Allow distinguishing the non-station case from the case of a
station without rates, by using -1 for the non-station case.
This value cannot be reached with a station since that many
legacy rates don't exist.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: Emmanuel Grumbach <emmanuel.grumbach@intel.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
As WMM is required for HT/VHT operation, treat bad WMM parameters
more gracefully by falling back to default parameters instead of
not using WMM assocation. This makes it possible to still use HT
or VHT, although potentially with reduced quality of service due
to unintended WMM parameters.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Disabling WMM has a huge impact these days. It implies that
HT and VHT will be disabled which means that the throughput
will be drammatically reduced.
Since the AIFSN is a transmission parameter, we can play a
bit and fix it up to make it compliant with the 802.11
specification which requires it to be at least 2.
Increasing it from 1 to 2 will slightly reduce the
likelyhood to get a transmission opportunity compared to
other clients that would accept to set AIFSN=1, but at
least it will allow HT and VHT which is a huge gain.
Signed-off-by: Emmanuel Grumbach <emmanuel.grumbach@intel.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
The function currently determines this value, for use in bss_info.qos,
based on the interface type itself. Make it a parameter instead and
set it with the same logic for now.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
The previous patch changed mac80211 to always report an event
after a CQM RSSI reconfiguration. Document that as expected
behaviour in both the cfg80211 and mac80211 API.
Currently, iwlmvm already implements that behaviour; the other
drivers implementing CQM RSSI events may have to be changed.
This behaviour lets userspace know what the current state is
without relying on querying the data which is racy.
Reviewed-by: Sharon, Sara <sara.sharon@intel.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
llid_in_use needs to be limited to stations of the same VIF, otherwise it
will cause a NULL deref as the sta_info of non-mesh-VIFs don't have
sta->mesh set.
Steps to reproduce:
modprobe mac80211_hwsim channels=2
iw phy phy0 interface add ibss0 type ibss
iw phy phy0 interface add mesh0 type mp
iw phy phy1 interface add ibss1 type ibss
iw phy phy1 interface add mesh1 type mp
ip link set ibss0 up
ip link set mesh0 up
ip link set ibss1 up
ip link set mesh1 up
iw dev ibss0 ibss join foo 2412
iw dev ibss1 ibss join foo 2412
# Ensure that ibss0 and ibss1 are actually associated; I often need to
# leave and join the cell on ibss1 a second time.
iw dev mesh0 mesh join bar
iw dev mesh1 mesh join bar # crash
Signed-off-by: Matthias Schiffer <mschiffer@universe-factory.net>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
When 11n peers performs a TDLS connection on a legacy BSS, the HT
operation IE must be specified according to IEEE802.11-2012 section
9.23.3.2. Otherwise HT-protection is compromised and the medium becomes
noisy for both the TDLS and the BSS links.
Signed-off-by: Arik Nemtsov <arikx.nemtsov@intel.com>
Signed-off-by: Emmanuel Grumbach <emmanuel.grumbach@intel.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Scheduled scan has to be reconfigured only if wowlan wasn't
configured, since otherwise it should continue to run (with
the 'any' trigger) or be aborted.
The current code will end up asking the driver to start a new
scheduled scan without stopping the previous one, and leaking
some memory (from the previous request.)
Fix this by doing the abort/restart under the proper conditions.
Signed-off-by: Eliad Peller <eliadx.peller@intel.com>
Signed-off-by: Emmanuel Grumbach <emmanuel.grumbach@intel.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
If drv_start() fails during hw_restart, all the running
interfaces are being closed/stopped, which results in
drv_stop() being called, although the driver was never
started successfully.
This might cause drivers to perform operations on uninitialized
memory (as they assume it was initialized on drv_start)
Consider the local->started flag, and call the driver's stop()
op only if drv_start() succeeded before.
Move drv_start() and drv_stop() to driver-ops.c, as they are no
longer simple wrappers.
