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* can: introduce new raw socket option to join the given CAN filtersOliver Hartkopp2015-04-011-2/+18
| | | | | | | | | | | | | | | | | | | | | 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>
* filter: introduce SKF_AD_VLAN_TPID BPF extensionMichal Sekletar2015-03-241-1/+2
| | | | | | | | | | | | | | | | | | | | | 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>
* ipv6: add documentation for stable_secret, idgen_delay and idgen_retries knobsHannes Frederic Sowa2015-03-231-0/+25
| | | | | | | | | 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>
* af_packet: pass checksum validation status to the userAlexander Drozdov2015-03-231-3/+10
| | | | | | | | | | | | 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>
* net: neighbour: Document {mcast, ucast}_solicit, mcast_resolicit.YOSHIFUJI Hideaki/吉藤英明2015-03-201-1/+13
| | | | | Signed-off-by: YOSHIFUJI Hideaki <hideaki.yoshifuji@miraclelinux.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* net: Add max rate tx queue attributeJohn Fastabend2015-03-181-0/+9
| | | | | | | | | | | | | 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>
* neterion: remove reference to ifconfigstephen hemminger2015-03-082-2/+2
| | | | | | | | 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>
* ipv4: Documenting two sysctls for tcp PMTU probeFan Du2015-03-061-0/+10
| | | | | | | | | 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>
* mpls: Add a sysctl to control the size of the mpls label tableEric W. Biederman2015-03-041-0/+20
| | | | | | | | | | | | | | | | 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>
* Merge git://git.kernel.org/pub/scm/linux/kernel/git/pablo/nf-nextDavid S. Miller2015-03-021-0/+21
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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>
| * ipvs: allow rescheduling of new connections when port reuse is detectedMarcelo Ricardo Leitner2015-02-251-0/+21
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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>
* | pktgen: Correct documentation of module name and commandBen Hutchings2015-02-231-2/+2
| | | | | | | | | | | | | | | | | | | | 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>
* | samples/pktgen: Add sample scripts for pktgen facilityBen Hutchings2015-02-231-6/+6
| | | | | | | | | | | | | | | | | | | | | | | | | | 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>
* | pktgen: Fix grammar errors and some poor wording in documentationBen Hutchings2015-02-231-26/+30
| | | | | | | | | | | | | | | | 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>
* | pktgen: Delete the original date from documentationBen Hutchings2015-02-231-2/+0
| | | | | | | | | | | | | | | | 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>
* | Merge tag 'docs-for-linus' of git://git.lwn.net/linux-2.6Linus Torvalds2015-02-112-3/+7
|\ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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 ...
| * | can-doc: Fixed a wrong filepath in can.txtStefan Tatschner2015-02-051-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | <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>
| * | Update of Documentation/networking/00-INDEXHenrik Austad2014-12-291-2/+6
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | - 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>
* | | tcp: helpers to mitigate ACK loops by rate-limiting out-of-window dupacksNeal Cardwell2015-02-081-0/+22
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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>
* | | Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/netDavid S. Miller2015-02-051-10/+3
|\ \ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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>
| * | | Documentation: Update netlink_mmap.txtRichard Weinberger2015-02-021-10/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Update netlink_mmap.txt wrt. commit 4682a0358639b29cf ("netlink: Always copy on mmap TX."). Signed-off-by: Richard Weinberger <richard@nod.at> Signed-off-by: David S. Miller <davem@davemloft.net>
* | | | net-timestamp: no-payload option in txtimestamp testWillem de Bruijn2015-02-021-4/+24
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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>
* | | | net-timestamp: no-payload optionWillem de Bruijn2015-02-021-0/+21
| |_|/ |/| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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>
* | | openvswitch: Add support for unique flow IDs.Joe Stringer2015-01-261-0/+13
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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>
* | | net: ipv6: Add sysctl entry to disable MTU updates from RAHarout Hedeshian2015-01-251-0/+7
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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>
* | | Merge git://git.kernel.org/pub/scm/linux/kernel/git/pablo/nf-nextDavid S. Miller2015-01-151-1/+2
|\ \ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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>
| * | | netfilter: conntrack: adjust nf_conntrack_buckets default valueMarcelo Leitner2014-12-231-1/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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>
* | | | Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/netDavid S. Miller2015-01-151-0/+2
|\ \ \ \ | | |/ / | |/| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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>
| * | | update ip-sysctl.txt documentation (v2)Ani Sinha2015-01-121-0/+2
| | |/ | |/| | | | | | | | | | | | | | | | | | | 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>
* | | net: rename vlan_tx_* helpers since "tx" is misleading thereJiri Pirko2015-01-131-2/+2
| | | | | | | | | | | | | | | | | | | | | 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>
* | | doc: fix the compile fix of txtimestamp.cWillem de Bruijn2015-01-111-0/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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: cd91cc5bdddf ("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>
* | | doc: fix the compile error of txtimestamp.cWANG Cong2015-01-081-8/+0
|/ / | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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>
* | fib_trie.txt: fix typoDuan Jiong2014-12-151-2/+2
|/ | | | | | | | 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>
* Documentation (ixgbe.txt): use a decimal address.Rami Rosen2014-12-091-1/+1
| | | | | | | | | 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>
* net-timestamp: expand documentation and testWillem de Bruijn2014-12-082-20/+93
| | | | | | | | | | | | | 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>
* net-timestamp: allow reading recv cmsg on errqueue with origin tstampWillem de Bruijn2014-12-081-1/+11
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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>
* net: introduce generic switch devices supportJiri Pirko2014-12-021-0/+59
| | | | | | | | | | | | | | 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>
* Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/netDavid S. Miller2014-11-291-1/+1
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| * net-timestamp: Fix a documentation typoAndrew Lutomirski2014-11-251-1/+1
| | | | | | | | | | | | | | | | | | 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>
* | ipvlan: Initial check-in of the IPVLAN driver.Mahesh Bandewar2014-11-241-0/+107
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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>
* | stmmac: update driver documentationGiuseppe CAVALLARO2014-11-191-67/+65
| | | | | | | | | | | | | | | | | | | | | | 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>
* | Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/netDavid S. Miller2014-11-061-0/+14
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| * net: Add missing descriptions for fwmark_reflect for ipv4 and ipv6.Loganaden Velvindron2014-11-051-0/+14
| | | | | | | | | | | | | | | | 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>
* | net: ipv6: Add a sysctl to make optimistic addresses useful candidatesErik Kline2014-10-291-0/+13
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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>
* | tcp: allow for bigger reordering levelEric Dumazet2014-10-292-6/+11
|/ | | | | | | | | | | | | | | | | | | 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>
* Documentation: replace __sk_run_filter with __bpf_prog_runLi RongQing2014-10-101-2/+2
| | | | | | | | __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>
* Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-nextLinus Torvalds2014-10-087-92/+1110
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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 ...
| * net: pktgen: packet bursting via skb->xmit_moreAlexei Starovoitov2014-10-011-0/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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>
| * net: tcp: add DCTCP congestion control algorithmDaniel Borkmann2014-09-291-0/+43
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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>
| * bpf: verifier (add docs)Alexei Starovoitov2014-09-261-0/+224
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | this patch adds all of eBPF verfier documentation and empty bpf_check() The end goal for the verifier is to statically check safety of the program. Verifier will catch: - loops - out of range jumps - unreachable instructions - invalid instructions - uninitialized register access - uninitialized stack access - misaligned stack access - out of range stack access - invalid calling convention More details in Documentation/networking/filter.txt Signed-off-by: Alexei Starovoitov <ast@plumgrid.com> Signed-off-by: David S. Miller <davem@davemloft.net>
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