<feed xmlns='http://www.w3.org/2005/Atom'>
<title>linux-toradex.git/net/mac80211/sta_info.c, branch v5.19</title>
<subtitle>Linux kernel for Apalis and Colibri modules</subtitle>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/'/>
<entry>
<title>mac80211: prepare sta handling for MLO support</title>
<updated>2022-04-11T14:42:03+00:00</updated>
<author>
<name>Sriram R</name>
<email>quic_srirrama@quicinc.com</email>
</author>
<published>2022-04-04T15:41:23+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=046d2e7c50e3087a32a85fd384c21f896dbccf83'/>
<id>046d2e7c50e3087a32a85fd384c21f896dbccf83</id>
<content type='text'>
Currently in mac80211 each STA object is represented
using sta_info datastructure with the associated
STA specific information and drivers access ieee80211_sta
part of it.

With MLO (Multi Link Operation) support being added
in 802.11be standard, though the association is logically
with a single Multi Link capable STA, at the physical level
communication can happen via different advertised
links (uniquely identified by Channel, operating class,
BSSID) and hence the need to handle multiple link
STA parameters within a composite sta_info object
called the MLD STA. The different link STA part of
MLD STA are identified using the link address which can
be same or different as the MLD STA address and unique
link id based on the link vif.

To support extension of such a model, the sta_info
datastructure is modified to hold multiple link STA
objects with link specific params currently within
sta_info moved to this new structure. Similarly this is
done for ieee80211_sta as well which will be accessed
within mac80211 as well as by drivers, hence trivial
driver changes are expected to support this.

For current non MLO supported drivers, only one link STA
is present and link information is accessed via 'deflink'
member.

For MLO drivers, we still need to define the APIs etc. to
get the correct link ID and access the correct part of
the station info.

Currently in mac80211, all link STA info are accessed directly
via deflink. These will be updated to access via link pointers
indexed by link id with MLO support patches, with link id
being 0 for non MLO supported cases.

Except for couple of macro related changes, below spatch takes
care of updating mac80211 and driver code to access to the
link STA info via deflink.

  @ieee80211_sta@
  struct ieee80211_sta *s;
  struct sta_info *si;
  identifier var = {supp_rates, ht_cap, vht_cap, he_cap, he_6ghz_capa, eht_cap, rx_nss, bandwidth, txpwr};
  @@

  (
    s-&gt;
  -    var
  +    deflink.var
  |
   si-&gt;sta.
  -    var
  +    deflink.var
  )

  @sta_info@
  struct sta_info *si;
  identifier var = {gtk, pcpu_rx_stats, rx_stats, rx_stats_avg, status_stats, tx_stats, cur_max_bandwidth};
  @@

  (
    si-&gt;
  -    var
  +    deflink.var
  )

Signed-off-by: Sriram R &lt;quic_srirrama@quicinc.com&gt;
Link: https://lore.kernel.org/r/1649086883-13246-1-git-send-email-quic_srirrama@quicinc.com
[remove MLO-drivers notes from commit message, not clear yet; run spatch]
Signed-off-by: Johannes Berg &lt;johannes.berg@intel.com&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Currently in mac80211 each STA object is represented
using sta_info datastructure with the associated
STA specific information and drivers access ieee80211_sta
part of it.

With MLO (Multi Link Operation) support being added
in 802.11be standard, though the association is logically
with a single Multi Link capable STA, at the physical level
communication can happen via different advertised
links (uniquely identified by Channel, operating class,
BSSID) and hence the need to handle multiple link
STA parameters within a composite sta_info object
called the MLD STA. The different link STA part of
MLD STA are identified using the link address which can
be same or different as the MLD STA address and unique
link id based on the link vif.

To support extension of such a model, the sta_info
datastructure is modified to hold multiple link STA
objects with link specific params currently within
sta_info moved to this new structure. Similarly this is
done for ieee80211_sta as well which will be accessed
within mac80211 as well as by drivers, hence trivial
driver changes are expected to support this.

For current non MLO supported drivers, only one link STA
is present and link information is accessed via 'deflink'
member.