Signed-off-by: Eliad Peller <eliadx.peller@intel.com>
Signed-off-by: Emmanuel Grumbach <emmanuel.grumbach@intel.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
The recalc_smps work can run after the station disassociates.
At this stage we already released the channel, but the work
will be cancelled only when the interface stops.
In this scenario we can hit the warning in ieee80211_recalc_smps, so
just remove it.
Signed-off-by: Andrei Otcheretianski <andrei.otcheretianski@intel.com>
Signed-off-by: Emmanuel Grumbach <emmanuel.grumbach@intel.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Requesting hw restart during suspend might result
in the restart work being executed after mac80211
and the hw are suspended.
Solve the race by simply scheduling the restart
work on a freezable workqueue.
Note that there can be some cases of reconfiguration
on resume (besides the hardware restart):
* wowlan is not configured -
All the interfaces removed were removed on suspend,
and drv_stop() was called. At this point the driver
shouldn't expect for hw_restart anyway, so we can
simply cancel it (on resume).
* wowlan is configured, drv_resume() == 1
There is no definitive expected behavior in this case,
as each driver might have different expectations (e.g.
setting some flags on suspend/restart vs. not handling
spurious recovery).
For now, simply let the hw_restart work run again after
resume, and hope the driver will handle it well (or at
least initiate another hw restart).
Signed-off-by: Eliad Peller <eliadx.peller@intel.com>
Signed-off-by: Emmanuel Grumbach <emmanuel.grumbach@intel.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Local request to deauthenticate wasn't handled while associating, thus
the association could continue even when the user space required to
disconnect.
Cc: stable@vger.kernel.org
Signed-off-by: Andrei Otcheretianski <andrei.otcheretianski@intel.com>
Signed-off-by: Emmanuel Grumbach <emmanuel.grumbach@intel.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
In TDLS channel-switch operations the chandef can sometimes be NULL.
Avoid an oops in the trace code for these cases and just print a
chandef full of zeros.
Cc: stable@vger.kernel.org
Fixes: a7a6bdd067 ("mac80211: introduce TDLS channel switch ops")
Signed-off-by: Arik Nemtsov <arikx.nemtsov@intel.com>
Signed-off-by: Emmanuel Grumbach <emmanuel.grumbach@intel.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
If parse_acl_data succeeds but the subsequent parsing of smps
attributes fails, there will be a memory leak due to early returns.
Fix that by moving the ACL parsing later.
Cc: stable@vger.kernel.org
Fixes: 18998c381b ("cfg80211: allow requesting SMPS mode on ap start")
Signed-off-by: Ola Olsson <ola.olsson@sonymobile.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
In case of one shot NOA the interval can be 0, catch that
instead of potentially (depending on the driver) crashing
like this:
divide error: 0000 [#1] SMP
[...]
Call Trace:
<IRQ>
[<ffffffffc08e891c>] ieee80211_extend_absent_time+0x6c/0xb0 [mac80211]
[<ffffffffc08e8a17>] ieee80211_update_p2p_noa+0xb7/0xe0 [mac80211]
[<ffffffffc069cc30>] ath9k_p2p_ps_timer+0x170/0x190 [ath9k]
[<ffffffffc070adf8>] ath_gen_timer_isr+0xc8/0xf0 [ath9k_hw]
[<ffffffffc0691156>] ath9k_tasklet+0x296/0x2f0 [ath9k]
[<ffffffff8107ad65>] tasklet_action+0xe5/0xf0
[...]
Cc: stable@vger.kernel.org [3.16+, due to d463af4a1c using it]
Signed-off-by: Janusz Dziedzic <janusz.dziedzic@tieto.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
* I merged net-next back to avoid a conflict with the
* cfg80211 scheduled scan API extensions
* preparations for better scan result timestamping
* regulatory cleanups
* mac80211 statistics cleanups
* a few other small cleanups and fixes
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Merge tag 'mac80211-next-for-davem-2015-10-21' of git://git.kernel.org/pub/scm/linux/kernel/git/jberg/mac80211-next
Johannes Berg says:
====================
Here's another set of patches for the current cycle:
* I merged net-next back to avoid a conflict with the
* cfg80211 scheduled scan API extensions
* preparations for better scan result timestamping
* regulatory cleanups
* mac80211 statistics cleanups
* a few other small cleanups and fixes
====================
Signed-off-by: David S. Miller <davem@davemloft.net>
the global Soc configuration is treated by syscon, and sub ctrl bus is
Soc bus. it has to be treated by syscon.
