Date:   Mon, 29 Nov 2021 10:01:45 -0800
From:   Roman Gushchin <guro@fb.com>
To:     Waiman Long <longman@redhat.com>
CC:     Johannes Weiner <hannes@cmpxchg.org>,
        Michal Hocko <mhocko@kernel.org>,
        Vladimir Davydov <vdavydov.dev@gmail.com>,
        Andrew Morton <akpm@linux-foundation.org>,
        <linux-kernel@vger.kernel.org>, <cgroups@vger.kernel.org>,
        <linux-mm@kvack.org>, Shakeel Butt <shakeelb@google.com>,
        kernel test robot <lkp@intel.com>
Subject: Re: [PATCH] mm/memcg: Relocate mod_objcg_mlstate(), get_obj_stock()
 and put_obj_stock()
Message-ID: <YaUViaGjXgoLGjUq@carbon.dhcp.thefacebook.com>
References: <20211129161140.306488-1-longman@redhat.com>
Content-Type: text/plain; charset="us-ascii"
Content-Disposition: inline
In-Reply-To: <20211129161140.306488-1-longman@redhat.com>
X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1
X-MS-Exchange-AntiSpam-MessageData-0: =?us-ascii?Q?xyIlWtXX0mxQe1/3dBJCFOKnZzQ9H0UlBtvSkr3CB/0lJeg059ugcIfBi/sl?=
 =?us-ascii?Q?WBDBghpwjbEb1LEtxOWbqTrR7MzM6CtufR1wy5TAlI3Kujo2uXjHCdhMXG92?=
 =?us-ascii?Q?Pn8sPac9g0FTkEKH5SMvQR5UKc5M9TxxX/fQmoIdX9XJFyiyTGCAT+2osxfq?=
 =?us-ascii?Q?93d2673lCV+ndNnEVDjEUEnyH5yYE/CiwZCBYTSJjzTH1VAvSv/ICBVDpLFh?=
 =?us-ascii?Q?JO0u8aXTAWVXss/XcrDPz1IDe5ddYI6FupCOgHW+q6U4GYscFtUO+KCDx2Ol?=
 =?us-ascii?Q?zp9YHiKKCqPvEuR5cOO4ZN58uVDZSG554Wsyrc6bRlAiKmsRFUhviN6dndGr?=
 =?us-ascii?Q?bcDppWTVRy8TnfqDjd+HYm1OBED0NwMzO+itbWULfFUOM3dSYe3h8W+5Kxn1?=
 =?us-ascii?Q?nij4/szSckOMp5t6ohRC8QkUJga4kUMud02q+B9M3L91qbSlVeL5FDwNimM+?=
 =?us-ascii?Q?9lv7eyW3Iz3YS/qH6de2TNxhNOiT6jtJ1Z0HrvtI4QgcNbenLEehYZZ6IS7C?=
 =?us-ascii?Q?wmmBV33i8e8kkkbJYXhlWRq7S9fuViipA4hhthBldY7yJzhpNFZzQyu9vX0l?=
 =?us-ascii?Q?DWPrGBhQizBAlBnNEAUahXMBAdhBhYHBzcPPwPndlPsfgj9Ic9NVEhLzWDvW?=
 =?us-ascii?Q?K6b2b+vxqb2w+/TUXnCocc4wRrmyeU5B5LJXrt2pBxN9lYTpVEAgBUcOFma4?=
 =?us-ascii?Q?8aAsaY3XXPtihyDOUQm+K/QkJsiqjgr0s5pbuEMcgavNRD2eShp8kmPZK2or?=
 =?us-ascii?Q?SbFtJXmewGyJwzE8zSkbG0JmMOCv0C46t2PFwBmXOb+GP6qWHl6rE5LkSO1S?=
 =?us-ascii?Q?ULrA5zIao+UGeC+hyuGZP1YOqgPrXwXSGF2lqSGu5hX82LDBrMHlRb51GAbQ?=
 =?us-ascii?Q?dYhDMG71+e7qughFk/HG7VHKq+7GBFc2Gce9mgAvm+ytdiLJPfiwcXFSm8dm?=
 =?us-ascii?Q?RtkhGLwJEy7k2/baIV9aVMBGwR9G0btH7t2lnZ8dnVw+D3tn+Olmmo5TPLC7?=
 =?us-ascii?Q?QPtqeqPvaHuP4HwlcaaUSmPmmkVM3QdRqqczVZ8akn0gXds1KSxZ6JLxkxg+?=
 =?us-ascii?Q?Fiu1yf+59Mkg0tVRTmFLdUL/k1aGCZUnj0fVmir9SiH7xfQuYEpKs2WrvoCZ?=
 =?us-ascii?Q?r4kk7feP/wLwx2PTAaVHf+bhhCD+Q9N2KA1dXDgW1p2vMphK11ao7H9r5vh3?=
 =?us-ascii?Q?yiMBuLdPMQlb3Bg9wXrF/+RhfBzfEE1bcqg4rXaEhwQNMkfRGe8Td97w0cqV?=
 =?us-ascii?Q?un9swQlVGWClo+2jMo0I9e0HuIM1XEgtxd0mQnqNUMY9BR7nkOVfJChbkiG5?=
 =?us-ascii?Q?34Jrb78RbQHQckgv0pcrVKrf2eIkMuC3f/n15+B6KS6O5ntSH9s7Qk2YhRB3?=
 =?us-ascii?Q?huwisGNPOIjFtSO4xrWifQFjUnVR1vqg82ElCy+2+1XsZEu33YxSis8jNN8h?=
 =?us-ascii?Q?B1sbKWV5jAWqfjLNKRhP9nWC/1Ql45s4iTiCDIWWTjJe2EMoBahbED/V1odW?=
 =?us-ascii?Q?4f8BkP7mIJ3l4HUNtbLSKl+sVQpyIZfvIvlOc0qbVzxO+vCazeczqYYINi4y?=
 =?us-ascii?Q?E7i1AMhuOFaptRPlhuld1IrHlmeZEJMxNpy/8ed1?=
X-MS-Exchange-CrossTenant-Network-Message-Id: 370a436c-f5b7-4c19-d813-08d9b36250b5
X-MS-Exchange-CrossTenant-AuthSource: BYAPR15MB4136.namprd15.prod.outlook.com
X-MS-Exchange-CrossTenant-AuthAs: Internal
X-MS-Exchange-CrossTenant-OriginalArrivalTime: 29 Nov 2021 18:01:49.4246
 (UTC)
X-MS-Exchange-CrossTenant-FromEntityHeader: Hosted
X-MS-Exchange-CrossTenant-Id: 8ae927fe-1255-47a7-a2af-5f3a069daaa2
X-MS-Exchange-CrossTenant-MailboxType: HOSTED
X-MS-Exchange-CrossTenant-UserPrincipalName: v0CBMXle73c6TLXpsCrbhLFqLicCIxaxIIbnNLpuX/fGc6mLsatKyaW5OtVittbT
X-MS-Exchange-Transport-CrossTenantHeadersStamped: BYAPR15MB2342
X-OriginatorOrg: fb.com
X-Proofpoint-GUID: JIcgTnAWm5k3oDvwMyVb8rPtZAasyM1m
X-Proofpoint-ORIG-GUID: JIcgTnAWm5k3oDvwMyVb8rPtZAasyM1m
X-Proofpoint-UnRewURL: 0 URL was un-rewritten
MIME-Version: 1.0
X-Proofpoint-Virus-Version: vendor=baseguard
 engine=ICAP:2.0.205,Aquarius:18.0.790,Hydra:6.0.425,FMLib:17.0.607.475
 definitions=2021-11-29_10,2021-11-28_01,2020-04-07_01
X-Proofpoint-Spam-Details: rule=fb_default_notspam policy=fb_default score=0 impostorscore=0
 malwarescore=0 mlxlogscore=503 lowpriorityscore=0 clxscore=1011
 phishscore=0 mlxscore=0 adultscore=0 bulkscore=0 spamscore=0
 suspectscore=0 priorityscore=1501 classifier=spam adjust=0 reason=mlx
 scancount=1 engine=8.12.0-2110150000 definitions=main-2111290084
X-FB-Internal: deliver
Precedence: bulk
List-ID: <linux-kernel.vger.kernel.org>
X-Mailing-List: linux-kernel@vger.kernel.org

