Commit Graph

928 Commits

Author SHA1 Message Date
Joachim Eastwood 75fee59550 stmmac: remove setup/free glue callbacks
As all dwmac-* drivers have been converted to have a proper probe
function the setup callback can now be removed. Also remove the
free callback that wasn't used by any driver.

New dwmac-* drivers should implement standard probe and remove
functions to preform any needed setup and teardown.

Signed-off-by: Joachim Eastwood <manabian@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-07-29 00:13:25 -07:00
Joachim Eastwood 0933328a1b stmmac: remove unused stmmac_of_data struct
As dwmac-* drivers that need OF match have been converted
to use their own internal OF match data structure this can
now be removed.

Signed-off-by: Joachim Eastwood <manabian@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-07-29 00:13:24 -07:00
Erik Kline 3985e8a361 ipv6: sysctl to restrict candidate source addresses
Per RFC 6724, section 4, "Candidate Source Addresses":

    It is RECOMMENDED that the candidate source addresses be the set
    of unicast addresses assigned to the interface that will be used
    to send to the destination (the "outgoing" interface).

Add a sysctl to enable this behaviour.

Signed-off-by: Erik Kline <ek@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-07-22 10:54:11 -07:00
David S. Miller f3120acc78 Merge branch 'master' of git://git.kernel.org/pub/scm/linux/kernel/git/jkirsher/next-queue
Jeff Kirsher says:

====================
Intel Wired LAN Driver Updates 2015-07-17

This series contains updates to igb, ixgbe, ixgbevf, i40e, bnx2x,
freescale, siena and dp83640.

Jacob provides several patches to clarify the intended way to implement
both SIOCSHWTSTAMP and ethtool's get_ts_info().  It is okay to support
the specific filters in SIOCSHWTSTAMP by upscaling them to the generic
filters.

Alex Duyck provides a igb patch to pull the time stamp from the fragment
before it gets added to the skb, to avoid a possible issue in which the
fragment can possibly be less than IGB_RX_HDR_LEN due to the time stamp
being pulled after the copybreak check.  Also provides a ixgbevf patch to
fold the ixgbevf_pull_tail() call into ixgbevf_add_rx_frag(), which gives
the advantage that the fragment does not have to be modified after it is
added to the skb.

Fan provides patches for ixgbe/ixgbevf to set the receive hash type
based on receive descriptor RSS type.

Todd provides a fix for igb where on check for link on any media other
than copper was not being detected since it was looking on the incorrect
PHY page (due to the page being used gets switched before the function
to check link gets executed).
====================

Signed-off-by: David S. Miller <davem@davemloft.net>
2015-07-20 20:50:19 -07:00
Joachim Eastwood f4c190eb8b stmmac: drop custom_* fields from plat_stmmacenet_data
Both of these fields are unused and has been unused since they
were added 3 and 5 years ago. Drop them since they are clearly
not very useful.

Signed-off-by: Joachim Eastwood <manabian@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-07-20 20:45:57 -07:00
Scott Feldman a48037e7c6 switchdev: update documentation for offload_fwd_mark
Signed-off-by: Scott Feldman <sfeldma@gmail.com>
Acked-by: Jiri Pirko <jiri@resnulli.us>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-07-20 18:32:45 -07:00
Jacob Keller eff3cddc22 clarify implementation of ethtool's get_ts_info op
This patch adds some clarification about the intended way to implement
both SIOCSHWTSTAMP and ethtool's get_ts_info. The HWTSTAMP API has
several Rx filters which are very specific, as well as more general
filters. The specific filters really only exist to support some broken
hardware which can't fully implement the generic filters. This patch
adds clarification that it is okay to support the specific filters in
SIOCSHWTSTAMP by upscaling them to the generic filters. In addition,
update the header for ethtool_ts_info to specify that drivers ought to
only report the filters they support without upscaling in this manner.

Signed-off-by: Jacob Keller <jacob.e.keller@intel.com>
Acked-by: Richard Cochran <richardcochran@gmail.com>
Tested-by: Phil Schmitt <phillip.j.schmitt@intel.com>
Reviewed-by: Aaron Brown <aaron.f.brown@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>
2015-07-17 19:59:04 -07:00
Stefan Tatschner 03bc7523cb can-doc: Fix wrong chapter reference
In f35f6c8f7 (can: update MAINTAINERS and Documentation) chapter 3.3
was removed. This patch fixes some old references to chapter 3.4 which
no longer exists.

Signed-off-by: Stefan Tatschner <stefan@sevenbyte.org>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2015-07-10 15:18:33 -06:00
Tom Herbert 35a256fee5 ipv6: Nonlocal bind
Add support to allow non-local binds similar to how this was done for IPv4.
Non-local binds are very useful in emulating the Internet in a box, etc.

This add the ip_nonlocal_bind sysctl under ipv6.

Testing:

Set up nonlocal binding and receive routing on a host, e.g.:

ip -6 rule add from ::/0 iif eth0 lookup 200
ip -6 route add local 2001:0:0:1::/64 dev lo proto kernel scope host table 200
sysctl -w net.ipv6.ip_nonlocal_bind=1

Set up routing to 2001:0:0:1::/64 on peer to go to first host

ping6 -I 2001:0:0:1::1 peer-address -- to verify

Signed-off-by: Tom Herbert <tom@herbertland.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-07-09 21:09:10 -07:00
Tejun Heo e2f15f9a79 netconsole: implement extended console support
printk logbuf keeps various metadata and optional key=value dictionary for
structured messages, both of which are stripped when messages are handed
to regular console drivers.

It can be useful to have this metadata and dictionary available to
netconsole consumers.  This obviously makes logging via netconsole more
complete and the sequence number in particular is useful in environments
where messages may be lost or reordered in transit - e.g.  when netconsole
is used to collect messages in a large cluster where packets may have to
travel congested hops to reach the aggregator.  The lost and reordered
messages can easily be identified and handled accordingly using the
sequence numbers.

printk recently added extended console support which can be selected by
setting CON_EXTENDED flag.  From console driver side, not much changes.
The only difference is that the text passed to the write callback is
formatted the same way as /dev/kmsg.

This patch implements extended console support for netconsole which can be
enabled by either prepending "+" to a netconsole boot param entry or
echoing 1 to "extended" file in configfs.  When enabled, netconsole
transmits extended log messages with headers identical to /dev/kmsg
output.

There's one complication due to message fragments.  netconsole limits the
maximum message size to 1k and messages longer than that are split into
multiple fragments.  As all extended console messages should carry
matching headers and be uniquely identifiable, each extended message
fragment carries full copy of the metadata and an extra header field to
identify the specific fragment.  The optional header is of the form
"ncfrag=OFF/LEN" where OFF is the byte offset into the message body and
LEN is the total length.

To avoid unnecessarily making printk format extended messages, Extended
netconsole is registered with printk when the first extended netconsole is
configured.

Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: David Miller <davem@davemloft.net>
Cc: Kay Sievers <kay@vrfy.org>
Cc: Petr Mladek <pmladek@suse.cz>
Cc: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-06-25 17:00:39 -07:00
Linus Torvalds 1e467e68e5 Documentation updates for 4.2
The main thing here is Ingo's big subdirectory documenting feature support
 for each architecture.  Beyond that, it's the usual pile of fixes, tweaks,
 and small additions.
 -----BEGIN PGP SIGNATURE-----
 Version: GnuPG v1
 
 iQIcBAABAgAGBQJVi0g2AAoJEI3ONVYwIuV6Me4QAIfa79z05ABSjlyWaKw46plH
 lULR9cyHdR59JVPHKjSOfT9/c+GOdoz6kkXQoe/TgVyj5fRB8seUW5GJXCASndkk
 aVd4c6yKFH1NISXsSdVQC0JbpgAURgcSR6x59It++fG3NINvXronFTWGMBHMLKcI
 A2hM2jNP914Dy5r4ipWZKzF1KxIlqK9kmLxlNoE6/LoQfBhh1dMdnyfuM11sguAy
 s5pr9JeCPbWC0RE7st/qEivXF4lpj6hd3XoYfM2Y+oukj5xEPQevLTLHOgtesnx9
 guUAul5Sw27n+Dx8I0Qxf1n+5SkrijoAa72g5vAxTs+ilOey67qba012NaYSy7RK
 s15XOIZ/1JTS9JjkO7GR5NbG6AiIIAH5P+Y501ivCIrsWciTOgKj7cOzakIEV8/P
 NX4120Lh5lbBrWeYkl8WbgMO0Me8cThbALC+rncF/wjvGyREKyxNlZ9qvBqmHYjG
 5Et2DT+rANaDmmblgMK3tX/zI1g3pN51e+CRF+Hzh1jZD3MZ/i+KS4qgfGFDzMIj
 uoniO5VfyD4zRbyv4Grg7XMpXiP8xFxKDypglYiXzzwlkarUgbMGOoFE7AkiPOKB
 t9gLPetbDsDyU/bSpzHlfObZp+q+pCxHPhyLS7hxEi3gBxYajIMbkpHHJugnE0+H
 TfkIhy6QQm1vAPTpRXaE
 =ODt8
 -----END PGP SIGNATURE-----

Merge tag 'docs-for-linus' of git://git.lwn.net/linux-2.6

Pull documentation updates from Jonathan Corbet:
 "The main thing here is Ingo's big subdirectory documenting feature
  support for each architecture.  Beyond that, it's the usual pile of
  fixes, tweaks, and small additions"

* tag 'docs-for-linus' of git://git.lwn.net/linux-2.6: (79 commits)
  doc:md: fix typo in md.txt.
  Documentation/mic/mpssd: don't build x86 userspace when cross compiling
  Documentation/prctl: don't build tsc tests when cross compiling
  Documentation/vDSO: don't build tests when cross compiling
  Doc:ABI/testing: Fix typo in sysfs-bus-fcoe
  Doc: Docbook: Change wikipedia's URL from http to https in scsi.tmpl
  Doc: Change wikipedia's URL from http to https
  Documentation/kernel-parameters: add missing pciserial to the earlyprintk
  Doc:pps: Fix typo in pps.txt
  kbuild : Fix documentation of INSTALL_HDR_PATH
  Documentation: filesystems: updated struct file_operations documentation in vfs.txt
  kbuild: edit explanation of clean-files variable
  Doc: ja_JP: Fix typo in HOWTO
  Move freefall program from Documentation/ to tools/
  Documentation: ARM: EXYNOS: Describe boot loaders interface
  Doc:nfc: Fix typo in nfc-hci.txt
  vfs: Minor documentation fix
  Doc: networking: txtimestamp: fix printf format warning
  Documentation, intel_pstate: Improve legacy mode internal governors description
  Documentation: extend use case for EXPORT_SYMBOL_GPL()
  ...
2015-06-24 20:01:36 -07:00
Masanari Iida ae13c65bc7 Doc: Change wikipedia's URL from http to https
Recently wikipedia announced to secure access to the servers.
Now all http access re-route to https.

Signed-off-by: Masanari Iida <standby24x7@gmail.com>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2015-06-22 10:14:05 -06:00
Scott Feldman b4ad7baa01 bridge: del external_learned fdbs from device on flush or ageout
We need to delete from offload the device externally learnded fdbs when any
one of these events happen:

1) Bridge ages out fdb.  (When bridge is doing ageing vs. device doing
ageing.  If device is doing ageing, it would send SWITCHDEV_FDB_DEL
directly).

2) STP state change flushes fdbs on port.

3) User uses sysfs interface to flush fdbs from bridge or bridge port:

	echo 1 >/sys/class/net/BR_DEV/bridge/flush
	echo 1 >/sys/class/net/BR_PORT/brport/flush

4) Offload driver send event SWITCHDEV_FDB_DEL to delete fdb entry.

For rocker, we can now get called to delete fdb entry in wait and nowait
contexts, so set NOWAIT flag when deleting fdb entry.

Signed-off-by: Scott Feldman <sfeldma@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-06-15 17:08:49 -07:00
David S. Miller 25c43bf13b Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2015-06-13 23:56:52 -07:00
Masanari Iida b07d496177 Doc: networking: Fix URL for wiki.wireshark.org in udplite.txt
This patch fix URL (http to https) for wiki.wireshark.org.

Signed-off-by: Masanari Iida <standby24x7@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-06-12 14:21:29 -07:00
Frans Klaver 03e8f01a67 Doc: networking: txtimestamp: fix printf format warning
Documentation/networking/timestamping/txtimestamp.c: In function ‘__print_timestamp’:
Documentation/networking/timestamping/txtimestamp.c:99:3: warning: format ‘%ld’ expects argument of type ‘long int’, but argument 3 has type ‘int64_t’ [-Wformat=]
   fprintf(stderr, "  (%+ld us)", cur_ms - prev_ms);

int64_t differs per platform, so a type specifier that differs along
with it is required.

