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To: David Hildenbrand , Andrew Morton , Oscar Salvador Cc: Ritesh Harjani , Aboorva Devarajan , linux-mm@kvack.org, linux-kernel@vger.kernel.org, Madhavan Srinivasan , linuxppc-dev@lists.ozlabs.org, Christophe Leroy , Peter Zijlstra , Ingo Molnar , x86@kernel.org, Greg Kroah-Hartman , Danilo Krummrich , Mike Rapoport , Dave Jiang References: <40257b5228dec05e5b252f02438608eb8d681a2d.1758736423.git.donettom@linux.ibm.com> <0de65980-4333-434a-ae7d-2b7be46c2cca@redhat.com> Content-Language: en-US From: Donet Tom In-Reply-To: <0de65980-4333-434a-ae7d-2b7be46c2cca@redhat.com> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 8bit X-TM-AS-GCONF: 00 X-Authority-Analysis: v=2.4 cv=J5Cq7BnS c=1 sm=1 tr=0 ts=68d541b9 cx=c_pps a=3Bg1Hr4SwmMryq2xdFQyZA==:117 a=3Bg1Hr4SwmMryq2xdFQyZA==:17 a=IkcTkHD0fZMA:10 a=yJojWOMRYYMA:10 a=VnNF1IyMAAAA:8 a=VYFwuNkCapB6VMV0qykA:9 a=3ZKOabzyN94A:10 a=QEXdDO2ut3YA:10 X-Proofpoint-GUID: eMJ9kfsTgBHfUA6tVjsPD_AWFt_ZESvP X-Proofpoint-Spam-Details-Enc: AW1haW4tMjUwOTIwMDAxNSBTYWx0ZWRfX+DZTcBF17QFy MJGsSw1/Ma0YcTsS42Ta3NR9/1joRq7IOGTZXo+cwc7aZJbzUJaXRGPwCwXFwuM+5/jWjBD3dGt Tk3EDAfcN5i38vmODxWFcPGltZX9kTTCvdfCWV5Z2NlFgWxLa3oNm8+pcfJStpZdKE4Gwq4VzTW sJkAMrOXpfc63gthcVes50j/iqweKkELJ+x7YU7uusmeyGQQM4aLq2c9fE6Q/+dJnIN9dW6NSqH AuG+1nW9L2yAudJXxgTbhdYL5s28+10xdlW+KchgLU06UsGP3EjqQ3uF17XkO5GnpYdm+UdF2lJ oJQnlNNoBPLQbNRziKFEx7Bv4ftMtntnWH6VzCAs+NzzZ999TiM1Wk2/8vuMLaY4Zv54febI3Ms KxIRK8rA X-Proofpoint-ORIG-GUID: Dk6YoM9jUnqj7o99btFxGm_iPC6WbMWr X-Proofpoint-Virus-Version: vendor=baseguard engine=ICAP:2.0.293,Aquarius:18.0.1117,Hydra:6.1.9,FMLib:17.12.80.40 definitions=2025-09-25_01,2025-09-25_01,2025-03-28_01 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 priorityscore=1501 impostorscore=0 malwarescore=0 spamscore=0 bulkscore=0 phishscore=0 clxscore=1015 adultscore=0 suspectscore=0 classifier=typeunknown authscore=0 authtc= authcc= route=outbound adjust=0 reason=mlx scancount=1 engine=8.19.0-2507300000 definitions=main-2509200015 On 9/25/25 2:24 PM, David Hildenbrand wrote: > On 24.09.25 20:40, Donet Tom wrote: >> register_one_node() and register_node() are small functions. >> This patch merges them into a single function named register_node() >> to improve code readability. >> >> No functional changes are introduced. >> >> Signed-off-by: Donet Tom >> --- > > [...] > >>   /** >>    * unregister_node - unregister a node device >>    * @node: node going away >> @@ -869,7 +842,13 @@ void >> register_memory_blocks_under_node_hotplug(int nid, unsigned long >> start_pfn, >>   } >>   #endif /* CONFIG_MEMORY_HOTPLUG */ >>   -int register_one_node(int nid) >> +/* > > We can directly convert this to proper kernel doc by using /** > Sure I will add it. > >> + * register_node - Setup a sysfs device for a node. >> + * @nid - Node number to use when creating the device. >> + * >> + * Initialize and register the node device. > > and briefly describing what the return value means > > "Returns 0 on success, ..." > Sure >> + */ >> +int register_node(int nid) >>   { >>       int error; >>       int cpu; >> @@ -880,14 +859,23 @@ int register_one_node(int nid) >>           return -ENOMEM; >>         INIT_LIST_HEAD(&node->access_list); >> -    node_devices[nid] = node; >>   -    error = register_node(node_devices[nid], nid); >> +    node->dev.id = nid; >> +    node->dev.bus = &node_subsys; >> +    node->dev.release = node_device_release; >> +    node->dev.groups = node_dev_groups; >> + >> +    error = device_register(&node->dev); >>       if (error) { >> -        node_devices[nid] = NULL; > > Wondering why we did have this temporary setting of the node_devices[] > in there. But I cannot immediately spot why it was required. node_devices[] is used in many places to access node data. In the previous code, immediately after allocating the node structure, it was stored in node_devices[]. On error paths, we were clearing the node structure entry from node_devices[]. With the new code, the node structure is now stored in node_devices[] only after the device has been registered, and just before calling register_cpu_under_node(), since node_devices[] is accessed inside that function. It is also used outside of node.c, in hugetlb_register_all_nodes() . Do you think we could use a different mechanism instead of this?