linux-toradex.git/include/uapi/linux/snmp.h, branch v6.4-rc1

icmp: Add counters for rate limits

2023-01-26T09:52:18+00:00

There are multiple ICMP rate limiting mechanisms:

* Global limits: net.ipv4.icmp_msgs_burst/icmp_msgs_per_sec
* v4 per-host limits: net.ipv4.icmp_ratelimit/ratemask
* v6 per-host limits: net.ipv6.icmp_ratelimit/ratemask

However, when ICMP output is limited, there is no way to tell
which limit has been hit or even if the limits are responsible
for the lack of ICMP output.

Add counters for each of the cases above. As we are within
local_bh_disable(), use the __INC stats variant.

Example output:

 # nstat -sz "*RateLimit*"
 IcmpOutRateLimitGlobal          134                0.0
 IcmpOutRateLimitHost            770                0.0
 Icmp6OutRateLimitHost           84                 0.0

Signed-off-by: Jamie Bainbridge 
Suggested-by: Abhishek Rawal 
Link: https://lore.kernel.org/r/273b32241e6b7fdc5c609e6f5ebc68caf3994342.1674605770.git.jamie.bainbridge@gmail.com
Signed-off-by: Paolo Abeni

tcp: add u32 counter in tcp_sock and an SNMP counter for PLB

2022-10-28T09:47:42+00:00

A u32 counter is added to tcp_sock for counting the number of PLB
triggered rehashes for a TCP connection. An SNMP counter is also
added to count overall PLB triggered rehash events for a host. These
counters are hooked up to PLB implementation for DCTCP.

TCP_NLA_REHASH is added to SCM_TIMESTAMPING_OPT_STATS that reports
the rehash attempts triggered due to PLB or timeouts. This gives
a historical view of sustained congestion or timeouts experienced
by the TCP connection.

Signed-off-by: Mubashir Adnan Qureshi 
Signed-off-by: Yuchung Cheng 
Signed-off-by: Neal Cardwell 
Reviewed-by: Eric Dumazet 
Signed-off-by: David S. Miller

tls: rx: add counter for NoPad violations

2022-07-12T02:48:33+00:00

As discussed with Maxim add a counter for true NoPad violations.
This should help deployments catch unexpected padded records vs
just control records which always need re-encryption.

https: //lore.kernel.org/all/b111828e6ac34baad9f4e783127eba8344ac252d.camel@nvidia.com/
Signed-off-by: Jakub Kicinski

tls: fix spelling of MIB

2022-07-12T02:48:32+00:00

MIN -> MIB

Fixes: 88527790c079 ("tls: rx: add sockopt for enabling optimistic decrypt with TLS 1.3")
Signed-off-by: Jakub Kicinski

tls: rx: add sockopt for enabling optimistic decrypt with TLS 1.3

2022-07-06T11:56:35+00:00

Since optimisitic decrypt may add extra load in case of retries
require socket owner to explicitly opt-in.

Signed-off-by: Jakub Kicinski 
Signed-off-by: David S. Miller

tcp: Add stats for socket migration.

2021-06-23T19:56:08+00:00

This commit adds two stats for the socket migration feature to evaluate the
effectiveness: LINUX_MIB_TCPMIGRATEREQ(SUCCESS|FAILURE).

If the migration fails because of the own_req race in receiving ACK and
sending SYN+ACK paths, we do not increment the failure stat. Then another
CPU is responsible for the req.

Link: https://lore.kernel.org/bpf/CAK6E8=cgFKuGecTzSCSQ8z3YJ_163C0uwO9yRvfDSE7vOe9mJA@mail.gmail.com/
Suggested-by: Yuchung Cheng 
Signed-off-by: Kuniyuki Iwashima 
Acked-by: Yuchung Cheng 
Signed-off-by: David S. Miller

net: udp: introduce UDP_MIB_MEMERRORS for udp_mem

2020-11-09T23:34:44+00:00

When udp_memory_allocated is at the limit, __udp_enqueue_schedule_skb
will return a -ENOBUFS, and skb will be dropped in __udp_queue_rcv_skb
without any counters being done. It's hard to find out what happened
once this happen.

So we introduce a UDP_MIB_MEMERRORS to do this job. Well, this change
looks friendly to the existing users, such as netstat:

$ netstat -u -s
Udp:
    0 packets received
    639 packets to unknown port received.
    158689 packet receive errors
    180022 packets sent
    RcvbufErrors: 20930
    MemErrors: 137759
UdpLite:
IpExt:
    InOctets: 257426235
    OutOctets: 257460598
    InNoECTPkts: 181177

v2:
- Fix some alignment problems

Signed-off-by: Menglong Dong 
Link: https://lore.kernel.org/r/1604627354-43207-1-git-send-email-dong.menglong@zte.com.cn
Signed-off-by: Jakub Kicinski

tcp: skip DSACKs with dubious sequence ranges

2020-09-25T03:15:45+00:00

Currently, we use length of DSACKed range to compute number of
delivered packets. And if sequence range in DSACK is corrupted,
we can get bogus dsacked/acked count, and bogus cwnd.

This patch put bounds on DSACKed range to skip update of data
delivery and spurious retransmission information, if the DSACK
is unlikely caused by sender's action:
- DSACKed range shouldn't be greater than maximum advertised rwnd.
- Total no. of DSACKed segments shouldn't be greater than total
  no. of retransmitted segs. Unlike spurious retransmits, network
  duplicates or corrupted DSACKs shouldn't be counted as delivery.

Signed-off-by: Priyaranjan Jha 
Signed-off-by: Neal Cardwell 
Signed-off-by: Yuchung Cheng 
Signed-off-by: Eric Dumazet 
Signed-off-by: David S. Miller

tcp: add SNMP counter for no. of duplicate segments reported by DSACK

2020-07-17T19:54:30+00:00

There are two existing SNMP counters, TCPDSACKRecv and TCPDSACKOfoRecv,
which are incremented depending on whether the DSACKed range is below
the cumulative ACK sequence number or not. Unfortunately, these both
implicitly assume each DSACK covers only one segment. This makes these
counters unusable for estimating spurious retransmit rates,
or real/non-spurious loss rate.

This patch introduces a new SNMP counter, TCPDSACKRecvSegs, which tracks
the estimated number of duplicate segments based on:
(DSACKed sequence range) / MSS. This counter is usable for estimating
spurious retransmit rates, or real/non-spurious loss rate.

Signed-off-by: Priyaranjan Jha 
Signed-off-by: Neal Cardwell 
Signed-off-by: Yuchung Cheng 
Signed-off-by: Soheil Hassas Yeganeh 
Signed-off-by: David S. Miller

tcp: export count for rehash attempts

2020-01-26T14:28:47+00:00

Using IPv6 flow-label to swiftly route around avoid congested or
disconnected network path can greatly improve TCP reliability.

This patch adds SNMP counters and a OPT_STATS counter to track both
host-level and connection-level statistics. Network administrators
can use these counters to evaluate the impact of this new ability better.

Export count for rehash attempts to
1) two SNMP counters: TcpTimeoutRehash (rehash due to timeouts),
   and TcpDuplicateDataRehash (rehash due to receiving duplicate
   packets)
2) Timestamping API SOF_TIMESTAMPING_OPT_STATS.

Signed-off-by: Abdul Kabbani 
Signed-off-by: Neal Cardwell 
Signed-off-by: Yuchung Cheng 
Signed-off-by: Kevin(Yudong) Yang 
Signed-off-by: Eric Dumazet 
Signed-off-by: David S. Miller