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>
Extended Key ID allows A-MPDU sessions while rekeying as long as each
A-MPDU aggregates only MPDUs with one keyid together.
Drivers able to segregate MPDUs accordingly can tell mac80211 to not
stop A-MPDU sessions when rekeying by setting the new flag
IEEE80211_HW_AMPDU_KEYBORDER_SUPPORT.
Signed-off-by: Alexander Wetzel <alexander@wetzel-home.de>
Link: https://lore.kernel.org/r/20190629195015.19680-3-alexander@wetzel-home.de
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
1) Drop IEEE80211_HW_EXT_KEY_ID_NATIVE and let drivers directly set
the NL80211_EXT_FEATURE_EXT_KEY_ID flag.
2) Drop IEEE80211_HW_NO_AMPDU_KEYBORDER_SUPPORT and simply assume all
drivers are unable to handle A-MPDU key borders.
The new Extended Key ID API now requires all mac80211 drivers to set
NL80211_EXT_FEATURE_EXT_KEY_ID when they implement set_key() and can
handle Extended Key ID. For drivers not providing set_key() mac80211
itself enables Extended Key ID support, using the internal SW crypto
services.
Signed-off-by: Alexander Wetzel <alexander@wetzel-home.de>
Link: https://lore.kernel.org/r/20190629195015.19680-2-alexander@wetzel-home.de
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
IEEE 802.11 - 2016 forbids mixing MPDUs with different keyIDs in one
A-MPDU. Drivers supporting A-MPDUs and Extended Key ID must actively
enforce that requirement due to the available two unicast keyIDs.
Allow driver to signal mac80211 that they will not check the keyID in
MPDUs when aggregating them and that they expect mac80211 to stop Tx
aggregation when rekeying a connection using Extended Key ID.
Signed-off-by: Alexander Wetzel <alexander@wetzel-home.de>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
At Technical University of Munich we use MAC 802.11 TX status frames to
perform several measurements in MAC 802.11 setups.
With ath based drivers this was possible until commit d94a461d7a
("ath9k: use ieee80211_tx_status_noskb where possible") as the driver
ignored the IEEE80211_TX_CTL_REQ_TX_STATUS flag and always delivered
tx_status frames. Since that commit, this behavior was changed and the
driver now adheres to IEEE80211_TX_CTL_REQ_TX_STATUS.
Due to performance reasons, IEEE80211_TX_CTL_REQ_TX_STATUS is not set for
data frames from interfaces in managed mode. Hence, frames that are sent
from a managed mode interface do never deliver tx_status frames. This
remains true even if a monitor mode interface (the measurement interface)
is added to the same ieee80211 physical device. Thus, there is no
possibility for receiving tx_status frames for frames sent on an interface
in managed mode, if the driver adheres to IEEE80211_TX_CTL_REQ_TX_STATUS.
In order to force delivery of tx_status frames for research and debugging
purposes, implement a debugfs option force_tx_status for ieee80211 physical
devices. When this option is set for a physical device,
IEEE80211_TX_CTL_REQ_TX_STATUS is enabled in all packets sent from that
device. This option can be set via
/sys/kernel/debug/ieee80211/<dev>/force_tx_status. The default is disabled.
Co-developed-by: Charlie Groh <ga58taw@mytum.de>
Signed-off-by: Charlie Groh <ga58taw@mytum.de>
Signed-off-by: Julius Niedworok <julius.n@gmx.net>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Add support for Extended Key ID as defined in IEEE 802.11-2016.
- Implement the nl80211 API for Extended Key ID
- Extend mac80211 API to allow drivers to support Extended Key ID
- Enable Extended Key ID by default for drivers only supporting SW
crypto (e.g. mac80211_hwsim)
- Allow unicast Tx usage to be supressed (IEEE80211_KEY_FLAG_NO_AUTO_TX)
- Select the decryption key based on the MPDU keyid
- Enforce existing assumptions in the code that rekeys don't change the
cipher
Signed-off-by: Alexander Wetzel <alexander@wetzel-home.de>
[remove module parameter]
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Some hardware (e.g. MediaTek MT7603) cannot report A-MPDU length in tx status
information. Add support for a flag to indicate that, to allow minstrel_ht
to use a fixed value in its internal calculation (which gives better results
than just defaulting to 1).
Signed-off-by: Felix Fietkau <nbd@nbd.name>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
This adds airtime accounting and scheduling to the mac80211 TXQ
scheduler. A new callback, ieee80211_sta_register_airtime(), is added
that drivers can call to report airtime usage for stations.
When airtime information is present, mac80211 will schedule TXQs
(through ieee80211_next_txq()) in a way that enforces airtime fairness
between active stations. This scheduling works the same way as the ath9k
in-driver airtime fairness scheduling. If no airtime usage is reported
by the driver, the scheduler will default to round-robin scheduling.
For drivers that don't control TXQ scheduling in software, a new API
function, ieee80211_txq_may_transmit(), is added which the driver can use
to check if the TXQ is eligible for transmission, or should be throttled to
enforce fairness. Calls to this function must also be enclosed in
ieee80211_txq_schedule_{start,end}() calls to ensure proper locking.
The API ieee80211_txq_may_transmit() also ensures that TXQ list will be
aligned aginst driver's own round-robin scheduler list. i.e it rotates
the TXQ list till it makes the requested node becomes the first entry
in TXQ list. Thus both the TXQ list and driver's list are in sync.
Co-developed-by: Rajkumar Manoharan <rmanohar@codeaurora.org>
Signed-off-by: Louie Lu <git@louie.lu>
[added debugfs write op to reset airtime counter]
Signed-off-by: Toke Høiland-Jørgensen <toke@toke.dk>
Signed-off-by: Rajkumar Manoharan <rmanohar@codeaurora.org>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
We have a TXQ abstraction for non-data packets that need
powersave buffering. Since the AP cannot sleep, in case
of station we can use this TXQ for all management frames,
regardless if they are bufferable. Add HW flag to allow
that.