Signed-off-by: Frans Klaver <fransklaver@gmail.com>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2015-06-05 07:59:10 +09:00
Scott Feldman 7616dcbb21 switchdev: documentation: use switchdev_port_obj_xxx for IPv4 FIB add/modify/delete ops
Clarify in documentation and code that IPV4 FIB add operation is used for
both adding a new FIB entry to the device and for modifying an existing FIB
entry on the device.

Also, remove left-over references to ipv4_fib ops and replace with details
on SWITCHDEV_PORT_IPV4_FIB object.

Signed-off-by: Scott Feldman <sfeldma@gmail.com>
Acked-by: Jiri Pirko <jiri@resnulli.us>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-06-03 23:47:23 -07:00
Scott Feldman 4b5364fbdc switchdev: documentation: for static FDB ops, use switchdev_port_fdb_xxx ops
Signed-off-by: Scott Feldman <sfeldma@gmail.com>
Acked-by: Jiri Pirko <jiri@resnulli.us>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-06-03 23:47:23 -07:00
Scott Feldman d290f1fc70 switchdev: documentation: fix grammer error
Signed-off-by: Scott Feldman <sfeldma@gmail.com>
Acked-by: Jiri Pirko <jiri@resnulli.us>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-06-03 23:47:23 -07:00
Scott Feldman f5ed2febda switchdev: documentation: fix longer-than-80-char lines
Signed-off-by: Scott Feldman <sfeldma@gmail.com>
Acked-by: Jiri Pirko <jiri@resnulli.us>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-06-03 23:47:23 -07:00
David S. Miller 9d52bf0a23 Merge branch 'for-upstream' of git://git.kernel.org/pub/scm/linux/kernel/git/bluetooth/bluetooth-next
Johan Hedberg says:

====================
pull request: bluetooth-next 2015-05-28

Here's a set of patches intended for 4.2. The majority of the changes
are on the 802.15.4 side of things rather than Bluetooth related:

 - All sorts of cleanups & fixes to ieee802154 and related drivers
 - Rework of tx power support in ieee802154 and its drivers
 - Support for setting ieee802154 tx power through nl802154
 - New IDs for the btusb driver
 - Various cleanups & smaller fixes to btusb
 - New btrtl driver for Realtec devices
 - Fix suspend/resume for Realtek devices

Please let me know if there are any issues pulling. Thanks.
====================

Signed-off-by: David S. Miller <davem@davemloft.net>
2015-05-30 23:26:45 -07:00
Eric Dumazet 07f4c90062 tcp/dccp: try to not exhaust ip_local_port_range in connect()
A long standing problem on busy servers is the tiny available TCP port
range (/proc/sys/net/ipv4/ip_local_port_range) and the default
sequential allocation of source ports in connect() system call.

If a host is having a lot of active TCP sessions, chances are
very high that all ports are in use by at least one flow,
and subsequent bind(0) attempts fail, or have to scan a big portion of
space to find a slot.

In this patch, I changed the starting point in __inet_hash_connect()
so that we try to favor even [1] ports, leaving odd ports for bind()
users.

We still perform a sequential search, so there is no guarantee, but
if connect() targets are very different, end result is we leave
more ports available to bind(), and we spread them all over the range,
lowering time for both connect() and bind() to find a slot.

This strategy only works well if /proc/sys/net/ipv4/ip_local_port_range
is even, ie if start/end values have different parity.

Therefore, default /proc/sys/net/ipv4/ip_local_port_range was changed to
32768 - 60999 (instead of 32768 - 61000)

There is no change on security aspects here, only some poor hashing
schemes could be eventually impacted by this change.

[1] : The odd/even property depends on ip_local_port_range values parity

Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-05-27 13:30:44 -04:00
Lennert Buytenhek b251d4de67 Documentation/networking/ieee802154.txt: fix various inaccuracies.
* Update the linux-zigbee git:// repository URL.

* Remove the MLME section as the current kernel does not provide a
  full 802.15.4 MLME implementation.

* The hardmac example driver 'fakehard' was removed some time ago.

* The IEEE 802.15.4 device drivers live in drivers/net/ieee802154/,
  not in drivers/ieee802154/.

* The IEEE 802.15.4 MTU is 127 bytes, not 128 bytes.

* Some of the 6LoWPAN code lives in net/6lowpan/.

Signed-off-by: Lennert Buytenhek <buytenh@wantstofly.org>
Reviewed-by: Stefan Schmidt <stefan@osg.samsung.com>
Acked-by: Alexander Aring <alex.aring@gmail.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
2015-05-26 20:25:58 +02:00
Jesper Dangaard Brouer 282fb58947 pktgen: add sample script pktgen_sample02_multiqueue.sh
Add the pktgen samples script pktgen_sample02_multiqueue.sh that
demonstrates generating packets on multiqueue NICs.

Specifically notice the options "-t" that specifies how many
kernel threads to activate.  Also notice the flag QUEUE_MAP_CPU,
which cause the SKB TX queue to be mapped to the CPU running the
kernel thread.  For best scalability people are also encourage to
map NIC IRQ /proc/irq/*/smp_affinity to CPU number.

Usage example with "-t" 4 threads and help:
 ./pktgen_sample02_multiqueue.sh -i eth4 -m 00:1B:21:3C:9D:F8 -t 4

Usage: ./pktgen_sample02_multiqueue.sh [-vx] -i ethX
  -i : ($DEV)       output interface/device (required)
  -s : ($PKT_SIZE)  packet size
  -d : ($DEST_IP)   destination IP
  -m : ($DST_MAC)   destination MAC-addr
  -t : ($THREADS)   threads to start
  -c : ($SKB_CLONE) SKB clones send before alloc new SKB
  -b : ($BURST)     HW level bursting of SKBs
  -v : ($VERBOSE)   verbose
  -x : ($DEBUG)     debug

Removing pktgen.conf-2-1 and pktgen.conf-2-2 as these examples
should be covered now.

Signed-off-by: Jesper Dangaard Brouer <brouer@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-05-22 23:59:17 -04:00
Jesper Dangaard Brouer 6f09479758 pktgen: add sample script pktgen_sample01_simple.sh
Add the first basic pktgen samples script pktgen_sample01_simple.sh,
which demonstrates the a simple use of the helper functions.
Removing pktgen.conf-1-1 as that example should be covered now.

The naming scheme pktgen_sampleNN, where NN is a number, should encourage
reading the samples in a specific order.

Script cause pktgen sending with a single thread and single interface,
and introduce flow variation via random UDP source port.

Usage example and help:
 ./pktgen_sample01_simple.sh -i eth4 -m 00:1B:21:3C:9D:F8 -d 192.168.8.2

Usage: ./pktgen_sample01_simple.sh [-vx] -i ethX
  -i : ($DEV)       output interface/device (required)
  -s : ($PKT_SIZE)  packet size
  -d : ($DEST_IP)   destination IP
  -m : ($DST_MAC)   destination MAC-addr
  -c : ($SKB_CLONE) SKB clones send before alloc new SKB
  -v : ($VERBOSE)   verbose
  -x : ($DEBUG)     debug

Signed-off-by: Jesper Dangaard Brouer <brouer@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-05-22 23:59:17 -04:00
Jesper Dangaard Brouer 2a1ddf27e8 pktgen: document ability to add same device to several threads
The pktgen.txt documentation still claimed that adding same device to
multiple threads were not supported, but it have been since 2008 via
commit e6fce5b916 ("pktgen: multiqueue etc.").

Document this and describe the naming scheme dev@X, as the procfile name
still need to be unique.

Fixes: e6fce5b916 ("pktgen: multiqueue etc.")
Signed-off-by: Jesper Dangaard Brouer <brouer@redhat.com>
Acked-by: Alexei Starovoitov <ast@plumgrid.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-05-22 23:59:16 -04:00
Jesper Dangaard Brouer 91db4b3c89 pktgen: doc were missing several config options
The pktgen.txt documentation over available config options were not complete.
Making the list complete by adding the following.

Pgcontrol commands:
 reset

Device commands:
 burst
 queue_map_min
 queue_map_max
 skb_priority
 tos
 traffic_class
 node
 spi
 dst6_max
 dst6_min
 vlan_cfi
 vlan_id
 vlan_p
 svlan_cfi
 svlan_id
 svlan_p

Signed-off-by: Jesper Dangaard Brouer <brouer@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-05-22 23:59:16 -04:00
Jesper Dangaard Brouer d012827e81 pktgen: remove obsolete "max_before_softirq" from pktgen doc
And cleanup some whitespaces in pktgen.txt.

Signed-off-by: Jesper Dangaard Brouer <brouer@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-05-22 23:59:16 -04:00
Daniel Borkmann 492135557d tcp: add rfc3168, section 6.1.1.1. fallback
This work as a follow-up of commit f7b3bec6f5 ("net: allow setting ecn
via routing table") and adds RFC3168 section 6.1.1.1. fallback for outgoing
ECN connections. In other words, this work adds a retry with a non-ECN
setup SYN packet, as suggested from the RFC on the first timeout:

  [...] A host that receives no reply to an ECN-setup SYN within the
  normal SYN retransmission timeout interval MAY resend the SYN and
  any subsequent SYN retransmissions with CWR and ECE cleared. [...]

Schematic client-side view when assuming the server is in tcp_ecn=2 mode,
that is, Linux default since 2009 via commit 255cac91c3 ("tcp: extend
ECN sysctl to allow server-side only ECN"):

 1) Normal ECN-capable path:

    SYN ECE CWR ----->
                <----- SYN ACK ECE
            ACK ----->

 2) Path with broken middlebox, when client has fallback:

    SYN ECE CWR ----X crappy middlebox drops packet
                      (timeout, rtx)
            SYN ----->
                <----- SYN ACK
            ACK ----->

In case we would not have the fallback implemented, the middlebox drop
point would basically end up as:

    SYN ECE CWR ----X crappy middlebox drops packet
                      (timeout, rtx)
    SYN ECE CWR ----X crappy middlebox drops packet
                      (timeout, rtx)
    SYN ECE CWR ----X crappy middlebox drops packet
                      (timeout, rtx)

In any case, it's rather a smaller percentage of sites where there would
occur such additional setup latency: it was found in end of 2014 that ~56%
of IPv4 and 65% of IPv6 servers of Alexa 1 million list would negotiate
ECN (aka tcp_ecn=2 default), 0.42% of these webservers will fail to connect
when trying to negotiate with ECN (tcp_ecn=1) due to timeouts, which the
fallback would mitigate with a slight latency trade-off. Recent related
paper on this topic:

  Brian Trammell, Mirja Kühlewind, Damiano Boppart, Iain Learmonth,
  Gorry Fairhurst, and Richard Scheffenegger:
    "Enabling Internet-Wide Deployment of Explicit Congestion Notification."
    Proc. PAM 2015, New York.
  http://ecn.ethz.ch/ecn-pam15.pdf

Thus, when net.ipv4.tcp_ecn=1 is being set, the patch will perform RFC3168,
section 6.1.1.1. fallback on timeout. For users explicitly not wanting this
which can be in DC use case, we add a net.ipv4.tcp_ecn_fallback knob that
allows for disabling the fallback.

tp->ecn_flags are not being cleared in tcp_ecn_clear_syn() on output, but
rather we let tcp_ecn_rcv_synack() take that over on input path in case a
SYN ACK ECE was delayed. Thus a spurious SYN retransmission will not prevent
ECN being negotiated eventually in that case.

Reference: https://www.ietf.org/proceedings/92/slides/slides-92-iccrg-1.pdf
Reference: https://www.ietf.org/proceedings/89/slides/slides-89-tsvarea-1.pdf
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Mirja Kühlewind <mirja.kuehlewind@tik.ee.ethz.ch>
Signed-off-by: Brian Trammell <trammell@tik.ee.ethz.ch>
Cc: Eric Dumazet <edumazet@google.com>
Cc: Dave That <dave.taht@gmail.com>
Acked-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-05-19 16:53:37 -04:00
Florian Westphal e578d9c025 net: sched: use counter to break reclassify loops
Seems all we want here is to avoid endless 'goto reclassify' loop.
tc_classify_compat even resets this counter when something other
than TC_ACT_RECLASSIFY is returned, so this skb-counter doesn't
break hypothetical loops induced by something other than perpetual
TC_ACT_RECLASSIFY return values.

skb_act_clone is now identical to skb_clone, so just use that.

