From: Michal Hocko <mhocko@suse.com>
To: Tim Chen <tim.c.chen@linux.intel.com>
Cc: Andrew Morton <akpm@linux-foundation.org>,
Johannes Weiner <hannes@cmpxchg.org>,
Vladimir Davydov <vdavydov.dev@gmail.com>,
Dave Hansen <dave.hansen@intel.com>,
Ying Huang <ying.huang@intel.com>,
linux-mm@kvack.org, cgroups@vger.kernel.org,
linux-kernel@vger.kernel.org
Subject: Re: [PATCH v2 1/3] mm: Fix dropped memcg from mem cgroup soft limit tree
Date: Thu, 18 Feb 2021 20:13:34 +0100 [thread overview]
Message-ID: <YC68Xo9+R2msn/ul@dhcp22.suse.cz> (raw)
In-Reply-To: <8d35206601ccf0e1fe021d24405b2a0c2f4e052f.1613584277.git.tim.c.chen@linux.intel.com>
On Wed 17-02-21 12:41:34, Tim Chen wrote:
> During soft limit memory reclaim, we will temporarily remove the target
> mem cgroup from the cgroup soft limit tree. We then perform memory
> reclaim, update the memory usage excess count and re-insert the mem
> cgroup back into the mem cgroup soft limit tree according to the new
> memory usage excess count.
>
> However, when memory reclaim failed for a maximum number of attempts
> and we bail out of the reclaim loop, we forgot to put the target mem
> cgroup chosen for next reclaim back to the soft limit tree. This prevented
> pages in the mem cgroup from being reclaimed in the future even though
> the mem cgroup exceeded its soft limit. Fix the logic and put the mem
> cgroup back on the tree when page reclaim failed for the mem cgroup.
>
> Reviewed-by: Ying Huang <ying.huang@intel.com>
> Signed-off-by: Tim Chen <tim.c.chen@linux.intel.com>
Fixes: 4e41695356fb ("memory controller: soft limit reclaim on contention")
Acked-by: Michal Hocko <mhocko@suse.com>
Thanks!
> ---
> mm/memcontrol.c | 6 +++++-
> 1 file changed, 5 insertions(+), 1 deletion(-)
>
> diff --git a/mm/memcontrol.c b/mm/memcontrol.c
> index ed5cc78a8dbf..a51bf90732cb 100644
> --- a/mm/memcontrol.c
> +++ b/mm/memcontrol.c
> @@ -3505,8 +3505,12 @@ unsigned long mem_cgroup_soft_limit_reclaim(pg_data_t *pgdat, int order,
> loop > MEM_CGROUP_MAX_SOFT_LIMIT_RECLAIM_LOOPS))
> break;
> } while (!nr_reclaimed);
> - if (next_mz)
> + if (next_mz) {
> + spin_lock_irq(&mctz->lock);
> + __mem_cgroup_insert_exceeded(next_mz, mctz, excess);
> + spin_unlock_irq(&mctz->lock);
> css_put(&next_mz->memcg->css);
> + }
> return nr_reclaimed;
> }
>
> --
> 2.20.1
--
Michal Hocko
SUSE Labs
next prev parent reply other threads:[~2021-02-18 19:46 UTC|newest]
Thread overview: 35+ messages / expand[flat|nested] mbox.gz Atom feed top
2021-02-17 20:41 [PATCH v2 0/3] Soft limit memory management bug fixes Tim Chen
2021-02-17 20:41 ` [PATCH v2 1/3] mm: Fix dropped memcg from mem cgroup soft limit tree Tim Chen
2021-02-18 8:24 ` Michal Hocko
2021-02-18 18:30 ` Tim Chen
2021-02-18 19:13 ` Michal Hocko
2021-02-18 19:51 ` Tim Chen
2021-02-18 19:13 ` Michal Hocko [this message]
2021-03-04 17:35 ` Tim Chen
2021-03-05 9:11 ` Michal Hocko
2021-03-05 19:07 ` Tim Chen
2021-03-08 8:34 ` Michal Hocko
2021-02-17 20:41 ` [PATCH v2 2/3] mm: Force update of mem cgroup soft limit tree on usage excess Tim Chen
2021-02-19 9:11 ` Michal Hocko
2021-02-19 18:59 ` Tim Chen
2021-02-20 16:23 ` Tim Chen
2021-02-22 8:40 ` Michal Hocko
2021-02-22 17:41 ` Tim Chen
2021-02-22 19:09 ` Michal Hocko
2021-02-22 19:23 ` Tim Chen
2021-02-22 19:48 ` Tim Chen
2021-02-24 11:53 ` Michal Hocko
2021-02-25 22:48 ` Tim Chen
2021-02-26 8:52 ` Michal Hocko
2021-02-27 0:56 ` Tim Chen
2021-03-01 7:39 ` Michal Hocko
2021-02-25 22:25 ` Tim Chen
2021-03-02 6:25 ` [mm] 4f09feb8bf: vm-scalability.throughput -4.3% regression kernel test robot
2021-02-17 20:41 ` [PATCH v2 3/3] mm: Fix missing mem cgroup soft limit tree updates Tim Chen
2021-02-18 5:56 ` Johannes Weiner
2021-02-22 18:38 ` Tim Chen
2021-02-23 15:18 ` Johannes Weiner
2021-02-19 9:16 ` Michal Hocko
2021-02-19 19:28 ` Tim Chen
2021-02-22 8:41 ` Michal Hocko
2021-02-22 17:45 ` Tim Chen
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=YC68Xo9+R2msn/ul@dhcp22.suse.cz \
--to=mhocko@suse.com \
--cc=akpm@linux-foundation.org \
--cc=cgroups@vger.kernel.org \
--cc=dave.hansen@intel.com \
--cc=hannes@cmpxchg.org \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-mm@kvack.org \
--cc=tim.c.chen@linux.intel.com \
--cc=vdavydov.dev@gmail.com \
--cc=ying.huang@intel.com \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).