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From: Roman Gushchin <roman.gushchin@linux.dev>
To: Shakeel Butt <shakeel.butt@linux.dev>
Cc: Andrew Morton <akpm@linux-foundation.org>,
	Johannes Weiner <hannes@cmpxchg.org>,
	Michal Hocko <mhocko@kernel.org>,
	Muchun Song <muchun.song@linux.dev>, linux-mm@kvack.org,
	cgroups@vger.kernel.org, linux-kernel@vger.kernel.org,
	Meta kernel team <kernel-team@meta.com>, stable@vger.kernel.org
Subject: Re: [PATCH] memcg: drain obj stock on cpu hotplug teardown
Message-ID: <Z9BkOgZIK1iSQKd5@google.com>
References: <20250310230934.2913113-1-shakeel.butt@linux.dev>
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On Mon, Mar 10, 2025 at 04:09:34PM -0700, Shakeel Butt wrote:
> Currently on cpu hotplug teardown, only memcg stock is drained but we
> need to drain the obj stock as well otherwise we will miss the stats
> accumulated on the target cpu as well as the nr_bytes cached. The stats
> include MEMCG_KMEM, NR_SLAB_RECLAIMABLE_B & NR_SLAB_UNRECLAIMABLE_B. In
> addition we are leaking reference to struct obj_cgroup object.
> 
> Fixes: bf4f059954dc ("mm: memcg/slab: obj_cgroup API")
> Signed-off-by: Shakeel Butt <shakeel.butt@linux.dev>
> Cc: <stable@vger.kernel.org>

Reviewed-by: Roman Gushchin <roman.gushchin@linux.dev>

Thanks!