alistair23-linux/net/mac80211
Kan Yan 3ace10f5b5 mac80211: Implement Airtime-based Queue Limit (AQL)
In order for the Fq_CoDel algorithm integrated in mac80211 layer to operate
effectively to control excessive queueing latency, the CoDel algorithm
requires an accurate measure of how long packets stays in the queue, AKA
sojourn time. The sojourn time measured at the mac80211 layer doesn't
include queueing latency in the lower layer (firmware/hardware) and CoDel
expects lower layer to have a short queue. However, most 802.11ac chipsets
offload tasks such TX aggregation to firmware or hardware, thus have a deep
lower layer queue.

Without a mechanism to control the lower layer queue size, packets only
stay in mac80211 layer transiently before being sent to firmware queue.
As a result, the sojourn time measured by CoDel in the mac80211 layer is
almost always lower than the CoDel latency target, hence CoDel does little
to control the latency, even when the lower layer queue causes excessive
latency.

The Byte Queue Limits (BQL) mechanism is commonly used to address the
similar issue with wired network interface. However, this method cannot be
applied directly to the wireless network interface. "Bytes" is not a
suitable measure of queue depth in the wireless network, as the data rate
can vary dramatically from station to station in the same network, from a
few Mbps to over Gbps.

This patch implements an Airtime-based Queue Limit (AQL) to make CoDel work
effectively with wireless drivers that utilized firmware/hardware
offloading. AQL allows each txq to release just enough packets to the lower
layer to form 1-2 large aggregations to keep hardware fully utilized and
retains the rest of the frames in mac80211 layer to be controlled by the
CoDel algorithm.