Signed-off-by: yankejian <yankejian@huawei.com>
Signed-off-by: lisheng <lisheng011@huawei.com>
Signed-off-by: lipeng <lipeng321@huawei.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Hariprasad Shenai says:
====================
Trivial fixes for cxgb4 driver
This patch series updates driver description for next gen. adapters, updates
firmware info., returns error for setup_rss error case, restores L1
configuration in case of FW rejects new config, updates and aligns ethtool
get stats settings, etc
This patch series has been created against net-next tree and includes
patches on cxgb4 and cxgb4vf driver.
We have included all the maintainers of respective drivers. Kindly review
the change and let us know in case of any review comments.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>
Update ethtool get_drvinfo to display regdump len and also update
firmware string version print to display N/A in case FW isn't present
Signed-off-by: Hariprasad Shenai <hariprasad@chelsio.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
In the ethtool set_settings() routine we need to remember our old L1
Configuration in case the firmware rejects the request and then restore
that.
Signed-off-by: Hariprasad Shenai <hariprasad@chelsio.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
For {1, 10, 40} Gb/s. Prohibiting turning off autonegotiation isn't anywhere
in the standard.
Signed-off-by: Hariprasad Shenai <hariprasad@chelsio.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Align the ethtool get stats settings with the rest so it looks uniform
Signed-off-by: Hariprasad Shenai <hariprasad@chelsio.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
With use of lwtunnel, we can directly call dev_queue_xmit()
rather than calling netdev vport send operation.
Following change make tunnel vport code bit cleaner.
Signed-off-by: Pravin B Shelar <pshelar@nicira.com>
Acked-by: Thomas Graf <tgraf@suug.ch>
Acked-by: Jiri Benc <jbenc@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Patch fixes following sparse warning.
net/openvswitch/flow_netlink.c:583:30: warning: incorrect type in assignment (different base types)
net/openvswitch/flow_netlink.c:583:30: expected restricted __be16 [usertype] ipv4
net/openvswitch/flow_netlink.c:583:30: got int
Fixes: 6b26ba3a7d ("openvswitch: netlink attributes for IPv6 tunneling")
Signed-off-by: Pravin B Shelar <pshelar@nicira.com>
Acked-by: Thomas Graf <tgraf@suug.ch>
Acked-by: Jiri Benc <jbenc@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Alexei Starovoitov says:
====================
bpf_perf_event_output helper
Over the last year there were multiple attempts to let eBPF programs
output data into perf events by He Kuang and Wangnan.
The last one was:
https://lkml.org/lkml/2015/7/20/736
It was almost perfect with exception that all bpf programs would sent
data into one global perf_event.
This patch set takes different approach by letting user space
open independent PERF_COUNT_SW_BPF_OUTPUT events, so that program
output won't collide.
Wangnan is working on corresponding perf patches.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>
Performance test and example of bpf_perf_event_output().
kprobe is attached to sys_write() and trivial bpf program streams
pid+cookie into userspace via PERF_COUNT_SW_BPF_OUTPUT event.
Usage:
$ sudo ./bld_x64/samples/bpf/trace_output
recv 2968913 events per sec
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
This helper is used to send raw data from eBPF program into
special PERF_TYPE_SOFTWARE/PERF_COUNT_SW_BPF_OUTPUT perf_event.
User space needs to perf_event_open() it (either for one or all cpus) and
store FD into perf_event_array (similar to bpf_perf_event_read() helper)
before eBPF program can send data into it.
