- 02 10月, 2014 12 次提交
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由 Tom Herbert 提交于
Call skb_set_inner_ipproto to set inner IP protocol to IPPROTO_IPV6 before tunnel_xmit. This is needed if UDP encapsulation (fou) is being done. Signed-off-by: NTom Herbert <therbert@google.com> Signed-off-by: NDavid S. Miller <davem@davemloft.net>
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由 Tom Herbert 提交于
skb_udp_segment is the function called from udp4_ufo_fragment to segment a UDP tunnel packet. This function currently assumes segmentation is transparent Ethernet bridging (i.e. VXLAN encapsulation). This patch generalizes the function to operate on either Ethertype or IP protocol. The inner_protocol field must be set to the protocol of the inner header. This can now be either an Ethertype or an IP protocol (in a union). A new flag in the skbuff indicates which type is effective. skb_set_inner_protocol and skb_set_inner_ipproto helper functions were added to set the inner_protocol. These functions are called from the point where the tunnel encapsulation is occuring. When skb_udp_tunnel_segment is called, the function to segment the inner packet is selected based on the inner IP or Ethertype. In the case of an IP protocol encapsulation, the function is derived from inet[6]_offloads. In the case of Ethertype, skb->protocol is set to the inner_protocol and skb_mac_gso_segment is called. (GRE currently does this, but it might be possible to lookup the protocol in offload_base and call the appropriate segmenation function directly). Signed-off-by: NTom Herbert <therbert@google.com> Signed-off-by: NDavid S. Miller <davem@davemloft.net>
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由 Eric Dumazet 提交于
Fast clone cloning can actually avoid an atomic_inc(), if we guarantee prior clone_ref value is 1. This requires a change kfree_skbmem(), to perform the atomic_dec_and_test() on clone_ref before setting fclone to SKB_FCLONE_UNAVAILABLE. Signed-off-by: NEric Dumazet <edumazet@google.com> Signed-off-by: NDavid S. Miller <davem@davemloft.net>
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由 Fabian Frederick 提交于
ccid_activate is only called by __init ccid_initialize_builtins in same module. Signed-off-by: NFabian Frederick <fabf@skynet.be> Signed-off-by: NDavid S. Miller <davem@davemloft.net>
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由 Fabian Frederick 提交于
dccp_mib_init is only called by __init dccp_init in same module. Signed-off-by: NFabian Frederick <fabf@skynet.be> Signed-off-by: NDavid S. Miller <davem@davemloft.net>
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由 Eric Dumazet 提交于
Lets use a proper structure to clearly document and implement skb fast clones. Then, we might experiment more easily alternative layouts. This patch adds a new skb_fclone_busy() helper, used by tcp and xfrm, to stop leaking of implementation details. Signed-off-by: NEric Dumazet <edumazet@google.com> Signed-off-by: NDavid S. Miller <davem@davemloft.net>
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由 Yuchung Cheng 提交于
Currently we have two different policies for orphan sockets that repeatedly stall on zero window ACKs. If a socket gets a zero window ACK when it is transmitting data, the RTO is used to probe the window. The socket is aborted after roughly tcp_orphan_retries() retries (as in tcp_write_timeout()). But if the socket was idle when it received the zero window ACK, and later wants to send more data, we use the probe timer to probe the window. If the receiver always returns zero window ACKs, icsk_probes keeps getting reset in tcp_ack() and the orphan socket can stall forever until the system reaches the orphan limit (as commented in tcp_probe_timer()). This opens up a simple attack to create lots of hanging orphan sockets to burn the memory and the CPU, as demonstrated in the recent netdev post "TCP connection will hang in FIN_WAIT1 after closing if zero window is advertised." http://www.spinics.net/lists/netdev/msg296539.html This patch follows the design in RTO-based probe: we abort an orphan socket stalling on zero window when the probe timer reaches both the maximum backoff and the maximum RTO. For example, an 100ms RTT connection will timeout after roughly 153 seconds (0.3 + 0.6 + .... + 76.8) if the receiver keeps the window shut. If the orphan socket passes this check, but the system already has too many orphans (as in tcp_out_of_resources()), we still abort it but we'll also send an RST packet as the connection may still be active. In addition, we change TCP_USER_TIMEOUT to cover (life or dead) sockets stalled on zero-window probes. This changes the semantics of TCP_USER_TIMEOUT slightly because it previously only applies when the socket has pending transmission. Signed-off-by: NYuchung Cheng <ycheng@google.com> Signed-off-by: NEric Dumazet <edumazet@google.com> Signed-off-by: NNeal Cardwell <ncardwell@google.com> Reported-by: NAndrey Dmitrov <andrey.dmitrov@oktetlabs.ru> Signed-off-by: NDavid S. Miller <davem@davemloft.net>