Tested with following (bogus) filter:
tc filter add dev eth0 parent ffff: \
 protocol ip u32 match u32 0 0 police rate 10Kbit burst \
 64000 mtu 1500 action reclassify

Acked-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: Florian Westphal <fw@strlen.de>
Acked-by: Alexei Starovoitov <ast@plumgrid.com>
Acked-by: Jamal Hadi Salim <jhs@mojatatu.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-05-13 15:08:14 -04:00
Scott Feldman 1f5dc44c88 switchdev: apply review comments on documentation
There were a few review comments on the switchdev.txt documentation that
didn't get included with the Spring Cleanup series, so include them now.

Signed-off-by: Scott Feldman <sfeldma@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-05-13 12:26:28 -04:00
Scott Feldman 4ceec22d6d switchdev: bring documentation up-to-date
Much need updated of switchdev documentation to cover what's been
implmented to-date.  There are some XXX comments in the text for
unimplemented or broken items.  I'd like to keep these in there (poor-man's
TODO list) and update the document once each issue is resolved.

Signed-off-by: Scott Feldman <sfeldma@gmail.com>
Acked-by: Jiri Pirko <jiri@resnulli.us>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-05-12 18:43:56 -04:00
Mahesh Bandewar d22a5fc0c3 bonding: Implement user key part of port_key in an AD system.
The port key has three components - user-key, speed-part, and duplex-part.
The LSBit is for the duplex-part, next 5 bits are for the speed while the
remaining 10 bits are the user defined key bits. Get these 10 bits
from the user-space (through the SysFs interface) and use it to form the
admin port-key. Allowed range for the user-key is 0 - 1023 (10 bits). If
it is not provided then use zero for the user-key-bits (default).

It can set using following example code -

   # modprobe bonding mode=4
   # usr_port_key=$(( RANDOM & 0x3FF ))
   # echo $usr_port_key > /sys/class/net/bond0/bonding/ad_user_port_key
   # echo +eth1 > /sys/class/net/bond0/bonding/slaves
   ...
   # ip link set bond0 up

Signed-off-by: Mahesh Bandewar <maheshb@google.com>
Reviewed-by: Nikolay Aleksandrov <nikolay@redhat.com>
[jt: * fixed up style issues reported by checkpatch
     * fixed up context from change in ad_actor_sys_prio patch]
Signed-off-by: Jonathan Toppins <jtoppins@cumulusnetworks.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-05-11 10:59:32 -04:00
Mahesh Bandewar 7451495755 bonding: Allow userspace to set actors' macaddr in an AD-system.
In an AD system, the communication between actor and partner is the
business between these two entities. In the current setup anyone on the
same L2 can "guess" the LACPDU contents and then possibly send the
spoofed LACPDUs and trick the partner causing connectivity issues for
the AD system. This patch allows to use a random mac-address obscuring
it's identity making it harder for someone in the L2 is do the same thing.

This patch allows user-space to choose the mac-address for the AD-system.
This mac-address can not be NULL or a Multicast. If the mac-address is set
from user-space; kernel will honor it and will not overwrite it. In the
absence (value from user space); the logic will default to using the
masters' mac as the mac-address for the AD-system.

It can be set using example code below -

   # modprobe bonding mode=4
   # sys_mac_addr=$(printf '%02x:%02x:%02x:%02x:%02x:%02x' \
                    $(( (RANDOM & 0xFE) | 0x02 )) \
                    $(( RANDOM & 0xFF )) \
                    $(( RANDOM & 0xFF )) \
                    $(( RANDOM & 0xFF )) \
                    $(( RANDOM & 0xFF )) \
                    $(( RANDOM & 0xFF )))
   # echo $sys_mac_addr > /sys/class/net/bond0/bonding/ad_actor_system
   # echo +eth1 > /sys/class/net/bond0/bonding/slaves
   ...
   # ip link set bond0 up

Signed-off-by: Mahesh Bandewar <maheshb@google.com>
Reviewed-by: Nikolay Aleksandrov <nikolay@redhat.com>
[jt: fixed up style issues reported by checkpatch]
Signed-off-by: Jonathan Toppins <jtoppins@cumulusnetworks.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-05-11 10:59:32 -04:00
Mahesh Bandewar 6791e4661c bonding: Allow userspace to set actors' system_priority in AD system
This patch allows user to randomize the system-priority in an ad-system.
The allowed range is 1 - 0xFFFF while default value is 0xFFFF. If user
does not specify this value, the system defaults to 0xFFFF, which is
what it was before this patch.

Following example code could set the value -
    # modprobe bonding mode=4
    # sys_prio=$(( 1 + RANDOM + RANDOM ))
    # echo $sys_prio > /sys/class/net/bond0/bonding/ad_actor_sys_prio
    # echo +eth1 > /sys/class/net/bond0/bonding/slaves
    ...
    # ip link set bond0 up

Signed-off-by: Mahesh Bandewar <maheshb@google.com>
Reviewed-by: Nikolay Aleksandrov <nikolay@redhat.com>
[jt: * fixed up style issues reported by checkpatch
     * changed how the default value is set in bond_check_params(), this
       makes the default consistent between what gets set for a new bond
       and what the default is claimed to be in the bonding options.]
Signed-off-by: Jonathan Toppins <jtoppins@cumulusnetworks.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-05-11 10:59:31 -04:00
Alexei Starovoitov 62f64aed62 pktgen: introduce xmit_mode '<start_xmit|netif_receive>'
Introduce xmit_mode 'netif_receive' for pktgen which generates the
packets using familiar pktgen commands, but feeds them into
netif_receive_skb() instead of ndo_start_xmit().

Default mode is called 'start_xmit'.

It is designed to test netif_receive_skb and ingress qdisc
performace only. Make sure to understand how it works before
using it for other rx benchmarking.

Sample script 'pktgen.sh':
\#!/bin/bash
function pgset() {
  local result

  echo $1 > $PGDEV

  result=`cat $PGDEV | fgrep "Result: OK:"`
  if [ "$result" = "" ]; then
    cat $PGDEV | fgrep Result:
  fi
}

[ -z "$1" ] && echo "Usage: $0 DEV" && exit 1
ETH=$1

PGDEV=/proc/net/pktgen/kpktgend_0
pgset "rem_device_all"
pgset "add_device $ETH"

PGDEV=/proc/net/pktgen/$ETH
pgset "xmit_mode netif_receive"
pgset "pkt_size 60"
pgset "dst 198.18.0.1"
pgset "dst_mac 90:e2:ba:ff:ff:ff"
pgset "count 10000000"
pgset "burst 32"

PGDEV=/proc/net/pktgen/pgctrl
echo "Running... ctrl^C to stop"
pgset "start"
echo "Done"
cat /proc/net/pktgen/$ETH

Usage:
$ sudo ./pktgen.sh eth2
...
Result: OK: 232376(c232372+d3) usec, 10000000 (60byte,0frags)
  43033682pps 20656Mb/sec (20656167360bps) errors: 10000000

Raw netif_receive_skb speed should be ~43 million packet
per second on 3.7Ghz x86 and 'perf report' should look like:
  37.69%  kpktgend_0   [kernel.vmlinux]  [k] __netif_receive_skb_core
  25.81%  kpktgend_0   [kernel.vmlinux]  [k] kfree_skb
   7.22%  kpktgend_0   [kernel.vmlinux]  [k] ip_rcv
   5.68%  kpktgend_0   [pktgen]          [k] pktgen_thread_worker

If fib_table_lookup is seen on top, it means skb was processed
by the stack. To benchmark netif_receive_skb only make sure
that 'dst_mac' of your pktgen script is different from
receiving device mac and it will be dropped by ip_rcv

Signed-off-by: Alexei Starovoitov <ast@plumgrid.com>
Signed-off-by: Jesper Dangaard Brouer <brouer@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-05-09 22:26:06 -04:00
Jesper Dangaard Brouer f1f00d8ff6 pktgen: adjust flag NO_TIMESTAMP to be more pktgen compliant
Allow flag NO_TIMESTAMP to turn timestamping on again, like other flags,
with a negation of the flag like !NO_TIMESTAMP.

Also document the option flag NO_TIMESTAMP.

Fixes: afb84b6261 ("pktgen: add flag NO_TIMESTAMP to disable timestamping")
Signed-off-by: Jesper Dangaard Brouer <brouer@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-05-09 22:26:06 -04:00
Shawn Landden a2f1183599 can.h: make padding given by gcc explicit
The current definition of struct can_frame has a 16-byte size, with 8-byte
alignment, but the 3 bytes of padding are not explicit like the similar 2 bytes
of padding of struct canfd_frame. Make it explicit so it is easier to read.

Signed-off-by: Shawn Landden <shawn@churchofgit.com>
Acked-by: Oliver Hartkopp <socketcan@hartkopp.net>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
2015-05-06 08:03:19 +02:00
Tom Herbert 82a584b7cd ipv6: Flow label state ranges
This patch divides the IPv6 flow label space into two ranges:
0-7ffff is reserved for flow label manager, 80000-fffff will be
used for creating auto flow labels (per RFC6438). This only affects how
labels are set on transmit, it does not affect receive. This range split
can be disbaled by systcl.

Background:

IPv6 flow labels have been an unmitigated disappointment thus far
in the lifetime of IPv6. Support in HW devices to use them for ECMP
is lacking, and OSes don't turn them on by default. If we had these
we could get much better hashing in IPv6 networks without resorting
to DPI, possibly eliminating some of the motivations to to define new
encaps in UDP just for getting ECMP.

Unfortunately, the initial specfications of IPv6 did not clarify
how they are to be used. There has always been a vague concept that
these can be used for ECMP, flow hashing, etc. and we do now have a
good standard how to this in RFC6438. The problem is that flow labels
can be either stateful or stateless (as in RFC6438), and we are
presented with the possibility that a stateless label may collide
with a stateful one.  Attempts to split the flow label space were
rejected in IETF. When we added support in Linux for RFC6438, we
could not turn on flow labels by default due to this conflict.

This patch splits the flow label space and should give us
a path to enabling auto flow labels by default for all IPv6 packets.
This is an API change so we need to consider compatibility with
existing deployment. The stateful range is chosen to be the lower
values in hopes that most uses would have chosen small numbers.

Once we resolve the stateless/stateful issue, we can proceed to
look at enabling RFC6438 flow labels by default (starting with
scaled testing).

Signed-off-by: Tom Herbert <tom@herbertland.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-05-03 21:58:01 -04:00
Florian Westphal 4749c3ef85 net: sched: remove TC_MUNGED bits
Not used.

pedit sets TC_MUNGED when packet content was altered, but all the core
does is unset MUNGED again and then set OK2MUNGE.

And the latter isn't tested anywhere. So lets remove both
TC_MUNGED and TC_OK2MUNGE.

Signed-off-by: Florian Westphal <fw@strlen.de>
Acked-by: Alexei Starovoitov <ast@plumgrid.com>
Acked-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Jamal Hadi Salim <jhs@mojatatu.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-05-02 22:25:17 -04:00
Eric Dumazet a31196b07f net: rfs: fix crash in get_rps_cpus()
Commit 567e4b7973 ("net: rfs: add hash collision detection") had one
mistake :

RPS_NO_CPU is no longer the marker for invalid cpu in set_rps_cpu()
and get_rps_cpu(), as @next_cpu was the result of an AND with
rps_cpu_mask

This bug showed up on a host with 72 cpus :
next_cpu was 0x7f, and the code was trying to access percpu data of an
non existent cpu.

In a follow up patch, we might get rid of compares against nr_cpu_ids,
if we init the tables with 0. This is silly to test for a very unlikely
condition that exists only shortly after table initialization, as
we got rid of rps_reset_sock_flow() and similar functions that were
writing this RPS_NO_CPU magic value at flow dismantle : When table is
old enough, it never contains this value anymore.

Fixes: 567e4b7973 ("net: rfs: add hash collision detection")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: Tom Herbert <tom@herbertland.com>
Cc: Ben Hutchings <ben@decadent.org.uk>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-04-26 16:07:57 -04:00
Robert Shearman 37bde79979 mpls: Per-device enabling of packet input
An MPLS network is a single trust domain where the edges must be in
control of what labels make their way into the core. The simplest way
of ensuring this is for the edge device to always impose the labels,
and not allow forward labeled traffic from untrusted neighbours. This
is achieved by allowing a per-device configuration of whether MPLS
traffic input from that interface should be processed or not.

To be secure by default, the default state is changed to MPLS being
disabled on all interfaces unless explicitly enabled and no global
option is provided to change the default. Whilst this differs from
other protocols (e.g. IPv6), network operators are used to explicitly
enabling MPLS forwarding on interfaces, and with the number of links
to the MPLS core typically fairly low this doesn't present too much of
a burden on operators.

Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: Robert Shearman <rshearma@brocade.com>
Reviewed-by: "Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-04-22 14:24:54 -04:00
David S. Miller 87ffabb1f0 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
The dwmac-socfpga.c conflict was a case of a bug fix overlapping
changes in net-next to handle an error pointer differently.

Signed-off-by: David S. Miller <davem@davemloft.net>
2015-04-14 15:44:14 -04:00
Stephen Hemminger 322d3ed167 ixgb: remove references to ifconfig
Move documentation into this century, even if this device hasn't
been available for some time.

Signed-off-by: Stephen Hemminger <stephen@networkplumber.org>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>
2015-04-09 22:04:04 -07:00
Stephen Hemminger d7018be0ae ixgbe: fix documentation
The MTU values in the documentation do not match the source.
The source has frame limit of IXGBE_MAX_JUMBO_FRAME_SIZE (9728)
which is MTU of 9710 because of the accounting for Ethernet header
and CRC.

Also, don't refer to the obsolete ifconfig command.

Signed-off-by: Stephen Hemminger <stephen@networkplumber.org>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>
2015-04-09 22:03:54 -07:00
Stephen Hemminger c0a34ebd43 igb: doc don't refer to ifconfig
ifconfig command is obsolete, best to remove all references so that
new users learn ip.

Signed-off-by: Stephen Hemminger <stephen@networkplumber.org>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>
2015-04-09 22:03:20 -07:00
Sowmini Varadhan ebe96e641d RDS: Documentation: Document AF_RDS, PF_RDS and SOL_RDS correctly.
AF_RDS, PF_RDS and SOL_RDS are available in header files,
and there is no need to get their values from /proc. Document
this correctly.

Fixes: 0c5f9b8830 ("RDS: Documentation")

Signed-off-by: Sowmini Varadhan <sowmini.varadhan@oracle.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-04-08 15:17:04 -04:00
Oliver Hartkopp a5581ef4c2 can: introduce new raw socket option to join the given CAN filters
The CAN_RAW socket can set multiple CAN identifier specific filters that lead
to multiple filters in the af_can.c filter processing. These filters are
indenpendent from each other which leads to logical OR'ed filters when applied.

This socket option joines the given CAN filters in the way that only CAN frames
are passed to user space that matched *all* given CAN filters. The semantic for
the applied filters is therefore changed to a logical AND.

This is useful especially when the filterset is a combination of filters where
the CAN_INV_FILTER flag is set in order to notch single CAN IDs or CAN ID
ranges from the incoming traffic.

As the raw_rcv() function is executed from NET_RX softirq the introduced
variables are implemented as per-CPU variables to avoid extensive locking at
CAN frame reception time.

Signed-off-by: Oliver Hartkopp <socketcan@hartkopp.net>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
2015-04-01 11:28:22 +02:00
Michal Sekletar 27cd545247 filter: introduce SKF_AD_VLAN_TPID BPF extension
If vlan offloading takes place then vlan header is removed from frame
and its contents, both vlan_tci and vlan_proto, is available to user
space via TPACKET interface. However, only vlan_tci can be used in BPF
filters.

This commit introduces a new BPF extension. It makes possible to load
the value of vlan_proto (vlan TPID) to register A. Support for classic
BPF and eBPF is being added, analogous to skb->protocol.

Cc: Daniel Borkmann <daniel@iogearbox.net>
Cc: Alexei Starovoitov <ast@plumgrid.com>
Cc: Jiri Pirko <jpirko@redhat.com>

Signed-off-by: Michal Sekletar <msekleta@redhat.com>
Acked-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Alexei Starovoitov <ast@plumgrid.com>
Reviewed-by: Jiri Pirko <jiri@resnulli.us>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-03-24 15:25:15 -04:00
Hannes Frederic Sowa 9f0761c154 ipv6: add documentation for stable_secret, idgen_delay and idgen_retries knobs
Cc: Erik Kline <ek@google.com>
Cc: Fernando Gont <fgont@si6networks.com>
Cc: Lorenzo Colitti <lorenzo@google.com>
Cc: YOSHIFUJI Hideaki/吉藤英明 <hideaki.yoshifuji@miraclelinux.com>
Signed-off-by: Hannes Frederic Sowa <hannes@stressinduktion.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-03-23 22:12:09 -04:00
Alexander Drozdov 682f048bd4 af_packet: pass checksum validation status to the user
Introduce TP_STATUS_CSUM_VALID tp_status flag to tell the
af_packet user that at least the transport header checksum
has been already validated.

For now, the flag may be set for incoming packets only.

Signed-off-by: Alexander Drozdov <al.drozdov@gmail.com>
Cc: Willem de Bruijn <willemb@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-03-23 22:01:28 -04:00
YOSHIFUJI Hideaki/吉藤英明 89c69d3ce5 net: neighbour: Document {mcast, ucast}_solicit, mcast_resolicit.
Signed-off-by: YOSHIFUJI Hideaki <hideaki.yoshifuji@miraclelinux.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-03-20 21:47:40 -04:00
John Fastabend 822b3b2ebf net: Add max rate tx queue attribute
This adds a tx_maxrate attribute to the tx queue sysfs entry allowing
for max-rate limiting. Along with DCB-ETS and BQL this provides another
knob to tune queue performance. The limit units are Mbps.

By default it is disabled. To disable the rate limitation after it
has been set for a queue, it should be set to zero.

Signed-off-by: John Fastabend <john.r.fastabend@intel.com>
Signed-off-by: Or Gerlitz <ogerlitz@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-03-18 14:55:18 -04:00
stephen hemminger 008a5b07f1 neterion: remove reference to ifconfig
Remove reference to obsolete ifconfig command.
MTU can be changed with ip command instead.

Signed-off-by: Stephen Hemminger <stephen@networkplumber.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-03-08 19:11:44 -04:00
Fan Du fab4276084 ipv4: Documenting two sysctls for tcp PMTU probe
Namely tcp_probe_interval to control how often to restart
a probe. And tcp_probe_threshold to control when stop the
probing in respect to the width of search range in bytes

Signed-off-by: Fan Du <fan.du@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-03-06 14:57:42 -05:00
Eric W. Biederman 7720c01f3f mpls: Add a sysctl to control the size of the mpls label table
This sysctl gives two benefits.  By defaulting the table size to 0
mpls even when compiled in and enabled defaults to not forwarding
any packets.  This prevents unpleasant surprises for users.

The other benefit is that as mpls labels are allocated locally a dense
table a small dense label table may be used which saves memory and
is extremely simple and efficient to implement.

This sysctl allows userspace to choose the restrictions on the label
table size userspace applications need to cope with.

Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-03-04 00:26:06 -05:00
David S. Miller 77f0379fa8 Merge git://git.kernel.org/pub/scm/linux/kernel/git/pablo/nf-next
Pablo Neira Ayuso says:

====================
Netfilter updates for net-next

A small batch with accumulated updates in nf-next, mostly IPVS updates,
they are:

1) Add 64-bits stats counters to IPVS, from Julian Anastasov.

2) Move NETFILTER_XT_MATCH_ADDRTYPE out of NETFILTER_ADVANCED as docker
seem to require this, from Anton Blanchard.

3) Use boolean instead of numeric value in set_match_v*(), from
coccinelle via Fengguang Wu.

4) Allows rescheduling of new connections in IPVS when port reuse is
detected, from Marcelo Ricardo Leitner.

5) Add missing bits to support arptables extensions from nft_compat,
from Arturo Borrero.

Patrick is preparing a large batch to enhance the set infrastructure,
named expressions among other things, that should follow up soon after
this batch.
====================

Signed-off-by: David S. Miller <davem@davemloft.net>
2015-03-02 14:55:05 -05:00
Marcelo Ricardo Leitner d752c36457 ipvs: allow rescheduling of new connections when port reuse is detected
Currently, when TCP/SCTP port reusing happens, IPVS will find the old
entry and use it for the new one, behaving like a forced persistence.
But if you consider a cluster with a heavy load of small connections,
such reuse will happen often and may lead to a not optimal load
balancing and might prevent a new node from getting a fair load.

This patch introduces a new sysctl, conn_reuse_mode, that allows
controlling how to proceed when port reuse is detected. The default
value will allow rescheduling of new connections only if the old entry
was in TIME_WAIT state for TCP or CLOSED for SCTP.

Signed-off-by: Marcelo Ricardo Leitner <mleitner@redhat.com>
Signed-off-by: Julian Anastasov <ja@ssi.bg>
Signed-off-by: Simon Horman <horms@verge.net.au>
2015-02-25 13:46:35 +09:00
Ben Hutchings 4e081e0cbd pktgen: Correct documentation of module name and command
Drop the '.o' suffix so this text properly covers both the
built-in and modular cases.

'insmod pktgen' obviously won't work; the command should be modprobe.

Signed-off-by: Ben Hutchings <ben.hutchings@codethink.co.uk>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-02-23 22:04:25 -05:00
Ben Hutchings 7c95a9d962 samples/pktgen: Add sample scripts for pktgen facility
These are Robert Olsson's samples which used to be available from
<ftp://robur.slu.se/pub/Linux/net-development/pktgen-testing/examples/>
but currently are not.

Change the documentation to refer to these consistently as 'sample
scripts', matching the directory name used here.

Cc: Robert Olsson <robert@herjulf.se>
Signed-off-by: Ben Hutchings <ben.hutchings@codethink.co.uk>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-02-23 22:03:18 -05:00
Ben Hutchings ca5b542cce pktgen: Fix grammar errors and some poor wording in documentation
Thanks to Rob Jones for suggesting some of the changes.

Cc: Rob Jones <rob.jones@codethink.co.uk>
Signed-off-by: Ben Hutchings <ben.hutchings@codethink.co.uk>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-02-23 22:03:18 -05:00
Ben Hutchings 98e688f405 pktgen: Delete the original date from documentation
This has been updated quite a few times since 2004, and git can
keep track of the actual date for us.

Signed-off-by: Ben Hutchings <ben.hutchings@codethink.co.uk>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-02-23 22:03:18 -05:00
Linus Torvalds 73b4f63aeb Documentation changes for 3.20
Highlights this time around include:
 
  - A thrashing of SubmittingPatches to bring it out of the "send everything
    to Linus" era of kernel development.
 
  - A new document on completions from Nicholas McGuire
 
  - Lots of typo fixes, formatting improvements, corrections, build fixes,
    and more.
 -----BEGIN PGP SIGNATURE-----
 Version: GnuPG v1
 
 iQIcBAABAgAGBQJU2QvPAAoJEI3ONVYwIuV6UdAP/iFa3yK0jTMFJV49K2PhVPiW
 9AxlcDT3mKCmGrCxS2ST84Kyvxi+bn5k6pQbOhXqPTLRzlWj7o+9zG76yCvhI1/0
 mSUc/DoEZSlxQCAi4RH6lNFBtyopwOF1Fy2hqP8Wj7fOu2OxJ+DbTFJ7Cjy2Ybnq
 REFT+28mD3GwBYv1r6mirbXsxBGUWK4avqUl9TPkC1AgVoksZ/aLrDffdmixL6Ul
 cNBGGn3/mQhDCd6QgrHfdSe3BmL/vpiO5nr7BnSGe/hg65tUgi5d5s9tyP1eRkYo
 d+3Ityz24ISCW6kAGH9udNzdtw2QA7vxdVIcz01RgxHQcYdcTyE7ZH28+A+aEtxm
 ANkOO5PvaQJrCdPATOuVvwTPmK+xjdW7TmmPiJZ3QpVuPkFlUDP+amOgOajBDQ2l
 UDHE2GfrUcjUG4FSUGXLVKXVAXuqLG8DG1rMSEf1utb80jxcuhK2kIrhjfRi4gle
 gL3PKd7SfhMowm3QbaMxdiy0RpNK+IlJpiFsDFWUJwQCJvCtxlwL/RalfGxitjqs
 RxJo+uPxFLrmsnM8fdw5a/82R0T/nclvnzniq5PoZROOJ6VzKvwn3oS9d63bliPI
 JQTfNpbfYq8sRlrPlp+XETrrcbmmYyxgqvurLobNXb74cdJHEzHjqf9OG++NKtQQ
 Jre067cSnkSrHAHtxNns
 =r07E
 -----END PGP SIGNATURE-----

Merge tag 'docs-for-linus' of git://git.lwn.net/linux-2.6

Pull documentation updates from Jonathan Corbet:
 "Highlights this time around include:

   - A thrashing of SubmittingPatches to bring it out of the "send
     everything to Linus" era of kernel development.