Today the programs triggered by kprobe collect the data and either store
it into the maps or print it via bpf_trace_printk() where latter is the debug
facility and not suitable to stream the data. This new helper replaces
such bpf_trace_printk() usage and allows programs to have dedicated
channel into user space for post-processing of the raw data collected.
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Instead of WARN_ON in perf_event_output() on unpaded raw samples,
pad them automatically.
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
In the ipv4 outbound path of an ipvlan device in l3 mode, the ifindex is
being grabbed from dev_get_iflink. This works for the physical device
case, since as the documentation of that function notes: "Physical
interfaces have the same 'ifindex' and 'iflink' values.". However, if
the master device is a veth, and the pairs are in separate net
namespaces, the route lookup will fail with -ENODEV due to outer veth
pair being in a separate namespace from the ipvlan master/routing
namespace.
ns0 | ns1 | ns2
veth0a--|--veth0b--|--ipvl0
In ipvlan_process_v4_outbound(), a packet sent from ipvl0 in the above
configuration will pass fl.flowi4_oif == veth0a to
ip_route_output_flow(), but *net == ns1.
Notice also that ipv6 processing is not using iflink. Since there is a
discrepancy in usage, fixup both v4 and v6 case to use local dev
variable.
Tested this with l3 ipvlan on top of veth, as well as with single
physical interface in the top namespace.
Signed-off-by: Brenden Blanco <bblanco@plumgrid.com>
Reviewed-by: Jiri Benc <jbenc@redhat.com>
Acked-by: Mahesh Bandewar <maheshb@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Allowing an application to set whatever limit for
the list of recently RST fastopen sessions [1] is not wise,
as it open ways to deplete kernel memory.
Cap the user provided limit by somaxconn sysctl,
like listen() backlog.
[1] https://tools.ietf.org/html/rfc7413#section-5.1
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This header file only contains the platform data structure definition,
so move it to the include/linux/platform_data/ directory.
Signed-off-by: Vivien Didelot <vivien.didelot@savoirfairelinux.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Remove the inclusion of linux/mdio-gpio.h in nas4220b, wbd111 and wbd222
boards since mdio-gpio is not used.
Signed-off-by: Vivien Didelot <vivien.didelot@savoirfairelinux.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
drivers/net/ethernet/hisilicon/hns/hnae.c:442:1-3: WARNING: PTR_ERR_OR_ZERO can be used
Use PTR_ERR_OR_ZERO rather than if(IS_ERR(...)) + PTR_ERR
Generated by: scripts/coccinelle/api/ptr_ret.cocci
CC: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Fengguang Wu <fengguang.wu@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Tom Herbert added SIT support to GRO with commit
19424e052f ("sit: Add gro callbacks to sit_offload"),
later reverted by Herbert Xu.
The problem came because Tom patch was building GRO
packets without proper meta data : If packets were locally
delivered, we would not care.
But if packets needed to be forwarded, GSO engine was not
able to segment individual segments.
With the following patch, we correctly set skb->encapsulation
and inner network header. We also update gso_type.
Tested:
Server :
netserver
modprobe dummy
ifconfig dummy0 8.0.0.1 netmask 255.255.255.0 up
arp -s 8.0.0.100 4e:32:51:04:47:e5
iptables -I INPUT -s 10.246.7.151 -j TEE --gateway 8.0.0.100
ifconfig sixtofour0
sixtofour0 Link encap:IPv6-in-IPv4
inet6 addr: 2002:af6:798::1/128 Scope:Global
inet6 addr: 2002:af6:798::/128 Scope:Global
UP RUNNING NOARP MTU:1480 Metric:1
RX packets:411169 errors:0 dropped:0 overruns:0 frame:0
TX packets:409414 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:0
RX bytes:20319631739 (20.3 GB) TX bytes:29529556 (29.5 MB)
Client :
netperf -H 2002:af6:798::1 -l 1000 &
Checked on server traffic copied on dummy0 and verify segments were
properly rebuilt, with proper IP headers, TCP checksums...
tcpdump on eth0 shows proper GRO aggregation takes place.
