On 22/02/18 11:01, Andrii Anisov wrote:

On 22.02.18 12:33, bharat gohil wrote:
System got hand and I got following traces related to energy aware scheduler. Is Xen affected with guest scheduling mechanism? I have SoC which has 4-Cortex A35 and 2-Cortex A72.

[    0.202545] Xen: initializing cpu4
[    0.202562] Invalid sched_group_energy for CPU4
[    0.202564] CPU4: update cpu_capacity 1024
[    0.202566] CPU4: Booted secondary processor [410fd041]
[    0.230197] Detected PIPT I-cache on CPU5
[    0.230202] CPU features: SANITY CHECK: Unexpected variation in SYS_ID_AA64MMFR0_EL1. Boot CPU: 0x00000000101122, CPU5: 0x00000000001124
[    0.230250] Xen: initializing cpu5
[    0.230264] Invalid sched_group_energy for CPU5
[    0.230265] CPU5: update cpu_capacity 1024
[    0.230267] CPU5: Booted secondary processor [410fd041]
[    0.230373] Brought up 6 CPUs
[    0.234084] SMP: Total of 6 processors activated.
[    0.234108] CPU features: detected feature: 32-bit EL0 Support
[    0.234382] CPU: All CPU(s) started at EL1
[    0.234627] Invalid sched_group_energy for CPU5
[    0.234662] CPU5: update max cpu_capacity 1024
[    0.234680] Invalid sched_group_energy for Cluster5
[    0.234698] Invalid sched_group_energy for CPU4
[    0.234715] Invalid sched_group_energy for Cluster4
[    0.234733] Invalid sched_group_energy for CPU3
[    0.234750] Invalid sched_group_energy for Cluster3
[    0.234767] Invalid sched_group_energy for CPU2
[    0.234784] Invalid sched_group_energy for Cluster2
[    0.234801] Invalid sched_group_energy for CPU1
[    0.234819] Invalid sched_group_energy for Cluster1
[    0.234836] Invalid sched_group_energy for CPU0
[    0.234853] Invalid

I have SoC with 4 Cortex A35 and 2 Cortex A72.
There is a nit which is overlooked often: XEN hypervisor does not pass an input device tree as is to Dom0. Especially CPU and memory nodes. They are created by XEN itself accordingly to dom0 configuration. Literally Dom0 receives device tree with VCPUs and domain RAM space description instead of PCPUs and machine RAM description. In your particular case, I guess, scheduler is looking for some specific properties in CPU nodes, but do not find them, because XEN creates basic CPU nodes from the scratch.

That's just a red-herring. You should never hang because of missing properties for the CPU scheduling.

--
Julien Grall

_______________________________________________
Xen-devel mailing list
Xen-devel@lists.xenproject.org
https://lists.xenproject.org/mailman/listinfo/xen-devel

Reply via email to