For MLO drivers, we still need to define the APIs etc. to
get the correct link ID and access the correct part of
the station info.

Currently in mac80211, all link STA info are accessed directly
via deflink. These will be updated to access via link pointers
indexed by link id with MLO support patches, with link id
being 0 for non MLO supported cases.

Except for couple of macro related changes, below spatch takes
care of updating mac80211 and driver code to access to the
link STA info via deflink.

  @ieee80211_sta@
  struct ieee80211_sta *s;
  struct sta_info *si;
  identifier var = {supp_rates, ht_cap, vht_cap, he_cap, he_6ghz_capa, eht_cap, rx_nss, bandwidth, txpwr};
  @@

  (
    s-&gt;
  -    var
  +    deflink.var
  |
   si-&gt;sta.
  -    var
  +    deflink.var
  )

  @sta_info@
  struct sta_info *si;
  identifier var = {gtk, pcpu_rx_stats, rx_stats, rx_stats_avg, status_stats, tx_stats, cur_max_bandwidth};
  @@

  (
    si-&gt;
  -    var
  +    deflink.var
  )

Signed-off-by: Sriram R &lt;quic_srirrama@quicinc.com&gt;
Link: https://lore.kernel.org/r/1649086883-13246-1-git-send-email-quic_srirrama@quicinc.com
[remove MLO-drivers notes from commit message, not clear yet; run spatch]
Signed-off-by: Johannes Berg &lt;johannes.berg@intel.com&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>mac80211: remove useless ieee80211_vif_is_mesh() check</title>
<updated>2022-02-04T15:27:07+00:00</updated>
<author>
<name>Baligh Gasmi</name>
<email>gasmibal@gmail.com</email>
</author>
<published>2022-02-03T15:30:34+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=45d33746d2f2dd45d9b471e4d1ccb27e337fd2e8'/>
<id>45d33746d2f2dd45d9b471e4d1ccb27e337fd2e8</id>
<content type='text'>
We check ieee80211_vif_is_mesh() at the top if() block,
there's no need to check for it again.

Signed-off-by: Baligh Gasmi &lt;gasmibal@gmail.com&gt;
Link: https://lore.kernel.org/r/20220203153035.198697-1-gasmibal@gmail.com
Signed-off-by: Johannes Berg &lt;johannes.berg@intel.com&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
We check ieee80211_vif_is_mesh() at the top if() block,
there's no need to check for it again.

Signed-off-by: Baligh Gasmi &lt;gasmibal@gmail.com&gt;
Link: https://lore.kernel.org/r/20220203153035.198697-1-gasmibal@gmail.com
Signed-off-by: Johannes Berg &lt;johannes.berg@intel.com&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>mac80211: update channel context before station state</title>
<updated>2021-12-14T10:21:39+00:00</updated>
<author>
<name>Mordechay Goodstein</name>
<email>mordechay.goodstein@intel.com</email>
</author>
<published>2021-11-29T13:32:42+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=4dde3c3627b52ca515a34f6f4de3898224aa1dd3'/>
<id>4dde3c3627b52ca515a34f6f4de3898224aa1dd3</id>
<content type='text'>
Currently channel context is updated only after station got an update about
new assoc state, this results in station using the old channel context.

Fix this by moving the update channel context before updating station,
enabling the driver to immediately use the updated channel context in
the new assoc state.

Signed-off-by: Mordechay Goodstein &lt;mordechay.goodstein@intel.com&gt;
Signed-off-by: Luca Coelho &lt;luciano.coelho@intel.com&gt;
Link: https://lore.kernel.org/r/iwlwifi.20211129152938.1c80c17ffd8a.I94ae31378b363c1182cfdca46c4b7e7165cff984@changeid
Signed-off-by: Johannes Berg &lt;johannes.berg@intel.com&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Currently channel context is updated only after station got an update about
new assoc state, this results in station using the old channel context.

Fix this by moving the update channel context before updating station,
enabling the driver to immediately use the updated channel context in
the new assoc state.

