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Shenoy" , Vincent Guittot , Juri Lelli , Dietmar Eggemann , Steven Rostedt , Ben Segall , Mel Gorman , Valentin Schneider , Hillf Danton , Shrikanth Hegde , Jianyong Wu , Yangyu Chen , Tingyin Duan , Vern Hao , Vern Hao , Len Brown , Aubrey Li , Zhao Liu , Chen Yu , Chen Yu , Adam Li , Aaron Lu , Tim Chen , Josh Don , Gavin Guo , Qais Yousef , Libo Chen , linux-kernel@vger.kernel.org, Madadi Vineeth Reddy References: <6ec6eee6e1c620c0cfb9f56923f8bfbb71c31a75.1770760558.git.tim.c.chen@linux.intel.com> Content-Language: en-US From: Madadi Vineeth Reddy In-Reply-To: <6ec6eee6e1c620c0cfb9f56923f8bfbb71c31a75.1770760558.git.tim.c.chen@linux.intel.com> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit X-TM-AS-GCONF: 00 X-Proofpoint-Reinject: loops=2 maxloops=12 X-Proofpoint-GUID: j4hVK9TreTZRCRJg0Ff6guU2C_vYwvVq X-Proofpoint-Spam-Details-Enc: AW1haW4tMjYwMjE0MDA5OCBTYWx0ZWRfXxsTGKvfaEud6 TKeBK7SwbLan1f1MFdPgCfkWNCx0VRCYSXEIERwkoSGVdE/+WE1x03LVUF6NJ51oeosG+xYc2E6 hVia3YxqPkKeq72kxIg9V0NzuSQ4/wF3c1YxhTT5GUqO/T3Q+3fg6+nG8AFJq/0wBe50ExZ2SR5 Cs/5s4+VD4EZOP/F1A0MPr+ASI01lxxEZZw7ov7tDSM+B8tRmspN5oCYKblL7wqW5LVTdPI6kib Q5ebrIaXnIqGkakBHJlbkcLIOWvGpbGXoGdcnF7toj1pYgVmcspZw/TdiKeRBuk2WQz211MRh55 Jh2DEao6IUovf47aFRBEXZuQt07bGMQKNxHCt1WbR07UHQo4kj/LMCjwR8HQRcvCd8Kdke0scnU GRTp8Xo0trSawrKbWMuOTNAQxbKYE/Em0pm5//bfOqdZjAgt5pMlqtQTIUjUEsvG/bptqIWJzGB KTb1aCxnbte9bPloCdA== X-Authority-Analysis: v=2.4 cv=UPXQ3Sfy c=1 sm=1 tr=0 ts=699069f5 cx=c_pps a=GFwsV6G8L6GxiO2Y/PsHdQ==:117 a=GFwsV6G8L6GxiO2Y/PsHdQ==:17 a=IkcTkHD0fZMA:10 a=HzLeVaNsDn8A:10 a=VkNPw1HP01LnGYTKEx00:22 a=Mpw57Om8IfrbqaoTuvik:22 a=GgsMoib0sEa3-_RKJdDe:22 a=JfrnYn6hAAAA:8 a=B7_WRAFxAQ09rwHV_JsA:9 a=QEXdDO2ut3YA:10 a=1CNFftbPRP8L7MoqJWF3:22 X-Proofpoint-ORIG-GUID: qx2ra5fnD2I0KGPKFxCd_Tw5HmSHmrAa X-Proofpoint-Virus-Version: vendor=baseguard engine=ICAP:2.0.293,Aquarius:18.0.1121,Hydra:6.1.51,FMLib:17.12.100.49 definitions=2026-02-14_01,2026-02-13_01,2025-10-01_01 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 malwarescore=0 suspectscore=0 phishscore=0 impostorscore=0 adultscore=0 bulkscore=0 clxscore=1011 lowpriorityscore=0 priorityscore=1501 spamscore=0 classifier=typeunknown authscore=0 authtc= authcc= route=outbound adjust=0 reason=mlx scancount=1 engine=8.22.0-2601150000 definitions=main-2602140098 Hi Tim, Thanks for the patch series. On 11/02/26 03:48, Tim Chen wrote: > From: "Peter Zijlstra (Intel)" > > Adds infrastructure to enable cache-aware load balancing, > which improves cache locality by grouping tasks that share resources > within the same cache domain. This reduces cache misses and improves > overall data access efficiency. [..snip..] > +void mm_init_sched(struct mm_struct *mm, > + struct sched_cache_time __percpu *_pcpu_sched) > +{ > + unsigned long epoch; > + int i; > + > + for_each_possible_cpu(i) { > + struct sched_cache_time *pcpu_sched = per_cpu_ptr(_pcpu_sched, i); > + struct rq *rq = cpu_rq(i); > + > + pcpu_sched->runtime = 0; > + pcpu_sched->epoch = rq->cpu_epoch; > + epoch = rq->cpu_epoch; Shouldn't cpu_epoch be read under cpu_epoch_lock, similar to how fraction_mm_sched() and __update_mm_sched() acquire the lock before accessing this field? Thanks, Vineeth > + } > + > + raw_spin_lock_init(&mm->sc_stat.lock); > + mm->sc_stat.epoch = epoch; > + mm->sc_stat.cpu = -1; > + > + /* > + * The update to mm->sc_stat should not be reordered > + * before initialization to mm's other fields, in case > + * the readers may get invalid mm_sched_epoch, etc. > + */ > + smp_store_release(&mm->sc_stat.pcpu_sched, _pcpu_sched); > +} [..snip..]