arch_set_cpu_capacity(9)

💅 arch_set_cpu_capacity — from the Kernel API Manual, section 9 🎀

okay bestie, listen up, because this one is lowkey adorable and also deeply relevant to your hybrid CPU era ✨

🌸 NAME 🌸

arch_set_cpu_capacity — set the scale-invariance parameters for a CPU 🦋 literally what it says on the tin, no cap

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✨ SYNOPSIS ✨

void arch_set_cpu_capacity (int cpu , unsigned long cap , unsigned long
max_cap , unsigned long cap_freq , unsigned long base_freq );

that's it, that's the whole vibe check 💅 five arguments, returns void, absolutely giving "I just fill in the numbers and go" energy 🙈

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💖 ARGUMENTS 💖

• cpu — the target CPU 🎯 like, the one you're talking about, be specific bestie
• cap — how much capacity cpu has at its maximum frequency, measured relative to max_cap 🔥
• max_cap — the system-wide maximum CPU capacity 👑 the big one, the ceiling, the main character
• cap_freq — the frequency of cpu that corresponds to cap ⚡
• base_freq — the frequency of cpu at which MPERF counts 🌈 yes, MPERF, it's a real thing, iykyk

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🧚 DESCRIPTION 🧚

okay so here's the tea 🍓 the units you use for cap and max_cap genuinely do not matter — like, use potatoes, use vibes, use whatever — as long as they're consistent with each other, because cap is effectively divided by max_cap anyway. the ratio is what eats, not the units 💅✨

and it's the exact same story for cap_freq and base_freq — analogous, consistent, that's the whole rule 📏 two little pairs, each pair just has to agree with itself.

⭐ then, after you've called this for all the CPUs, call arch_rebuild_sched_domains so the scheduler knows capacity-aware scheduling can be used going forward 🫶 like, that's the official handoff, don't skip it, the scheduler is waiting for the text back 😭

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🦋 SEE ALSO 🦋

• Kernel file ./arch/x86/kernel/cpu/aperfmperf.c 📁
• arch_enable_hybrid_capacity_scale(9) 💜

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and that's the page, bestie!! brought to you by ./arch/x86/kernel/cpu, dated October 2026 🗓️💖 go forth and scale your invariances, mwah 😘🎀