Signed-off-by: Mordechay Goodstein &lt;mordechay.goodstein@intel.com&gt;
Signed-off-by: Luca Coelho &lt;luciano.coelho@intel.com&gt;
Link: https://lore.kernel.org/r/iwlwifi.20211129152938.1c80c17ffd8a.I94ae31378b363c1182cfdca46c4b7e7165cff984@changeid
Signed-off-by: Johannes Berg &lt;johannes.berg@intel.com&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>mac80211: fix a memory leak where sta_info is not freed</title>
<updated>2021-11-26T10:39:16+00:00</updated>
<author>
<name>Ahmed Zaki</name>
<email>anzaki@gmail.com</email>
</author>
<published>2021-10-02T14:53:29+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=8f9dcc29566626f683843ccac6113a12208315ca'/>
<id>8f9dcc29566626f683843ccac6113a12208315ca</id>
<content type='text'>
The following is from a system that went OOM due to a memory leak:

wlan0: Allocated STA 74:83:c2:64:0b:87
wlan0: Allocated STA 74:83:c2:64:0b:87
wlan0: IBSS finish 74:83:c2:64:0b:87 (---from ieee80211_ibss_add_sta)
wlan0: Adding new IBSS station 74:83:c2:64:0b:87
wlan0: moving STA 74:83:c2:64:0b:87 to state 2
wlan0: moving STA 74:83:c2:64:0b:87 to state 3
wlan0: Inserted STA 74:83:c2:64:0b:87
wlan0: IBSS finish 74:83:c2:64:0b:87 (---from ieee80211_ibss_work)
wlan0: Adding new IBSS station 74:83:c2:64:0b:87
wlan0: moving STA 74:83:c2:64:0b:87 to state 2
wlan0: moving STA 74:83:c2:64:0b:87 to state 3
.
.
wlan0: expiring inactive not authorized STA 74:83:c2:64:0b:87
wlan0: moving STA 74:83:c2:64:0b:87 to state 2
wlan0: moving STA 74:83:c2:64:0b:87 to state 1
wlan0: Removed STA 74:83:c2:64:0b:87
wlan0: Destroyed STA 74:83:c2:64:0b:87

The ieee80211_ibss_finish_sta() is called twice on the same STA from 2
different locations. On the second attempt, the allocated STA is not
destroyed creating a kernel memory leak.

This is happening because sta_info_insert_finish() does not call
sta_info_free() the second time when the STA already exists (returns
-EEXIST). Note that the caller sta_info_insert_rcu() assumes STA is
destroyed upon errors.

Same fix is applied to -ENOMEM.

Signed-off-by: Ahmed Zaki &lt;anzaki@gmail.com&gt;
Link: https://lore.kernel.org/r/20211002145329.3125293-1-anzaki@gmail.com
[change the error path label to use the existing code]
Signed-off-by: Johannes Berg &lt;johannes.berg@intel.com&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
The following is from a system that went OOM due to a memory leak:

wlan0: Allocated STA 74:83:c2:64:0b:87
wlan0: Allocated STA 74:83:c2:64:0b:87
wlan0: IBSS finish 74:83:c2:64:0b:87 (---from ieee80211_ibss_add_sta)
wlan0: Adding new IBSS station 74:83:c2:64:0b:87
wlan0: moving STA 74:83:c2:64:0b:87 to state 2
wlan0: moving STA 74:83:c2:64:0b:87 to state 3
wlan0: Inserted STA 74:83:c2:64:0b:87
wlan0: IBSS finish 74:83:c2:64:0b:87 (---from ieee80211_ibss_work)
wlan0: Adding new IBSS station 74:83:c2:64:0b:87
wlan0: moving STA 74:83:c2:64:0b:87 to state 2
wlan0: moving STA 74:83:c2:64:0b:87 to state 3
.
.
wlan0: expiring inactive not authorized STA 74:83:c2:64:0b:87
wlan0: moving STA 74:83:c2:64:0b:87 to state 2
wlan0: moving STA 74:83:c2:64:0b:87 to state 1
wlan0: Removed STA 74:83:c2:64:0b:87
wlan0: Destroyed STA 74:83:c2:64:0b:87

The ieee80211_ibss_finish_sta() is called twice on the same STA from 2
different locations. On the second attempt, the allocated STA is not
destroyed creating a kernel memory leak.

