sys_sched_setaffinity(9)

sys_sched_setaffinity(9) 💖✨

okay so bestie, welcome to the Kernel API Manual entry for sys_sched_setaffinity — the one that’s all about setting the CPU affinity of a process. It’s giving “tell this process which CPU it’s allowed to vibe on” energy, and honestly? iconic. 💅

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🌸 NAME 🌸

sys_sched_setaffinity — set the CPU affinity of a process.

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✨ SYNOPSIS ✨

       long sys_sched_setaffinity (pid_t pid , unsigned int len , unsigned long
       __user * user_mask_ptr );

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🎀 ARGUMENTS 🎀

• pid — the pid of the process. literally the process ID, bestie 🫶
• len — length in bytes of the bitmask pointed to by user_mask_ptr. yes, bytes. no cap.
• user_mask_ptr — user-space pointer to the new CPU mask. it’s the pointer bestie, the whole vibe check for the mask 💫

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🌈 RETURN 🌈

0 on success. An error code otherwise. that’s it, that’s the whole return situation 😌

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🦋 SEE ALSO 🦋

Kernel file: ./kernel/sched/syscalls.c

• task_prio(9)
• idle_cpu(9)
• idle_task(9)
• find_process_by_pid(9)
• sched_setscheduler(9)
• sched_setscheduler_nocheck(9)
• sys_sched_setscheduler(9)
• sys_sched_setparam(9)
• sys_sched_setattr(9)
• sys_sched_getscheduler(9)
• sys_sched_getparam(9)
• sys_sched_getattr(9)
• sys_sched_getaffinity(9)
• sys_sched_yield(9)
• yield(9)
• yield_to(9)
• sys_sched_get_priority_max(9)
• sys_sched_get_priority_min(9)
• sys_sched_rr_get_interval(9)

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mwah 💋 this page came from the Kernel API Manual, source/version ./kernel/sched, dated October 2026, and it’s literally the sys_sched_setaffinity(9) page. bye bestie 🫶✨