* + mm-lru-replace-pgdat-lru_lock-with-lruvec-lock.patch added to -mm tree
@ 2020-11-16 21:57 akpm
2020-11-19 6:26 ` Alex Shi
0 siblings, 1 reply; 2+ messages in thread
From: akpm @ 2020-11-16 21:57 UTC (permalink / raw)
To: aarcange, alex.shi, alexander.duyck, aryabinin, daniel.m.jordan,
hannes, hughd, iamjoonsoo.kim, jannh, khlebnikov,
kirill.shutemov, kirill, mgorman, mhocko, mhocko, mika.penttila,
minchan, mm-commits, richard.weiyang, rong.a.chen, shakeelb,
tglx, tj, vbabka, vdavydov.dev, willy, yang.shi, ying.huang
The patch titled
Subject: mm/lru: replace pgdat lru_lock with lruvec lock
has been added to the -mm tree. Its filename is
mm-lru-replace-pgdat-lru_lock-with-lruvec-lock.patch
This patch should soon appear at
https://ozlabs.org/~akpm/mmots/broken-out/mm-lru-replace-pgdat-lru_lock-with-lruvec-lock.patch
and later at
https://ozlabs.org/~akpm/mmotm/broken-out/mm-lru-replace-pgdat-lru_lock-with-lruvec-lock.patch
Before you just go and hit "reply", please:
a) Consider who else should be cc'ed
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reply-to-all to that, adding suitable additional cc's
*** Remember to use Documentation/process/submit-checklist.rst when testing your code ***
The -mm tree is included into linux-next and is updated
there every 3-4 working days
------------------------------------------------------
From: Alex Shi <alex.shi@linux.alibaba.com>
Subject: mm/lru: replace pgdat lru_lock with lruvec lock
This patch moves per node lru_lock into lruvec, thus bring a lru_lock for
each of memcg per node. So on a large machine, each of memcg don't have
to suffer from per node pgdat->lru_lock competition. They could go fast
with their self lru_lock.
After move memcg charge before lru inserting, page isolation could
serialize page's memcg, then per memcg lruvec lock is stable and could
replace per node lru lock.
In isolate_migratepages_block(), compact_unlock_should_abort and
lock_page_lruvec_irqsave are open coded to work with compact_control.
Also add a debug func in locking which may give some clues if there are
sth out of hands.
Daniel Jordan's testing show 62% improvement on modified readtwice case on
his 2P * 10 core * 2 HT broadwell box.
https://lore.kernel.org/lkml/20200915165807.kpp7uhiw7l3loofu@ca-dmjordan1.us.oracle.com/
On a large machine with memcg enabled but not used, the page's lruvec
seeking pass a few pointers, that may lead to lru_lock holding time
increase and a bit regression.
Hugh Dickins helped on the patch polish, thanks!
Link: https://lkml.kernel.org/r/1604566549-62481-18-git-send-email-alex.shi@linux.alibaba.com
Signed-off-by: Alex Shi <alex.shi@linux.alibaba.com>
Acked-by: Hugh Dickins <hughd@google.com>
Acked-by: Johannes Weiner <hannes@cmpxchg.org>
Cc: Rong Chen <rong.a.chen@intel.com>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Vladimir Davydov <vdavydov.dev@gmail.com>
Cc: Yang Shi <yang.shi@linux.alibaba.com>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Konstantin Khlebnikov <khlebnikov@yandex-team.ru>
Cc: Daniel Jordan <daniel.m.jordan@oracle.com>
Cc: Alexander Duyck <alexander.duyck@gmail.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Andrey Ryabinin <aryabinin@virtuozzo.com>
Cc: "Huang, Ying" <ying.huang@intel.com>
Cc: Jann Horn <jannh@google.com>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Cc: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: Kirill A. Shutemov <kirill@shutemov.name>
