From d60b7e927d820375dc4e112802fc74cadd499a40 Mon Sep 17 00:00:00 2001 From: Chen Ridong Date: Fri, 24 Jan 2025 07:35:13 +0000 Subject: [PATCH] memcg: factor out the replace_stock_objcg function MIME-Version: 1.0 Content-Type: text/plain; charset=utf8 Content-Transfer-Encoding: 8bit Factor out the 'replace_stock_objcg' function to make the code more cohesive. Link: https://lkml.kernel.org/r/20250124073514.2375622-4-chenridong@huaweicloud.com Signed-off-by: Chen Ridong Reviewed-by: Roman Gushchin Acked-by: Shakeel Butt Acked-by: Johannes Weiner Cc: David Finkel Cc: Michal Hocko Cc: Michal Hocko Cc: Michal Koutný Cc: Muchun Song Cc: Muchun Song Cc: Vlastimil Babka Cc: Wang Weiyang Cc: Yosry Ahmed Signed-off-by: Andrew Morton --- mm/memcontrol.c | 26 ++++++++++++++++---------- 1 file changed, 16 insertions(+), 10 deletions(-) diff --git a/mm/memcontrol.c b/mm/memcontrol.c index 1ece6c0ede9b..8239d3a79784 100644 --- a/mm/memcontrol.c +++ b/mm/memcontrol.c @@ -2691,6 +2691,20 @@ void __memcg_kmem_uncharge_page(struct page *page, int order) obj_cgroup_put(objcg); } +/* Replace the stock objcg with objcg, return the old objcg */ +static struct obj_cgroup *replace_stock_objcg(struct memcg_stock_pcp *stock, + struct obj_cgroup *objcg) +{ + struct obj_cgroup *old = NULL; + + old = drain_obj_stock(stock); + obj_cgroup_get(objcg); + stock->nr_bytes = atomic_read(&objcg->nr_charged_bytes) + ? atomic_xchg(&objcg->nr_charged_bytes, 0) : 0; + WRITE_ONCE(stock->cached_objcg, objcg); + return old; +} + static void mod_objcg_state(struct obj_cgroup *objcg, struct pglist_data *pgdat, enum node_stat_item idx, int nr) { @@ -2708,11 +2722,7 @@ static void mod_objcg_state(struct obj_cgroup *objcg, struct pglist_data *pgdat, * changes. */ if (READ_ONCE(stock->cached_objcg) != objcg) { - old = drain_obj_stock(stock); - obj_cgroup_get(objcg); - stock->nr_bytes = atomic_read(&objcg->nr_charged_bytes) - ? atomic_xchg(&objcg->nr_charged_bytes, 0) : 0; - WRITE_ONCE(stock->cached_objcg, objcg); + old = replace_stock_objcg(stock, objcg); stock->cached_pgdat = pgdat; } else if (stock->cached_pgdat != pgdat) { /* Flush the existing cached vmstat data */ @@ -2866,11 +2876,7 @@ static void refill_obj_stock(struct obj_cgroup *objcg, unsigned int nr_bytes, stock = this_cpu_ptr(&memcg_stock); if (READ_ONCE(stock->cached_objcg) != objcg) { /* reset if necessary */ - old = drain_obj_stock(stock); - obj_cgroup_get(objcg); - WRITE_ONCE(stock->cached_objcg, objcg); - stock->nr_bytes = atomic_read(&objcg->nr_charged_bytes) - ? atomic_xchg(&objcg->nr_charged_bytes, 0) : 0; + old = replace_stock_objcg(stock, objcg); allow_uncharge = true; /* Allow uncharge when objcg changes */ } stock->nr_bytes += nr_bytes; -- 2.50.1