MAC80211 SOFTWARE TX QUEUEING(9)

💅 mac80211 software tx queueing 💅

okay so bestie, you're on the mac80211 so... tx queueing(9) page from the Kernel API Manual, and it is genuinely giving "intermediate queues that keep the hardware from spiraling" ✨. mac80211 uses an intermediate queueing implementation, designed to let the driver keep hardware queues short and to provide some fairness between different stations/interfaces. slay.

Drivers must provide the .wake_tx_queue driver operation — either link it to ieee80211_handle_wake_tx_queue or implement a custom handler. no cap, that part is mandatory 🫶.

The intermediate queues (struct ieee80211_txq) are kept per-sta per-tid, plus another per-sta queue for non-data/non-mgmt and bufferable management frames, plus a single per-vif queue for multicast data frames. the way that's organized? obsessed 🎀.

Drivers are expected to initialize their private per-queue data for stations and interfaces in the .add_interface and .sta_add ops. 💖

The driver can't access the internal TX queues (iTXQs) directly. Whenever mac80211 adds a new frame to a queue, it calls the .wake_tx_queue driver op. Drivers implementing a custom .wake_tx_queue op can get them by calling ieee80211_tx_dequeue. Drivers using ieee80211_handle_wake_tx_queue will simply get the individual frames pushed via the .tx driver operation. iykyk 💅.

Drivers can optionally delegate responsibility for scheduling queues to mac80211, to take advantage of airtime fairness accounting. In this case, to obtain the next queue to pull frames from, the driver calls ieee80211_next_txq. The driver is then expected to return the txq using ieee80211_return_txq. that's the whole loop, bestie 🔁.

For AP powersave TIM handling, the driver only needs to indicate if it has buffered packets in the driver specific data structures by calling ieee80211_sta_set_buffered. For frames buffered in the ieee80211_txq struct, mac80211 sets the appropriate TIM PVB bits and calls .release_buffered_frames. In that callback the driver is therefore expected to release its own buffered frames and afterwards also frames from the ieee80211_txq (obtained via the usual ieee80211_tx_dequeue). periodt 💖.

🌈 SEE ALSO 🌈

bestie, if you wanna fall down the kernel-doc rabbit hole, every single linked page is right here — not a crumb left out 🍓:

