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2019-06-12tcp: add optional per socket transmit delayEric Dumazet
Adding delays to TCP flows is crucial for studying behavior of TCP stacks, including congestion control modules. Linux offers netem module, but it has unpractical constraints : - Need root access to change qdisc - Hard to setup on egress if combined with non trivial qdisc like FQ - Single delay for all flows. EDT (Earliest Departure Time) adoption in TCP stack allows us to enable a per socket delay at a very small cost. Networking tools can now establish thousands of flows, each of them with a different delay, simulating real world conditions. This requires FQ packet scheduler or a EDT-enabled NIC. This patchs adds TCP_TX_DELAY socket option, to set a delay in usec units. unsigned int tx_delay = 10000; /* 10 msec */ setsockopt(fd, SOL_TCP, TCP_TX_DELAY, &tx_delay, sizeof(tx_delay)); Note that FQ packet scheduler limits might need some tweaking : man tc-fq PARAMETERS limit Hard limit on the real queue size. When this limit is reached, new packets are dropped. If the value is lowered, packets are dropped so that the new limit is met. Default is 10000 packets. flow_limit Hard limit on the maximum number of packets queued per flow. Default value is 100. Use of TCP_TX_DELAY option will increase number of skbs in FQ qdisc, so packets would be dropped if any of the previous limit is hit. Use of a jump label makes this support runtime-free, for hosts never using the option. Also note that TSQ (TCP Small Queues) limits are slightly changed with this patch : we need to account that skbs artificially delayed wont stop us providind more skbs to feed the pipe (netem uses skb_orphan_partial() for this purpose, but FQ can not use this trick) Because of that, using big delays might very well trigger old bugs in TSO auto defer logic and/or sndbuf limited detection. Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2019-06-07Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/netDavid S. Miller
Some ISDN files that got removed in net-next had some changes done in mainline, take the removals. Signed-off-by: David S. Miller <davem@davemloft.net>
2019-05-30tcp: add support to TCP_FASTOPEN_KEY for optional backup keyJason Baron
Add support for get/set of an optional backup key via TCP_FASTOPEN_KEY, in addition to the current 'primary' key. The primary key is used to encrypt and decrypt TFO cookies, while the backup is only used to decrypt TFO cookies. The backup key is used to maximize successful TFO connections when TFO keys are rotated. Currently, TCP_FASTOPEN_KEY allows a single 16-byte primary key to be set. This patch now allows a 32-byte value to be set, where the first 16 bytes are used as the primary key and the second 16 bytes are used for the backup key. Similarly, for getsockopt(), we can receive a 32-byte value as output if requested. If a 16-byte value is used to set the primary key via TCP_FASTOPEN_KEY, then any previously set backup key will be removed. Signed-off-by: Jason Baron <jbaron@akamai.com> Signed-off-by: Christoph Paasch <cpaasch@apple.com> Acked-by: Yuchung Cheng <ycheng@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2019-05-30tcp: add backup TFO key infrastructureJason Baron
We would like to be able to rotate TFO keys while minimizing the number of client cookies that are rejected. Currently, we have only one key which can be used to generate and validate cookies, thus if we simply replace this key clients can easily have cookies rejected upon rotation. We propose having the ability to have both a primary key and a backup key. The primary key is used to generate as well as to validate cookies. The backup is only used to validate cookies. Thus, keys can be rotated as: 1) generate new key 2) add new key as the backup key 3) swap the primary and backup key, thus setting the new key as the primary We don't simply set the new key as the primary key and move the old key to the backup slot because the ip may be behind a load balancer and we further allow for the fact that all machines behind the load balancer will not be updated simultaneously. We make use of this infrastructure in subsequent patches. Suggested-by: Igor Lubashev <ilubashe@akamai.com> Signed-off-by: Jason Baron <jbaron@akamai.com> Signed-off-by: Christoph Paasch <cpaasch@apple.com> Acked-by: Yuchung Cheng <ycheng@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2019-05-30treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 152Thomas Gleixner