Cc: Mel Gorman <mgorman@techsingularity.net>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Mika Penttilä <mika.penttila@nextfour.com>
Cc: Minchan Kim <minchan@kernel.org>
Cc: Shakeel Butt <shakeelb@google.com>
Cc: Tejun Heo <tj@kernel.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Wei Yang <richard.weiyang@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---
include/linux/memcontrol.h | 58 +++++++++++++++++
include/linux/mmzone.h | 3
mm/compaction.c | 56 ++++++++++------
mm/huge_memory.c | 11 +--
mm/memcontrol.c | 73 +++++++++++++++++++++-
mm/mlock.c | 22 ++++--
mm/mmzone.c | 1
mm/page_alloc.c | 1
mm/swap.c | 116 +++++++++++++++++------------------
mm/vmscan.c | 55 +++++++---------
10 files changed, 270 insertions(+), 126 deletions(-)
--- a/include/linux/memcontrol.h~mm-lru-replace-pgdat-lru_lock-with-lruvec-lock
+++ a/include/linux/memcontrol.h
@@ -491,6 +491,19 @@ struct mem_cgroup *get_mem_cgroup_from_m
struct mem_cgroup *get_mem_cgroup_from_page(struct page *page);
+struct lruvec *lock_page_lruvec(struct page *page);
+struct lruvec *lock_page_lruvec_irq(struct page *page);
+struct lruvec *lock_page_lruvec_irqsave(struct page *page,
+ unsigned long *flags);
+
+#ifdef CONFIG_DEBUG_VM
+void lruvec_memcg_debug(struct lruvec *lruvec, struct page *page);
+#else
+static inline void lruvec_memcg_debug(struct lruvec *lruvec, struct page *page)
+{
+}
+#endif
+
static inline
struct mem_cgroup *mem_cgroup_from_css(struct cgroup_subsys_state *css){
return css ? container_of(css, struct mem_cgroup, css) : NULL;
@@ -1035,6 +1048,31 @@ static inline void mem_cgroup_put(struct
{
}
+static inline struct lruvec *lock_page_lruvec(struct page *page)
+{
+ struct pglist_data *pgdat = page_pgdat(page);
+
+ spin_lock(&pgdat->__lruvec.lru_lock);
+ return &pgdat->__lruvec;
+}
+
+static inline struct lruvec *lock_page_lruvec_irq(struct page *page)
+{
+ struct pglist_data *pgdat = page_pgdat(page);
+
+ spin_lock_irq(&pgdat->__lruvec.lru_lock);
+ return &pgdat->__lruvec;
+}
+
+static inline struct lruvec *lock_page_lruvec_irqsave(struct page *page,
+ unsigned long *flagsp)
+{
+ struct pglist_data *pgdat = page_pgdat(page);
+
+ spin_lock_irqsave(&pgdat->__lruvec.lru_lock, *flagsp);
+ return &pgdat->__lruvec;
+}
+
static inline struct mem_cgroup *
mem_cgroup_iter(struct mem_cgroup *root,
struct mem_cgroup *prev,
@@ -1278,6 +1316,10 @@ static inline
void count_memcg_event_mm(struct mm_struct *mm, enum vm_event_item idx)
{
}
+
+static inline void lruvec_memcg_debug(struct lruvec *lruvec, struct page *page)
+{
+}
#endif /* CONFIG_MEMCG */
/* idx can be of type enum memcg_stat_item or node_stat_item */
@@ -1407,6 +1449,22 @@ static inline struct lruvec *parent_lruv
return mem_cgroup_lruvec(memcg, lruvec_pgdat(lruvec));
}
+static inline void unlock_page_lruvec(struct lruvec *lruvec)
+{
+ spin_unlock(&lruvec->lru_lock);
+}
+
+static inline void unlock_page_lruvec_irq(struct lruvec *lruvec)
+{
+ spin_unlock_irq(&lruvec->lru_lock);
+}
+
+static inline void unlock_page_lruvec_irqrestore(struct lruvec *lruvec,
+ unsigned long flags)
+{
+ spin_unlock_irqrestore(&lruvec->lru_lock, flags);
+}
+
#ifdef CONFIG_CGROUP_WRITEBACK
struct wb_domain *mem_cgroup_wb_domain(struct bdi_writeback *wb);
--- a/include/linux/mmzone.h~mm-lru-replace-pgdat-lru_lock-with-lruvec-lock
+++ a/include/linux/mmzone.h
