smp_call_function_any(9)

💖 NAME 💖

smp_call_function_any(9) — okay bestie, this is literally “Run a function on any of the given cpus,” no cap. The manual page is from the Kernel API Manual, and it’s here to help you pick a CPU and run your function on it. ✨

✨ SYNOPSIS ✨

int smp_call_function_any (const struct cpumask *mask , smp_call_func_t
       func , void *info , int wait );

🎀 ARGUMENTS 🎀

• mask — The mask of cpus it can run on. It’s giving “these are the allowed CPUs” energy. 💅
• func — The function to run. This must be fast and non-blocking. Seriously, bestie, fast and non-blocking is the vibe check here. ⚡
• info — An arbitrary pointer to pass to the function. It’s just your little note to hand over. 🫶
• wait — If true, wait until function has completed. If you’re the patient main character, this is for you. 😌

🌸 DESCRIPTION 🌸

Selection preference, in this exact order:

1. current cpu if in mask
2. nearest cpu in mask, based on NUMA topology

So the picker is like, “current CPU first if it’s allowed, otherwise closest CPU by NUMA topology.” Lowkey iconic CPU matchmaking. 🧚

🔥 RETURN 🔥

0 on success, else a negative status code (if no cpus were online). So if nobody’s home CPU-wise, you get a negative status code and not a happy little zero. 💀

🦋 SEE ALSO 🦋

Kernel file ./kernel/smp.c, plus the whole friend group: csd_lock_is_stuck(9), generic_smp_call_function_single_interrupt(9), __flush_smp_call_function_queue(9), flush_smp_call_function_queue(9), smp_call_function_single(9), smp_call_function_single_async(9), smp_call_function_many(9), smp_call_function(9), on_each_cpu_cond_mask(9), kick_all_cpus_sync(9), wake_up_all_idle_cpus(9), cpus_peek_for_pending_ipi(9), struct smp_call_on_cpu_struct(9), smp_call_on_cpu(9). Go read them, iykyk. 👑

xoxo, signed off by the source/version bestie ./kernel, dated October 2026 💖✨🎀