[PATCH v12 13/16] mm/lru: introduce the relock_page_lruvec function

Alex Shi
2020-06-11T06:16:46Z

Use this new function to replace repeated same code.

Signed-off-by: Alex Shi <alex.shi@linux.alibaba.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Andrey Ryabinin <aryabinin@virtuozzo.com>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Mel Gorman <mgorman@techsingularity.net>
Cc: Konstantin Khlebnikov <khlebnikov@yandex-team.ru>
Cc: Hugh Dickins <hughd@google.com>
Cc: Tejun Heo <tj@kernel.org>
Cc: linux-kernel@vger.kernel.org
Cc: cgroups@vger.kernel.org
Cc: linux-mm@kvack.org
---
include/linux/memcontrol.h | 36 ++++++++++++++++++++++++++++++++++++
mm/mlock.c | 9 +--------
mm/swap.c | 24 ++++++------------------
mm/vmscan.c | 8 +-------
4 files changed, 44 insertions(+), 33 deletions(-)

diff --git a/include/linux/memcontrol.h b/include/linux/memcontrol.h
index 6b821b0c8852..d90643246c77 100644
--- a/include/linux/memcontrol.h
+++ b/include/linux/memcontrol.h
@@ -1311,6 +1311,42 @@ static inline struct lruvec *parent_lruvec(struct lruvec *lruvec)
return mem_cgroup_lruvec(memcg, lruvec_pgdat(lruvec));
}

+/* Don't lock again iff page's lruvec locked */
+static inline struct lruvec *relock_page_lruvec_irq(struct page *page,
+ struct lruvec *locked_lruvec)
+{
+ struct pglist_data *pgdat = page_pgdat(page);
+ struct lruvec *lruvec;
+
+ lruvec = mem_cgroup_page_lruvec(page, pgdat);
+
+ if (likely(locked_lruvec == lruvec))
+ return lruvec;
+
+ if (unlikely(locked_lruvec))
+ unlock_page_lruvec_irq(locked_lruvec);
+
+ return lock_page_lruvec_irq(page);
+}
+
+/* Don't lock again iff page's lruvec locked */
+static inline struct lruvec *relock_page_lruvec_irqsave(struct page *page,
+ struct lruvec *locked_lruvec, unsigned long *flags)
+{
+ struct pglist_data *pgdat = page_pgdat(page);
+ struct lruvec *lruvec;
+
+ lruvec = mem_cgroup_page_lruvec(page, pgdat);
+
+ if (likely(locked_lruvec == lruvec))
+ return lruvec;
+
+ if (unlikely(locked_lruvec))
+ unlock_page_lruvec_irqrestore(locked_lruvec, *flags);
+
+ return lock_page_lruvec_irqsave(page, flags);
+}
+
#ifdef CONFIG_CGROUP_WRITEBACK

struct wb_domain *mem_cgroup_wb_domain(struct bdi_writeback *wb);
diff --git a/mm/mlock.c b/mm/mlock.c
index 97a8667b4c2c..fa976a5b91c7 100644
--- a/mm/mlock.c
+++ b/mm/mlock.c
@@ -289,17 +289,10 @@ static void __munlock_pagevec(struct pagevec *pvec, struct zone *zone)
/* Phase 1: page isolation */
for (i = 0; i < nr; i++) {
struct page *page = pvec->pages[i];
- struct lruvec *new_lruvec;
bool clearlru;

clearlru = TestClearPageLRU(page);
-
- 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 = relock_page_lruvec_irq(page, lruvec);

if (!TestClearPageMlocked(page)) {
delta_munlocked++;
diff --git a/mm/swap.c b/mm/swap.c
index c9b86d7e1ab5..eba0c17dffd8 100644
--- a/mm/swap.c
+++ b/mm/swap.c
@@ -209,15 +209,8 @@ static void pagevec_lru_move_fn(struct pagevec *pvec,

for (i = 0; i < pagevec_count(pvec); i++) {
struct page *page = pvec->pages[i];
- struct lruvec *new_lruvec;
-
- 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 = relock_page_lruvec_irqsave(page, lruvec, &flags);
(*move_fn)(page, lruvec, arg);
}
if (lruvec)
@@ -875,17 +868,12 @@ void release_pages(struct page **pages, int nr)
}

if (TestClearPageLRU(page)) {
- struct lruvec *new_lruvec;
-
- new_lruvec = mem_cgroup_page_lruvec(page,
- page_pgdat(page));
- if (new_lruvec != lruvec) {
- if (lruvec)
- unlock_page_lruvec_irqrestore(lruvec,
- flags);
+ struct lruvec *pre_lruvec = lruvec;
+
+ lruvec = relock_page_lruvec_irqsave(page, lruvec,
+ &flags);
+ if (pre_lruvec != lruvec)
lock_batch = 0;
- lruvec = lock_page_lruvec_irqsave(page, &flags);
- }

del_page_from_lru_list(page, lruvec, page_off_lru(page));
}
diff --git a/mm/vmscan.c b/mm/vmscan.c
index 4d5a0b660c82..1253cdb16c96 100644
--- a/mm/vmscan.c
+++ b/mm/vmscan.c
@@ -4291,15 +4291,9 @@ void check_move_unevictable_pages(struct pagevec *pvec)

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

pgscanned++;
- 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 = relock_page_lruvec_irq(page, lruvec);

if (!PageLRU(page) || !PageUnevictable(page))
continue;
--
1.8.3.1