lkml.org 
[lkml]   [2014]   [Feb]   [10]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
Date
From
SubjectRe: [patch 1/8] mm: memcg: remove unnecessary preemption disabling
On Fri 07-02-14 12:04:18, Johannes Weiner wrote:
> lock_page_cgroup() disables preemption, remove explicit preemption
> disabling for code paths holding this lock.
>
> Signed-off-by: Johannes Weiner <hannes@cmpxchg.org>

It would be better to document the dependency on lock_page_cgroup. But
the patch looks correct.

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

> ---
> mm/memcontrol.c | 15 ++++-----------
> 1 file changed, 4 insertions(+), 11 deletions(-)
>
> diff --git a/mm/memcontrol.c b/mm/memcontrol.c
> index 53385cd4e6f0..befb3dd9d46c 100644
> --- a/mm/memcontrol.c
> +++ b/mm/memcontrol.c
> @@ -921,8 +921,6 @@ static void mem_cgroup_charge_statistics(struct mem_cgroup *memcg,
> struct page *page,
> bool anon, int nr_pages)
> {
> - preempt_disable();
> -
> /*
> * Here, RSS means 'mapped anon' and anon's SwapCache. Shmem/tmpfs is
> * counted as CACHE even if it's on ANON LRU.
> @@ -947,8 +945,6 @@ static void mem_cgroup_charge_statistics(struct mem_cgroup *memcg,
> }
>
> __this_cpu_add(memcg->stat->nr_page_events, nr_pages);
> -
> - preempt_enable();
> }
>
> unsigned long
> @@ -3780,17 +3776,14 @@ void mem_cgroup_split_huge_fixup(struct page *head)
> }
> #endif /* CONFIG_TRANSPARENT_HUGEPAGE */
>
> -static inline
> -void mem_cgroup_move_account_page_stat(struct mem_cgroup *from,
> - struct mem_cgroup *to,
> - unsigned int nr_pages,
> - enum mem_cgroup_stat_index idx)
> +static void mem_cgroup_move_account_page_stat(struct mem_cgroup *from,
> + struct mem_cgroup *to,
> + unsigned int nr_pages,
> + enum mem_cgroup_stat_index idx)
> {
> /* Update stat data for mem_cgroup */
> - preempt_disable();
> __this_cpu_sub(from->stat->count[idx], nr_pages);
> __this_cpu_add(to->stat->count[idx], nr_pages);
> - preempt_enable();
> }
>
> /**
> --
> 1.8.5.3
>

--
Michal Hocko
SUSE Labs


\
 
 \ /
  Last update: 2014-02-10 15:41    [W:0.121 / U:0.176 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site