Signed-off-by: Sara Sharon <sara.sharon@intel.com>
Signed-off-by: Luca Coelho <luciano.coelho@intel.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Depending on whether or not rate control supports selecting
rates depending on the bandwidth, we can use VHT extended
NSS support. In essence, this is dot11VHTExtendedNSSBWCapable
from the spec, since depending on that we'll need to parse
the bandwidth.
If needed, also set/clear the VHT Capability Element bit for
this capability so that we don't advertise it erroneously or
don't advertise it when we actually use it.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Some drivers may want to also use the TXQ abstraction with
non-data packets that need powersave buffering, so add a
hardware flag to allow this.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Fun set of conflict resolutions here...
For the mac80211 stuff, these were fortunately just parallel
adds. Trivially resolved.
In drivers/net/phy/phy.c we had a bug fix in 'net' that moved the
function phy_disable_interrupts() earlier in the file, whilst in
'net-next' the phy_error() call from this function was removed.
In net/ipv4/xfrm4_policy.c, David Ahern's changes to remove the
'rt_table_id' member of rtable collided with a bug fix in 'net' that
added a new struct member "rt_mtu_locked" which needs to be copied
over here.
The mlxsw driver conflict consisted of net-next separating
the span code and definitions into separate files, whilst
a 'net' bug fix made some changes to that moved code.
The mlx5 infiniband conflict resolution was quite non-trivial,
the RDMA tree's merge commit was used as a guide here, and
here are their notes:
====================
Due to bug fixes found by the syzkaller bot and taken into the for-rc
branch after development for the 4.17 merge window had already started
being taken into the for-next branch, there were fairly non-trivial
merge issues that would need to be resolved between the for-rc branch
and the for-next branch. This merge resolves those conflicts and
provides a unified base upon which ongoing development for 4.17 can
be based.
Conflicts:
drivers/infiniband/hw/mlx5/main.c - Commit 42cea83f95
(IB/mlx5: Fix cleanup order on unload) added to for-rc and
commit b5ca15ad7e (IB/mlx5: Add proper representors support)
add as part of the devel cycle both needed to modify the
init/de-init functions used by mlx5. To support the new
representors, the new functions added by the cleanup patch
needed to be made non-static, and the init/de-init list
added by the representors patch needed to be modified to
match the init/de-init list changes made by the cleanup
patch.
Updates:
drivers/infiniband/hw/mlx5/mlx5_ib.h - Update function
prototypes added by representors patch to reflect new function
names as changed by cleanup patch
drivers/infiniband/hw/mlx5/ib_rep.c - Update init/de-init
stage list to match new order from cleanup patch
====================
Signed-off-by: David S. Miller <davem@davemloft.net>
Commit 7b6ddeaf27 ("mac80211: use QoS NDP for AP probing") added an
argument qos_ok to ieee80211_nullfunc_get to support QoS NDP. Despite
the claim in the commit log "Change all the drivers to *not* allow
QoS NDP for now, even though it looks like most of them should be OK
with that", this commit enables QoS NDP in response to beacons (see
change to mlme.c:ieee80211_send_nullfunc), causing ath9k_htc to lose
IP connectivity. See:
https://patchwork.kernel.org/patch/10241109/https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=891060
Introduce a hardware flag to allow such buggy drivers to override the
correct default behaviour of mac80211 of sending QoS NDP packets.
Signed-off-by: Ben Caradoc-Davies <ben@transient.nz>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
In multi channel scenarios, when disassociating from the AP before a
beacon was heard from the AP, it is not guaranteed that the virtual
interface is granted air time for the transmission of the
deauthentication frame. This in turn can lead to various issues as
the AP might never get the deauthentication frame.
To mitigate such possible issues, add a HW flag indicating that the
driver requires mac80211 to call the mgd_prep_tx() driver callback
to make sure that the virtual interface is granted immediate airtime
to be able to transmit the frame, in case that no beacon was heard
from the AP.
Signed-off-by: Ilan Peer <ilan.peer@intel.com>
Signed-off-by: Luca Coelho <luciano.coelho@intel.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
This reverts commit b0d52ad821.
We need to revert the TXQ scheduling API due to conflicts
with a new driver, and this depends on that API.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
This adds airtime accounting and scheduling to the mac80211 TXQ
scheduler. A new hardware flag, AIRTIME_ACCOUNTING, is added that
drivers can set if they support reporting airtime usage of
transmissions. When this flag is set, mac80211 will expect the actual
airtime usage to be reported in the tx_time and rx_time fields of the
respective status structs.
When airtime information is present, mac80211 will schedule TXQs
(through ieee80211_next_txq()) in a way that enforces airtime fairness
between active stations. This scheduling works the same way as the ath9k
in-driver airtime fairness scheduling.
Signed-off-by: Toke Høiland-Jørgensen <toke@toke.dk>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Allow drivers to set the buffer station extended capability
for TDLS links, with a new hardware flag indicating this.
Signed-off-by: Yingying Tang <yintang@qti.qualcomm.com>
[change commit log/documentation wording]
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
kmalloc() can fail. Also let's move the allocation out of the
declaration block so it's easier to read.
Fixes: 4a5eccaa93 ("mac80211: Show pending txqlen in debugfs.")
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Somehow these files were never present or lost, but the code
is there and they seem somewhat useful, so add them back.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Could be useful for debugging memory consumption issues,
and perhaps power-save as well.
Signed-off-by: Ben Greear <greearb@candelatech.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