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由 Fabian Frederick 提交于
cipso_v4_cache_init is only called by __init cipso_v4_init Signed-off-by: NFabian Frederick <fabf@skynet.be> Signed-off-by: NDavid S. Miller <davem@davemloft.net>
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由 Fabian Frederick 提交于
ip4_frags_ctl_register is only called by __init ipfrag_init Signed-off-by: NFabian Frederick <fabf@skynet.be> Signed-off-by: NDavid S. Miller <davem@davemloft.net>
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由 Fabian Frederick 提交于
tcp_init_mem is only called by __init tcp_init. Signed-off-by: NFabian Frederick <fabf@skynet.be> Signed-off-by: NDavid S. Miller <davem@davemloft.net>
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由 Thierry Reding 提交于
The dsa_switch_suspend() and dsa_switch_resume() functions are only used when PM_SLEEP is enabled, so they need #ifdef CONFIG_PM_SLEEP protection to avoid a compiler warning. Signed-off-by: NThierry Reding <treding@nvidia.com> Acked-by: NFlorian Fainelli <f.fainelli@gmail.com> Signed-off-by: NDavid S. Miller <davem@davemloft.net>
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由 Eric Dumazet 提交于
Proper CHECKSUM_COMPLETE support needs to adjust skb->csum when we remove one header. Its done using skb_gro_postpull_rcsum() In the case of IPv4, we know that the adjustment is not really needed, because the checksum over IPv4 header is 0. Lets add a comment to ease code comprehension and avoid copy/paste errors. Signed-off-by: NEric Dumazet <edumazet@google.com> Signed-off-by: NDavid S. Miller <davem@davemloft.net>
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- 01 10月, 2014 5 次提交
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由 Fabian Frederick 提交于
Commit 3243acd3 ("ieee802154: add __init to lowpan_frags_sysctl_register") added __init to lowpan_frags_ns_sysctl_register instead of lowpan_frags_sysctl_register Suggested-by: NAlexander Aring <alex.aring@gmail.com> Signed-off-by: NFabian Frederick <fabf@skynet.be> Signed-off-by: NDavid S. Miller <davem@davemloft.net>
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由 Li RongQing 提交于
No caller uses the return value, so make this function return void. Signed-off-by: NLi RongQing <roy.qing.li@gmail.com> Signed-off-by: NDavid S. Miller <davem@davemloft.net>
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由 Fabian Frederick 提交于
lowpan_frags_sysctl_register is only called by __init lowpan_net_frag_init (part of the lowpan module). Signed-off-by: NFabian Frederick <fabf@skynet.be> Signed-off-by: NDavid S. Miller <davem@davemloft.net>
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由 Fabian Frederick 提交于
irlan_open is only called by __init irlan_init in same module. Signed-off-by: NFabian Frederick <fabf@skynet.be> Signed-off-by: NDavid S. Miller <davem@davemloft.net>
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由 Florian Westphal 提交于
Eric reports build failure with CONFIG_BRIDGE_NETFILTER=n We insist to build br_nf_core.o unconditionally, but we must only do so if br_netfilter was enabled, else it fails to build due to functions being defined to empty stubs (and some structure members being defined out). Also, BRIDGE_NETFILTER=y|m makes no sense when BRIDGE=n. Fixes: 34666d46 (netfilter: bridge: move br_netfilter out of the core) Reported-by: NEric Dumazet <eric.dumazet@gmail.com> Signed-off-by: NFlorian Westphal <fw@strlen.de> Signed-off-by: NPablo Neira Ayuso <pablo@netfilter.org> Signed-off-by: NDavid S. Miller <davem@davemloft.net>
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- 30 9月, 2014 8 次提交
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由 John Fastabend 提交于
After previous patches to simplify qstats the qstats can be made per cpu with a packed union in Qdisc struct. Signed-off-by: NJohn Fastabend <john.r.fastabend@intel.com> Signed-off-by: NDavid S. Miller <davem@davemloft.net>
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由 John Fastabend 提交于