Signed-off-by: Eric Dumazet <edumazet@google.com>
Acked-by: Tom Herbert <tom@herbertland.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
While testing my SIT/GRO patch using netfilter TEE module and a dummy
device, I found some features were missing :
TSO IPv6, UFO, and encapsulated traffic.
ethtool -k dummy0 now gives :
...
tcp-segmentation-offload: on
tx-tcp-segmentation: on
tx-tcp-ecn-segmentation: on
tx-tcp6-segmentation: on
udp-fragmentation-offload: on
...
tx-gre-segmentation: on
tx-ipip-segmentation: on
tx-sit-segmentation: on
tx-udp_tnl-segmentation: on
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
if_nlmsg_size() overestimates the minimum allocation size of netlink
dump request (when called from rtnl_calcit()) or the size of the
message (when called from rtnl_getlink()). This is because
ext_filter_mask is not supported by rtnl_link_get_af_size() and
rtnl_link_get_size().
The over-estimation is significant when at least one netdev has many
VLANs configured (8 bytes for each configured VLAN).
This patch-set "rightsizes" the protocol specific attribute size
calculation by propagating ext_filter_mask to rtnl_link_get_af_size()
and adding this a argument to get_link_af_size op in rtnl_af_ops.
Bridge module already used filtering aware sizing for notifications.
br_get_link_af_size_filtered() is consistent with the modified
get_link_af_size op so it replaces br_get_link_af_size() in br_af_ops.
br_get_link_af_size() becomes unused and thus removed.
Signed-off-by: Ronen Arad <ronen.arad@intel.com>
Acked-by: Sridhar Samudrala <sridhar.samudrala@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Configure ageing time to the HW for newly bridged device
CC: Scott Feldman <sfeldma@gmail.com>
CC: Jiri Pirko <jiri@resnulli.us>
Signed-off-by: Elad Raz <eladr@mellanox.com>
Acked-by: Jiri Pirko <jiri@mellanox.com>
Acked-by: Scott Feldman <sfeldma@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Yuchung Cheng says:
====================
RACK loss detection
RACK (Recent ACK) loss recovery uses the notion of time instead of
packet sequence (FACK) or counts (dupthresh).
It's inspired by the FACK heuristic in tcp_mark_lost_retrans(): when a
limited transmit (new data packet) is sacked in recovery, then any
retransmission sent before that newly sacked packet was sent must have
been lost, since at least one round trip time has elapsed.
But that existing heuristic from tcp_mark_lost_retrans()
has several limitations:
1) it can't detect tail drops since it depends on limited transmit
2) it's disabled upon reordering (assumes no reordering)
3) it's only enabled in fast recovery but not timeout recovery
RACK addresses these limitations with a core idea: an unacknowledged
packet P1 is deemed lost if a packet P2 that was sent later is is
s/acked, since at least one round trip has passed.
Since RACK cares about the time sequence instead of the data sequence
of packets, it can detect tail drops when a later retransmission is
s/acked, while FACK or dupthresh can't. For reordering RACK uses a
dynamically adjusted reordering window ("reo_wnd") to reduce false
positives on ever (small) degree of reordering, similar to the delayed
Early Retransmit.
In the current patch set RACK is only a supplemental loss detection
and does not trigger fast recovery. However we are developing RACK
to replace or consolidate FACK/dupthresh, early retransmit, and
thin-dupack. These heuristics all implicitly bear the time notion.
For example, the delayed Early Retransmit is simply applying RACK
to trigger the fast recovery with small inflight.
RACK requires measuring the minimum RTT. Tracking a global min is less
robust due to traffic engineering pathing changes. Therefore it uses a
windowed filter by Kathleen Nichols. The min RTT can also be useful
for various other purposes like congestion control or stat monitoring.
This patch has been used on Google servers for well over 1 year. RACK
has also been implemented in the QUIC protocol. We are submitting an
IETF draft as well.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>
This patch implements the second half of RACK that uses the the most
recent transmit time among all delivered packets to detect losses.
tcp_rack_mark_lost() is called upon receiving a dubious ACK.