   - A new document on completions from Nicholas McGuire

   - Lots of typo fixes, formatting improvements, corrections, build
     fixes, and more"

* tag 'docs-for-linus' of git://git.lwn.net/linux-2.6: (35 commits)
  Documentation: Fix the wrong command `echo -1 > set_ftrace_pid` for cleaning the filter.
  can-doc: Fixed a wrong filepath in can.txt
  Documentation: Fix trivial typo in comment.
  kgdb,docs: Fix typo and minor style issues
  Documentation: add description for FTRACE probe status
  doc: brief user documentation for completion
  Documentation/misc-devices/mei: Fix indentation of embedded code.
  Documentation/misc-devices/mei: Fix indentation of enumeration.
  Documentation/misc-devices/mei: Fix spacing around parentheses.
  Documentation/misc-devices/mei: Fix formatting of headings.
  Documentation: devicetree: Fix double words in Doumentation/devicetree
  Documentation: mm: Fix typo in vm.txt
  lockstat: Add documentation on contention and contenting points
  Documentation: fix blackfin gptimers-example build errors
  Fixes column alignment in table of contents entry 1.9 in Documentation/filesystems/proc.txt
  CodingStyle: enable emacs display of trailing whitespace
  DocBook: Do not exceed argument list limit
  gpio: board.txt: Fix the gpio name example
  Documentation/SubmittingPatches: unify whitespace/tabs for the DCO
  MAINTAINERS: Add the docs-next git tree to the maintainer entry
  ...
2015-02-11 13:03:11 -08:00
Neal Cardwell 032ee42369 tcp: helpers to mitigate ACK loops by rate-limiting out-of-window dupacks
Helpers for mitigating ACK loops by rate-limiting dupacks sent in
response to incoming out-of-window packets.

This patch includes:

- rate-limiting logic
- sysctl to control how often we allow dupacks to out-of-window packets
- SNMP counter for cases where we rate-limited our dupack sending

The rate-limiting logic in this patch decides to not send dupacks in
response to out-of-window segments if (a) they are SYNs or pure ACKs
and (b) the remote endpoint is sending them faster than the configured
rate limit.

We rate-limit our responses rather than blocking them entirely or
resetting the connection, because legitimate connections can rely on
dupacks in response to some out-of-window segments. For example, zero
window probes are typically sent with a sequence number that is below
the current window, and ZWPs thus expect to thus elicit a dupack in
response.

We allow dupacks in response to TCP segments with data, because these
may be spurious retransmissions for which the remote endpoint wants to
receive DSACKs. This is safe because segments with data can't
realistically be part of ACK loops, which by their nature consist of
each side sending pure/data-less ACKs to each other.

The dupack interval is controlled by a new sysctl knob,
tcp_invalid_ratelimit, given in milliseconds, in case an administrator
needs to dial this upward in the face of a high-rate DoS attack. The
name and units are chosen to be analogous to the existing analogous
knob for ICMP, icmp_ratelimit.

The default value for tcp_invalid_ratelimit is 500ms, which allows at
most one such dupack per 500ms. This is chosen to be 2x faster than
the 1-second minimum RTO interval allowed by RFC 6298 (section 2, rule
2.4). We allow the extra 2x factor because network delay variations
can cause packets sent at 1 second intervals to be compressed and
arrive much closer.

Reported-by: Avery Fay <avery@mixpanel.com>
Signed-off-by: Neal Cardwell <ncardwell@google.com>
Signed-off-by: Yuchung Cheng <ycheng@google.com>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-02-08 01:03:12 -08:00
David S. Miller 6e03f896b5 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
Conflicts:
	drivers/net/vxlan.c
	drivers/vhost/net.c
	include/linux/if_vlan.h
	net/core/dev.c

The net/core/dev.c conflict was the overlap of one commit marking an
existing function static whilst another was adding a new function.

In the include/linux/if_vlan.h case, the type used for a local
variable was changed in 'net', whereas the function got rewritten
to fix a stacked vlan bug in 'net-next'.

In drivers/vhost/net.c, Al Viro's iov_iter conversions in 'net-next'
overlapped with an endainness fix for VHOST 1.0 in 'net'.

In drivers/net/vxlan.c, vxlan_find_vni() added a 'flags' parameter
in 'net-next' whereas in 'net' there was a bug fix to pass in the
correct network namespace pointer in calls to this function.

Signed-off-by: David S. Miller <davem@davemloft.net>
2015-02-05 14:33:28 -08:00
Stefan Tatschner 67c47cfcc7 can-doc: Fixed a wrong filepath in can.txt
<linux/can/error.h> moved in the big UAPI shuffle; update the document to
note its new location.

Signed-off-by: Stefan Tatschner <stefan@sevenbyte.org>
[jc: added changelog]
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2015-02-05 09:59:44 -05:00
Richard Weinberger e6b02be81b Documentation: Update netlink_mmap.txt
Update netlink_mmap.txt wrt. commit 4682a03586
("netlink: Always copy on mmap TX.").

Signed-off-by: Richard Weinberger <richard@nod.at>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-02-02 18:50:00 -08:00
Willem de Bruijn 2368592365 net-timestamp: no-payload option in txtimestamp test
Demonstrate how SOF_TIMESTAMPING_OPT_TSONLY can be used and
test the implementation.

Signed-off-by: Willem de Bruijn <willemb@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-02-02 18:46:51 -08:00
Willem de Bruijn 49ca0d8bfa net-timestamp: no-payload option
Add timestamping option SOF_TIMESTAMPING_OPT_TSONLY. For transmit
timestamps, this loops timestamps on top of empty packets.

Doing so reduces the pressure on SO_RCVBUF. Payload inspection and
cmsg reception (aside from timestamps) are no longer possible. This
works together with a follow on patch that allows administrators to
only allow tx timestamping if it does not loop payload or metadata.

Signed-off-by: Willem de Bruijn <willemb@google.com>

----

Changes (rfc -> v1)
  - add documentation
  - remove unnecessary skb->len test (thanks to Richard Cochran)
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-02-02 18:46:51 -08:00
Joe Stringer 74ed7ab926 openvswitch: Add support for unique flow IDs.
Previously, flows were manipulated by userspace specifying a full,
unmasked flow key. This adds significant burden onto flow
serialization/deserialization, particularly when dumping flows.

This patch adds an alternative way to refer to flows using a
variable-length "unique flow identifier" (UFID). At flow setup time,
userspace may specify a UFID for a flow, which is stored with the flow
and inserted into a separate table for lookup, in addition to the
standard flow table. Flows created using a UFID must be fetched or
deleted using the UFID.

All flow dump operations may now be made more terse with OVS_UFID_F_*
flags. For example, the OVS_UFID_F_OMIT_KEY flag allows responses to
omit the flow key from a datapath operation if the flow has a
corresponding UFID. This significantly reduces the time spent assembling
and transacting netlink messages. With all OVS_UFID_F_OMIT_* flags
enabled, the datapath only returns the UFID and statistics for each flow
during flow dump, increasing ovs-vswitchd revalidator performance by 40%
or more.

Signed-off-by: Joe Stringer <joestringer@nicira.com>
Acked-by: Pravin B Shelar <pshelar@nicira.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-01-26 15:45:50 -08:00
Harout Hedeshian c2943f1453 net: ipv6: Add sysctl entry to disable MTU updates from RA
The kernel forcefully applies MTU values received in router
advertisements provided the new MTU is less than the current. This
behavior is undesirable when the user space is managing the MTU. Instead
a sysctl flag 'accept_ra_mtu' is introduced such that the user space
can control whether or not RA provided MTU updates should be applied. The
default behavior is unchanged; user space must explicitly set this flag
to 0 for RA MTUs to be ignored.

Signed-off-by: Harout Hedeshian <harouth@codeaurora.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-01-25 14:54:41 -08:00
David S. Miller 4e7a84b1a5 Merge git://git.kernel.org/pub/scm/linux/kernel/git/pablo/nf-next
Pablo Neira Ayuso says:

====================
netfilter updates for net-next

The following patchset contains netfilter updates for net-next, just a
bunch of cleanups and small enhancement to selectively flush conntracks
in ctnetlink, more specifically the patches are:

1) Rise default number of buckets in conntrack from 16384 to 65536 in
   systems with >= 4GBytes, patch from Marcelo Leitner.

2) Small refactor to save one level on indentation in xt_osf, from
   Joe Perches.

3) Remove unnecessary sizeof(char) in nf_log, from Fabian Frederick.

4) Another small cleanup to remove redundant variable in nfnetlink,
   from Duan Jiong.

5) Fix compilation warning in nfnetlink_cthelper on parisc, from
   Chen Gang.

6) Fix wrong format in debugging for ctseqadj, from Gao feng.

7) Selective conntrack flushing through the mark for ctnetlink, patch
   from Kristian Evensen.

8) Remove nf_ct_conntrack_flush_report() exported symbol now that is
   not required anymore after the selective flushing patch, again from
   Kristian.
====================

Signed-off-by: David S. Miller <davem@davemloft.net>
2015-01-15 01:50:25 -05:00
David S. Miller 3f3558bb51 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net
Conflicts:
	drivers/net/xen-netfront.c

Minor overlapping changes in xen-netfront.c, mostly to do
with some buffer management changes alongside the split
of stats into TX and RX.

Signed-off-by: David S. Miller <davem@davemloft.net>
2015-01-15 00:53:17 -05:00
Jiri Pirko df8a39defa net: rename vlan_tx_* helpers since "tx" is misleading there
The same macros are used for rx as well. So rename it.

Signed-off-by: Jiri Pirko <jiri@resnulli.us>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-01-13 17:51:08 -05:00
Ani Sinha 25050c63a5 update ip-sysctl.txt documentation (v2)
Update documentation to reflect the fact that
/proc/sys/net/ipv4/route/max_size is no longer used for ipv4.

Signed-off-by: Ani Sinha <ani@arista.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-01-12 15:38:43 -05:00
Willem de Bruijn d3b4b26173 doc: fix the compile fix of txtimestamp.c
A fix to ipv6 structure definitions removed the now superfluous
definition of in6_pktinfo in this file.

But, use of the glibc definition requires defining _GNU_SOURCE
(see also https://sourceware.org/bugzilla/show_bug.cgi?id=6775).

Before this change, the following would fail for me:

  make
  make headers_install
  make M=Documentation/networking/timestamping

with

  Documentation/networking/timestamping/txtimestamp.c: In function '__recv_errmsg_cmsg':
  Documentation/networking/timestamping/txtimestamp.c:205:33: error: dereferencing pointer to incomplete type
  Documentation/networking/timestamping/txtimestamp.c:206:23: error: dereferencing pointer to incomplete type

After this patch compilation succeeded.

Fixes: cd91cc5bdd ("doc: fix the compile error of txtimestamp.c")
Signed-off-by: Willem de Bruijn <willemb@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-01-11 21:56:00 -05:00
WANG Cong cd91cc5bdd doc: fix the compile error of txtimestamp.c
Vinson reported:

  HOSTCC  Documentation/networking/timestamping/txtimestamp
Documentation/networking/timestamping/txtimestamp.c:64:8: error:
redefinition of ‘struct in6_pktinfo’
 struct in6_pktinfo {
        ^
In file included from /usr/include/arpa/inet.h:23:0,
                 from Documentation/networking/timestamping/txtimestamp.c:33:
/usr/include/netinet/in.h:456:8: note: originally defined here
 struct in6_pktinfo
        ^

After we sync with libc header, we don't need this ugly hack any more.

Reported-by: Vinson Lee <vlee@twopensource.com>
Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2015-01-08 19:29:11 -08:00
Henrik Austad 9007fd3241 Update of Documentation/networking/00-INDEX
- altera_tse.txt was added by 04add4ab (Add Altera Ethernet (TSE)
  Documentation)
- cdc_mbim.txt was added by a563babe (cdc_mbim: add driver
  documentation)
- dctcp.txt was added by e3118e83 (tcp: add DCTCP congestion control
  algorithm)

CC: Jonathan Corbet <corbet@lwn.net>
CC: "David S. Miller" <davem@davemloft.net>
CC: linux-doc@vger.kernel.org
CC: linux-kernel@vger.kernel.org
Signed-off-by: Henrik Austad <henrik@austad.us>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
2014-12-29 15:28:11 -07:00
Marcelo Leitner 88eab472ec netfilter: conntrack: adjust nf_conntrack_buckets default value
Manually bumping either nf_conntrack_buckets or nf_conntrack_max has
become a common task as our Linux servers tend to serve more and more
clients/applications, so let's adjust nf_conntrack_buckets this to a
more updated value.

Now for systems with more than 4GB of memory, nf_conntrack_buckets
becomes 65536 instead of 16384, resulting in nf_conntrack_max=256k
entries.