@@ -276,6 +276,8 @@ enum lruvec_flags {
struct lruvec {
struct list_head lists[NR_LRU_LISTS];
+ /* per lruvec lru_lock for memcg */
+ spinlock_t lru_lock;
/*
* These track the cost of reclaiming one LRU - file or anon -
* over the other. As the observed cost of reclaiming one LRU
@@ -796,7 +798,6 @@ typedef struct pglist_data {
/* Write-intensive fields used by page reclaim */
ZONE_PADDING(_pad1_)
- spinlock_t lru_lock;
#ifdef CONFIG_DEFERRED_STRUCT_PAGE_INIT
/*
--- a/mm/compaction.c~mm-lru-replace-pgdat-lru_lock-with-lruvec-lock
+++ a/mm/compaction.c
@@ -804,7 +804,7 @@ isolate_migratepages_block(struct compac
unsigned long nr_scanned = 0, nr_isolated = 0;
struct lruvec *lruvec;
unsigned long flags = 0;
- bool locked = false;
+ struct lruvec *locked = NULL;
struct page *page = NULL, *valid_page = NULL;
unsigned long start_pfn = low_pfn;
bool skip_on_failure = false;
@@ -868,11 +868,20 @@ isolate_migratepages_block(struct compac
* 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) {
+ unlock_page_lruvec_irqrestore(locked, flags);
+ locked = NULL;
+ }
+
+ if (fatal_signal_pending(current)) {
+ cc->contended = true;
+
+ low_pfn = 0;
+ goto fatal_pending;
+ }
+
+ cond_resched();
}
if (!pfn_valid_within(low_pfn))
@@ -944,9 +953,8 @@ isolate_migratepages_block(struct compac
if (unlikely(__PageMovable(page)) &&
!PageIsolated(page)) {
if (locked) {
- spin_unlock_irqrestore(&pgdat->lru_lock,
- flags);
- locked = false;
+ unlock_page_lruvec_irqrestore(locked, flags);
+ locked = NULL;
}
if (!isolate_movable_page(page, isolate_mode))
@@ -987,10 +995,19 @@ isolate_migratepages_block(struct compac
if (!TestClearPageLRU(page))
goto isolate_fail_put;
+ rcu_read_lock();
+ 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) {
+ if (locked)
+ unlock_page_lruvec_irqrestore(locked, flags);
+
+ compact_lock_irqsave(&lruvec->lru_lock, &flags, cc);
+ locked = lruvec;
+ rcu_read_unlock();
+
+ lruvec_memcg_debug(lruvec, page);
/* Try get exclusive access under lock */
if (!skip_updated) {
@@ -1009,9 +1026,8 @@ isolate_migratepages_block(struct compac
SetPageLRU(page);
goto isolate_fail_put;
}
- }
-
- lruvec = mem_cgroup_page_lruvec(page, pgdat);
+ } else
+ rcu_read_unlock();
/* The whole page is taken off the LRU; skip the tail pages. */
if (PageCompound(page))
@@ -1045,8 +1061,8 @@ isolate_success:
isolate_fail_put:
/* Avoid potential deadlock in freeing page under lru_lock */
if (locked) {
- spin_unlock_irqrestore(&pgdat->lru_lock, flags);
- locked = false;
+ unlock_page_lruvec_irqrestore(locked, flags);
+ locked = NULL;
}
put_page(page);
@@ -1061,8 +1077,8 @@ isolate_fail:
*/
if (nr_isolated) {
if (locked) {
- spin_unlock_irqrestore(&pgdat->lru_lock, flags);
- locked = false;
+ unlock_page_lruvec_irqrestore(locked, flags);
+ locked = NULL;
}
putback_movable_pages(&cc->migratepages);
cc->nr_migratepages = 0;
@@ -1090,7 +1106,7 @@ isolate_fail:
isolate_abort:
if (locked)
- spin_unlock_irqrestore(&pgdat->lru_lock, flags);
+ unlock_page_lruvec_irqrestore(locked, flags);
if (page) {
SetPageLRU(page);
put_page(page);
--- a/mm/huge_memory.c~mm-lru-replace-pgdat-lru_lock-with-lruvec-lock
+++ a/mm/huge_memory.c
@@ -2351,7 +2351,7 @@ static void lru_add_page_tail(struct pag
VM_BUG_ON_PAGE(!PageHead(head), head);
VM_BUG_ON_PAGE(PageCompound(tail), head);
VM_BUG_ON_PAGE(PageLRU(tail), head);
- lockdep_assert_held(&lruvec_pgdat(lruvec)->lru_lock);
+ lockdep_assert_held(&lruvec->lru_lock);