Based on 1 normalized pattern(s): this program is free software you can redistribute it and or modify it under the terms of the gnu general public license as published by the free software foundation either version 2 of the license or at your option any later version extracted by the scancode license scanner the SPDX license identifier GPL-2.0-or-later has been chosen to replace the boilerplate/reference in 3029 file(s). Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Allison Randal <allison@lohutok.net> Cc: linux-spdx@vger.kernel.org Link: https://lkml.kernel.org/r/20190527070032.746973796@linutronix.de Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-05-15tcp: do not recycle cloned skbsEric Dumazet
It is illegal to change arbitrary fields in skb_shared_info if the skb is cloned. Before calling skb_zcopy_clear() we need to ensure this rule, therefore we need to move the test from sk_stream_alloc_skb() to sk_wmem_free_skb() Fixes: 4f661542a402 ("tcp: fix zerocopy and notsent_lowat issues") Signed-off-by: Eric Dumazet <edumazet@google.com> Diagnosed-by: Willem de Bruijn <willemb@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2019-05-01tcp: refactor setting the initial congestion windowYuchung Cheng
Relocate the congestion window initialization from tcp_init_metrics() to tcp_init_transfer() to improve code readability. Signed-off-by: Yuchung Cheng <ycheng@google.com> Signed-off-by: Neal Cardwell <ncardwell@google.com> Signed-off-by: Soheil Hassas Yeganeh <soheil@google.com> Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2019-04-19tcp: properly reset skb->truesize for tx recyclingEric Dumazet
tcp sendmsg() and sendpage() normally advance skb->data_len and skb->truesize by the payload added to an skb. But sendmsg(fd, ..., MSG_ZEROCOPY) has to account for whole pages, even if a single byte of payload is used in the page. This means that we can not assume skb->truesize can be adjusted by skb->data_len. We must instead overwrite its value. Otherwise skb->truesize is too big and can hit socket sndbuf limit, especially if the skb is recycled multiple times :/ Fixes: 472c2e07eef0 ("tcp: add one skb cache for tx") Signed-off-by: Eric Dumazet <edumazet@google.com> Cc: Soheil Hassas Yeganeh <soheil@google.com> Cc: Willem de Bruijn <willemb@google.com> Acked-by: Soheil Hassas Yeganeh <soheil@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2019-03-29tcp: cleanup sk_tx_skb_cache before reuseEric Dumazet
TCP stack relies on the fact that a freshly allocated skb has skb->cb[] and skb_shinfo(skb)->tx_flags cleared. When recycling tx skb, we must ensure these fields are cleared. Fixes: 472c2e07eef0 ("tcp: add one skb cache for tx") Signed-off-by: Eric Dumazet <edumazet@google.com> Cc: Soheil Hassas Yeganeh <soheil@google.com> Cc: Willem de Bruijn <willemb@google.com> Acked-by: Soheil Hassas Yeganeh <soheil@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2019-03-27tcp: fix zerocopy and notsent_lowat issuesEric Dumazet
My recent patch had at least three problems : 1) TX zerocopy wants notification when skb is acknowledged, thus we need to call skb_zcopy_clear() if the skb is cached into sk->sk_tx_skb_cache 2) Some applications might expect precise EPOLLOUT notifications, so we need to update sk->sk_wmem_queued and call sk_mem_uncharge() from sk_wmem_free_skb() in all cases. The SOCK_QUEUE_SHRUNK flag must also be set. 3) Reuse of saved skb should have used skb_cloned() instead of simply checking if the fast clone has been freed. Fixes: 472c2e07eef0 ("tcp: add one skb cache for tx") Signed-off-by: Eric Dumazet <edumazet@google.com> Cc: Willem de Bruijn <willemb@google.com> Cc: Soheil Hassas Yeganeh <soheil@google.com> Acked-by: Soheil Hassas Yeganeh <soheil@google.com> Tested-by: Holger Hoffstätte <holger@applied-asynchrony.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2019-03-23tcp: add one skb cache for rxEric Dumazet
Often times, recvmsg() system calls and BH handling for a particular TCP socket are done on different cpus. This means the incoming skb had to be allocated on a cpu, but freed on another. This incurs a high spinlock contention in slab layer for small rpc, but also a high number of cache line ping pongs for larger packets. A full size GRO packet might use 45 page fragments, meaning that up to 45 put_page() can be involved. More over performing the __kfree_skb() in the recvmsg() context adds a latency for user applications, and increase probability of trapping them in backlog processing, since the BH handler might found the socket owned by the user. This patch, combined with the prior one increases the rpc performance by about 10 % on servers with large number of cores. (tcp_rr workload with 10,000 flows and 112 threads reach 9 Mpps instead of 8 Mpps) This also increases single bulk flow