[PATCH v17 12/21] mm/lru: move lock into lru_note_cost

Alex Shi
2020-07-25T12:59:49Z

This patch move lru_lock into lru_note_cost. It's a bit ugly and may
cost more locking, but it's necessary for later per pgdat lru_lock to
per memcg lru_lock change.

Signed-off-by: Alex Shi <alex.shi-KPsoFbNs7GizrGE5bRqYAgC/G2K4zDHf@public.gmane.org>
Cc: Johannes Weiner <hannes-druUgvl0LCNAfugRpC6u6w@public.gmane.org>
Cc: Andrew Morton <akpm-de/tnXTf+JLsfHDXvbKv3WD2FQJk+8+b@public.gmane.org>
Cc: linux-mm-Bw31MaZKKs3YtjvyW6yDsg@public.gmane.org
Cc: linux-kernel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org
---
mm/swap.c | 5 +++--
mm/vmscan.c | 4 +---
2 files changed, 4 insertions(+), 5 deletions(-)

diff --git a/mm/swap.c b/mm/swap.c
index b88ca630db70..f645965fde0e 100644
--- a/mm/swap.c
+++ b/mm/swap.c
@@ -269,7 +269,9 @@ void lru_note_cost(struct lruvec *lruvec, bool file, unsigned int nr_pages)
{
do {
unsigned long lrusize;
+ struct pglist_data *pgdat = lruvec_pgdat(lruvec);

+ spin_lock_irq(&pgdat->lru_lock);
/* Record cost event */
if (file)
lruvec->file_cost += nr_pages;
@@ -293,15 +295,14 @@ void lru_note_cost(struct lruvec *lruvec, bool file, unsigned int nr_pages)
lruvec->file_cost /= 2;
lruvec->anon_cost /= 2;
}
+ spin_unlock_irq(&pgdat->lru_lock);
} while ((lruvec = parent_lruvec(lruvec)));
}

void lru_note_cost_page(struct page *page)
{
- spin_lock_irq(&page_pgdat(page)->lru_lock);
lru_note_cost(mem_cgroup_page_lruvec(page, page_pgdat(page)),
page_is_file_lru(page), hpage_nr_pages(page));
- spin_unlock_irq(&page_pgdat(page)->lru_lock);
}

static void __activate_page(struct page *page, struct lruvec *lruvec)
diff --git a/mm/vmscan.c b/mm/vmscan.c
index ddb29d813d77..c1c4259b4de5 100644
--- a/mm/vmscan.c
+++ b/mm/vmscan.c
@@ -1976,19 +1976,17 @@ static int current_may_throttle(void)
&stat, false);

spin_lock_irq(&pgdat->lru_lock);
-
move_pages_to_lru(lruvec, &page_list);

__mod_node_page_state(pgdat, NR_ISOLATED_ANON + file, -nr_taken);
- lru_note_cost(lruvec, file, stat.nr_pageout);
item = current_is_kswapd() ? PGSTEAL_KSWAPD : PGSTEAL_DIRECT;
if (!cgroup_reclaim(sc))
__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);

+ lru_note_cost(lruvec, file, stat.nr_pageout);
mem_cgroup_uncharge_list(&page_list);
free_unref_page_list(&page_list);

--
1.8.3.1