if (list) {
/* page reclaim is reclaiming a huge page */
@@ -2435,7 +2435,6 @@ static void __split_huge_page(struct pag
pgoff_t end)
{
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;
@@ -2453,10 +2452,8 @@ static void __split_huge_page(struct pag
xa_lock(&swap_cache->i_pages);
}
- /* prevent PageLRU to go away from under us, and freeze lru stats */
- spin_lock(&pgdat->lru_lock);
-
- lruvec = mem_cgroup_page_lruvec(head, pgdat);
+ /* lock lru list/PageCompound, ref freezed by page_ref_freeze */
+ lruvec = lock_page_lruvec(head);
for (i = nr - 1; i >= 1; i--) {
__split_huge_page_tail(head, i, lruvec, list);
@@ -2477,7 +2474,7 @@ static void __split_huge_page(struct pag
}
ClearPageCompound(head);
- spin_unlock(&pgdat->lru_lock);
+ unlock_page_lruvec(lruvec);
/* Caller disabled irqs, so they are still disabled here */
split_page_owner(head, nr);
--- a/mm/memcontrol.c~mm-lru-replace-pgdat-lru_lock-with-lruvec-lock
+++ a/mm/memcontrol.c
@@ -20,6 +20,9 @@
* Lockless page tracking & accounting
* Unified hierarchy configuration model
* Copyright (C) 2015 Red Hat, Inc., Johannes Weiner
+ *
+ * Per memcg lru locking
+ * Copyright (C) 2020 Alibaba, Inc, Alex Shi
*/
#include <linux/page_counter.h>
@@ -1312,6 +1315,19 @@ int mem_cgroup_scan_tasks(struct mem_cgr
return ret;
}
+#ifdef CONFIG_DEBUG_VM
+void lruvec_memcg_debug(struct lruvec *lruvec, struct page *page)
+{
+ if (mem_cgroup_disabled())
+ return;
+
+ if (!page->mem_cgroup)
+ VM_BUG_ON_PAGE(lruvec_memcg(lruvec) != root_mem_cgroup, page);
+ else
+ VM_BUG_ON_PAGE(lruvec_memcg(lruvec) != page->mem_cgroup, page);
+}
+#endif
+
/**
* mem_cgroup_page_lruvec - return lruvec for isolating/putting an LRU page
* @page: the page
@@ -1353,6 +1369,59 @@ out:
}
/**
+ * lock_page_lruvec - lock and return lruvec for a given page.
+ * @page: the page
+ *
+ * This series functions should be used in either conditions:
+ * PageLRU is cleared or unset
+ * or page is locked.
+ */
+struct lruvec *lock_page_lruvec(struct page *page)
+{
+ struct lruvec *lruvec;
+ struct pglist_data *pgdat = page_pgdat(page);
+
+ rcu_read_lock();
+ lruvec = mem_cgroup_page_lruvec(page, pgdat);
+ spin_lock(&lruvec->lru_lock);
+ rcu_read_unlock();
+
+ lruvec_memcg_debug(lruvec, page);
+
+ return lruvec;
+}
+
+struct lruvec *lock_page_lruvec_irq(struct page *page)
+{
+ struct lruvec *lruvec;
+ struct pglist_data *pgdat = page_pgdat(page);
+
+ rcu_read_lock();
+ lruvec = mem_cgroup_page_lruvec(page, pgdat);
+ spin_lock_irq(&lruvec->lru_lock);
+ rcu_read_unlock();
+
+ lruvec_memcg_debug(lruvec, page);
+
+ return lruvec;
+}
+
+struct lruvec *lock_page_lruvec_irqsave(struct page *page, unsigned long *flags)
+{
+ struct lruvec *lruvec;
+ struct pglist_data *pgdat = page_pgdat(page);
+
+ rcu_read_lock();
+ lruvec = mem_cgroup_page_lruvec(page, pgdat);
+ spin_lock_irqsave(&lruvec->lru_lock, *flags);
+ rcu_read_unlock();
+
+ lruvec_memcg_debug(lruvec, page);
+
+ return lruvec;
+}
+
+/**
* mem_cgroup_update_lru_size - account for adding or removing an lru page
* @lruvec: mem_cgroup per zone lru vector
* @lru: index of lru list the page is sitting on
@@ -3262,10 +3331,8 @@ void obj_cgroup_uncharge(struct obj_cgro
#endif /* CONFIG_MEMCG_KMEM */
#ifdef CONFIG_TRANSPARENT_HUGEPAGE
-
/*
- * Because tail pages are not marked as "used", set it. We're under
- * pgdat->lru_lock and migration entries setup in all page mappings.