It then checks if an not-yet-sacked packet was sent at least
"reo_wnd" prior to the sent time of the most recently delivered.
If so the packet is deemed lost.
The "reo_wnd" reordering window starts with 1msec for fast loss
detection and changes to min-RTT/4 when reordering is observed.
We found 1msec accommodates well on tiny degree of reordering
(<3 pkts) on faster links. We use min-RTT instead of SRTT because
reordering is more of a path property but SRTT can be inflated by
self-inflicated congestion. The factor of 4 is borrowed from the
delayed early retransmit and seems to work reasonably well.
Since RACK is still experimental, it is now used as a supplemental
loss detection on top of existing algorithms. It is only effective
after the fast recovery starts or after the timeout occurs. The
fast recovery is still triggered by FACK and/or dupack threshold
instead of RACK.
We introduce a new sysctl net.ipv4.tcp_recovery for future
experiments of loss recoveries. For now RACK can be disabled by
setting it to 0.
Signed-off-by: Yuchung Cheng <ycheng@google.com>
Signed-off-by: Neal Cardwell <ncardwell@google.com>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This patch is the first half of the RACK loss recovery.
RACK loss recovery uses the notion of time instead
of packet sequence (FACK) or counts (dupthresh). It's inspired by the
previous FACK heuristic in tcp_mark_lost_retrans(): when a limited
transmit (new data packet) is sacked, then current retransmitted
sequence below the newly sacked sequence must been lost,
since at least one round trip time has elapsed.
But it has several limitations:
1) can't detect tail drops since it depends on limited transmit
2) is disabled upon reordering (assumes no reordering)
3) only enabled in fast recovery ut not timeout recovery
RACK (Recently ACK) addresses these limitations with the notion
of time instead: a packet P1 is lost if a later packet P2 is s/acked,
as at least one round trip has passed.
Since RACK cares about the time sequence instead of the data sequence
of packets, it can detect tail drops when later retransmission is
s/acked while FACK or dupthresh can't. For reordering RACK uses a
dynamically adjusted reordering window ("reo_wnd") to reduce false
positives on ever (small) degree of reordering.
This patch implements tcp_advanced_rack() which tracks the
most recent transmission time among the packets that have been
delivered (ACKed or SACKed) in tp->rack.mstamp. This timestamp
is the key to determine which packet has been lost.
Consider an example that the sender sends six packets:
T1: P1 (lost)
T2: P2
T3: P3
T4: P4
T100: sack of P2. rack.mstamp = T2
T101: retransmit P1
T102: sack of P2,P3,P4. rack.mstamp = T4
T205: ACK of P4 since the hole is repaired. rack.mstamp = T101
We need to be careful about spurious retransmission because it may
falsely advance tp->rack.mstamp by an RTT or an RTO, causing RACK
to falsely mark all packets lost, just like a spurious timeout.
We identify spurious retransmission by the ACK's TS echo value.
If TS option is not applicable but the retransmission is acknowledged
less than min-RTT ago, it is likely to be spurious. We refrain from
using the transmission time of these spurious retransmissions.
The second half is implemented in the next patch that marks packet
lost using RACK timestamp.
Signed-off-by: Yuchung Cheng <ycheng@google.com>
Signed-off-by: Neal Cardwell <ncardwell@google.com>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
a helper to prepare the first main RACK patch.
Signed-off-by: Yuchung Cheng <ycheng@google.com>
Signed-off-by: Neal Cardwell <ncardwell@google.com>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
a helper to prepare the main RACK patch
Signed-off-by: Yuchung Cheng <ycheng@google.com>
Signed-off-by: Neal Cardwell <ncardwell@google.com>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Remove the existing lost retransmit detection because RACK subsumes
it completely. This also stops the overloading the ack_seq field of
the skb control block.
