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charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit X-TM-AS-GCONF: 00 X-Proofpoint-GUID: R6upI6lXY_1d9enpLjyEYx-GKOAltSBv X-Proofpoint-ORIG-GUID: Ohi0sMLgEdApd-thvZEY0z9MiStpX8sA X-Proofpoint-Spam-Details-Enc: AW1haW4tMjUxMTA4MDA5OSBTYWx0ZWRfX0XL6uYOGFHQe iQVAmbP/FrvfyP2xFAYOFtyece7rppL92rmmvcXUMbhBG/D7no9IIQ7WeHQTaOQNK2vk/Yf0y+N 48ZjFTxRoBq1Ov2dkFs6+IHEUaSKnTv/rdeT8F3DrCfbKgDdgs5a1xL9gSERI5Ar7v4bwdrN9pr lhpICimfAn8f6Z3ebOPIbsE1mJT72BRdE2SYNfIIMFW9IsyKVVn+C1ajn9oBQSkF94LvTjfa3Mo 6Khhto6Y5Ro8QT0xw9exllnSCH/Lx8G9SZTGooGB/4bzKQ9PMGifpuJlCmDgV3ohf+VWNMzBnKH BAlKKV9q8J9l9bSPYOMH2uyZhW05fWtwDSVSzgcd5icaMfsJVmHOGVEqwmVQYksuCPB7Pzvq1ZU cixxBQTloSBUQeIOiLA7SMnl1FFUAg== X-Authority-Analysis: v=2.4 cv=V6xwEOni c=1 sm=1 tr=0 ts=69149bac cx=c_pps a=AfN7/Ok6k8XGzOShvHwTGQ==:117 a=AfN7/Ok6k8XGzOShvHwTGQ==:17 a=IkcTkHD0fZMA:10 a=6UeiqGixMTsA:10 a=VkNPw1HP01LnGYTKEx00:22 a=JfrnYn6hAAAA:8 a=4Lv97mECmzqO5O8fzCYA:9 a=QEXdDO2ut3YA:10 a=1CNFftbPRP8L7MoqJWF3:22 a=cPQSjfK2_nFv0Q5t_7PE:22 X-Proofpoint-Virus-Version: vendor=baseguard engine=ICAP:2.0.293,Aquarius:18.0.1121,Hydra:6.1.9,FMLib:17.12.100.49 definitions=2025-11-12_04,2025-11-11_03,2025-10-01_01 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 clxscore=1011 lowpriorityscore=0 adultscore=0 malwarescore=0 impostorscore=0 suspectscore=0 priorityscore=1501 phishscore=0 bulkscore=0 spamscore=0 classifier=typeunknown authscore=0 authtc= authcc= route=outbound adjust=0 reason=mlx scancount=1 engine=8.19.0-2510240000 definitions=main-2511080099 On 11/7/25 9:36 PM, Peter Zijlstra wrote: > Pull out the !sd check to simplify code. > > Signed-off-by: Peter Zijlstra (Intel) > --- > kernel/sched/fair.c | 10 ++++++---- > 1 file changed, 6 insertions(+), 4 deletions(-) > > --- a/kernel/sched/fair.c > +++ b/kernel/sched/fair.c > @@ -12811,14 +12811,16 @@ static int sched_balance_newidle(struct > > rcu_read_lock(); > sd = rcu_dereference_check_sched_domain(this_rq->sd); > + if (!sd) { > + rcu_read_unlock(); > + goto out; > + } > when is sd null? on isol_cpus ? if sd is null, i think we are skipping these compared to earlier. t0 = sched_clock_cpu(this_cpu); sched_balance_update_blocked_averages(this_cpu); > if (!get_rd_overloaded(this_rq->rd) || > - (sd && this_rq->avg_idle < sd->max_newidle_lb_cost)) { > + this_rq->avg_idle < sd->max_newidle_lb_cost) { > > - if (sd) > - update_next_balance(sd, &next_balance); > + update_next_balance(sd, &next_balance); > rcu_read_unlock(); > - > goto out; > } > rcu_read_unlock(); > >