Signed-off-by: Kan Yan <kyan@google.com>
[ Toke: Keep API to set pending airtime internal, fix nits in commit msg ]
Signed-off-by: Toke Høiland-Jørgensen <toke@redhat.com>
Link: https://lore.kernel.org/r/20191119060610.76681-4-kyan@google.com
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
2019-11-22 13:36:25 +01:00
..
aead_api.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 500 2019-06-19 17:09:55 +02:00
aead_api.h treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 500 2019-06-19 17:09:55 +02:00
aes_ccm.h treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 500 2019-06-19 17:09:55 +02:00
aes_cmac.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 500 2019-06-19 17:09:55 +02:00
aes_cmac.h treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 500 2019-06-19 17:09:55 +02:00
aes_gcm.h treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 500 2019-06-19 17:09:55 +02:00
aes_gmac.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 500 2019-06-19 17:09:55 +02:00
aes_gmac.h treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 500 2019-06-19 17:09:55 +02:00
agg-rx.c mac80211: add missing null return check from call to ieee80211_get_sband 2019-07-31 10:51:17 +02:00
agg-tx.c mac80211: simplify TX aggregation start 2019-10-04 13:58:13 +02:00
airtime.c mac80211: Import airtime calculation code from mt76 2019-11-22 13:36:25 +01:00
cfg.c mac80211: Shrink the size of ack_frame_id to make room for tx_time_est 2019-11-08 10:19:19 +01:00
chan.c treewide: Add SPDX license identifier for missed files 2019-05-21 10:50:45 +02:00
debug.h License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
debugfs.c mac80211: Implement Airtime-based Queue Limit (AQL) 2019-11-22 13:36:25 +01:00
debugfs.h License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
debugfs_key.c Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2019-06-22 08:59:24 -04:00
debugfs_key.h License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
debugfs_netdev.c mac80211: fix txq null pointer dereference 2019-10-01 17:56:19 +02:00
debugfs_netdev.h License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
debugfs_sta.c mac80211: Implement Airtime-based Queue Limit (AQL) 2019-11-22 13:36:25 +01:00
debugfs_sta.h License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
driver-ops.c mac80211: don't warn about CW params when not using them 2019-07-20 21:40:32 +02:00
driver-ops.h mac80211: pass the vif to cancel_remain_on_channel 2019-07-26 13:08:28 +02:00
ethtool.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 432 2019-06-05 17:37:16 +02:00
fils_aead.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 500 2019-06-19 17:09:55 +02:00
fils_aead.h treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 500 2019-06-19 17:09:55 +02:00
he.c mac80211: fix possible NULL pointerderef in obss pd code 2019-08-21 10:58:32 +02:00
ht.c mac80211: add support for the ADDBA extension element 2019-07-29 16:40:22 +02:00
ibss.c mac80211: IBSS: avoid unneeded return value processing 2019-10-04 13:47:12 +02:00
ieee80211_i.h mac80211: Implement Airtime-based Queue Limit (AQL) 2019-11-22 13:36:25 +01:00
iface.c mac80211: allow drivers to set max MTU 2019-09-11 09:33:29 +02:00
Kconfig Merge branch 'linus' of git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6 2019-07-08 20:57:08 -07:00
key.c mac80211: don't check if key is NULL in ieee80211_key_link() 2019-09-11 09:33:28 +02:00
key.h mac80211: clear crypto tx tailroom counter upon keys enable 2019-09-11 09:33:28 +02:00
led.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 500 2019-06-19 17:09:55 +02:00
led.h treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 500 2019-06-19 17:09:55 +02:00
main.c mac80211: Implement Airtime-based Queue Limit (AQL) 2019-11-22 13:36:25 +01:00
Makefile mac80211: Import airtime calculation code from mt76 2019-11-22 13:36:25 +01:00
mesh.c mac80211: implement HE support for mesh 2019-07-26 16:14:12 +02:00
mesh.h mac80211: implement HE support for mesh 2019-07-26 16:14:12 +02:00
mesh_hwmp.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 500 2019-06-19 17:09:55 +02:00
mesh_pathtbl.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 500 2019-06-19 17:09:55 +02:00
mesh_plink.c mac80211: implement HE support for mesh 2019-07-26 16:14:12 +02:00
mesh_ps.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 500 2019-06-19 17:09:55 +02:00
mesh_sync.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 500 2019-06-19 17:09:55 +02:00
michael.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 500 2019-06-19 17:09:55 +02:00
michael.h treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 500 2019-06-19 17:09:55 +02:00
mlme.c mac80211: don't re-parse elems in ieee80211_assoc_success() 2019-11-08 10:18:31 +01:00
ocb.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 500 2019-06-19 17:09:55 +02:00
offchannel.c mac80211: pass the vif to cancel_remain_on_channel 2019-07-26 13:08:28 +02:00
pm.c License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
rate.c Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2019-06-22 08:59:24 -04:00
rate.h mac80211: remove unused and unneeded remove_sta_debugfs callback 2019-07-26 13:21:12 +02:00
rc80211_minstrel.c mac80211: minstrel_ht: rename prob_ewma to prob_avg, use it for the new average 2019-10-11 10:31:45 +02:00
rc80211_minstrel.h mac80211: minstrel_ht: rename prob_ewma to prob_avg, use it for the new average 2019-10-11 10:31:45 +02:00
rc80211_minstrel_debugfs.c mac80211: minstrel_ht: rename prob_ewma to prob_avg, use it for the new average 2019-10-11 10:31:45 +02:00
rc80211_minstrel_ht.c mac80211: minstrel_ht: rename prob_ewma to prob_avg, use it for the new average 2019-10-11 10:31:45 +02:00
rc80211_minstrel_ht.h mac80211: minstrel_ht: rename prob_ewma to prob_avg, use it for the new average 2019-10-11 10:31:45 +02:00
rc80211_minstrel_ht_debugfs.c mac80211: minstrel_ht: rename prob_ewma to prob_avg, use it for the new average 2019-10-11 10:31:45 +02:00
rx.c mac80211: accept deauth frames in IBSS mode 2019-10-07 21:59:48 +02:00
scan.c mac80211: fix scan when operating on DFS channels in ETSI domains 2019-10-07 22:10:50 +02:00
spectmgmt.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 500 2019-06-19 17:09:55 +02:00
sta_info.c mac80211: Implement Airtime-based Queue Limit (AQL) 2019-11-22 13:36:25 +01:00
sta_info.h mac80211: Implement Airtime-based Queue Limit (AQL) 2019-11-22 13:36:25 +01:00
status.c mac80211: consider QoS Null frames for STA_NULLFUNC_ACKED 2019-11-22 13:36:25 +01:00
tdls.c Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2019-06-17 15:55:34 -07:00
tkip.c Merge branch 'linus' of git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6 2019-07-08 20:57:08 -07:00
tkip.h Merge branch 'linus' of git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6 2019-07-08 20:57:08 -07:00
trace.c License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
trace.h mac80211: pass the vif to cancel_remain_on_channel 2019-07-26 13:08:28 +02:00
trace_msg.h mac80211: Increase MAX_MSG_LEN 2019-03-29 11:20:36 +01:00
tx.c mac80211: Implement Airtime-based Queue Limit (AQL) 2019-11-22 13:36:25 +01:00
util.c mac80211: keep BHs disabled while calling drv_tx_wake_queue() 2019-10-01 17:56:19 +02:00
vht.c mac80211: vht: add support VHT EXT NSS BW in parsing VHT 2019-09-11 09:13:03 +02:00
wep.c Merge branch 'linus' of git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6 2019-07-08 20:57:08 -07:00
wep.h Merge branch 'linus' of git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6 2019-07-08 20:57:08 -07:00
wme.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 500 2019-06-19 17:09:55 +02:00
wme.h treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 500 2019-06-19 17:09:55 +02:00
wpa.c mac80211: add IEEE80211_KEY_FLAG_GENERATE_MMIE to ieee80211_key_flags 2019-07-26 16:14:12 +02:00
wpa.h treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 500 2019-06-19 17:09:55 +02:00