This removes the use of qstats->qlen variable from the classifiers and makes it an explicit argument to gnet_stats_copy_queue(). The qlen represents the qdisc queue length and is packed into the qstats at the last moment before passnig to user space. By handling it explicitely we avoid, in the percpu stats case, having to figure out which per_cpu variable to put it in. It would probably be best to remove it from qstats completely but qstats is a user space ABI and can't be broken. A future patch could make an internal only qstats structure that would avoid having to allocate an additional u32 variable on the Qdisc struct. This would make the qstats struct 128bits instead of 128+32. Signed-off-by: NJohn Fastabend <john.r.fastabend@intel.com> Signed-off-by: NDavid S. Miller <davem@davemloft.net>
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由 John Fastabend 提交于
This adds helpers to manipulate qstats logic and replaces locations that touch the counters directly. This simplifies future patches to push qstats onto per cpu counters. Signed-off-by: NJohn Fastabend <john.r.fastabend@intel.com> Signed-off-by: NDavid S. Miller <davem@davemloft.net>
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由 John Fastabend 提交于
In order to run qdisc's without locking statistics and estimators need to be handled correctly. To resolve bstats make the statistics per cpu. And because this is only needed for qdiscs that are running without locks which is not the case for most qdiscs in the near future only create percpu stats when qdiscs set the TCQ_F_CPUSTATS flag. Next because estimators use the bstats to calculate packets per second and bytes per second the estimator code paths are updated to use the per cpu statistics. Signed-off-by: NJohn Fastabend <john.r.fastabend@intel.com> Signed-off-by: NDavid S. Miller <davem@davemloft.net>
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由 Florian Westphal 提交于
Suggested by Stephen. Also drop inline keyword and let compiler decide. gcc 4.7.3 decides to no longer inline tcp_ecn_check_ce, so split it up. The actual evaluation is not inlined anymore while the ECN_OK test is. Suggested-by: NStephen Hemminger <stephen@networkplumber.org> Signed-off-by: NDaniel Borkmann <dborkman@redhat.com> Signed-off-by: NFlorian Westphal <fw@strlen.de> Signed-off-by: NDavid S. Miller <davem@davemloft.net>
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由 Florian Westphal 提交于
After Octavian Purdilas tcp ipv4/ipv6 unification work this helper only has a single callsite. While at it, convert name to lowercase, suggested by Stephen. Suggested-by: NStephen Hemminger <stephen@networkplumber.org> Signed-off-by: NDaniel Borkmann <dborkman@redhat.com> Signed-off-by: NFlorian Westphal <fw@strlen.de> Signed-off-by: NDavid S. Miller <davem@davemloft.net>
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由 Li RongQing 提交于
This variable i is overwritten to 0 by following code Signed-off-by: NLi RongQing <roy.qing.li@gmail.com> Signed-off-by: NDavid S. Miller <davem@davemloft.net>
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由 Eric Dumazet 提交于
With proliferation of bit fields in sk_buff, __copy_skb_header() became quite expensive, showing as the most expensive function in a GSO workload. __copy_skb_header() performance is also critical for non GSO TCP operations, as it is used from skb_clone() This patch carefully moves all the fields that were not copied in a separate zone : cloned, nohdr, fclone, peeked, head_frag, xmit_more Then I moved all other fields and all other copied fields in a section delimited by headers_start[0]/headers_end[0] section so that we can use a single memcpy() call, inlined by compiler using long word load/stores. I also tried to make all copies in the natural orders of sk_buff, to help hardware prefetching. I made sure sk_buff size did not change. Signed-off-by: NEric Dumazet <edumazet@google.com> Signed-off-by: NDavid S. Miller <davem@davemloft.net>
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- 29 9月, 2014 15 次提交
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由 Florian Westphal 提交于
