cgroup_init(9)

👑 cgroup_init(9) — the Kernel API Manual, bestie edition

okay so first things first: this page lives in the Kernel API Manual (cgroup_init(9) if you're keeping track), and it's genuinely one of the most "main character energy" functions in the whole cgroup ✨saga✨. Let's get into it 🫶

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💖 NAME

cgroup_init — cgroup initialization. That's the vibe. That's the whole vibe. 🎀

✨ SYNOPSIS

int cgroup_init (void );

like, she takes nothing and she returns an int. lowkey iconic 💅

🦋 ARGUMENTS

• void — no arguments. zero. nada. she doesn't need your input, she's booked and busy 💀

🌸 DESCRIPTION

okay so here's the tea, bestie: cgroup_init registers the cgroup filesystem and the /proc file, and then it initializes any subsystems that didn't request early init.

that's it. that's the whole function. but like… it's the setup function, so if she doesn't slay, nothing else slays. no cap. 🔥

fr fr, everyone else in the cgroup world is downstream of this. she's the opening act AND the stage crew. respect her. 👑

🌈 SEE ALSO

the kernel file to go read with your own two eyes is ./kernel/cgroup/cgroup.c — and then, because this manpage is an overachiever, here's the entire extended friend group 💜:

cgroup_ssid_enabled(9), cgroup_on_dfl(9), cgroup_e_css_by_mask(9), cgroup_e_css(9), cgroup_get_e_css(9), __cgroup_task_count(9), cgroup_task_count(9), for_each_css(9), do_each_subsys_mask(9), css_set_populated(9), css_update_populated(9), css_set_update_populated(9), css_set_move_task(9), compare_css_sets(9), find_existing_css_set(9), allocate_cgrp_cset_links(9), link_css_set(9), find_css_set(9), cgroup_file_mode(9), cgroup_calc_subtree_ss_mask(9), cgroup_kn_unlock(9), cgroup_kn_lock_live(9), css_clear_dir(9), css_populate_dir(9)

cgroup_attach_lock(9), cgroup_attach_unlock(9), cgroup_migrate_add_task(9), cgroup_taskset_first(9), cgroup_taskset_next(9), cgroup_migrate_execute(9), cgroup_migrate_vet_dst(9), cgroup_migrate_finish(9), cgroup_migrate_add_src(9), cgroup_migrate_prepare_dst(9), cgroup_migrate(9), cgroup_attach_task(9), cgroup_update_dfl_csses(9), cgroup_lock_and_drain_offline(9), cgroup_save_control(9), cgroup_propagate_control(9), cgroup_restore_control(9), cgroup_apply_control_enable(9), cgroup_apply_control_disable(9), cgroup_apply_control(9), cgroup_finalize_control(9)

cgroup_enable_threaded(9), cgroup_tryget_css(9), cgroup_addrm_files(9), cgroup_rm_cftypes(9), cgroup_add_cftypes(9), cgroup_add_dfl_cftypes(9), cgroup_add_legacy_cftypes(9), cgroup_file_notify(9), cgroup_file_show(9), css_next_child(9), css_next_descendant_pre(9), css_rightmost_descendant(9), css_next_descendant_post(9), css_has_online_children(9), css_task_iter_advance_css_set(9), css_task_iter_start(9), css_task_iter_next(9), css_task_iter_end(9)

css_create(9), kill_css_sync(9), kill_css_finish(9), cgroup_destroy_locked(9), cgroup_init_early(9), cgroup_fork(9), cgroup_v1v2_get_from_file(9), cgroup_get_from_file(9), cgroup_css_set_fork(9), cgroup_css_set_put_fork(9), cgroup_can_fork(9), cgroup_cancel_fork(9), cgroup_post_fork(9), cgroup_task_exit(9), css_tryget_online_from_dir(9), css_from_id(9), cgroup_get_from_path(9)

cgroup_v1v2_get_from_fd(9), cgroup_get_from_fd(9), cgroup_parse_float(9)

like… that's the whole group chat and honestly? every single one of them ate. go read them, iykyk 🧚

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and that's the page, bestie 🍓 this little gem comes from the source/version tag ./kernel/cgroup, dated October 2026 — so screenshot it, cite it, put it on your fridge, whatever, just don't lose the receipt 💖✨