css_create(9)

💅 css_create(9) — Kernel API Manual ✨

okay bestie, you already know the manual page name is css_create(9) — the header of this whole thing — and it lives in the Kernel API Manual. let's get into it, no cap 🫶

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✨ NAME ✨

css_create — create a cgroup_subsys_state 🎀

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🌸 SYNOPSIS 🌸

struct cgroup_subsys_state * css_create (struct cgroup *cgrp , struct
cgroup_subsys *ss );

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🦋 ARGUMENTS 🦋

• cgrp — the cgroup that the new css is gonna be associated with, like literally its new home 💖
• ss — the subsys of the new css ✨

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💜 DESCRIPTION 💜

okay so the whole vibe here: css_create creates a brand-new css that's associated with the cgrp - ss pair. iconic pairing, honestly 👑

on success, the new css is online and installed in cgrp — like it's moved in and unpacked its boxes already 🧳✨

heads up though bestie: this function doesn't create the interface files. that's somebody else's job, not ours, periodt 💅

it returns 0 on success, and -errno on failure 😭 so yeah, check your return values, iykyk.

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🌈 SEE ALSO 🌈

kernel file ./kernel/cgroup/cgroup.c — plus the whole friend group, and yes i'm listing every single one because we don't do half measures here 💀

• 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), kill_css_sync(9)
• kill_css_finish(9), cgroup_destroy_locked(9), cgroup_init_early(9), cgroup_init(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)

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and that's the whole page, bestie 🫶✨ this cutie pie of a manpage ships from ./kernel/cgroup 📁, dated October 2026 🗓️, and it's filed under css_create(9) — slay, go forth and create your cgroup_subsys_states responsibly 💅💖🌸