+ * Because page->mem_cgroup is not set on compound tails, set it now.
*/
void mem_cgroup_split_huge_fixup(struct page *head)
{
--- a/mm/mlock.c~mm-lru-replace-pgdat-lru_lock-with-lruvec-lock
+++ a/mm/mlock.c
@@ -262,12 +262,12 @@ static void __munlock_pagevec(struct pag
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];
@@ -277,10 +277,16 @@ static void __munlock_pagevec(struct pag
* so we can spare the get_page() here.
*/
if (TestClearPageLRU(page)) {
- struct lruvec *lruvec;
+ struct lruvec *new_lruvec;
+
+ new_lruvec = mem_cgroup_page_lruvec(page,
+ page_pgdat(page));
+ if (new_lruvec != lruvec) {
+ if (lruvec)
+ unlock_page_lruvec_irq(lruvec);
+ lruvec = lock_page_lruvec_irq(page);
+ }
- lruvec = mem_cgroup_page_lruvec(page,
- page_pgdat(page));
del_page_from_lru_list(page, lruvec,
page_lru(page));
continue;
@@ -299,8 +305,12 @@ static void __munlock_pagevec(struct pag
pagevec_add(&pvec_putback, pvec->pages[i]);
pvec->pages[i] = NULL;
}
- __mod_zone_page_state(zone, NR_MLOCK, delta_munlocked);
- spin_unlock_irq(&zone->zone_pgdat->lru_lock);
+ if (lruvec) {
+ __mod_zone_page_state(zone, NR_MLOCK, delta_munlocked);
+ unlock_page_lruvec_irq(lruvec);
+ } else if (delta_munlocked) {
+ mod_zone_page_state(zone, NR_MLOCK, delta_munlocked);
+ }
/* Now we can release pins of pages that we are not munlocking */
pagevec_release(&pvec_putback);
--- a/mm/mmzone.c~mm-lru-replace-pgdat-lru_lock-with-lruvec-lock
+++ a/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]);
--- a/mm/page_alloc.c~mm-lru-replace-pgdat-lru_lock-with-lruvec-lock
+++ a/mm/page_alloc.c
@@ -6791,7 +6791,6 @@ static void __meminit pgdat_init_interna
init_waitqueue_head(&pgdat->pfmemalloc_wait);
pgdat_page_ext_init(pgdat);
- spin_lock_init(&pgdat->lru_lock);
lruvec_init(&pgdat->__lruvec);
}
--- a/mm/swap.c~mm-lru-replace-pgdat-lru_lock-with-lruvec-lock
+++ a/mm/swap.c
@@ -79,16 +79,14 @@ static DEFINE_PER_CPU(struct lru_pvecs,
static void __page_cache_release(struct page *page)
{
if (PageLRU(page)) {
- pg_data_t *pgdat = page_pgdat(page);
struct lruvec *lruvec;
unsigned long flags;
- 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);
}
@@ -207,32 +205,30 @@ static void pagevec_lru_move_fn(struct p
void (*move_fn)(struct page *page, struct lruvec *lruvec))
{
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);
- }
+ struct lruvec *new_lruvec;
/* block memcg migration during page moving between lru */
if (!TestClearPageLRU(page))
continue;
- lruvec = mem_cgroup_page_lruvec(page, pgdat);
+ new_lruvec = mem_cgroup_page_lruvec(page, page_pgdat(page));
+ if (lruvec != new_lruvec) {
+ if (lruvec)
+ unlock_page_lruvec_irqrestore(lruvec, flags);
+ lruvec = lock_page_lruvec_irqsave(page, &flags);
+ }
+
(*move_fn)(page, lruvec);
SetPageLRU(page);
}
- if (pgdat)
- spin_unlock_irqrestore(&pgdat->lru_lock, flags);
+ if (lruvec)
+ unlock_page_lruvec_irqrestore(lruvec, flags);
release_pages(pvec->pages, pvec->nr);
pagevec_reinit(pvec);
}
@@ -274,9 +270,15 @@ void lru_note_cost(struct lruvec *lruvec
{
do {
unsigned long lrusize;
- struct pglist_data *pgdat = lruvec_pgdat(lruvec);
- spin_lock_irq(&pgdat->lru_lock);
+ /*
+ * Hold lruvec->lru_lock is safe here, since
+ * 1) The pinned lruvec in reclaim, or
+ * 2) From a pre-LRU page during refault (which also holds the
+ * rcu lock, so would be safe even if the page was on the LRU
+ * and could move simultaneously to a new lruvec).
