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charset=UTF-8 Date: Fri, 26 Jun 2026 14:52:08 -0400 Message-Id: From: "Zi Yan" Subject: Re: [PATCH v2 3/6] mm/page_owner: hoist CONFIG_MEMCG to function level for print_page_owner_memcg() Cc: "Suren Baghdasaryan" , "Michal Hocko" , "Brendan Jackman" , "Johannes Weiner" , , To: "Ye Liu" , "Andrew Morton" , "Vlastimil Babka" X-Mailer: aerc 0.21.0 References: <20260626024550.25677-1-ye.liu@linux.dev> <20260626024550.25677-4-ye.liu@linux.dev> In-Reply-To: <20260626024550.25677-4-ye.liu@linux.dev> X-ClientProxiedBy: BLAPR03CA0097.namprd03.prod.outlook.com (2603:10b6:208:32a::12) To IA0PR12MB8374.namprd12.prod.outlook.com (2603:10b6:208:40e::7) Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-MS-PublicTrafficType: Email X-MS-TrafficTypeDiagnostic: IA0PR12MB8374:EE_|CH3PR12MB7666:EE_ X-MS-Office365-Filtering-Correlation-Id: ed4007ed-9976-4c6c-6e12-08ded3b40661 X-MS-Exchange-SenderADCheck: 1 X-MS-Exchange-AntiSpam-Relay: 0 X-Microsoft-Antispam: BCL:0;ARA:13230040|376014|366016|1800799024|23010399003|22082099003|18002099003|4143699003|11063799006|56012099006; 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Maybe just remove "no-op" in the commit message to avoid confusion. > { return ret; } when the config is disabled. Hoist the #ifdef to the > top level so the real implementation and the empty stub are two clearly > separated definitions. > > No functional change. > > Signed-off-by: Ye Liu > --- > mm/page_owner.c | 10 ++++++++-- > 1 file changed, 8 insertions(+), 2 deletions(-) > > +#else > +static inline int print_page_owner_memcg(char *kbuf, size_t count, int r= et, > + struct page *page) > +{ > + return ret; It is not obvious why we need to return ret here, until I find that ret cumulates scnprintf() return values. > +} > +#endif > =20 > static ssize_t > print_page_owner(char __user *buf, size_t count, unsigned long pfn, LGTM. Reviewed-by: Zi Yan --=20 Best Regards, Yan, Zi