On Mon 28-03-22 19:41:44, Miaohe Lin wrote: > 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. Maybe the compiler could be clever enough to generate a good code. mem_cgroup_soft_reclaim doesn't have other caller so it could be inlined. But I do agree that the change makes sense because it makes the code more consistent as mem_cgroup_soft_limit_reclaim already uses total_scanned this way. > Signed-off-by: Miaohe Lin <linmiaohe@xxxxxxxxxx> Acked-by: Michal Hocko <mhocko@xxxxxxxx> Thanks > --- > mm/memcontrol.c | 5 +---- > 1 file changed, 1 insertion(+), 4 deletions(-) > > diff --git a/mm/memcontrol.c b/mm/memcontrol.c > index b686ec4f42c6..79341365ec90 100644 > --- a/mm/memcontrol.c > +++ b/mm/memcontrol.c > @@ -3384,7 +3384,6 @@ 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; > @@ -3412,11 +3411,9 @@ 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); > > -- > 2.23.0 -- Michal Hocko SUSE Labs