This is happening because sta_info_insert_finish() does not call
sta_info_free() the second time when the STA already exists (returns
-EEXIST). Note that the caller sta_info_insert_rcu() assumes STA is
destroyed upon errors.

Same fix is applied to -ENOMEM.

Signed-off-by: Ahmed Zaki &lt;anzaki@gmail.com&gt;
Link: https://lore.kernel.org/r/20211002145329.3125293-1-anzaki@gmail.com
[change the error path label to use the existing code]
Signed-off-by: Johannes Berg &lt;johannes.berg@intel.com&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>Merge tag 'mac80211-next-for-net-next-2021-10-21' of git://git.kernel.org/pub/scm/linux/kernel/git/jberg/mac80211-next</title>
<updated>2021-10-22T17:20:56+00:00</updated>
<author>
<name>Jakub Kicinski</name>
<email>kuba@kernel.org</email>
</author>
<published>2021-10-22T17:20:54+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=24f7cf9b851ee9c395225481308af4ab5065e20a'/>
<id>24f7cf9b851ee9c395225481308af4ab5065e20a</id>
<content type='text'>
Johannes Berg says:

====================
Quite a few changes:
 * the applicable eth_hw_addr_set() and const hw_addr changes
 * various code cleanups/refactorings
 * stack usage reductions across the wireless stack
 * some unstructured find_ie() -&gt; structured find_element()
   changes
 * a few more pieces of multi-BSSID support
 * some 6 GHz regulatory support
 * 6 GHz support in hwsim, for testing userspace code
 * Light Communications (LC, 802.11bb) early band definitions
   to be able to add a first driver soon

* tag 'mac80211-next-for-net-next-2021-10-21' of git://git.kernel.org/pub/scm/linux/kernel/git/jberg/mac80211-next: (35 commits)
  cfg80211: fix kernel-doc for MBSSID EMA
  mac80211: Prevent AP probing during suspend
  nl80211: Add LC placeholder band definition to nl80211_band
  ...
====================

Link: https://lore.kernel.org/r/20211021154953.134849-1-johannes@sipsolutions.net
Signed-off-by: Jakub Kicinski &lt;kuba@kernel.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Johannes Berg says:

====================
Quite a few changes:
 * the applicable eth_hw_addr_set() and const hw_addr changes
 * various code cleanups/refactorings
 * stack usage reductions across the wireless stack
 * some unstructured find_ie() -&gt; structured find_element()
   changes
 * a few more pieces of multi-BSSID support
 * some 6 GHz regulatory support
 * 6 GHz support in hwsim, for testing userspace code
 * Light Communications (LC, 802.11bb) early band definitions
   to be able to add a first driver soon

* tag 'mac80211-next-for-net-next-2021-10-21' of git://git.kernel.org/pub/scm/linux/kernel/git/jberg/mac80211-next: (35 commits)
  cfg80211: fix kernel-doc for MBSSID EMA
  mac80211: Prevent AP probing during suspend
  nl80211: Add LC placeholder band definition to nl80211_band
  ...
====================

Link: https://lore.kernel.org/r/20211021154953.134849-1-johannes@sipsolutions.net
Signed-off-by: Jakub Kicinski &lt;kuba@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>nl80211: Add LC placeholder band definition to nl80211_band</title>
<updated>2021-10-21T15:25:17+00:00</updated>
<author>
<name>Srinivasan Raju</name>
<email>srini.raju@purelifi.com</email>
</author>
<published>2021-10-18T10:00:54+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=63fa04266629b9559d66c4dc18b03e0f9fc04a02'/>
<id>63fa04266629b9559d66c4dc18b03e0f9fc04a02</id>
<content type='text'>
Define LC band which is a draft under IEEE 802.11bb.
Current NL80211_BAND_LC is a placeholder band and
will be more defined IEEE 802.11bb progresses.

