vmscan.c
+++ b/mm/vmscan.c
@@ -1752,11 +1752,9 @@ int isolate_lru_page(struct page *page)
WARN_RATELIMIT(PageTail(page), "trying to isolate tail page");

if (PageLRU(page)) {
- pg_data_t *pgdat = page_pgdat(page);
struct lruvec *lruvec;

- spin_lock_irq(&pgdat->lru_lock);
- lruvec = mem_cgroup_page_lruvec(page, pgdat);
+ lruvec = lock_page_lruvec_irq(page);
if (PageLRU(page)) {
int lru = page_lru(page);
get_page(page);
@@ -1764,7 +1762,7 @@ int isolate_lru_page(struct page *page)
del_page_from_lru_list(page, lruvec, lru);
ret = 0;
}
- spin_unlock_irq(&pgdat->lru_lock);
+ unlock_page_lruvec_irq(lruvec);
}
return ret;
}
@@ -1829,7 +1827,6 @@ static int too_many_isolated(struct pglist_data *pgdat, int file,
static unsigned noinline_for_stack move_pages_to_lru(struct lruvec *lruvec,
struct list_head *list)
{
- struct pglist_data *pgdat = lruvec_pgdat(lruvec);
int nr_pages, nr_moved = 0;
LIST_HEAD(pages_to_free);
struct page *page;
@@ -1840,9 +1837,9 @@ static unsigned noinline_for_stack move_pages_to_lru(struct lruvec *lruvec,
VM_BUG_ON_PAGE(PageLRU(page), page);
list_del(&page->lru);
if (unlikely(!page_evictable(page))) {
- spin_unlock_irq(&pgdat->lru_lock);
+ spin_unlock_irq(&lruvec->lru_lock);
putback_lru_page(page);
- spin_lock_irq(&pgdat->lru_lock);
+ spin_lock_irq(&lruvec->lru_lock);
continue;
}
SetPageLRU(page);
@@ -1852,19 +1849,35 @@ static unsigned noinline_for_stack move_pages_to_lru(struct lruvec *lruvec,
__ClearPageActive(page);

if (unlikely(PageCompound(page))) {
- spin_unlock_irq(&pgdat->lru_lock);
+ spin_unlock_irq(&lruvec->lru_lock);
(*get_compound_page_dtor(page))(page);
- spin_lock_irq(&pgdat->lru_lock);
+ spin_lock_irq(&lruvec->lru_lock);
} else
list_add(&page->lru, &pages_to_free);
} else {
- lruvec = mem_cgroup_page_lruvec(page, pgdat);
+ struct mem_cgroup *memcg = lock_page_memcg(page);
+ struct lruvec *plv;
+ bool relocked = false;
+
+ plv = mem_cgroup_lruvec(memcg, page_pgdat(page));
+ /* page's lruvec changed in memcg moving */
+ if (plv != lruvec) {
+ spin_unlock_irq(&lruvec->lru_lock);
+ spin_lock_irq(&plv->lru_lock);
+ relocked = true;
+ }
+
lru = page_lru(page);
nr_pages = hpage_nr_pages(page);
-
- update_lru_size(lruvec, lru, page_zonenum(page), nr_pages);
- list_add(&page->lru, &lruvec->lists[lru]);
+ update_lru_size(plv, lru, page_zonenum(page), nr_pages);
+ list_add(&page->lru, &plv->lists[lru]);
nr_moved += nr_pages;
+
+ if (relocked) {
+ spin_unlock_irq(&plv->lru_lock);
+ spin_lock_irq(&lruvec->lru_lock);
+ }
+ __unlock_page_memcg(memcg);
}
}

@@ -1923,7 +1936,7 @@ static int current_may_throttle(void)

lru_add_drain();

- spin_lock_irq(&pgdat->lru_lock);
+ spin_lock_irq(&lruvec->lru_lock);

nr_taken = isolate_lru_pages(nr_to_scan, lruvec, &page_list,
&nr_scanned, sc, lru);
@@ -1935,15 +1948,14 @@ static int current_may_throttle(void)
if (!cgroup_reclaim(sc))
__count_vm_events(item, nr_scanned);
__count_memcg_events(lruvec_memcg(lruvec), item, nr_scanned);
- spin_unlock_irq(&pgdat->lru_lock);
-
+ spin_unlock_irq(&lruvec->lru_lock);
if (nr_taken == 0)
return 0;

nr_reclaimed = shrink_page_list(&page_list, pgdat, sc, 0,
&stat, false);

- spin_lock_irq(&pgdat->lru_lock);
+ spin_lock_irq(&lruvec->lru_lock);

item = current_is_kswapd() ? PGSTEAL_KSWAPD : PGSTEAL_DIRECT;
if (!cgroup_reclaim(sc))
@@ -1956,7 +1968,7 @@ static int current_may_throttle(void)