Given following iptables ruleset: -P FORWARD DROP -A FORWARD -m sctp --dport 9 -j ACCEPT -A FORWARD -p tcp --dport 80 -j ACCEPT -A FORWARD -p tcp -m conntrack -m state ESTABLISHED,RELATED -j ACCEPT One would assume that this allows SCTP on port 9 and TCP on port 80. Unfortunately, if the SCTP conntrack module is not loaded, this allows *all* SCTP communication, to pass though, i.e. -p sctp -j ACCEPT, which we think is a security issue. This is because on the first SCTP packet on port 9, we create a dummy "generic l4" conntrack entry without any port information (since conntrack doesn't know how to extract this information). All subsequent packets that are unknown will then be in established state since they will fallback to proto_generic and will match the 'generic' entry. Our originally proposed version [1] completely disabled generic protocol tracking, but Jozsef suggests to not track protocols for which a more suitable helper is available, hence we now mitigate the issue for in tree known ct protocol helpers only, so that at least NAT and direction information will still be preserved for others. [1] http://www.spinics.net/lists/netfilter-devel/msg33430.html Joint work with Daniel Borkmann. Signed-off-by: NFlorian Westphal <fw@strlen.de> Signed-off-by: NDaniel Borkmann <dborkman@redhat.com> Acked-by: NJozsef Kadlecsik <kadlec@blackhole.kfki.hu> Signed-off-by: NPablo Neira Ayuso <pablo@netfilter.org>
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由 Arturo Borrero 提交于
We want to know in which cases the user explicitly sets the policy options. In that case, we also want to dump back the info. Signed-off-by: NArturo Borrero Gonzalez <arturo.borrero.glez@gmail.com> Signed-off-by: NPablo Neira Ayuso <pablo@netfilter.org>
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由 Daniel Borkmann 提交于
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: NDaniel Borkmann <dborkman@redhat.com> Signed-off-by: NFlorian Westphal <fw@strlen.de> Signed-off-by: NGlenn Judd <glenn.judd@morganstanley.com> Acked-by: NStephen Hemminger <stephen@networkplumber.org> Signed-off-by: NDavid S. Miller <davem@davemloft.net>
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由 Florian Westphal 提交于
DataCenter TCP (DCTCP) determines cwnd growth based on ECN information and ACK properties, e.g. ACK that updates window is treated differently than DUPACK. Also DCTCP needs information whether ACK was delayed ACK. Furthermore, DCTCP also implements a CE state machine that keeps track of CE markings of incoming packets. Therefore, extend the congestion control framework to provide these event types, so that DCTCP can be properly implemented as a normal congestion algorithm module outside of the core stack. Joint work with Daniel Borkmann and Glenn Judd. Signed-off-by: NFlorian Westphal <fw@strlen.de> Signed-off-by: NDaniel Borkmann <dborkman@redhat.com> Signed-off-by: NGlenn Judd <glenn.judd@morganstanley.com> Acked-by: NStephen Hemminger <stephen@networkplumber.org> Signed-off-by: NDavid S. Miller <davem@davemloft.net>
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由 Florian Westphal 提交于
The congestion control ops "cwnd_event" currently supports CA_EVENT_FAST_ACK and CA_EVENT_SLOW_ACK events (among others). Both FAST and SLOW_ACK are only used by Westwood congestion control algorithm. This removes both flags from cwnd_event and adds a new in_ack_event callback for this. The goal is to be able to provide more detailed information about ACKs, such as whether ECE flag was set, or whether the ACK resulted in a window update. It is required for DataCenter TCP (DCTCP) congestion control algorithm as it makes a different choice depending on ECE being set or not. Joint work with Daniel Borkmann and Glenn Judd. Signed-off-by: NFlorian Westphal <fw@strlen.de> Signed-off-by: NDaniel Borkmann <dborkman@redhat.com> Signed-off-by: NGlenn Judd <glenn.judd@morganstanley.com> Acked-by: NStephen Hemminger <stephen@networkplumber.org> Signed-off-by: NDavid S. Miller <davem@davemloft.net>
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由 Daniel Borkmann 提交于
This patch adds a flag to TCP congestion algorithms that allows for requesting to mark IPv4/IPv6 sockets with transport as ECN capable, that is, ECT(0), when required by a congestion algorithm. It is currently used and needed in DataCenter TCP (DCTCP), as it requires both peers to assert ECT on all IP packets sent - it uses ECN feedback (i.e. CE, Congestion Encountered information) from switches inside the data center to derive feedback to the end hosts. Therefore, simply add a new flag to icsk_ca_ops. Note that DCTCP's algorithm/behaviour slightly diverges from RFC3168, therefore this is only (!) enabled iff the assigned congestion control ops module has requested this. By that, we can tightly couple this logic really only to the provided congestion control ops. Joint work with Florian Westphal and Glenn Judd. Signed-off-by: NDaniel Borkmann <dborkman@redhat.com> Signed-off-by: NFlorian Westphal <fw@strlen.de> Signed-off-by: NGlenn Judd <glenn.judd@morganstanley.com> Acked-by: NStephen Hemminger <stephen@networkplumber.org> Signed-off-by: NDavid S. Miller <davem@davemloft.net>
