mm/memcg: remove unneeded nr_scanned

The local variable nr_scanned is unneeded as mem_cgroup_soft_reclaim
always does *total_scanned += nr_scanned.  So we can pass total_scanned
directly to the mem_cgroup_soft_reclaim to simplify the code and save some
cpu cycles of adding nr_scanned to total_scanned.

Link: https://lkml.kernel.org/r/20220328114144.53389-1-linmiaohe@huawei.com
Signed-off-by: Miaohe Lin <linmiaohe@huawei.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Reviewed-by: David Hildenbrand <david@redhat.com>
Reviewed-by: Roman Gushchin <roman.gushchin@linux.dev>
Reviewed-by: Wei Yang <richard.weiyang@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

diff --git a/mm/memcontrol.c b/mm/memcontrol.c
index 598fece..09df048 100644 (file)
--- a/mm/memcontrol.c
+++ b/mm/memcontrol.c
@@ -3387,7 +3387,6 @@ unsigned long mem_cgroup_soft_limit_reclaim(pg_data_t *pgdat, int order,
        int loop = 0;
        struct mem_cgroup_tree_per_node *mctz;
        unsigned long excess;
-       unsigned long nr_scanned;
 
        if (order > 0)
                return 0;
@@ -3415,11 +3414,9 @@ unsigned long mem_cgroup_soft_limit_reclaim(pg_data_t *pgdat, int order,
                if (!mz)
                        break;
 
-               nr_scanned = 0;
                reclaimed = mem_cgroup_soft_reclaim(mz->memcg, pgdat,
-                                                   gfp_mask, &nr_scanned);
+                                                   gfp_mask, total_scanned);
                nr_reclaimed += reclaimed;
-               *total_scanned += nr_scanned;
                spin_lock_irq(&mctz->lock);
                __mem_cgroup_remove_exceeded(mz, mctz);