• Kernel file ./include/net/mac80211.h; also Introduction(9), Calling mac80211 from interrupts(9), Warning(9), Frame format(9), mac80211 workqueue(9), HW timestamping(9).
• enum ieee80211_max_queues(9), enum ieee80211_ac_numbers(9), struct ieee80211_tx_queue_params(9), enum ieee80211_chanctx_change(9), struct ieee80211_chan_req(9), struct ieee80211_chanctx_conf(9), enum ieee80211_chanctx_switch_mode(9), struct ieee80211_vif_chanctx_switch(9), enum ieee80211_bss_change(9), enum ieee80211_event_type(9).
• enum ieee80211_rssi_event_data(9), struct ieee80211_rssi_event(9), enum ieee80211_mlme_event_data(9), enum ieee80211_mlme_event_status(9), struct ieee80211_mlme_event(9), struct ieee80211_ba_event(9), struct ieee80211_event(9), struct ieee80211_mu_group_data(9), struct ieee80211_ftm_responder_params(9), struct ieee80211_fils_discovery(9).
• struct ieee80211_parsed_tpe(9), struct ieee80211_bss_npca_params(9), struct ieee80211_bss_conf(9), struct ieee80211_nan_channel(9), struct ieee80211_nan_peer_map(9), struct ieee80211_nan_peer_sched(9), enum mac80211_tx_info_flags(9), enum mac80211_tx_control_flags(9), enum mac80211_tx_status_flags(9), enum mac80211_rate_control_flags(9).
• struct ieee80211_tx_rate(9), struct ieee80211_tx_info(9), struct ieee80211_tx_status(9), struct ieee80211_scan_ies(9), ieee80211_tx_info_clear_status(9), enum mac80211_rx_flags(9), enum mac80211_rx_encoding_flags(9), struct ieee80211_rx_status(9), enum ieee80211_conf_flags(9), enum ieee80211_conf_changed(9).
• enum ieee80211_smps_mode(9), struct ieee80211_conf(9), struct ieee80211_channel_switch(9), enum ieee80211_vif_flags(9), enum ieee80211_offload_flags(9), struct ieee80211_eml_params(9), struct ieee80211_nan_sched_cfg(9), struct ieee80211_vif_cfg(9), struct ieee80211_neg_ttlm(9), enum ieee80211_neg_ttlm_res(9).
• struct ieee80211_vif(9), ieee80211_vif_usable_links(9), ieee80211_vif_is_mld(9), ieee80211_vif_link_active(9), wdev_to_ieee80211_vif(9), ieee80211_vif_to_wdev(9), enum ieee80211_key_flags(9), struct ieee80211_key_conf(9), struct ieee80211_key_seq(9), enum set_key_cmd(9).
• enum ieee80211_sta_state(9), enum ieee80211_sta_rx_bandwidth(9), struct ieee80211_sta_rates(9), struct ieee80211_sta_txpwr(9), struct ieee80211_sta_aggregates(9), struct ieee80211_link_sta(9), struct ieee80211_sta(9), enum sta_notify_cmd(9), struct ieee80211_tx_control(9), struct ieee80211_txq(9).
• enum ieee80211_hw_flags(9), struct ieee80211_hw(9), struct ieee80211_scan_request(9), struct ieee80211_tdls_ch_sw_params(9), wiphy_to_ieee80211_hw(9), SET_IEEE80211_DEV(9), SET_IEEE80211_PERM_ADDR(9), ieee80211_free_txskb(9), ieee80211_purge_tx_queue(9), Hardware crypto acceleration(9).
• Powersave support(9), Beacon filter support(9), Spatial multiplexing power save(9), Frame filtering(9), AP support for powersaving clients(9), HW queue control(9), enum ieee80211_filter_flags(9), enum ieee80211_ampdu_mlme_action(9), struct ieee80211_ampdu_params(9), enum ieee80211_frame_release_type(9).
• enum ieee80211_rate_control_changed(9), enum ieee80211_roc_type(9), enum ieee80211_reconfig_type(9), struct ieee80211_prep_tx_info(9), struct ieee80211_ops(9), ieee80211_alloc_hw_nm(9), ieee80211_alloc_hw(9), ieee80211_register_hw(9), struct ieee80211_tpt_blink(9), enum ieee80211_tpt_led_trigger_flags(9).
• ieee80211_get_tx_led_name(9), ieee80211_get_rx_led_name(9), ieee80211_get_assoc_led_name(9), ieee80211_get_radio_led_name(9), ieee80211_create_tpt_led_trigger(9), ieee80211_unregister_hw(9), ieee80211_free_hw(9), ieee80211_restart_hw(9), ieee80211_rx_list(9), ieee80211_rx_napi(9).
• ieee80211_rx(9), ieee80211_rx_irqsafe(9), ieee80211_rx_ni(9), ieee80211_sta_ps_transition(9), ieee80211_sta_ps_transition_ni(9), ieee80211_sta_pspoll(9), ieee80211_sta_uapsd_trigger(9), ieee80211_sta_set_buffered(9), ieee80211_get_tx_rates(9), ieee80211_tx_rate_update(9).
• ieee80211_tx_status_skb(9), ieee80211_tx_status_ext(9), ieee80211_tx_status_noskb(9), ieee80211_tx_status_ni(9), ieee80211_tx_status_irqsafe(9), ieee80211_report_low_ack(9), struct ieee80211_mutable_offsets(9), ieee80211_beacon_get_template(9), ieee80211_beacon_get_template_ema_index(9), struct ieee80211_ema_beacons(9).
• ieee80211_beacon_get_template_ema_list(9), ieee80211_beacon_free_ema_list(9), ieee80211_beacon_get_tim(9), ieee80211_beacon_get(9), ieee80211_beacon_update_cntdwn(9), ieee80211_beacon_set_cntdwn(9), ieee80211_csa_finish(9), ieee80211_beacon_cntdwn_is_complete(9), ieee80211_color_change_finish(9), ieee80211_proberesp_get(9).
