scx_p2dp: runtime error (SCX_DSQ_LOCAL[_ON] target CPU 23 not allowed for stress-ng-cpu-s[410085]) when exercising with stress-ng --cpu-sched 0 #2879
Description
Hitting an issue running 6.17 kernel on Debian 13 (trixie) with latest scx_p2dp scheduler on a 24 thread Intel(R) Core(TM) Ultra 9 285K with the following:
git clone https://github.com/colinianking/stress-ng
cd stress-ng
make -j $(nproc)
then run:
./stress-ng --cpu-sched 0 -t 60
and we get:
sudo ./target/release/scx_p2dq
14:51:39 [INFO] Running scx_p2dq (build ID: 1.0.22-g894c0015 x86_64-unknown-linux-gnu)
14:51:39 [INFO] DSQ[0] slice_ns 100000
14:51:39 [INFO] DSQ[1] slice_ns 3200000
14:51:39 [INFO] DSQ[2] slice_ns 6400000
14:51:39 [WARN] libbpf: map 'p2dq': BPF map skeleton link is uninitialized
14:51:39 [INFO] P2DQ scheduler started! Run `scx_p2dq --monitor` for metrics.
DEBUG DUMP
================================================================================
migration/0[18] triggered exit kind 1024:
runtime error (SCX_DSQ_LOCAL[_ON] target CPU 23 not allowed for stress-ng-cpu-s[410085])
Backtrace:
scx_exit+0x58/0x80
task_can_run_on_remote_rq+0xcc/0x190
dispatch_to_local_dsq+0x75/0x2e0
process_ddsp_deferred_locals+0x9c/0x130
deferred_irq_workfn+0x33/0x60
irq_work_single+0x34/0x90
irq_work_run_list+0x4c/0x70
irq_work_run+0x20/0x50
__sysvec_irq_work+0x4c/0x220
sysvec_irq_work+0xa0/0xd0
asm_sysvec_irq_work+0x1a/0x20
finish_task_switch.isra.0+0x126/0x4d0
__schedule+0x84c/0x1770
schedule+0x37/0x120
smpboot_thread_fn+0x33c/0x490
kthread+0x1a4/0x3e0
ret_from_fork+0x2b8/0x3a0
ret_from_fork_asm+0x1a/0x30
CPU states
----------
CPU 0 : nr_run=6 flags=0x1 cpu_rel=1 ops_qseq=470708 pnt_seq=285208
curr=migration/0[18] class=rt_sched_class
R stress-ng-cpu-s[410087] +0ms
scx_state/flags=3/0x9 dsq_flags=0x1 ops_state/qseq=0/0
sticky/holding_cpu=-1/-1 dsq_id=0x800
dsq_vtime=6664809417 slice=100000 weight=1
cpus=000001
asm_sysvec_reschedule_ipi+0x1a/0x20
R stress-ng-cpu-s[410091] +0ms
scx_state/flags=3/0x9 dsq_flags=0x1 ops_state/qseq=0/0
sticky/holding_cpu=-1/-1 dsq_id=0x800
dsq_vtime=6664981874 slice=100000 weight=1
cpus=000001
x64_sys_call+0x1b7d/0x41b0
do_syscall_64+0xcf/0x5c0
entry_SYSCALL_64_after_hwframe+0x71/0x79
R stress-ng-cpu-s[410093] +0ms
scx_state/flags=3/0x9 dsq_flags=0x1 ops_state/qseq=0/0
sticky/holding_cpu=-1/-1 dsq_id=0x800
dsq_vtime=6664948323 slice=100000 weight=1
cpus=000001
common_nsleep+0x3f/0x60
__x64_sys_clock_nanosleep+0xec/0x180
x64_sys_call+0x38af/0x41b0
do_syscall_64+0xcf/0x5c0
entry_SYSCALL_64_after_hwframe+0x71/0x79
R stress-ng-cpu-s[410095] +0ms
scx_state/flags=3/0x9 dsq_flags=0x1 ops_state/qseq=0/0
sticky/holding_cpu=-1/-1 dsq_id=0x800
dsq_vtime=6665464674 slice=100000 weight=1
cpus=000001
do_syscall_64+0x4d7/0x5c0
entry_SYSCALL_64_after_hwframe+0x71/0x79
R stress-ng-cpu-s[410089] +0ms
scx_state/flags=3/0x9 dsq_flags=0x1 ops_state/qseq=0/0
sticky/holding_cpu=-1/-1 dsq_id=0x800
dsq_vtime=6664948323 slice=100000 weight=1
cpus=000001
x64_sys_call+0x1b7d/0x41b0
do_syscall_64+0xcf/0x5c0
entry_SYSCALL_64_after_hwframe+0x71/0x79
R stress-ng-cpu-s[410085] +0ms
scx_state/flags=3/0x1 dsq_flags=0x0 ops_state/qseq=0/0
sticky/holding_cpu=-1/-1 dsq_id=0x8000000000000001
dsq_vtime=6665159525 slice=100000 weight=1
cpus=000001
__set_cpus_allowed_ptr_locked+0x205/0x2d0
__set_cpus_allowed_ptr+0x78/0x100
__sched_setaffinity+0x14c/0x360
sched_setaffinity+0x28d/0x360
__x64_sys_sched_setaffinity+0xd3/0x100
x64_sys_call+0x2737/0x41b0
do_syscall_64+0xcf/0x5c0
entry_SYSCALL_64_after_hwframe+0x71/0x79
CPU 8 : nr_run=1 flags=0x9 cpu_rel=0 ops_qseq=334200 pnt_seq=367711
curr=stress-ng-cpu-s[410083] class=ext_sched_class
*R stress-ng-cpu-s[410083] +0ms
scx_state/flags=3/0xd dsq_flags=0x0 ops_state/qseq=0/0
sticky/holding_cpu=-1/-1 dsq_id=(n/a)
dsq_vtime=6656082848 slice=20000000 weight=100
cpus=000100
Event counters
--------------
SCX_EV_SELECT_CPU_FALLBACK: 0
SCX_EV_DISPATCH_LOCAL_DSQ_OFFLINE: 0
SCX_EV_DISPATCH_KEEP_LAST: 5468
SCX_EV_ENQ_SKIP_EXITING: 0
SCX_EV_ENQ_SKIP_MIGRATION_DISABLED: 1
SCX_EV_REFILL_SLICE_DFL: 5465
SCX_EV_BYPASS_DURATION: 51431080
SCX_EV_BYPASS_DISPATCH: 0
SCX_EV_BYPASS_ACTIVATE: 1
================================================================================