Signed-off-by: Srinivasan Raju &lt;srini.raju@purelifi.com&gt;
Link: https://lore.kernel.org/r/20211018100143.7565-2-srini.raju@purelifi.com
Signed-off-by: Johannes Berg &lt;johannes.berg@intel.com&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Define LC band which is a draft under IEEE 802.11bb.
Current NL80211_BAND_LC is a placeholder band and
will be more defined IEEE 802.11bb progresses.

Signed-off-by: Srinivasan Raju &lt;srini.raju@purelifi.com&gt;
Link: https://lore.kernel.org/r/20211018100143.7565-2-srini.raju@purelifi.com
Signed-off-by: Johannes Berg &lt;johannes.berg@intel.com&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>fq_codel: generalise ce_threshold marking for subset of traffic</title>
<updated>2021-10-20T22:24:36+00:00</updated>
<author>
<name>Toke Høiland-Jørgensen</name>
<email>toke@redhat.com</email>
</author>
<published>2021-10-19T17:47:09+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=dfcb63ce1de6b10ba98dee928f9463f37e5a5512'/>
<id>dfcb63ce1de6b10ba98dee928f9463f37e5a5512</id>
<content type='text'>
Commit e72aeb9ee0e3 ("fq_codel: implement L4S style ce_threshold_ect1
marking") expanded the ce_threshold feature of FQ-CoDel so it can
be applied to a subset of the traffic, using the ECT(1) bit of the ECN
field as the classifier. However, hard-coding ECT(1) as the only
classifier for this feature seems limiting, so let's expand it to be more
general.

To this end, change the parameter from a ce_threshold_ect1 boolean, to a
one-byte selector/mask pair (ce_threshold_{selector,mask}) which is applied
to the whole diffserv/ECN field in the IP header. This makes it possible to
classify packets by any value in either the ECN field or the diffserv
field. In particular, setting a selector of INET_ECN_ECT_1 and a mask of
INET_ECN_MASK corresponds to the functionality before this patch, and a
mask of ~INET_ECN_MASK allows using the selector as a straight-forward
match against a diffserv code point:

 # apply ce_threshold to ECT(1) traffic
 tc qdisc replace dev eth0 root fq_codel ce_threshold 1ms ce_threshold_selector 0x1/0x3

 # apply ce_threshold to ECN-capable traffic marked as diffserv AF22
 tc qdisc replace dev eth0 root fq_codel ce_threshold 1ms ce_threshold_selector 0x50/0xfc

Regardless of the selector chosen, the normal rules for ECN-marking of
packets still apply, i.e., the flow must still declare itself ECN-capable
by setting one of the bits in the ECN field to get marked at all.

v2:
- Add tc usage examples to patch description

Signed-off-by: Toke Høiland-Jørgensen &lt;toke@redhat.com&gt;
Reviewed-by: Eric Dumazet &lt;edumazet@google.com&gt;
Link: https://lore.kernel.org/r/20211019174709.69081-1-toke@redhat.com
Signed-off-by: Jakub Kicinski &lt;kuba@kernel.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Commit e72aeb9ee0e3 ("fq_codel: implement L4S style ce_threshold_ect1
marking") expanded the ce_threshold feature of FQ-CoDel so it can
be applied to a subset of the traffic, using the ECT(1) bit of the ECN
field as the classifier. However, hard-coding ECT(1) as the only
classifier for this feature seems limiting, so let's expand it to be more
general.

To this end, change the parameter from a ce_threshold_ect1 boolean, to a
one-byte selector/mask pair (ce_threshold_{selector,mask}) which is applied
to the whole diffserv/ECN field in the IP header. This makes it possible to
classify packets by any value in either the ECN field or the diffserv
field. In particular, setting a selector of INET_ECN_ECT_1 and a mask of
INET_ECN_MASK corresponds to the functionality before this patch, and a
mask of ~INET_ECN_MASK allows using the selector as a straight-forward
match against a diffserv code point:

 # apply ce_threshold to ECT(1) traffic
 tc qdisc replace dev eth0 root fq_codel ce_threshold 1ms ce_threshold_selector 0x1/0x3

 # apply ce_threshold to ECN-capable traffic marked as diffserv AF22
 tc qdisc replace dev eth0 root fq_codel ce_threshold 1ms ce_threshold_selector 0x50/0xfc

