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Sat, 1 Aug 2020 01:20:51 +0000 Date: Fri, 31 Jul 2020 18:20:48 -0700 From: Roman Gushchin To: Hugh Dickins CC: Andrew Morton , Johannes Weiner , Shakeel Butt , , Subject: Re: [PATCH mmotm] mm: memcontrol: decouple reference counting from page accounting fix Message-ID: <20200801012048.GA860216@carbon.dhcp.thefacebook.com> References: Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: X-ClientProxiedBy: BYAPR08CA0072.namprd08.prod.outlook.com (2603:10b6:a03:117::49) To BYAPR15MB4136.namprd15.prod.outlook.com (2603:10b6:a03:96::24) MIME-Version: 1.0 X-MS-Exchange-MessageSentRepresentingType: 1 Received: from carbon.dhcp.thefacebook.com (2620:10d:c090:400::5:562c) by BYAPR08CA0072.namprd08.prod.outlook.com (2603:10b6:a03:117::49) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.20.3239.18 via Frontend Transport; Sat, 1 Aug 2020 01:20:50 +0000 X-Originating-IP: [2620:10d:c090:400::5:562c] X-MS-PublicTrafficType: Email X-MS-Office365-Filtering-Correlation-Id: 63d79efb-a7b5-4b07-0e4e-08d835b920f8 X-MS-TrafficTypeDiagnostic: BYAPR15MB3128: X-Microsoft-Antispam-PRVS: X-FB-Source: Internal X-MS-Oob-TLC-OOBClassifiers: OLM:10000; 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and stats > temporarily hacked into mem_cgroup_css_alloc() and mem_cgroup_css_free() > showed that mem cgroups were not being leaked with this change. > > Note: this removes the last call to css_put_many() from the tree; and > mm-memcg-slab-use-a-single-set-of-kmem_caches-for-all-accounted-allocations.patch > removes the last call to css_get_many(): now that their last references > have gone, I expect them soon to be freed from include/linux/cgroup.h. > > Signed-off-by: Hugh Dickins > --- > Fixes mm-memcontrol-decouple-reference-counting-from-page-accounting.patch > > mm/memcontrol.c | 2 -- > 1 file changed, 2 deletions(-) > > --- mmotm/mm/memcontrol.c 2020-07-27 18:55:00.700554752 -0700 > +++ linux/mm/memcontrol.c 2020-07-30 12:05:00.640091618 -0700 > @@ -5887,8 +5887,6 @@ static void __mem_cgroup_clear_mc(void) > if (!mem_cgroup_is_root(mc.to)) > page_counter_uncharge(&mc.to->memory, mc.moved_swap); > > - css_put_many(&mc.to->css, mc.moved_swap); > - > mc.moved_swap = 0; > } > memcg_oom_recover(from); Acked-by: Roman Gushchin Good catch! Thank you, Hugh!