+ */
+ spin_lock_irq(&lruvec->lru_lock);
/* Record cost event */
if (file)
lruvec->file_cost += nr_pages;
@@ -300,7 +302,7 @@ void lru_note_cost(struct lruvec *lruvec
lruvec->file_cost /= 2;
lruvec->anon_cost /= 2;
}
- spin_unlock_irq(&pgdat->lru_lock);
+ spin_unlock_irq(&lruvec->lru_lock);
} while ((lruvec = parent_lruvec(lruvec)));
}
@@ -364,13 +366,15 @@ static inline void activate_page_drain(i
static 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);
- if (PageLRU(page))
- __activate_page(page, mem_cgroup_page_lruvec(page, pgdat));
- spin_unlock_irq(&pgdat->lru_lock);
+ if (TestClearPageLRU(page)) {
+ lruvec = lock_page_lruvec_irq(page);
+ __activate_page(page, lruvec);
+ unlock_page_lruvec_irq(lruvec);
+ SetPageLRU(page);
+ }
}
#endif
@@ -860,8 +864,7 @@ void release_pages(struct page **pages,
{
int i;
LIST_HEAD(pages_to_free);
- struct pglist_data *locked_pgdat = NULL;
- struct lruvec *lruvec;
+ struct lruvec *lruvec = NULL;
unsigned long flags;
unsigned int lock_batch;
@@ -871,11 +874,11 @@ void release_pages(struct page **pages,
/*
* 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;
}
page = compound_head(page);
@@ -883,10 +886,9 @@ void release_pages(struct page **pages,
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
@@ -907,27 +909,27 @@ void release_pages(struct page **pages,
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;
- if (pgdat != locked_pgdat) {
- if (locked_pgdat)
- spin_unlock_irqrestore(&locked_pgdat->lru_lock,
+ new_lruvec = mem_cgroup_page_lruvec(page,
+ page_pgdat(page));
+ 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));
@@ -937,8 +939,8 @@ void release_pages(struct page **pages,
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);
@@ -1026,26 +1028,24 @@ static void __pagevec_lru_add_fn(struct
void __pagevec_lru_add(struct pagevec *pvec)
{
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);
+ struct lruvec *new_lruvec;
- if (pagepgdat != pgdat) {
- if (pgdat)
- spin_unlock_irqrestore(&pgdat->lru_lock, flags);
- pgdat = pagepgdat;
- spin_lock_irqsave(&pgdat->lru_lock, flags);
+ new_lruvec = mem_cgroup_page_lruvec(page, page_pgdat(page));
+ if (lruvec != new_lruvec) {
+ if (lruvec)
+ unlock_page_lruvec_irqrestore(lruvec, flags);
+ lruvec = lock_page_lruvec_irqsave(page, &flags);
}
- lruvec = mem_cgroup_page_lruvec(page, pgdat);
__pagevec_lru_add_fn(page, lruvec);
}
- if (pgdat)
- spin_unlock_irqrestore(&pgdat->lru_lock, flags);
+ if (lruvec)
+ unlock_page_lruvec_irqrestore(lruvec, flags);
release_pages(pvec->pages, pvec->nr);
pagevec_reinit(pvec);
}
--- a/mm/vmscan.c~mm-lru-replace-pgdat-lru_lock-with-lruvec-lock
+++ a/mm/vmscan.c
@@ -1765,14 +1765,12 @@ int isolate_lru_page(struct page *page)
WARN_RATELIMIT(PageTail(page), "trying to isolate tail page");
if (TestClearPageLRU(page)) {
- pg_data_t *pgdat = page_pgdat(page);
struct lruvec *lruvec;
get_page(page);
- lruvec = mem_cgroup_page_lruvec(page, pgdat);
- spin_lock_irq(&pgdat->lru_lock);
+ lruvec = lock_page_lruvec_irq(page);
del_page_from_lru_list(page, lruvec, page_lru(page));
- spin_unlock_irq(&pgdat->lru_lock);
+ unlock_page_lruvec_irq(lruvec);
ret = 0;
}
@@ -1839,7 +1837,6 @@ static int too_many_isolated(struct pgli
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;
@@ -1850,9 +1847,9 @@ static unsigned noinline_for_stack move_
