lkml.org 
[lkml]   [2022]   [Mar]   [28]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
Date
From
SubjectRe: [PATCH] mm/memcg: remove unneeded nr_scanned
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@huawei.com>

Acked-by: Michal Hocko <mhocko@suse.com>

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

\
 
 \ /
  Last update: 2022-03-28 14:02    [W:0.387 / U:0.076 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site