Regardless of the selector chosen, the normal rules for ECN-marking of
packets still apply, i.e., the flow must still declare itself ECN-capable
by setting one of the bits in the ECN field to get marked at all.

v2:
- Add tc usage examples to patch description

Signed-off-by: Toke Høiland-Jørgensen &lt;toke@redhat.com&gt;
Reviewed-by: Eric Dumazet &lt;edumazet@google.com&gt;
Link: https://lore.kernel.org/r/20211019174709.69081-1-toke@redhat.com
Signed-off-by: Jakub Kicinski &lt;kuba@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>fq_codel: implement L4S style ce_threshold_ect1 marking</title>
<updated>2021-10-15T10:33:08+00:00</updated>
<author>
<name>Eric Dumazet</name>
<email>edumazet@google.com</email>
</author>
<published>2021-10-14T17:59:18+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=e72aeb9ee0e34c57dc90793d0bf82cab9624d64e'/>
<id>e72aeb9ee0e34c57dc90793d0bf82cab9624d64e</id>
<content type='text'>
Add TCA_FQ_CODEL_CE_THRESHOLD_ECT1 boolean option to select Low Latency,
Low Loss, Scalable Throughput (L4S) style marking, along with ce_threshold.

If enabled, only packets with ECT(1) can be transformed to CE
if their sojourn time is above the ce_threshold.

Note that this new option does not change rules for codel law.
In particular, if TCA_FQ_CODEL_ECN is left enabled (this is
the default when fq_codel qdisc is created), ECT(0) packets can
still get CE if codel law (as governed by limit/target) decides so.

Section 4.3.b of current draft [1] states:

b.  A scheduler with per-flow queues such as FQ-CoDel or FQ-PIE can
    be used for L4S.  For instance within each queue of an FQ-CoDel
    system, as well as a CoDel AQM, there is typically also ECN
    marking at an immediate (unsmoothed) shallow threshold to support
    use in data centres (see Sec.5.2.7 of [RFC8290]).  This can be
    modified so that the shallow threshold is solely applied to
    ECT(1) packets.  Then if there is a flow of non-ECN or ECT(0)
    packets in the per-flow-queue, the Classic AQM (e.g.  CoDel) is
    applied; while if there is a flow of ECT(1) packets in the queue,
    the shallower (typically sub-millisecond) threshold is applied.

Tested:

tc qd replace dev eth1 root fq_codel ce_threshold_ect1 50usec

netperf ... -t TCP_STREAM -- K dctcp

tc -s -d qd sh dev eth1
qdisc fq_codel 8022: root refcnt 32 limit 10240p flows 1024 quantum 9212 target 5ms ce_threshold_ect1 49us interval 100ms memory_limit 32Mb ecn drop_batch 64
 Sent 14388596616 bytes 9543449 pkt (dropped 0, overlimits 0 requeues 152013)
 backlog 0b 0p requeues 152013
  maxpacket 68130 drop_overlimit 0 new_flow_count 95678 ecn_mark 0 ce_mark 7639
  new_flows_len 0 old_flows_len 0

[1] L4S current draft:
https://datatracker.ietf.org/doc/html/draft-ietf-tsvwg-l4s-arch

Signed-off-by: Eric Dumazet &lt;edumazet@google.com&gt;
Cc: Neal Cardwell &lt;ncardwell@google.com&gt;
Cc: Ingemar Johansson S &lt;ingemar.s.johansson@ericsson.com&gt;
Cc: Tom Henderson &lt;tomh@tomh.org&gt;
Cc: Bob Briscoe &lt;in@bobbriscoe.net&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
Add TCA_FQ_CODEL_CE_THRESHOLD_ECT1 boolean option to select Low Latency,
Low Loss, Scalable Throughput (L4S) style marking, along with ce_threshold.

If enabled, only packets with ECT(1) can be transformed to CE
if their sojourn time is above the ce_threshold.

Note that this new option does not change rules for codel law.
In particular, if TCA_FQ_CODEL_ECN is left enabled (this is
the default when fq_codel qdisc is created), ECT(0) packets can
still get CE if codel law (as governed by limit/target) decides so.

