for_each_pool(9)

💅 for_each_pool(9) — Kernel API Manual ✨

okay bestie, welcome to the Kernel API Manual page for for_each_pool(9) — yes, that’s the title and the manual name all folded in near the top, we are so back. 🫶

🌸 NAME 🌸

for_each_pool - iterate through all worker_pools in the system. periodt. 👑

✨ SYNOPSIS ✨

for_each_pool (pool , pi );

🎀 ARGUMENTS 🎀

• pool — iteration cursor. it’s giving “we are walking through the pools”, bestie. 🚶‍♀️
• pi — integer used for iteration. just an integer doing its little iteration job. 🔢

🦋 DESCRIPTION 🦋

okay so the big rule, no cap: this must be called either with wq_pool_mutex held or RCU read locked. ngl, this is highkey the whole vibe check. 🔒

If the pool needs to be used beyond the locking in effect, the caller is responsible for guaranteeing that the pool stays online. fr fr — if you’re gonna keep using it after the lock situation changes, that’s on you, bestie. keep that pool online. 🫶

The if/else clause exists only for the lockdep assertion and can be ignored. not me lowkey explaining that the if/else is just there for the lockdep assertion — you can literally ignore it. 💅

🌈 SEE ALSO 🌈

Kernel file ./kernel/workqueue.c is main character energy, and the SEE ALSO besties are: for_each_pool_worker(9), for_each_pwq(9), worker_pool_assign_id(9), unbound_effective_cpumask(9), get_work_pool(9), worker_set_flags(9), worker_clr_flags(9), worker_enter_idle(9), worker_leave_idle(9), find_worker_executing_work(9), move_linked_works(9), assign_work(9), kick_pool_pick(9), kick_pool(9), wq_worker_running(9), wq_worker_sleeping(9), wq_worker_tick(9), wq_worker_last_func(9), wq_node_nr_active(9), wq_update_node_max_active(9), get_pwq(9), put_pwq(9), put_pwq_unlocked(9), pwq_tryinc_nr_active(9), pwq_activate_first_inactive(9), unplug_oldest_pwq(9), node_activate_pending_pwq(9), pwq_dec_nr_active(9), pwq_dec_nr_in_flight(9), try_to_grab_pending(9), work_grab_pending(9), insert_work(9), queue_work_on(9), select_numa_node_cpu(9), queue_work_node(9), queue_delayed_work_on(9), mod_delayed_work_on(9), queue_rcu_work(9), worker_attach_to_pool(9), worker_detach_from_pool(9), create_worker(9), set_worker_dying(9), idle_worker_timeout(9), idle_cull_fn(9), maybe_create_worker(9), manage_workers(9), process_one_work(9), process_scheduled_works(9), worker_thread(9), rescuer_thread(9), check_flush_dependency(9), insert_wq_barrier(9), flush_workqueue_prep_pwqs(9), __flush_workqueue(9), drain_workqueue(9), flush_work(9), flush_delayed_work(9), flush_rcu_work(9), cancel_work_sync(9), cancel_delayed_work(9), cancel_delayed_work_sync(9), disable_work(9), disable_work_sync(9), enable_work(9), disable_delayed_work(9), disable_delayed_work_sync(9), enable_delayed_work(9), schedule_on_each_cpu(9), execute_in_process_context(9), free_workqueue_attrs(9), alloc_workqueue_attrs(9), init_worker_pool(9), put_unbound_pool(9), get_unbound_pool(9), wq_calc_pod_cpumask(9), apply_workqueue_attrs(9), unbound_wq_update_pwq(9), wq_adjust_max_active(9), destroy_workqueue(9), workqueue_set_max_active(9), workqueue_set_min_active(9), current_work(9), current_is_workqueue_rescuer(9), current_is_workqueue_mem_reclaim(9), workqueue_congested(9), work_busy(9), set_worker_desc(9), print_worker_info(9), show_one_workqueue(9), show_one_worker_pool(9), show_all_workqueues(9), show_freezable_workqueues(9), rebind_workers(9), restore_unbound_workers_cpumask(9), work_on_cpu_key(9), freeze_workqueues_begin(9), freeze_workqueues_busy(9), thaw_workqueues(9), workqueue_unbound_housekeeping_update(9), workqueue_set_unbound_cpumask(9), workqueue_sysfs_register(9), workqueue_sysfs_unregister(9), workqueue_init_early(9), workqueue_init(9), llc_count_cores(9), llc_populate_cpu_shard_id(9), precompute_cache_shard_ids(9), workqueue_init_topology(9).

iykyk — this list ate, and honestly? obsessed. 💅🔥

💖 okay that’s the whole for_each_pool(9) moment, bestie — source/version ./kernel, date October 2026. this page is iconic, the locking rule is iconic, you are iconic. mwah! 💋✨🎀