Signed-off-by: Marcelo Ricardo Leitner <mleitner@redhat.com>
Acked-by: Jesper Dangaard Brouer <brouer@redhat.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
2014-12-23 14:20:10 +01:00
Duan Jiong fd223068fc fib_trie.txt: fix typo
Fix the typo, there should be "It".
On the other hand, fix whitespace errors detected by checkpatch.pl

Signed-off-by: Duan Jiong <duanj.fnst@cn.fujitsu.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-12-15 11:45:15 -05:00
Rami Rosen 6dc696401a Documentation (ixgbe.txt): use a decimal address.
This patch fixes the erronous usage of an hexadecimal address in the
example, by replacing it with a decimal address.

Signed-off-by: Rami Rosen <ramirose@gmail.com>
Acked-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-12-09 16:02:32 -05:00
Willem de Bruijn cbd3aad5ce net-timestamp: expand documentation and test
Documentation:
  expand explanation of timestamp counter

Test:
  new: flag -I requests and prints PKTINFO
  new: flag -x prints payload (possibly truncated)
  fix: remove pretty print that breaks common flag '-l 1'

Signed-off-by: Willem de Bruijn <willemb@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-12-08 20:20:48 -05:00
Willem de Bruijn 829ae9d611 net-timestamp: allow reading recv cmsg on errqueue with origin tstamp
Allow reading of timestamps and cmsg at the same time on all relevant
socket families. One use is to correlate timestamps with egress
device, by asking for cmsg IP_PKTINFO.

on AF_INET sockets, call the relevant function (ip_cmsg_recv). To
avoid changing legacy expectations, only do so if the caller sets a
new timestamping flag SOF_TIMESTAMPING_OPT_CMSG.

on AF_INET6 sockets, IPV6_PKTINFO and all other recv cmsg are already
returned for all origins. only change is to set ifindex, which is
not initialized for all error origins.

In both cases, only generate the pktinfo message if an ifindex is
known. This is not the case for ACK timestamps.

The difference between the protocol families is probably a historical
accident as a result of the different conditions for generating cmsg
in the relevant ip(v6)_recv_error function:

ipv4:        if (serr->ee.ee_origin == SO_EE_ORIGIN_ICMP) {
ipv6:        if (serr->ee.ee_origin != SO_EE_ORIGIN_LOCAL) {

At one time, this was the same test bar for the ICMP/ICMP6
distinction. This is no longer true.

Signed-off-by: Willem de Bruijn <willemb@google.com>

----

Changes
  v1 -> v2
    large rewrite
    - integrate with existing pktinfo cmsg generation code
    - on ipv4: only send with new flag, to maintain legacy behavior
    - on ipv6: send at most a single pktinfo cmsg
    - on ipv6: initialize fields if not yet initialized

The recv cmsg interfaces are also relevant to the discussion of
whether looping packet headers is problematic. For v6, cmsgs that
identify many headers are already returned. This patch expands
that to v4. If it sounds reasonable, I will follow with patches

1. request timestamps without payload with SOF_TIMESTAMPING_OPT_TSONLY
   (http://patchwork.ozlabs.org/patch/366967/)
2. sysctl to conditionally drop all timestamps that have payload or
   cmsg from users without CAP_NET_RAW.
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-12-08 20:20:48 -05:00
Jiri Pirko 007f790c82 net: introduce generic switch devices support
The goal of this is to provide a possibility to support various switch
chips. Drivers should implement relevant ndos to do so. Now there is
only one ndo defined:
- for getting physical switch id is in place.

Note that user can use random port netdevice to access the switch.

Signed-off-by: Jiri Pirko <jiri@resnulli.us>
Reviewed-by: Thomas Graf <tgraf@suug.ch>
Acked-by: Andy Gospodarek <gospo@cumulusnetworks.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-12-02 20:01:20 -08:00
David S. Miller 60b7379dc5 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2014-11-29 20:47:48 -08:00
Andrew Lutomirski 138a7f4927 net-timestamp: Fix a documentation typo
SOF_TIMESTAMPING_OPT_ID puts the id in ee_data, not ee_info.

Cc: Willem de Bruijn <willemb@google.com>
Signed-off-by: Andy Lutomirski <luto@amacapital.net>
Acked-by: Willem de Bruijn <willemb@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-11-25 13:35:26 -05:00
Mahesh Bandewar 2ad7bf3638 ipvlan: Initial check-in of the IPVLAN driver.
This driver is very similar to the macvlan driver except that it
uses L3 on the frame to determine the logical interface while
functioning as packet dispatcher. It inherits L2 of the master
device hence the packets on wire will have the same L2 for all
the packets originating from all virtual devices off of the same
master device.

This driver was developed keeping the namespace use-case in
mind. Hence most of the examples given here take that as the
base setup where main-device belongs to the default-ns and
virtual devices are assigned to the additional namespaces.

The device operates in two different modes and the difference
in these two modes in primarily in the TX side.

(a) L2 mode : In this mode, the device behaves as a L2 device.
TX processing upto L2 happens on the stack of the virtual device
associated with (namespace). Packets are switched after that
into the main device (default-ns) and queued for xmit.

RX processing is simple and all multicast, broadcast (if
applicable), and unicast belonging to the address(es) are
delivered to the virtual devices.

(b) L3 mode : In this mode, the device behaves like a L3 device.
TX processing upto L3 happens on the stack of the virtual device
associated with (namespace). Packets are switched to the
main-device (default-ns) for the L2 processing. Hence the routing
table of the default-ns will be used in this mode.

RX processins is somewhat similar to the L2 mode except that in
this mode only Unicast packets are delivered to the virtual device
while main-dev will handle all other packets.

The devices can be added using the "ip" command from the iproute2
package -

	ip link add link <master> <virtual> type ipvlan mode [ l2 | l3 ]

Signed-off-by: Mahesh Bandewar <maheshb@google.com>
Cc: Eric Dumazet <edumazet@google.com>
Cc: Maciej Żenczykowski <maze@google.com>
Cc: Laurent Chavey <chavey@google.com>
Cc: Tim Hockin <thockin@google.com>
Cc: Brandon Philips <brandon.philips@coreos.com>
Cc: Pavel Emelianov <xemul@parallels.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-11-24 15:29:18 -05:00
Giuseppe CAVALLARO 233b36cf1f stmmac: update driver documentation
Recently many changes have been done inside the driver
so this patch updates the driver's doc for example reviewing
information for the rx and tx processes that are managed
by napi method, adding new information for missing glue-logic files
etc.

Signed-off-by: Giuseppe Cavallaro <peppe.cavallaro@st.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-11-19 15:04:57 -05:00
David S. Miller 4e84b496fd Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2014-11-06 22:01:18 -05:00
Loganaden Velvindron 219b5f29a5 net: Add missing descriptions for fwmark_reflect for ipv4 and ipv6.
It was initially sent by Lorenzo Colitti, but was subsequently
lost in the final diff he submitted.

Signed-off-by: Loganaden Velvindron <logan@elandsys.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-11-05 15:43:57 -05:00
Erik Kline 7fd2561e4e net: ipv6: Add a sysctl to make optimistic addresses useful candidates
Add a sysctl that causes an interface's optimistic addresses
to be considered equivalent to other non-deprecated addresses
for source address selection purposes.  Preferred addresses
will still take precedence over optimistic addresses, subject
to other ranking in the source address selection algorithm.

This is useful where different interfaces are connected to
different networks from different ISPs (e.g., a cell network
and a home wifi network).

The current behaviour complies with RFC 3484/6724, and it
makes sense if the host has only one interface, or has
multiple interfaces on the same network (same or cooperating
administrative domain(s), but not in the multiple distinct
networks case.

For example, if a mobile device has an IPv6 address on an LTE
network and then connects to IPv6-enabled wifi, while the wifi
IPv6 address is undergoing DAD, IPv6 connections will try use
the wifi default route with the LTE IPv6 address, and will get
stuck until they time out.

Also, because optimistic nodes can receive frames, issue
an RTM_NEWADDR as soon as DAD starts (with the IFA_F_OPTIMSTIC
flag appropriately set).  A second RTM_NEWADDR is sent if DAD
completes (the address flags have changed), otherwise an
RTM_DELADDR is sent.

Also: add an entry in ip-sysctl.txt for optimistic_dad.

Signed-off-by: Erik Kline <ek@google.com>
Acked-by: Lorenzo Colitti <lorenzo@google.com>
Acked-by: Hannes Frederic Sowa <hannes@stressinduktion.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-10-29 15:11:36 -04:00
Eric Dumazet dca145ffaa tcp: allow for bigger reordering level
While testing upcoming Yaogong patch (converting out of order queue
into an RB tree), I hit the max reordering level of linux TCP stack.

Reordering level was limited to 127 for no good reason, and some
network setups [1] can easily reach this limit and get limited
throughput.

Allow a new max limit of 300, and add a sysctl to allow admins to even
allow bigger (or lower) values if needed.

[1] Aggregation of links, per packet load balancing, fabrics not doing
 deep packet inspections, alternative TCP congestion modules...

Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: Yaogong Wang <wygivan@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-10-29 15:05:15 -04:00
Li RongQing 1a9525f68e Documentation: replace __sk_run_filter with __bpf_prog_run
__sk_run_filter has been renamed as __bpf_prog_run, so replace them in comments

Signed-off-by: Li RongQing <roy.qing.li@gmail.com>
Acked-by: Alexei Starovoitov <ast@plumgrid.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-10-10 15:10:50 -04:00
Linus Torvalds 35a9ad8af0 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next
Pull networking updates from David Miller:
 "Most notable changes in here:

   1) By far the biggest accomplishment, thanks to a large range of
      contributors, is the addition of multi-send for transmit.  This is
      the result of discussions back in Chicago, and the hard work of
      several individuals.

      Now, when the ->ndo_start_xmit() method of a driver sees
      skb->xmit_more as true, it can choose to defer the doorbell
      telling the driver to start processing the new TX queue entires.

      skb->xmit_more means that the generic networking is guaranteed to
      call the driver immediately with another SKB to send.

      There is logic added to the qdisc layer to dequeue multiple
      packets at a time, and the handling mis-predicted offloads in
      software is now done with no locks held.

      Finally, pktgen is extended to have a "burst" parameter that can
      be used to test a multi-send implementation.

      Several drivers have xmit_more support: i40e, igb, ixgbe, mlx4,
      virtio_net

      Adding support is almost trivial, so export more drivers to
      support this optimization soon.

      I want to thank, in no particular or implied order, Jesper
      Dangaard Brouer, Eric Dumazet, Alexander Duyck, Tom Herbert, Jamal
      Hadi Salim, John Fastabend, Florian Westphal, Daniel Borkmann,
      David Tat, Hannes Frederic Sowa, and Rusty Russell.

   2) PTP and timestamping support in bnx2x, from Michal Kalderon.

   3) Allow adjusting the rx_copybreak threshold for a driver via
      ethtool, and add rx_copybreak support to enic driver.  From
      Govindarajulu Varadarajan.

   4) Significant enhancements to the generic PHY layer and the bcm7xxx
      driver in particular (EEE support, auto power down, etc.) from
      Florian Fainelli.

   5) Allow raw buffers to be used for flow dissection, allowing drivers
      to determine the optimal "linear pull" size for devices that DMA
      into pools of pages.  The objective is to get exactly the
      necessary amount of headers into the linear SKB area pre-pulled,
      but no more.  The new interface drivers use is eth_get_headlen().
      From WANG Cong, with driver conversions (several had their own
      by-hand duplicated implementations) by Alexander Duyck and Eric
      Dumazet.

   6) Support checksumming more smoothly and efficiently for
      encapsulations, and add "foo over UDP" facility.  From Tom
      Herbert.

   7) Add Broadcom SF2 switch driver to DSA layer, from Florian
      Fainelli.

   8) eBPF now can load programs via a system call and has an extensive
      testsuite.  Alexei Starovoitov and Daniel Borkmann.

   9) Major overhaul of the packet scheduler to use RCU in several major
      areas such as the classifiers and rate estimators.  From John
      Fastabend.

  10) Add driver for Intel FM10000 Ethernet Switch, from Alexander
      Duyck.

  11) Rearrange TCP_SKB_CB() to reduce cache line misses, from Eric
      Dumazet.

  12) Add Datacenter TCP congestion control algorithm support, From
      Florian Westphal.