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由 Florian Westphal 提交于
Split assignment and initialization from one into two functions. This is required by followup patches that add Datacenter TCP (DCTCP) congestion control algorithm - we need to be able to determine if the connection is moderated by DCTCP before the 3WHS has finished. As we walk the available congestion control list during the assignment, we are always guaranteed to have Reno present as it's fixed compiled-in. Therefore, since we're doing the early assignment, we don't have a real use for the Reno alias tcp_init_congestion_ops anymore and can thus remove it. Actual usage of the congestion control operations are being made after the 3WHS has finished, in some cases however we can access get_info() via diag if implemented, therefore we need to zero out the private area for those modules. Joint work with Daniel Borkmann and Glenn Judd. Signed-off-by: NFlorian Westphal <fw@strlen.de> Signed-off-by: NDaniel Borkmann <dborkman@redhat.com> Signed-off-by: NGlenn Judd <glenn.judd@morganstanley.com> Acked-by: NStephen Hemminger <stephen@networkplumber.org> Signed-off-by: NDavid S. Miller <davem@davemloft.net>
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由 John Fastabend 提交于
This completes the cls_rsvp conversion to RCU safe copy, update semantics. As a result all cases of tcf_exts_change occur on empty lists now. Signed-off-by: NJohn Fastabend <john.r.fastabend@intel.com> Signed-off-by: NDavid S. Miller <davem@davemloft.net>
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由 WANG Cong 提交于
Clearly the following change is not expected: - if (!cp.perfect && !cp.h) - cp.alloc_hash = cp.hash; + if (!cp->perfect && cp->h) + cp->alloc_hash = cp->hash; Fixes: commit 331b7292 ("net: sched: RCU cls_tcindex") Cc: John Fastabend <john.fastabend@gmail.com> Signed-off-by: NCong Wang <xiyou.wangcong@gmail.com> Acked-by: NJohn Fastabend <john.r.fastabend@intel.com> Signed-off-by: NDavid S. Miller <davem@davemloft.net>
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由 WANG Cong 提交于
When kmemdup() fails, we should return -ENOMEM. Cc: John Fastabend <john.fastabend@gmail.com> Signed-off-by: NCong Wang <xiyou.wangcong@gmail.com> Acked-by: NJohn Fastabend <john.r.fastabend@intel.com> Signed-off-by: NDavid S. Miller <davem@davemloft.net>
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由 Rick Jones 提交于
We do not wish to disturb dropwatch or perf drop profiles with an ARP we will ignore. Signed-off-by: NRick Jones <rick.jones2@hp.com> Signed-off-by: NDavid S. Miller <davem@davemloft.net>
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由 WANG Cong 提交于
Cc: Jamal Hadi Salim <jhs@mojatatu.com> Signed-off-by: NCong Wang <xiyou.wangcong@gmail.com> Acked-by: NJamal Hadi Salim <hadi@mojatatu.com> Signed-off-by: NDavid S. Miller <davem@davemloft.net>
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由 Florian Fainelli 提交于
Allow switches driver to query and enable/disable EEE on a per-port basis by implementing the ethtool_{get,set}_eee settings and delegating these operations to the switch driver. set_eee() will need to coordinate with the PHY driver to make sure that EEE is enabled, the link-partner supports it and the auto-negotiation result is satisfactory. Signed-off-by: NFlorian Fainelli <f.fainelli@gmail.com> Signed-off-by: NDavid S. Miller <davem@davemloft.net>
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由 Florian Fainelli 提交于
Whenever a per-port network device is used/unused, invoke the switch driver port_enable/port_disable callbacks to allow saving as much power as possible by disabling unused parts of the switch (RX/TX logic, memory arrays, PHYs...). We supply a PHY device argument to make sure the switch driver can act on the PHY device if needed (like putting/taking the PHY out of deep low power mode). Signed-off-by: NFlorian Fainelli <f.fainelli@gmail.com> Signed-off-by: NDavid S. Miller <davem@davemloft.net>
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由 Florian Fainelli 提交于
dsa_slave_open() should start the PHY library state machine for its PHY interface, and dsa_slave_close() should stop the PHY library state machine accordingly. Signed-off-by: NFlorian Fainelli <f.fainelli@gmail.com> Signed-off-by: NDavid S. Miller <davem@davemloft.net>
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