Section 4.3.b of current draft [1] states:

b.  A scheduler with per-flow queues such as FQ-CoDel or FQ-PIE can
    be used for L4S.  For instance within each queue of an FQ-CoDel
    system, as well as a CoDel AQM, there is typically also ECN
    marking at an immediate (unsmoothed) shallow threshold to support
    use in data centres (see Sec.5.2.7 of [RFC8290]).  This can be
    modified so that the shallow threshold is solely applied to
    ECT(1) packets.  Then if there is a flow of non-ECN or ECT(0)
    packets in the per-flow-queue, the Classic AQM (e.g.  CoDel) is
    applied; while if there is a flow of ECT(1) packets in the queue,
    the shallower (typically sub-millisecond) threshold is applied.

Tested:

tc qd replace dev eth1 root fq_codel ce_threshold_ect1 50usec

netperf ... -t TCP_STREAM -- K dctcp

tc -s -d qd sh dev eth1
qdisc fq_codel 8022: root refcnt 32 limit 10240p flows 1024 quantum 9212 target 5ms ce_threshold_ect1 49us interval 100ms memory_limit 32Mb ecn drop_batch 64
 Sent 14388596616 bytes 9543449 pkt (dropped 0, overlimits 0 requeues 152013)
 backlog 0b 0p requeues 152013
  maxpacket 68130 drop_overlimit 0 new_flow_count 95678 ecn_mark 0 ce_mark 7639
  new_flows_len 0 old_flows_len 0

[1] L4S current draft:
https://datatracker.ietf.org/doc/html/draft-ietf-tsvwg-l4s-arch

Signed-off-by: Eric Dumazet &lt;edumazet@google.com&gt;
Cc: Neal Cardwell &lt;ncardwell@google.com&gt;
Cc: Ingemar Johansson S &lt;ingemar.s.johansson@ericsson.com&gt;
Cc: Tom Henderson &lt;tomh@tomh.org&gt;
Cc: Bob Briscoe &lt;in@bobbriscoe.net&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>mac80211: Reject zero MAC address in sta_info_insert_check()</title>
<updated>2021-08-13T07:50:43+00:00</updated>
<author>
<name>YueHaibing</name>
<email>yuehaibing@huawei.com</email>
</author>
<published>2021-06-26T13:03:34+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=deebea0ae3f7c1f812ff6b3581dc51445e1be942'/>
<id>deebea0ae3f7c1f812ff6b3581dc51445e1be942</id>
<content type='text'>
As commit 52dba8d7d5ab ("mac80211: reject zero MAC address in add station")
said, we don't consider all-zeroes to be a valid MAC address in most places,
so also reject it here.

Signed-off-by: YueHaibing &lt;yuehaibing@huawei.com&gt;
Link: https://lore.kernel.org/r/20210626130334.13624-1-yuehaibing@huawei.com
Signed-off-by: Johannes Berg &lt;johannes.berg@intel.com&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
As commit 52dba8d7d5ab ("mac80211: reject zero MAC address in add station")
said, we don't consider all-zeroes to be a valid MAC address in most places,
so also reject it here.

Signed-off-by: YueHaibing &lt;yuehaibing@huawei.com&gt;
Link: https://lore.kernel.org/r/20210626130334.13624-1-yuehaibing@huawei.com
Signed-off-by: Johannes Berg &lt;johannes.berg@intel.com&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>mac80211: Switch to a virtual time-based airtime scheduler</title>
<updated>2021-06-23T16:12:00+00:00</updated>
<author>
<name>Toke Høiland-Jørgensen</name>
<email>toke@redhat.com</email>
</author>
<published>2021-06-23T13:47:55+00:00</published>
<link rel='alternate' type='text/html' href='https://git.toradex.cn/cgit/linux-toradex.git/commit/?id=2433647bc8d983a543e7d31b41ca2de1c7e2c198'/>
<id>2433647bc8d983a543e7d31b41ca2de1c7e2c198</id>
<content type='text'>
This switches the airtime scheduler in mac80211 to use a virtual
time-based scheduler instead of the round-robin scheduler used before.
This has a couple of advantages:

- No need to sync up the round-robin scheduler in firmware/hardware with
  the round-robin airtime scheduler.

