group_cpus_evenly(9)

💖 group_cpus_evenly(9) 💖

okay so bestie, welcome to the group_cpus_evenly(9) page — yes that (9) is the manual section, it's giving kernel-API royalty 👑 — and honestly this little function is lowkey iconic for what it does: grouping all your CPUs evenly per NUMA/CPU locality. no cap. 🦋

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✨ NAME ✨

group_cpus_evenly — group all CPUs evenly per NUMA/CPU locality, fr fr 💅

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🌸 SYNOPSIS 🌸

struct cpumask * group_cpus_evenly (unsigned int numgrps , unsigned int
*nummasks );

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🎀 ARGUMENTS 🎀

• numgrps — the number of groups. that's it, that's the whole vibe. 🍓
• nummasks — the number of initialized cpumasks. 🧚

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⭐ RETURN ⭐

you get a cpumask array if it works — slay 💅 — and NULL otherwise 😭. and each element includes the CPUs assigned to this group, so every mask knows exactly who's in its squad 🫶.

also: nummasks contains the number of initialized masks, which can be less than numgrps. yes, less. don't come for me, that's just how it is. 🙈

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🌈 DESCRIPTION 🌈

the whole mission here is to try to put close CPUs — close from the viewpoint of CPU and NUMA locality — into the same group 💜. and it does it with a two-stage grouping, main character energy only:

1. allocate present CPUs on these groups evenly first ⭐
2. allocate other possible CPUs on these groups evenly ✨

and here's the guarantee, written in stone, no take-backs: in the resulted grouping, all CPUs are covered, and no same CPU is assigned to multiple groups. periodt. 💀🔥

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🦋 SEE ALSO 🦋

• Kernel file ./lib/group_cpus.c — go read the source, iykyk 👑

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and that's the whole page bestie, mwah 💖 — this cutie came from ./lib, dated October 2026, and it goes by group_cpus_evenly(9). take care of her 🎀🌸