Hi, With core scheduling LTP reports 2 new failures related to cgroups(memcg_stat_rss and memcg_move_charge_at_immigrate). I will try to debug it.
Also "perf sched map" indicates there might be a small window when 2 processes in different cgroups run together on one core. In below case B0 and D0(stress-ng-cpu and sysbench) belong to 2 different cgroups with cpu.tag enabled. $ perf sched map *A0 382.266600 secs A0 => kworker/0:1-eve:51 *B0 382.266612 secs B0 => stress-ng-cpu:7956 *A0 382.394597 secs *B0 382.394609 secs B0 *C0 382.494459 secs C0 => i915/signal:0:450 B0 *D0 382.494468 secs D0 => sysbench:8088 *. D0 382.494472 secs . => swapper:0 . *C0 383.095787 secs *B0 C0 383.095792 secs B0 *D0 383.095820 secs *A0 D0 383.096587 secs In some cases I dont see an IPI getting sent to sibling cpu when 2 incompatible processes are picked. Like is below logs at timestamp 382.146250 "stress-ng-cpu" is picked when "sysbench" is running on the sibling cpu. kworker/0:1-51 [000] d... 382.146246: __schedule: cpu(0): selected: stress-ng-cpu/7956 ffff9945bad29200 kworker/0:1-51 [000] d... 382.146246: __schedule: max: stress-ng-cpu/7956 ffff9945bad29200 kworker/0:1-51 [000] d... 382.146247: __prio_less: (swapper/4/0;140,0,0) ?< (sysbench/8088;140,34783671987,0) kworker/0:1-51 [000] d... 382.146248: __prio_less: (stress-ng-cpu/7956;119,34817170203,0) ?< (sysbench/8088;119,34783671987,0) kworker/0:1-51 [000] d... 382.146249: __schedule: cpu(4): selected: sysbench/8088 ffff9945a7405200 kworker/0:1-51 [000] d... 382.146249: __prio_less: (stress-ng-cpu/7956;119,34817170203,0) ?< (sysbench/8088;119,34783671987,0) kworker/0:1-51 [000] d... 382.146250: __schedule: picked: stress-ng-cpu/7956 ffff9945bad29200 kworker/0:1-51 [000] d... 382.146251: __switch_to: Pawan: cpu(0) switching to stress-ng-cpu kworker/0:1-51 [000] d... 382.146251: __switch_to: Pawan: cpu(4) running sysbench stress-ng-cpu-7956 [000] dN.. 382.274234: __schedule: cpu(0): selected: kworker/0:1/51 0 stress-ng-cpu-7956 [000] dN.. 382.274235: __schedule: max: kworker/0:1/51 0 stress-ng-cpu-7956 [000] dN.. 382.274235: __schedule: cpu(4): selected: sysbench/8088 ffff9945a7405200 stress-ng-cpu-7956 [000] dN.. 382.274237: __prio_less: (kworker/0:1/51;119,50744489595,0) ?< (sysbench/8088;119,34911643157,0) stress-ng-cpu-7956 [000] dN.. 382.274237: __schedule: picked: kworker/0:1/51 0 stress-ng-cpu-7956 [000] d... 382.274239: __switch_to: Pawan: cpu(0) switching to kworker/0:1 stress-ng-cpu-7956 [000] d... 382.274239: __switch_to: Pawan: cpu(4) running sysbench -Pawan