- If several stations are eligible for transmission we can schedule both
  of them; no need to hard-block the scheduling rotation until the head
  of the queue has used up its quantum.

- The check of whether a station is eligible for transmission becomes
  simpler (in ieee80211_txq_may_transmit()).

The drawback is that scheduling becomes slightly more expensive, as we
need to maintain an rbtree of TXQs sorted by virtual time. This means
that ieee80211_register_airtime() becomes O(logN) in the number of
currently scheduled TXQs because it can change the order of the
scheduled stations. We mitigate this overhead by only resorting when a
station changes position in the tree, and hopefully N rarely grows too
big (it's only TXQs currently backlogged, not all associated stations),
so it shouldn't be too big of an issue.

To prevent divisions in the fast path, we maintain both station sums and
pre-computed reciprocals of the sums. This turns the fast-path operation
into a multiplication, with divisions only happening as the number of
active stations change (to re-compute the current sum of all active
station weights). To prevent this re-computation of the reciprocal from
happening too frequently, we use a time-based notion of station
activity, instead of updating the weight every time a station gets
scheduled or de-scheduled. As queues can oscillate between empty and
occupied quite frequently, this can significantly cut down on the number
of re-computations. It also has the added benefit of making the station
airtime calculation independent on whether the queue happened to have
drained at the time an airtime value was accounted.

Co-developed-by: Yibo Zhao &lt;yiboz@codeaurora.org&gt;
Signed-off-by: Yibo Zhao &lt;yiboz@codeaurora.org&gt;
Signed-off-by: Toke Høiland-Jørgensen &lt;toke@redhat.com&gt;
Link: https://lore.kernel.org/r/20210623134755.235545-1-toke@redhat.com
Signed-off-by: Johannes Berg &lt;johannes.berg@intel.com&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
This switches the airtime scheduler in mac80211 to use a virtual
time-based scheduler instead of the round-robin scheduler used before.
This has a couple of advantages:

- No need to sync up the round-robin scheduler in firmware/hardware with
  the round-robin airtime scheduler.

- If several stations are eligible for transmission we can schedule both
  of them; no need to hard-block the scheduling rotation until the head
  of the queue has used up its quantum.

- The check of whether a station is eligible for transmission becomes
  simpler (in ieee80211_txq_may_transmit()).

The drawback is that scheduling becomes slightly more expensive, as we
need to maintain an rbtree of TXQs sorted by virtual time. This means
that ieee80211_register_airtime() becomes O(logN) in the number of
currently scheduled TXQs because it can change the order of the
scheduled stations. We mitigate this overhead by only resorting when a
station changes position in the tree, and hopefully N rarely grows too
big (it's only TXQs currently backlogged, not all associated stations),
so it shouldn't be too big of an issue.

To prevent divisions in the fast path, we maintain both station sums and
pre-computed reciprocals of the sums. This turns the fast-path operation
into a multiplication, with divisions only happening as the number of
active stations change (to re-compute the current sum of all active
station weights). To prevent this re-computation of the reciprocal from
happening too frequently, we use a time-based notion of station
activity, instead of updating the weight every time a station gets
scheduled or de-scheduled. As queues can oscillate between empty and
occupied quite frequently, this can significantly cut down on the number
of re-computations. It also has the added benefit of making the station
airtime calculation independent on whether the queue happened to have
drained at the time an airtime value was accounted.

Co-developed-by: Yibo Zhao &lt;yiboz@codeaurora.org&gt;
Signed-off-by: Yibo Zhao &lt;yiboz@codeaurora.org&gt;
Signed-off-by: Toke Høiland-Jørgensen &lt;toke@redhat.com&gt;
Link: https://lore.kernel.org/r/20210623134755.235545-1-toke@redhat.com
Signed-off-by: Johannes Berg &lt;johannes.berg@intel.com&gt;
</pre>
</div>
</content>
</entry>
</feed>