  13) Reorganize sk_buff so that __copy_skb_header() is significantly
      faster.  From Eric Dumazet"

* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next: (1558 commits)
  netlabel: directly return netlbl_unlabel_genl_init()
  net: add netdev_txq_bql_{enqueue, complete}_prefetchw() helpers
  net: description of dma_cookie cause make xmldocs warning
  cxgb4: clean up a type issue
  cxgb4: potential shift wrapping bug
  i40e: skb->xmit_more support
  net: fs_enet: Add NAPI TX
  net: fs_enet: Remove non NAPI RX
  r8169:add support for RTL8168EP
  net_sched: copy exts->type in tcf_exts_change()
  wimax: convert printk to pr_foo()
  af_unix: remove 0 assignment on static
  ipv6: Do not warn for informational ICMP messages, regardless of type.
  Update Intel Ethernet Driver maintainers list
  bridge: Save frag_max_size between PRE_ROUTING and POST_ROUTING
  tipc: fix bug in multicast congestion handling
  net: better IFF_XMIT_DST_RELEASE support
  net/mlx4_en: remove NETDEV_TX_BUSY
  3c59x: fix bad split of cpu_to_le32(pci_map_single())
  net: bcmgenet: fix Tx ring priority programming
  ...
2014-10-08 21:40:54 -04:00
Linus Torvalds 6325e940e7 arm64 updates for 3.18:
- eBPF JIT compiler for arm64
 - CPU suspend backend for PSCI (firmware interface) with standard idle
   states defined in DT (generic idle driver to be merged via a different
   tree)
 - Support for CONFIG_DEBUG_SET_MODULE_RONX
 - Support for unmapped cpu-release-addr (outside kernel linear mapping)
 - set_arch_dma_coherent_ops() implemented and bus notifiers removed
 - EFI_STUB improvements when base of DRAM is occupied
 - Typos in KGDB macros
 - Clean-up to (partially) allow kernel building with LLVM
 - Other clean-ups (extern keyword, phys_addr_t usage)
 -----BEGIN PGP SIGNATURE-----
 Version: GnuPG v1
 
 iQIcBAABAgAGBQJUNB6NAAoJEGvWsS0AyF7x22sP/1qPQvFoY71fSqTZmSY+kfgW
 UMXhDFZOd+khD2TPHWptbgBRDElTQjRPHyISv/8ILKwDNoMlUDLlYkp1XPLM/nlB
 ea9ou2GX8iktqgM2JF5r4vk1hjH6JqEGOUHyWKZc7ibphTVm3dhg3nWL1A4peOUG
 0UyX79kl8BLAaggLSUhjtUz1GMpSNlb6Pc1ForUXaPMayBlOcVoOzh1ir7b5wb3e
 IvotUY1gv+opE9uK0QPr1AJSfpCogPEfQ2TSCP8MQZjxkrEz69n0HaFvdy60rwf4
 DaJiqBoQ5MSP3Bw+qvoYgyz+tfiPFAvEF+O3YQ5x3LBTteoooriFYH4mL7DsicAs
 2WLor/342mHykE0bOc44/gNl8B/xaZNzvO2ezLYrjVGsiY2QHTZ7fXB8arPUvQSS
 RUXVfHmcv4qthZjI17rgreBKvsfeFIMighSfvMJnVhGqDSvB8abjiPwZjzqB91Bq
 pu5MDitNgR3k3ctwzRaS6JtH2CluVFv97xIS4VaD/hm3JnS5NPeTXFou3Gb3lvon
 d/wXOIB3vY8FDMIt+BMCQPzWiU0liZ/sN7p1bsOmkgZ1wLOZ0nmsaHF09PDRGbtA
 vifopwaw9qtNlcVrTB/rDBCDaT0Ds/mTYD/a3+ch5CYUeLmQmfW/vBMfq/3gUt65
 JdI/nTVXawbl2CpBWw36
 =SAfQ
 -----END PGP SIGNATURE-----

Merge tag 'arm64-upstream' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux

Pull arm64 updates from Catalin Marinas:
 - eBPF JIT compiler for arm64
 - CPU suspend backend for PSCI (firmware interface) with standard idle
   states defined in DT (generic idle driver to be merged via a
   different tree)
 - Support for CONFIG_DEBUG_SET_MODULE_RONX
 - Support for unmapped cpu-release-addr (outside kernel linear mapping)
 - set_arch_dma_coherent_ops() implemented and bus notifiers removed
 - EFI_STUB improvements when base of DRAM is occupied
 - Typos in KGDB macros
 - Clean-up to (partially) allow kernel building with LLVM
 - Other clean-ups (extern keyword, phys_addr_t usage)

* tag 'arm64-upstream' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux: (51 commits)
  arm64: Remove unneeded extern keyword
  ARM64: make of_device_ids const
  arm64: Use phys_addr_t type for physical address
  aarch64: filter $x from kallsyms
  arm64: Use DMA_ERROR_CODE to denote failed allocation
  arm64: Fix typos in KGDB macros
  arm64: insn: Add return statements after BUG_ON()
  arm64: debug: don't re-enable debug exceptions on return from el1_dbg
  Revert "arm64: dmi: Add SMBIOS/DMI support"
  arm64: Implement set_arch_dma_coherent_ops() to replace bus notifiers
  of: amba: use of_dma_configure for AMBA devices
  arm64: dmi: Add SMBIOS/DMI support
  arm64: Correct ftrace calls to aarch64_insn_gen_branch_imm()
  arm64:mm: initialize max_mapnr using function set_max_mapnr
  setup: Move unmask of async interrupts after possible earlycon setup
  arm64: LLVMLinux: Fix inline arm64 assembly for use with clang
  arm64: pageattr: Correctly adjust unaligned start addresses
  net: bpf: arm64: fix module memory leak when JIT image build fails
  arm64: add PSCI CPU_SUSPEND based cpu_suspend support
  arm64: kernel: introduce cpu_init_idle CPU operation
  ...
2014-10-08 05:34:24 -04:00
Linus Torvalds b6420ebd4a Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/doc
Pull documentation updates from Jiri Kosina:
 "Updates to kernel documentation.

  I took this over (hopefully temporarily) from Randy who was not
  willing to maintain it any longer.  This pile mostly is a relay of
  queue that Randy already had in his tree"

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/doc:
  Documentation: fix broken v4l-utils URL
  Documentation: update include path for mpssd
  Documentation: correct parameter error for dma_mapping_error
  MAINTAINERS: update location of linux-doc tree
  Documentation: remove networking/.gitignore
  tools: add more endian.h macros
  Make Documenation depend on headers_install
  Docs: this_cpu_ops: remove redundant add forms
  Documentation: disable vdso_test to avoid breakage with old glibc
  Documentation: update vDSO makefile to build portable examples
  Documentation: update .gitignore files
  Documentation: support glibc versions without htole macros
  v4l2-pci-skeleton: Only build if PCI is available
  Documentation: fix misc. warnings
  Documentation: make functions static to avoid prototype warnings
  Documentation: add makefiles for more targets
  Documentation: use subdir-y to avoid unnecessary built-in.o files
2014-10-07 21:14:57 -04:00
Linus Torvalds d0cd84817c dmaengine-3.17
1/ Step down as dmaengine maintainer see commit 08223d80df "dmaengine
    maintainer update"
 
 2/ Removal of net_dma, as it has been marked 'broken' since 3.13 (commit
    7787380336 "net_dma: mark broken"), without reports of performance
    regression.
 
 3/ Miscellaneous fixes
 -----BEGIN PGP SIGNATURE-----
 Version: GnuPG v1
 
 iQIcBAABAgAGBQJUKDLKAAoJEB7SkWpmfYgC7wwP/iNHqRjf1suMUTBIF3P6Hgbe
 VCUwh0IkuujMPDG46WRn6cYzarRxVPLoGaLHLPszgjI6pmGPVv19wqeDOlUxtcmr
 0iQWEWv/zqseaAIW+4gj/WYCyMgKil49EUBJKCZCfNmIaad+e0pr8f0uE5yOkHPM
 tqWoZERu9A4dlXGr1TjeOZVzdnPrCt92MrLDN6ZZ6tMuJaEc5PauaLxKTeGy5fYj
 UB+k1xJQzECbsYfpB+uCVYl5/qPO1rNyuBYS8THCsW+JYmrbbfH2kkF2lo2FaUpO
 8Yd50FtzXHKWwAt7BzfIwU2M7x0wRmryrC/xsQi6M+WmVeHYvvHUIpzaA66xRZ5x
 fCy3Fu8sEnmnmboAbh2v2c5uTycqRl2xPzbpLAuxglloXIxzi3ckp6ESF/Z4SldH
 oxIoEievN7lah3vKgvlHZYcWDzrYr8EKf/EzFe9RqDBQDKtzDzre1H9Uivr387Vm
 uFUcGHYG/GXuX47C7EUsMtaSW2UEoR2ytw/HR6CKFPTVXwAzEO6kA9vg0EqL0iIq
 2wVLgavlZuwegmaUBgnr+bgVZMvVN7OU7fAIRVe5xNO6itrPKvheSlQthmRiiq9C
 uzOu4PS6PexqzHUNPCcJpCsj+lawmCSrE0bxtPzTA/CQInVgWs219V9+W5Gn/0YA
 EARN9k6ueX9PZPQrPQLm
 =BBBv
 -----END PGP SIGNATURE-----

Merge tag 'dmaengine-3.17' of git://git.kernel.org/pub/scm/linux/kernel/git/djbw/dmaengine

Pull dmaengine updates from Dan Williams:
 "Even though this has fixes marked for -stable, given the size and the
  needed conflict resolutions this is 3.18-rc1/merge-window material.

  These patches have been languishing in my tree for a long while.  The
  fact that I do not have the time to do proper/prompt maintenance of
  this tree is a primary factor in the decision to step down as
  dmaengine maintainer.  That and the fact that the bulk of drivers/dma/
  activity is going through Vinod these days.

  The net_dma removal has not been in -next.  It has developed simple
  conflicts against mainline and net-next (for-3.18).

  Continuing thanks to Vinod for staying on top of drivers/dma/.

  Summary:

   1/ Step down as dmaengine maintainer see commit 08223d80df
      "dmaengine maintainer update"

   2/ Removal of net_dma, as it has been marked 'broken' since 3.13
      (commit 7787380336 "net_dma: mark broken"), without reports of
      performance regression.

   3/ Miscellaneous fixes"

* tag 'dmaengine-3.17' of git://git.kernel.org/pub/scm/linux/kernel/git/djbw/dmaengine:
  net: make tcp_cleanup_rbuf private
  net_dma: revert 'copied_early'
  net_dma: simple removal
  dmaengine maintainer update
  dmatest: prevent memory leakage on error path in thread
  ioat: Use time_before_jiffies()
  dmaengine: fix xor sources continuation
  dma: mv_xor: Rename __mv_xor_slot_cleanup() to mv_xor_slot_cleanup()
  dma: mv_xor: Remove all callers of mv_xor_slot_cleanup()
  dma: mv_xor: Remove unneeded mv_xor_clean_completed_slots() call
  ioat: Use pci_enable_msix_exact() instead of pci_enable_msix()
  drivers: dma: Include appropriate header file in dca.c
  drivers: dma: Mark functions as static in dma_v3.c
  dma: mv_xor: Add DMA API error checks
  ioat/dca: Use dev_is_pci() to check whether it is pci device
2014-10-07 20:39:25 -04:00
Alexei Starovoitov 38b2cf2982 net: pktgen: packet bursting via skb->xmit_more
This patch demonstrates the effect of delaying update of HW tailptr.
(based on earlier patch by Jesper)

burst=1 is the default. It sends one packet with xmit_more=false
burst=2 sends one packet with xmit_more=true and
        2nd copy of the same packet with xmit_more=false
burst=3 sends two copies of the same packet with xmit_more=true and
        3rd copy with xmit_more=false

Performance with ixgbe (usec 30):
burst=1  tx:9.2 Mpps
burst=2  tx:13.5 Mpps
burst=3  tx:14.5 Mpps full 10G line rate

Signed-off-by: Alexei Starovoitov <ast@plumgrid.com>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Acked-by: Jesper Dangaard Brouer <brouer@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-10-01 22:08:12 -04:00
Daniel Borkmann e3118e8359 net: tcp: add DCTCP congestion control algorithm
This work adds the DataCenter TCP (DCTCP) congestion control
algorithm [1], which has been first published at SIGCOMM 2010 [2],
resp. follow-up analysis at SIGMETRICS 2011 [3] (and also, more
recently as an informational IETF draft available at [4]).