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;
}
@@ -1874,9 +1871,9 @@ static unsigned noinline_for_stack move_
__ClearPageActive(page);
if (unlikely(PageCompound(page))) {
- spin_unlock_irq(&pgdat->lru_lock);
+ spin_unlock_irq(&lruvec->lru_lock);
destroy_compound_page(page);
- spin_lock_irq(&pgdat->lru_lock);
+ spin_lock_irq(&lruvec->lru_lock);
} else
list_add(&page->lru, &pages_to_free);
@@ -1953,7 +1950,7 @@ shrink_inactive_list(unsigned long nr_to
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);
@@ -1965,14 +1962,14 @@ shrink_inactive_list(unsigned long nr_to
__count_memcg_events(lruvec_memcg(lruvec), item, nr_scanned);
__count_vm_events(PGSCAN_ANON + file, 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, &stat, false);
- spin_lock_irq(&pgdat->lru_lock);
+ spin_lock_irq(&lruvec->lru_lock);
move_pages_to_lru(lruvec, &page_list);
__mod_node_page_state(pgdat, NR_ISOLATED_ANON + file, -nr_taken);
@@ -1981,7 +1978,7 @@ shrink_inactive_list(unsigned long nr_to
__count_vm_events(item, nr_reclaimed);
__count_memcg_events(lruvec_memcg(lruvec), item, nr_reclaimed);
__count_vm_events(PGSTEAL_ANON + file, nr_reclaimed);
- spin_unlock_irq(&pgdat->lru_lock);
+ spin_unlock_irq(&lruvec->lru_lock);
lru_note_cost(lruvec, file, stat.nr_pageout);
mem_cgroup_uncharge_list(&page_list);
@@ -2034,7 +2031,7 @@ static void shrink_active_list(unsigned
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);
@@ -2045,7 +2042,7 @@ static void shrink_active_list(unsigned
__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();
@@ -2091,7 +2088,7 @@ static void shrink_active_list(unsigned
/*
* Move pages back to the lru list.
*/
- spin_lock_irq(&pgdat->lru_lock);
+ spin_lock_irq(&lruvec->lru_lock);
nr_activate = move_pages_to_lru(lruvec, &l_active);
nr_deactivate = move_pages_to_lru(lruvec, &l_inactive);
@@ -2102,7 +2099,7 @@ static void shrink_active_list(unsigned
__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);
@@ -2690,10 +2687,10 @@ again:
/*
* Determine the scan balance between anon and file LRUs.
*/
- spin_lock_irq(&pgdat->lru_lock);
+ spin_lock_irq(&target_lruvec->lru_lock);
sc->anon_cost = target_lruvec->anon_cost;
sc->file_cost = target_lruvec->file_cost;
- spin_unlock_irq(&pgdat->lru_lock);
+ spin_unlock_irq(&target_lruvec->lru_lock);
/*
* Target desirable inactive:active list ratios for the anon
@@ -4269,16 +4266,15 @@ int node_reclaim(struct pglist_data *pgd
*/
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);
int nr_pages;
+ struct lruvec *new_lruvec;
if (PageTransTail(page))
continue;
@@ -4290,13 +4286,12 @@ void check_move_unevictable_pages(struct
if (!TestClearPageLRU(page))
continue;
- if (pagepgdat != pgdat) {
- if (pgdat)
- spin_unlock_irq(&pgdat->lru_lock);
- pgdat = pagepgdat;
- spin_lock_irq(&pgdat->lru_lock);
+ new_lruvec = mem_cgroup_page_lruvec(page, page_pgdat(page));
+ 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 (page_evictable(page) && PageUnevictable(page)) {
enum lru_list lru = page_lru_base_type(page);
@@ -4310,10 +4305,10 @@ void check_move_unevictable_pages(struct
SetPageLRU(page);
}
- 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);
} else if (pgscanned) {
count_vm_events(UNEVICTABLE_PGSCANNED, pgscanned);
}
_
Patches currently in -mm which might be from alex.shi@linux.alibaba.com are