On Mon, Nov 29, 2021 at 11:11:40AM -0500, Waiman Long wrote:
> All the calls to mod_objcg_mlstate(), get_obj_stock() and put_obj_stock()
> are done by functions defined within the same "#ifdef CONFIG_MEMCG_KMEM"
> compilation block. When CONFIG_MEMCG_KMEM isn't defined, the following
> compilation warnings will be issued [1] and [2].
> 
>   mm/memcontrol.c:785:20: warning: unused function 'mod_objcg_mlstate'
>   mm/memcontrol.c:2113:33: warning: unused function 'get_obj_stock'
> 
> Fix these warning by moving those functions to under the same
> CONFIG_MEMCG_KMEM compilation block. There is no functional change.
> 
> [1] https://lore.kernel.org/lkml/202111272014.WOYNLUV6-lkp@intel.com/
> [2] https://lore.kernel.org/lkml/202111280551.LXsWYt1T-lkp@intel.com/
> 
> Fixes: 559271146efc ("mm/memcg: optimize user context object stock access")
> Fixes: 68ac5b3c8db2 ("mm/memcg: cache vmstat data in percpu memcg_stock_pcp")
> Reported-by: kernel test robot <lkp@intel.com>
> Signed-off-by: Waiman Long <longman@redhat.com>

Acked-by: Roman Gushchin <guro@fb.com>

Thanks!