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Shenoy" , Ingo Molnar , Peter Zijlstra , Juri Lelli , Vincent Guittot , linux-kernel@vger.kernel.org References: <20260120113246.27987-1-kprateek.nayak@amd.com> <20260120113246.27987-4-kprateek.nayak@amd.com> <7b0eb351-741b-428a-9bb3-ab0b8a0c81e2@amd.com> Content-Language: en-US From: Shrikanth Hegde In-Reply-To: <7b0eb351-741b-428a-9bb3-ab0b8a0c81e2@amd.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=WMdyn3sR c=1 sm=1 tr=0 ts=6972f455 cx=c_pps a=GFwsV6G8L6GxiO2Y/PsHdQ==:117 a=GFwsV6G8L6GxiO2Y/PsHdQ==:17 a=IkcTkHD0fZMA:10 a=vUbySO9Y5rIA:10 a=VkNPw1HP01LnGYTKEx00:22 a=6QR_KthwZHKoWST7Ih8A:9 a=3ZKOabzyN94A:10 a=QEXdDO2ut3YA:10 X-Proofpoint-GUID: V2KyhQisBmOW1l50Hho7t-WPWntN-tN9 X-Proofpoint-Spam-Details-Enc: AW1haW4tMjYwMTIzMDAyNCBTYWx0ZWRfX2/tMkUGPWaj1 8qQJ0hDFMY79IZZ2ySb1Jj6OZ7IlOE5/QNTvjGNdQff0I9ZDutuU1jQM1NzFwXSYE2d47wB8kIJ 8ED7vPYMOl6nCFOt+VHnhO6bseFXXPFoRR61+FSd+udNmS5bNeedpWYQebpZhmkDuFuCjo3h7qU 1L1/XewlM895N3ax7ILvSqIl4bBATm6BqGrCjVMuWvIhD2v0G5LfzZCrSjaW85ioM5RAAaDGC01 qEwZE1gX/5fztK8aD3kumLIbl3TbDYHmk44gHiUjV5cQfTTOKQENcJjt0PQeG7cTTg69JGdoqAs /XGSa+pJXhi7XECQIAuxlY3nHgbfWjkYsyD/Z5Czv35a6LJe0409KXneRX3848HVV1WjG9+Pt16 tab4qqSa4ry6DJs1YlIr4SJYLg/iV2WJoreAHgaN6xJ5JBTU5TNCAwW+8IUqWlgIkv3W2lr7hcM wcD2FTpdhfTD3iNNjkQ== X-Proofpoint-ORIG-GUID: _JdVWa1tjdCuAZqIHryztCLRC0O4N-TL X-Proofpoint-Virus-Version: vendor=baseguard engine=ICAP:2.0.293,Aquarius:18.0.1121,Hydra:6.1.20,FMLib:17.12.100.49 definitions=2026-01-22_06,2026-01-22_02,2025-10-01_01 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 phishscore=0 malwarescore=0 suspectscore=0 bulkscore=0 adultscore=0 impostorscore=0 spamscore=0 clxscore=1015 priorityscore=1501 lowpriorityscore=0 classifier=typeunknown authscore=0 authtc= authcc= route=outbound adjust=0 reason=mlx scancount=1 engine=8.19.0-2601150000 definitions=main-2601230024 On 1/22/26 2:06 PM, K Prateek Nayak wrote: > Hello Shrikanth, > > On 1/22/2026 1:42 PM, Shrikanth Hegde wrote: >>> @@ -2709,6 +2720,9 @@ build_sched_domains(const struct cpumask *cpu_map, struct sched_domain_attr *att >>>           if (!cpumask_test_cpu(i, cpu_map)) >>>               continue; >>>   +        if (atomic_read(&(*per_cpu_ptr(d.sds, i))->ref)) >>> +            *per_cpu_ptr(d.sds, i) = NULL; >>> + >> >> Can we do this claim_allocations only? > > I didn't do it there since we didn't have reference to the "s_data" > inside claim_allocations(). > > If I remember this right, only init_sched_groups_capacity() has the > requirement to traverse the CPUs in reverse to do > update_group_capacity() when we hit the first CPU in the group. > It doesn't modify the "->ref" of any allocations. > > I can put the claim_allocations() bits the previous loop and pass the > CPU and the s_data reference so it can free both "d.sds" and all the > "d.sd" bits in one place and retain this reverse loop for > init_sched_groups_capacity(). Does that sound better? > Yes.IMO Having it in one place is better. Even the next loop could be used to do that. >> sdt_alloc and free is complicated already. >> >>>           for (sd = *per_cpu_ptr(d.sd, i); sd; sd = sd->parent) { >>>               claim_allocations(i, sd); >>>               init_sched_groups_capacity(i, sd); >> >