scx_bpf_cpuperf_set(9)

okay so bestie, welcome to scx_bpf_cpuperf_set(9) from the Kernel API Manual — it’s giving “tell a CPU what relative performance target to aim for” energy 💅✨

✨ NAME ✨

scx_bpf_cpuperf_set — Set the relative performance target of a CPU, periodt. That’s the whole name, no cap 💖

💖 SYNOPSIS 💖

the signature is literally right here — copy it exactly, because spelling counts bestie:

__bpf_kfunc void scx_bpf_cpuperf_set (s32 cpu , u32 perf , const struct
       bpf_prog_aux *aux );

🎀 ARGUMENTS 🎀

• cpu — the CPU of interest 🌸
• perf — the target performance level, and it lives in the range [0, SCX_CPUPERF_ONE] 💖
• aux — the implicit BPF argument to access bpf_prog_aux, hidden from BPF progs 🙈 so yes, it’s a backstage-pass situation

💅 DESCRIPTION 💅

Set the target performance level of cpu to perf — that’s the move. perf is in a linear relative scale between 0 and SCX_CPUPERF_ONE. This determines how the schedutil cpufreq governor chooses the target frequency. Slay 💅

Real talk though: the actual performance level chosen, CPU grouping, and the overhead and latency of the operations are dependent on the hardware and cpufreq driver in use 🔍. So consult hardware and cpufreq documentation for more information — they’re the ones with the receipts. The current performance level can be monitored using scx_bpf_cpuperf_cur — iconique 🦋

🦋 SEE ALSO 🦋

go read these too, iykyk 💜 — and yeah, the kernel file is part of the vibe:

• Kernel file ./kernel/sched/ext/ext.c
• scx_is_descendant(9), rq_is_open(9), scx_fill_cmask_scratch(9), scx_call_op_set_cpumask(9), nldsq_next_task(9)
• nldsq_cursor_next_task(9), nldsq_cursor_lost_task(9), scx_task_iter_start(9), scx_task_iter_unlock(9), scx_task_iter_relock(9)
• scx_task_iter_stop(9), scx_task_iter_next(9), scx_task_iter_next_locked(9), scx_dump_event(9), wait_ops_state(9)
• scx_cpu_valid(9), schedule_deferred(9), schedule_deferred_locked(9), dsq_insert_head(9), set_task_slice_keep_oob(9)
• scx_task_slice_ended(9), move_remote_task_to_local_dsq(9), unlink_dsq_and_switch_rq_lock(9), move_task_between_dsqs(9), dispatch_to_local_dsq(9)
• finish_dispatch(9), scx_prio_less(9), __scx_init_task(9), task_dead_and_done(9), scx_tg_sched(9)
• scx_tg_knob_sched(9), handle_lockup(9), scx_rcu_cpu_stall(9), scx_softlockup(9), scx_hardlockup(9)
• unbypass_renotify_idle(9), scx_bypass(9), scx_propagate_exit_irq_workfn(9), scx_flush_disable_work(9), print_scx_info(9)
• scx_bpf_dsq_insert___v2(9), __scx_bpf_dsq_insert_vtime(9), scx_bpf_dispatch_nr_slots(9), scx_bpf_dispatch_cancel(9), scx_bpf_dsq_move_to_local___v2(9)
• scx_bpf_dsq_move_set_slice(9), scx_bpf_dsq_move_set_vtime(9), scx_bpf_dsq_move(9), scx_bpf_dsq_move_vtime(9), scx_bpf_reenqueue_local(9)
• scx_bpf_create_dsq(9), scx_bpf_task_set_slice(9), scx_bpf_task_set_dsq_vtime(9), scx_bpf_kick_cpu(9), scx_bpf_kick_cid(9)
• scx_bpf_dsq_nr_queued(9), scx_bpf_destroy_dsq(9), bpf_iter_scx_dsq_new(9), bpf_iter_scx_dsq_next(9), bpf_iter_scx_dsq_destroy(9)
• scx_bpf_dsq_peek(9), scx_bpf_dsq_reenq(9), scx_bpf_reenqueue_local___v2(9), scx_bpf_exit_bstr(9), scx_bpf_error_bstr(9)
• scx_bpf_dump_bstr(9), scx_bpf_cpuperf_cap(9), scx_bpf_cidperf_cap(9), scx_bpf_cpuperf_cur(9), scx_bpf_cidperf_cur(9)
• scx_bpf_cidperf_set(9), scx_bpf_nr_node_ids(9), scx_bpf_nr_cpu_ids(9), scx_bpf_nr_cids(9), scx_bpf_nr_online_cids(9)
• scx_bpf_online_cmask(9), scx_bpf_this_cid(9), scx_bpf_get_possible_cpumask(9), scx_bpf_get_online_cpumask(9), scx_bpf_put_cpumask(9)
• scx_bpf_task_running(9), scx_bpf_task_cpu(9), scx_bpf_task_cid(9), scx_bpf_locked_rq(9), scx_bpf_cpu_curr(9)
• scx_bpf_cid_curr(9), scx_bpf_tid_to_task(9), scx_bpf_now(9), scx_bpf_events(9), scx_bpf_task_cgroup(9)

🫶 that’s the whole page, bestie — it lives in ./kernel/sched/ext, dated October 2026, and it’s titled scx_bpf_cpuperf_set(9) — byeee 💋✨