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Peter Anvin" , Dietmar Eggemann , Steven Rostedt , Ben Segall , Mel Gorman , Valentin Schneider , "Rafael J. Wysocki" , Ricardo Neri , Tim Chen , Mario Limonciello , Meng Li , Huang Rui , "Gautham R. Shenoy" , Thomas Gleixner , Ingo Molnar , Borislav Petkov , Dave Hansen , Peter Zijlstra , Juri Lelli , Vincent Guittot , x86@kernel.org, linux-kernel@vger.kernel.org References: <20241211185552.4553-1-kprateek.nayak@amd.com> <20241211185552.4553-8-kprateek.nayak@amd.com> From: Shrikanth Hegde Content-Language: en-US In-Reply-To: <20241211185552.4553-8-kprateek.nayak@amd.com> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit X-TM-AS-GCONF: 00 X-Proofpoint-GUID: Z2ELeCwGM-SYul3EJjpxmm5ilLdvaR_U X-Proofpoint-ORIG-GUID: OIKc_nmc_xxH4pxCSyVBZ-8RE54qJDn- X-Proofpoint-Virus-Version: vendor=baseguard engine=ICAP:2.0.293,Aquarius:18.0.1051,Hydra:6.0.680,FMLib:17.12.62.30 definitions=2024-10-15_01,2024-10-11_01,2024-09-30_01 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 mlxscore=0 priorityscore=1501 adultscore=0 impostorscore=0 malwarescore=0 phishscore=0 clxscore=1015 mlxlogscore=999 lowpriorityscore=0 suspectscore=0 bulkscore=0 spamscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.19.0-2411120000 definitions=main-2412130103 On 12/12/24 00:25, K Prateek Nayak wrote: > Only set sg_overloaded when computing sg_lb_stats() at the highest sched > domain since rd->overloaded status is updated only when load balancing > at the highest domain. While at it, move setting of sg_overloaded below > idle_cpu() check since an idle CPU can never be overloaded. > > Signed-off-by: K Prateek Nayak > --- > kernel/sched/fair.c | 7 ++++--- > 1 file changed, 4 insertions(+), 3 deletions(-) > > diff --git a/kernel/sched/fair.c b/kernel/sched/fair.c > index ec2a79c8d0e7..3f36805ecdca 100644 > --- a/kernel/sched/fair.c > +++ b/kernel/sched/fair.c > @@ -10358,9 +10358,6 @@ static inline void update_sg_lb_stats(struct lb_env *env, > nr_running = rq->nr_running; > sgs->sum_nr_running += nr_running; > > - if (nr_running > 1) > - *sg_overloaded = 1; > - > if (cpu_overutilized(i)) > *sg_overutilized = 1; Maybe its worth moving the overutilized too after the idle checks. An idle cpu can't be overutilized right? > > @@ -10373,6 +10370,10 @@ static inline void update_sg_lb_stats(struct lb_env *env, > continue; > } > > + /* Overload indicator is only updated at root domain */ > + if (!env->sd->parent && nr_running > 1) > + *sg_overloaded = 1; > + > #ifdef CONFIG_NUMA_BALANCING > /* Only fbq_classify_group() uses this to classify NUMA groups */ > if (sd_flags & SD_NUMA) { Other than the point above, Reviewed-by: Shrikanth Hegde