DCTCP is an enhancement to the TCP congestion control algorithm for
data center networks. Typical data center workloads are i.e.
i) partition/aggregate (queries; bursty, delay sensitive), ii) short
messages e.g. 50KB-1MB (for coordination and control state; delay
sensitive), and iii) large flows e.g. 1MB-100MB (data update;
throughput sensitive). DCTCP has therefore been designed for such
environments to provide/achieve the following three requirements:

  * High burst tolerance (incast due to partition/aggregate)
  * Low latency (short flows, queries)
  * High throughput (continuous data updates, large file
    transfers) with commodity, shallow buffered switches

The basic idea of its design consists of two fundamentals: i) on the
switch side, packets are being marked when its internal queue
length > threshold K (K is chosen so that a large enough headroom
for marked traffic is still available in the switch queue); ii) the
sender/host side maintains a moving average of the fraction of marked
packets, so each RTT, F is being updated as follows:

 F := X / Y, where X is # of marked ACKs, Y is total # of ACKs
 alpha := (1 - g) * alpha + g * F, where g is a smoothing constant

The resulting alpha (iow: probability that switch queue is congested)
is then being used in order to adaptively decrease the congestion
window W:

 W := (1 - (alpha / 2)) * W

The means for receiving marked packets resp. marking them on switch
side in DCTCP is the use of ECN.

RFC3168 describes a mechanism for using Explicit Congestion Notification
from the switch for early detection of congestion, rather than waiting
for segment loss to occur.

However, this method only detects the presence of congestion, not
the *extent*. In the presence of mild congestion, it reduces the TCP
congestion window too aggressively and unnecessarily affects the
throughput of long flows [4].

DCTCP, as mentioned, enhances Explicit Congestion Notification (ECN)
processing to estimate the fraction of bytes that encounter congestion,
rather than simply detecting that some congestion has occurred. DCTCP
then scales the TCP congestion window based on this estimate [4],
thus it can derive multibit feedback from the information present in
the single-bit sequence of marks in its control law. And thus act in
*proportion* to the extent of congestion, not its *presence*.

Switches therefore set the Congestion Experienced (CE) codepoint in
packets when internal queue lengths exceed threshold K. Resulting,
DCTCP delivers the same or better throughput than normal TCP, while
using 90% less buffer space.

It was found in [2] that DCTCP enables the applications to handle 10x
the current background traffic, without impacting foreground traffic.
Moreover, a 10x increase in foreground traffic did not cause any
timeouts, and thus largely eliminates TCP incast collapse problems.

The algorithm itself has already seen deployments in large production
data centers since then.

We did a long-term stress-test and analysis in a data center, short
summary of our TCP incast tests with iperf compared to cubic:

This test measured DCTCP throughput and latency and compared it with
CUBIC throughput and latency for an incast scenario. In this test, 19
senders sent at maximum rate to a single receiver. The receiver simply
ran iperf -s.

The senders ran iperf -c <receiver> -t 30. All senders started
simultaneously (using local clocks synchronized by ntp).

This test was repeated multiple times. Below shows the results from a
single test. Other tests are similar. (DCTCP results were extremely
consistent, CUBIC results show some variance induced by the TCP timeouts
that CUBIC encountered.)

For this test, we report statistics on the number of TCP timeouts,
flow throughput, and traffic latency.

1) Timeouts (total over all flows, and per flow summaries):

            CUBIC            DCTCP
  Total     3227             25
  Mean       169.842          1.316
  Median     183              1
  Max        207              5
  Min        123              0
  Stddev      28.991          1.600

Timeout data is taken by measuring the net change in netstat -s
"other TCP timeouts" reported. As a result, the timeout measurements
above are not restricted to the test traffic, and we believe that it
is likely that all of the "DCTCP timeouts" are actually timeouts for
non-test traffic. We report them nevertheless. CUBIC will also include
some non-test timeouts, but they are drawfed by bona fide test traffic
timeouts for CUBIC. Clearly DCTCP does an excellent job of preventing
TCP timeouts. DCTCP reduces timeouts by at least two orders of
magnitude and may well have eliminated them in this scenario.

2) Throughput (per flow in Mbps):

            CUBIC            DCTCP
  Mean      521.684          521.895
  Median    464              523
  Max       776              527
  Min       403              519
  Stddev    105.891            2.601
  Fairness    0.962            0.999

Throughput data was simply the average throughput for each flow
reported by iperf. By avoiding TCP timeouts, DCTCP is able to
achieve much better per-flow results. In CUBIC, many flows
experience TCP timeouts which makes flow throughput unpredictable and
unfair. DCTCP, on the other hand, provides very clean predictable
throughput without incurring TCP timeouts. Thus, the standard deviation
of CUBIC throughput is dramatically higher than the standard deviation
of DCTCP throughput.

Mean throughput is nearly identical because even though cubic flows
suffer TCP timeouts, other flows will step in and fill the unused
bandwidth. Note that this test is something of a best case scenario
for incast under CUBIC: it allows other flows to fill in for flows
experiencing a timeout. Under situations where the receiver is issuing
requests and then waiting for all flows to complete, flows cannot fill
in for timed out flows and throughput will drop dramatically.

3) Latency (in ms):

            CUBIC            DCTCP
  Mean      4.0088           0.04219
  Median    4.055            0.0395
  Max       4.2              0.085
  Min       3.32             0.028
  Stddev    0.1666           0.01064

Latency for each protocol was computed by running "ping -i 0.2
<receiver>" from a single sender to the receiver during the incast
test. For DCTCP, "ping -Q 0x6 -i 0.2 <receiver>" was used to ensure
that traffic traversed the DCTCP queue and was not dropped when the
queue size was greater than the marking threshold. The summary
statistics above are over all ping metrics measured between the single
sender, receiver pair.

The latency results for this test show a dramatic difference between
CUBIC and DCTCP. CUBIC intentionally overflows the switch buffer
which incurs the maximum queue latency (more buffer memory will lead
to high latency.) DCTCP, on the other hand, deliberately attempts to
keep queue occupancy low. The result is a two orders of magnitude
reduction of latency with DCTCP - even with a switch with relatively
little RAM. Switches with larger amounts of RAM will incur increasing
amounts of latency for CUBIC, but not for DCTCP.

4) Convergence and stability test:

This test measured the time that DCTCP took to fairly redistribute
bandwidth when a new flow commences. It also measured DCTCP's ability
to remain stable at a fair bandwidth distribution. DCTCP is compared
with CUBIC for this test.

At the commencement of this test, a single flow is sending at maximum
rate (near 10 Gbps) to a single receiver. One second after that first
flow commences, a new flow from a distinct server begins sending to
the same receiver as the first flow. After the second flow has sent
data for 10 seconds, the second flow is terminated. The first flow
sends for an additional second. Ideally, the bandwidth would be evenly
shared as soon as the second flow starts, and recover as soon as it
stops.

The results of this test are shown below. Note that the flow bandwidth
for the two flows was measured near the same time, but not
simultaneously.

DCTCP performs nearly perfectly within the measurement limitations
of this test: bandwidth is quickly distributed fairly between the two
flows, remains stable throughout the duration of the test, and
recovers quickly. CUBIC, in contrast, is slow to divide the bandwidth
fairly, and has trouble remaining stable.

  CUBIC                      DCTCP

  Seconds  Flow 1  Flow 2    Seconds  Flow 1  Flow 2
   0       9.93    0          0       9.92    0
   0.5     9.87    0          0.5     9.86    0
   1       8.73    2.25       1       6.46    4.88
   1.5     7.29    2.8        1.5     4.9     4.99
   2       6.96    3.1        2       4.92    4.94
   2.5     6.67    3.34       2.5     4.93    5
   3       6.39    3.57       3       4.92    4.99
   3.5     6.24    3.75       3.5     4.94    4.74
   4       6       3.94       4       5.34    4.71
   4.5     5.88    4.09       4.5     4.99    4.97
   5       5.27    4.98       5       4.83    5.01
   5.5     4.93    5.04       5.5     4.89    4.99
   6       4.9     4.99       6       4.92    5.04
   6.5     4.93    5.1        6.5     4.91    4.97
   7       4.28    5.8        7       4.97    4.97
   7.5     4.62    4.91       7.5     4.99    4.82
   8       5.05    4.45       8       5.16    4.76
   8.5     5.93    4.09       8.5     4.94    4.98
   9       5.73    4.2        9       4.92    5.02
   9.5     5.62    4.32       9.5     4.87    5.03
  10       6.12    3.2       10       4.91    5.01
  10.5     6.91    3.11      10.5     4.87    5.04
  11       8.48    0         11       8.49    4.94
  11.5     9.87    0         11.5     9.9     0

SYN/ACK ECT test:

This test demonstrates the importance of ECT on SYN and SYN-ACK packets
by measuring the connection probability in the presence of competing
flows for a DCTCP connection attempt *without* ECT in the SYN packet.
The test was repeated five times for each number of competing flows.

              Competing Flows  1 |    2 |    4 |    8 |   16
                               ------------------------------
Mean Connection Probability    1 | 0.67 | 0.45 | 0.28 |    0
Median Connection Probability  1 | 0.65 | 0.45 | 0.25 |    0

As the number of competing flows moves beyond 1, the connection
probability drops rapidly.

Enabling DCTCP with this patch requires the following steps:

DCTCP must be running both on the sender and receiver side in your
data center, i.e.:

  sysctl -w net.ipv4.tcp_congestion_control=dctcp

Also, ECN functionality must be enabled on all switches in your
data center for DCTCP to work. The default ECN marking threshold (K)
heuristic on the switch for DCTCP is e.g., 20 packets (30KB) at
1Gbps, and 65 packets (~100KB) at 10Gbps (K > 1/7 * C * RTT, [4]).

In above tests, for each switch port, traffic was segregated into two
queues. For any packet with a DSCP of 0x01 - or equivalently a TOS of
0x04 - the packet was placed into the DCTCP queue. All other packets
were placed into the default drop-tail queue. For the DCTCP queue,
RED/ECN marking was enabled, here, with a marking threshold of 75 KB.
More details however, we refer you to the paper [2] under section 3).

There are no code changes required to applications running in user
space. DCTCP has been implemented in full *isolation* of the rest of
the TCP code as its own congestion control module, so that it can run
without a need to expose code to the core of the TCP stack, and thus
nothing changes for non-DCTCP users.

Changes in the CA framework code are minimal, and DCTCP algorithm
operates on mechanisms that are already available in most Silicon.
The gain (dctcp_shift_g) is currently a fixed constant (1/16) from
the paper, but we leave the option that it can be chosen carefully
to a different value by the user.

In case DCTCP is being used and ECN support on peer site is off,
DCTCP falls back after 3WHS to operate in normal TCP Reno mode.

ss {-4,-6} -t -i diag interface:

  ... dctcp wscale:7,7 rto:203 rtt:2.349/0.026 mss:1448 cwnd:2054
  ssthresh:1102 ce_state 0 alpha 15 ab_ecn 0 ab_tot 735584
  send 10129.2Mbps pacing_rate 20254.1Mbps unacked:1822 retrans:0/15
  reordering:101 rcv_space:29200

  ... dctcp-reno wscale:7,7 rto:201 rtt:0.711/1.327 ato:40 mss:1448
  cwnd:10 ssthresh:1102 fallback_mode send 162.9Mbps pacing_rate
  325.5Mbps rcv_rtt:1.5 rcv_space:29200

More information about DCTCP can be found in [1-4].

  [1] http://simula.stanford.edu/~alizade/Site/DCTCP.html
  [2] http://simula.stanford.edu/~alizade/Site/DCTCP_files/dctcp-final.pdf
  [3] http://simula.stanford.edu/~alizade/Site/DCTCP_files/dctcp_analysis-full.pdf
  [4] http://tools.ietf.org/html/draft-bensley-tcpm-dctcp-00

Joint work with Florian Westphal and Glenn Judd.

Signed-off-by: Daniel Borkmann <dborkman@redhat.com>
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Glenn Judd <glenn.judd@morganstanley.com>
Acked-by: Stephen Hemminger <stephen@networkplumber.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2014-09-29 00:13:10 -04:00
Dan Williams 7bced39751 net_dma: simple removal
Per commit "77873803363c net_dma: mark broken" net_dma is no longer used
and there is no plan to fix it.

This is the mechanical removal of bits in CONFIG_NET_DMA ifdef guards.
Reverting the remainder of the net_dma induced changes is deferred to
subsequent patches.

Marked for stable due to Roman's report of a memory leak in
dma_pin_iovec_pages():

    https://lkml.org/lkml/2014/9/3/177

Cc: Dave Jiang <dave.jiang@intel.com>
Cc: Vinod Koul <vinod.koul@intel.com>
Cc: David Whipple <whipple@securedatainnovations.ch>
Cc: Alexander Duyck <alexander.h.duyck@intel.com>
Cc: <stable@vger.kernel.org>
Reported-by: Roman Gushchin <klamm@yandex-team.ru>
Acked-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2014-09-28 07:05:16 -07:00