mm-filemap-add-static-for-function-__add_to_page_cache_locked.patch
fs-ntfs-remove-unused-varibles.patch
fs-ntfs-remove-unused-varible-attr_len.patch
mm-memcg-update-page-struct-member-in-comments.patch
mm-thp-move-lru_add_page_tail-func-to-huge_memoryc.patch
mm-thp-use-head-for-head-page-in-lru_add_page_tail.patch
mm-thp-simplify-lru_add_page_tail.patch
mm-thp-narrow-lru-locking.patch
mm-vmscan-remove-unnecessary-lruvec-adding.patch
mm-rmap-stop-store-reordering-issue-on-page-mapping.patch
mm-rmap-stop-store-reordering-issue-on-page-mapping-fix.patch
mm-memcg-add-debug-checking-in-lock_page_memcg.patch
mm-swapc-fold-vm-event-pgrotated-into-pagevec_move_tail_fn.patch
mm-lru-move-lock-into-lru_note_cost.patch
mm-vmscan-remove-lruvec-reget-in-move_pages_to_lru.patch
mm-mlock-remove-lru_lock-on-testclearpagemlocked.patch
mm-mlock-remove-__munlock_isolate_lru_page.patch
mm-lru-introduce-testclearpagelru.patch
mm-compaction-do-page-isolation-first-in-compaction.patch
mm-swapc-serialize-memcg-changes-in-pagevec_lru_move_fn.patch
mm-lru-replace-pgdat-lru_lock-with-lruvec-lock.patch
mm-lru-replace-pgdat-lru_lock-with-lruvec-lock-fix.patch
mm-lru-replace-pgdat-lru_lock-with-lruvec-lock-fix-2.patch
mm-lru-introduce-the-relock_page_lruvec-function-fix.patch
docs-vm-remove-unused-3-items-explanation-for-proc-vmstat.patch
mm-memcg-bail-early-from-swap-accounting-if-memcg-disabled.patch
mm-memcg-warning-on-memcg-after-readahead-page-charged.patch
^ permalink raw reply [flat|nested] 2+ messages in thread
* Re: + mm-lru-replace-pgdat-lru_lock-with-lruvec-lock.patch added to -mm tree
2020-11-16 21:57 + mm-lru-replace-pgdat-lru_lock-with-lruvec-lock.patch added to -mm tree akpm
@ 2020-11-19 6:26 ` Alex Shi
0 siblings, 0 replies; 2+ messages in thread
From: Alex Shi @ 2020-11-19 6:26 UTC (permalink / raw)
To: akpm, aarcange, alexander.duyck, aryabinin, daniel.m.jordan,
hannes, hughd, iamjoonsoo.kim, jannh, khlebnikov,
kirill.shutemov, kirill, mgorman, mhocko, mhocko, mika.penttila,
minchan, mm-commits, richard.weiyang, rong.a.chen, shakeelb,
tglx, tj, vbabka, vdavydov.dev, willy, yang.shi, ying.huang
在 2020/11/17 上午5:57, akpm@linux-foundation.org 写道:
> On a large machine with memcg enabled but not used, the page's lruvec
> seeking pass a few pointers, that may lead to lru_lock holding time
> increase and a bit regression.
Hi Andrew,
Few pointer walking actually has no clear impact in above mentioned
situation, so could you please remove above section? when you merge the
3 'replace lru pgdat lru_lock' patches linux-next/akpm or master branch.
3d0d6a8434e1 mm-lru-replace-pgdat-lru_lock-with-lruvec-lock-fix-2
6bffb6674742 mm-lru-replace-pgdat-lru_lock-with-lruvec-lock-fix
7c3520054e02 mm/lru: replace pgdat lru_lock with lruvec lock
Also thanks a lot for couple commit log polish on whole series!
Thanks again!
Alex
^ permalink raw reply [flat|nested] 2+ messages in thread
end of thread, other threads:[~2020-11-19 6:28 UTC | newest]
Thread overview: 2+ messages (download: mbox.gz / follow: Atom feed)
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2020-11-16 21:57 + mm-lru-replace-pgdat-lru_lock-with-lruvec-lock.patch added to -mm tree akpm
2020-11-19 6:26 ` Alex Shi
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