__mod_node_page_state(pgdat, NR_ISOLATED_ANON + file, -nr_taken);

- spin_unlock_irq(&pgdat->lru_lock);
+ spin_unlock_irq(&lruvec->lru_lock);

mem_cgroup_uncharge_list(&page_list);
free_unref_page_list(&page_list);
@@ -2009,7 +2021,7 @@ static void shrink_active_list(unsigned long nr_to_scan,

lru_add_drain();

- spin_lock_irq(&pgdat->lru_lock);
+ spin_lock_irq(&lruvec->lru_lock);

nr_taken = isolate_lru_pages(nr_to_scan, lruvec, &l_hold,
&nr_scanned, sc, lru);
@@ -2020,7 +2032,7 @@ static void shrink_active_list(unsigned long nr_to_scan,
__count_vm_events(PGREFILL, nr_scanned);
__count_memcg_events(lruvec_memcg(lruvec), PGREFILL, nr_scanned);

- spin_unlock_irq(&pgdat->lru_lock);
+ spin_unlock_irq(&lruvec->lru_lock);

while (!list_empty(&l_hold)) {
cond_resched();
@@ -2066,7 +2078,7 @@ static void shrink_active_list(unsigned long nr_to_scan,
/*
* Move pages back to the lru list.
*/
- spin_lock_irq(&pgdat->lru_lock);
+ spin_lock_irq(&lruvec->lru_lock);
/*
* Count referenced pages from currently used mappings as rotated,
* even though only some of them are actually re-activated. This
@@ -2084,7 +2096,7 @@ static void shrink_active_list(unsigned long nr_to_scan,
__count_memcg_events(lruvec_memcg(lruvec), PGDEACTIVATE, nr_deactivate);

__mod_node_page_state(pgdat, NR_ISOLATED_ANON + file, -nr_taken);
- spin_unlock_irq(&pgdat->lru_lock);
+ spin_unlock_irq(&lruvec->lru_lock);

mem_cgroup_uncharge_list(&l_active);
free_unref_page_list(&l_active);
@@ -2369,7 +2381,7 @@ static void get_scan_count(struct lruvec *lruvec, struct scan_control *sc,
file = lruvec_lru_size(lruvec, LRU_ACTIVE_FILE, MAX_NR_ZONES) +
lruvec_lru_size(lruvec, LRU_INACTIVE_FILE, MAX_NR_ZONES);

- spin_lock_irq(&pgdat->lru_lock);
+ spin_lock_irq(&lruvec->lru_lock);
if (unlikely(reclaim_stat->recent_scanned[0] > anon / 4)) {
reclaim_stat->recent_scanned[0] /= 2;
reclaim_stat->recent_rotated[0] /= 2;
@@ -2390,7 +2402,7 @@ static void get_scan_count(struct lruvec *lruvec, struct scan_control *sc,

fp = file_prio * (reclaim_stat->recent_scanned[1] + 1);
fp /= reclaim_stat->recent_rotated[1] + 1;
- spin_unlock_irq(&pgdat->lru_lock);
+ spin_unlock_irq(&lruvec->lru_lock);

fraction[0] = ap;
fraction[1] = fp;
@@ -4283,24 +4295,21 @@ int page_evictable(struct page *page)
*/
void check_move_unevictable_pages(struct pagevec *pvec)
{
- struct lruvec *lruvec;
- struct pglist_data *pgdat = NULL;
+ struct lruvec *lruvec = NULL;
int pgscanned = 0;
int pgrescued = 0;
int i;

for (i = 0; i < pvec->nr; i++) {
struct page *page = pvec->pages[i];
- struct pglist_data *pagepgdat = page_pgdat(page);
+ struct lruvec *new_lruvec = mem_cgroup_page_lruvec(page, page_pgdat(page));

pgscanned++;
- if (pagepgdat != pgdat) {
- if (pgdat)
- spin_unlock_irq(&pgdat->lru_lock);
- pgdat = pagepgdat;
- spin_lock_irq(&pgdat->lru_lock);
+ if (lruvec != new_lruvec) {
+ if (lruvec)
+ unlock_page_lruvec_irq(lruvec);
+ lruvec = lock_page_lruvec_irq(page);
}
- lruvec = mem_cgroup_page_lruvec(page, pgdat);

if (!PageLRU(page) || !PageUnevictable(page))
continue;
@@ -4316,10 +4325,10 @@ void check_move_unevictable_pages(struct pagevec *pvec)
}
}

- if (pgdat) {
+ if (lruvec) {
__count_vm_events(UNEVICTABLE_PGRESCUED, pgrescued);
__count_vm_events(UNEVICTABLE_PGSCANNED, pgscanned);
- spin_unlock_irq(&pgdat->lru_lock);
+ unlock_page_lruvec_irq(lruvec);
}
}
EXPORT_SYMBOL_GPL(check_move_unevictable_pages);
--
1.8.3.1