• ieee80211_pspoll_get(9), ieee80211_nullfunc_get(9), ieee80211_probereq_get(9), ieee80211_rts_get(9), ieee80211_rts_duration(9), ieee80211_ctstoself_get(9), ieee80211_ctstoself_duration(9), ieee80211_generic_frame_duration(9), ieee80211_get_buffered_bc(9), ieee80211_get_tkip_p1k_iv(9).
• ieee80211_get_tkip_p1k(9), ieee80211_get_tkip_rx_p1k(9), ieee80211_get_tkip_p2k(9), ieee80211_tkip_add_iv(9), ieee80211_get_key_rx_seq(9), ieee80211_set_key_rx_seq(9), ieee80211_gtk_rekey_add(9), ieee80211_gtk_rekey_notify(9), ieee80211_key_mic_failure(9), ieee80211_key_replay(9).
• ieee80211_wake_queue(9), ieee80211_stop_queue(9), ieee80211_queue_stopped(9), ieee80211_stop_queues(9), ieee80211_wake_queues(9), ieee80211_scan_completed(9), ieee80211_sched_scan_results(9), ieee80211_sched_scan_stopped(9), enum ieee80211_interface_iteration_flags(9), ieee80211_iterate_interfaces(9).
• ieee80211_iterate_active_interfaces(9), ieee80211_iterate_active_interfaces_atomic(9), for_each_interface(9), for_each_active_interface(9), ieee80211_iterate_active_interfaces_mtx(9), ieee80211_iterate_stations_atomic(9), for_each_station(9), ieee80211_iterate_stations_mtx(9), ieee80211_queue_work(9), ieee80211_queue_delayed_work(9).
• ieee80211_refresh_tx_agg_session_timer(9), ieee80211_start_tx_ba_session(9), ieee80211_start_tx_ba_cb_irqsafe(9), ieee80211_stop_tx_ba_session(9), ieee80211_stop_tx_ba_cb_irqsafe(9), ieee80211_find_sta(9), ieee80211_find_sta_by_ifaddr(9), ieee80211_find_sta_by_link_addrs(9), ieee80211_sta_block_awake(9), ieee80211_sta_eosp(9).
• ieee80211_send_eosp_nullfunc(9), ieee80211_sta_recalc_aggregates(9), ieee80211_sta_register_airtime(9), ieee80211_txq_airtime_check(9), ieee80211_txq_aql_pending(9), ieee80211_iter_keys(9), ieee80211_iter_keys_rcu(9), ieee80211_iter_chan_contexts_atomic(9), ieee80211_iter_chan_contexts_mtx(9), ieee80211_ap_probereq_get(9).
• ieee80211_beacon_loss(9), ieee80211_connection_loss(9), ieee80211_disconnect(9), ieee80211_resume_disconnect(9), ieee80211_hw_restart_disconnect(9), ieee80211_cqm_rssi_notify(9), ieee80211_cqm_beacon_loss_notify(9), ieee80211_radar_detected(9), ieee80211_chswitch_done(9), ieee80211_channel_switch_disconnect(9).
• ieee80211_request_smps(9), ieee80211_ready_on_channel(9), ieee80211_remain_on_channel_expired(9), ieee80211_stop_rx_ba_session(9), ieee80211_mark_rx_ba_filtered_frames(9), ieee80211_send_bar(9), ieee80211_manage_rx_ba_offl(9), ieee80211_start_rx_ba_session_offl(9), ieee80211_stop_rx_ba_session_offl(9), ieee80211_rx_ba_timer_expired(9).
• struct ieee80211_tx_rate_control(9), enum rate_control_capabilities(9), rate_control_set_rates(9), ieee80211_get_he_iftype_cap_vif(9), ieee80211_get_he_6ghz_capa_vif(9), ieee80211_get_eht_iftype_cap_vif(9), ieee80211_get_uhr_iftype_cap_vif(9), ieee80211_update_mu_groups(9), ieee80211_ave_rssi(9), ieee80211_calculate_rx_timestamp(9).
• ieee80211_report_wowlan_wakeup(9), ieee80211_tx_prepare_skb(9), ieee80211_parse_tx_radiotap(9), struct ieee80211_noa_data(9), ieee80211_parse_p2p_noa(9), ieee80211_update_p2p_noa(9), ieee80211_tdls_oper_request(9), ieee80211_reserve_tid(9), ieee80211_unreserve_tid(9), ieee80211_tx_dequeue(9).
• ieee80211_tx_dequeue_ni(9), ieee80211_handle_wake_tx_queue(9), ieee80211_next_txq(9), ieee80211_txq_schedule_start(9), ieee80211_schedule_txq(9), ieee80211_return_txq(9), ieee80211_txq_may_transmit(9), ieee80211_txq_get_depth(9), ieee80211_nan_func_terminated(9), ieee80211_nan_func_match(9).
• ieee80211_nan_sched_update_done(9), ieee80211_nan_cluster_joined(9), ieee80211_nan_try_evacuate(9), ieee80211_calc_rx_airtime(9), ieee80211_calc_tx_airtime(9), ieee80211_get_fils_discovery_tmpl(9), ieee80211_get_unsol_bcast_probe_resp_tmpl(9), ieee80211_obss_color_collision_notify(9), ieee80211_is_tx_data(9), ieee80211_set_active_links(9).
• ieee80211_set_active_links_async(9), ieee80211_send_teardown_neg_ttlm(9), ieee80211_chan_width_to_rx_bw(9), ieee80211_prepare_rx_omi_bw(9), ieee80211_finalize_rx_omi_bw(9), ieee80211_vif_nan_started(9), ieee80211_encrypt_tx_skb(9).

made with 💖 from source/version ./include/net, dated October 2026 — that's the mac80211 so... tx queueing(9) page in the Kernel API Manual, bestie. go forth and queue responsibly 🫶.