Signed-off-by: Yuchung Cheng <ycheng@google.com>
Signed-off-by: Neal Cardwell <ncardwell@google.com>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Kathleen Nichols' algorithm for tracking the minimum RTT of a
data stream over some measurement window. It uses constant space
and constant time per update. Yet it almost always delivers
the same minimum as an implementation that has to keep all
the data in the window. The measurement window is tunable via
sysctl.net.ipv4.tcp_min_rtt_wlen with a default value of 5 minutes.
The algorithm keeps track of the best, 2nd best & 3rd best min
values, maintaining an invariant that the measurement time of
the n'th best >= n-1'th best. It also makes sure that the three
values are widely separated in the time window since that bounds
the worse case error when that data is monotonically increasing
over the window.
Upon getting a new min, we can forget everything earlier because
it has no value - the new min is less than everything else in the
window by definition and it's the most recent. So we restart fresh
on every new min and overwrites the 2nd & 3rd choices. The same
property holds for the 2nd & 3rd best.
Therefore we have to maintain two invariants to maximize the
information in the samples, one on values (1st.v <= 2nd.v <=
3rd.v) and the other on times (now-win <=1st.t <= 2nd.t <= 3rd.t <=
now). These invariants determine the structure of the code
The RTT input to the windowed filter is the minimum RTT measured
from ACK or SACK, or as the last resort from TCP timestamps.
The accessor tcp_min_rtt() returns the minimum RTT seen in the
window. ~0U indicates it is not available. The minimum is 1usec
even if the true RTT is below that.
Signed-off-by: Yuchung Cheng <ycheng@google.com>
Signed-off-by: Neal Cardwell <ncardwell@google.com>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Currently ca_seq_rtt_us does not use Kern's check. Fix that by
checking if any packet acked is a retransmit, for both RTT used
for RTT estimation and congestion control.
Fixes: 5b08e47ca ("tcp: prefer packet timing to TS-ECR for RTT")
Signed-off-by: Yuchung Cheng <ycheng@google.com>
Signed-off-by: Neal Cardwell <ncardwell@google.com>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Jeff Kirsher says:
====================
Intel Wired LAN Driver Updates 2015-10-19
This series contains updates to i40e and i40evf only.
Kiran adds a spinlock around code accessing VSI MAC filter list to
ensure that we are synchronizing access to the filter list, otherwise
we can end up with multiple accesses at the same time which can cause
the VSI MAC filter list to get in an unstable or corrupted state.
Jesse fixes overlong BIT defines, where the RSS enabling call were
mistakenly missed. Also fixes a bug where the enable function was
enabling the interrupt twice while trying to update the two interrupt
throttle rate thresholds for Rx and Tx, while refactoring the IRQ
enable function to simplify reading the flow. Addressed the high
CPU utilization of some small streaming workloads that the driver should
reduce CPU in.
Anjali fixes two X722 issues with respect to EEPROM checksum verify and
reading NVM version info. Fixed where a mask value was accidentally
replaced with a bit mask causing Flow Director sideband to be broken.
Alex Duyck fixes areas of the drivers which run from hard interrupt
context or with interrupts already disabled in netpoll, so use
napi_schedule_irqoff() instead of napi_schedule().
Mitch fixes the VF drivers to not easily give up when it is not able
to communicate with the PF driver.
Carolyn fixes a problem where our tools MAC loopback test, after driver
unbind would fail because the hardware was configured for multiqueue and
unbind operation did not clear this configuration. Also fixed a issue
where the NVMUpdate tool gets bad data from the PHY when using the PHY
NVM feature because of contention on the MDIO interface from getting
PHY capability calls from the driver during regular operations.
Catherine fixed an issue where we were checking if autoneg was allowed
to change before checking if autoneg was changing, these checks need to
be in the reverse order.
Jean Sacren fixes up an function header comment to align the kernel-docs
with the actual code.
v2: Cleaned up the use of spin_is_locked() in patch 1 based on feedback
from David Miller, since it always evaluates to zero on uni-processor
builds
====================
Signed-off-by: David S. Miller <davem@davemloft.net>
