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Wed, 30 Sep 2020 23:44:49 +0000 Date: Wed, 30 Sep 2020 16:44:45 -0700 From: Roman Gushchin To: Shakeel Butt CC: Andrew Morton , Johannes Weiner , Michal Hocko , LKML , Linux MM , Kernel Team Subject: Re: [PATCH v3 3/4] mm: introduce page memcg flags Message-ID: <20200930234445.GA2700710@carbon.dhcp.thefacebook.com> References: <20200929235920.537849-1-guro@fb.com> <20200929235920.537849-4-guro@fb.com> Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: X-Originating-IP: [2620:10d:c090:400::5:59ab] X-ClientProxiedBy: MWHPR1701CA0013.namprd17.prod.outlook.com (2603:10b6:301:14::23) To SN6PR1501MB4141.namprd15.prod.outlook.com (2603:10b6:805:e3::14) MIME-Version: 1.0 X-MS-Exchange-MessageSentRepresentingType: 1 Received: from carbon.dhcp.thefacebook.com (2620:10d:c090:400::5:59ab) by MWHPR1701CA0013.namprd17.prod.outlook.com (2603:10b6:301:14::23) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.20.3412.20 via Frontend Transport; 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> > > > +enum page_memcg_data_flags { > > + /* page->memcg_data is a pointer to an objcgs vector */ > > + MEMCG_DATA_OBJCGS, > > + /* the next bit after the last actual flag */ > > + __NR_MEMCG_DATA_FLAGS, > > +}; > > + > > +#define MEMCG_DATA_FLAGS_MASK ((0x1UL << __NR_MEMCG_DATA_FLAGS) - 1) > > + > > Nit: > > #define PG_MEMCG_OBJCGS (0x1UL << MEMCG_DATA_OBJCGS) > > and use this macro below. Johannes's pushing on defining flags as bit fields, so I'm sending v4 soon. Thanks!