performance on 40Gbit+ links, since in this case there are often two cpus working in tandem : - CPU handling the NIC rx interrupts, feeding the receive queue, and (after this patch) freeing the skbs that were consumed. - CPU in recvmsg() system call, essentially 100 % busy copying out data to user space. Having at most one skb in a per-socket cache has very little risk of memory exhaustion, and since it is protected by socket lock, its management is essentially free. Note that if rps/rfs is used, we do not enable this feature, because there is high chance that the same cpu is handling both the recvmsg() system call and the TCP rx path, but that another cpu did the skb allocations in the device driver right before the RPS/RFS logic. To properly handle this case, it seems we would need to record on which cpu skb was allocated, and use a different channel to give skbs back to this cpu. Signed-off-by: Eric Dumazet <edumazet@google.com> Acked-by: Soheil Hassas Yeganeh <soheil@google.com> Acked-by: Willem de Bruijn <willemb@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2019-03-23tcp: add one skb cache for txEric Dumazet
On hosts with a lot of cores, RPC workloads suffer from heavy contention on slab spinlocks. 20.69% [kernel] [k] queued_spin_lock_slowpath 5.64% [kernel] [k] _raw_spin_lock 3.83% [kernel] [k] syscall_return_via_sysret 3.48% [kernel] [k] __entry_text_start 1.76% [kernel] [k] __netif_receive_skb_core 1.64% [kernel] [k] __fget For each sendmsg(), we allocate one skb, and free it at the time ACK packet comes. In many cases, ACK packets are handled by another cpus, and this unfortunately incurs heavy costs for slab layer. This patch uses an extra pointer in socket structure, so that we try to reuse the same skb and avoid these expensive costs. We cache at most one skb per socket so this should be safe as far as memory pressure is concerned. Signed-off-by: Eric Dumazet <edumazet@google.com> Acked-by: Soheil Hassas Yeganeh <soheil@google.com> Acked-by: Willem de Bruijn <willemb@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2019-03-06tcp: do not report TCP_CM_INQ of 0 for closed connectionsSoheil Hassas Yeganeh
Returning 0 as inq to userspace indicates there is no more data to read, and the application needs to wait for EPOLLIN. For a connection that has received FIN from the remote peer, however, the application must continue reading until getting EOF (return value of 0 from tcp_recvmsg) or an error, if edge-triggered epoll (EPOLLET) is being used. Otherwise, the application will never receive a new EPOLLIN, since there is no epoll edge after the FIN. Return 1 when there is no data left on the queue but the connection has received FIN, so that the applications continue reading. Fixes: b75eba76d3d72 (tcp: send in-queue bytes in cmsg upon read) Signed-off-by: Soheil Hassas Yeganeh <soheil@google.com> Acked-by: Neal Cardwell <ncardwell@google.com> Signed-off-by: Eric Dumazet <edumazet@google.com> Acked-by: Yuchung Cheng <ycheng@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2019-03-06tcp: detecting the misuse of .sendpage for Slab objectsVasily Averin
sendpage was not designed for processing of the Slab pages, in some situations it can trigger BUG_ON on receiving side. Signed-off-by: Vasily Averin <vvs@virtuozzo.com> Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2019-02-26tcp: convert tcp_md5_needed to static_branch APIEric Dumazet
We prefer static_branch_unlikely() over static_key_false() these days. Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2019-02-26tcp: get rid of tcp_check_send_head()Eric Dumazet
This helper is used only once, and its name is no longer relevant. Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2019-02-20Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/netDavid S. Miller
Two easily resolvable overlapping change conflicts, one in TCP and one in the eBPF verifier. Signed-off-by: David S. Miller <davem@davemloft.net>
2019-02-17tcp: clear icsk_backoff in tcp_write_queue_purge()Eric Dumazet
soukjin bae reported a crash in tcp_v4_err() handling ICMP_DEST_UNREACH after tcp_write_queue_head(sk) returned a NULL pointer. Current logic should have prevented this : if (seq != tp->snd_una || !icsk->icsk_retransmits || !icsk->icsk_backoff || fastopen) break; Problem is the write queue might have been purged and icsk_backoff has not been cleared. Signed-off-by: Eric Dumazet <edumazet@google.com> Reported-by: soukjin bae <soukjin.bae@samsung.com> Acked-by: Neal Cardwell <ncardwell@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2019-02-03socket: Add SO_TIMESTAMPING_NEWDeepa Dinamani
Add SO_TIMESTAMPING_NEW variant of socket timestamp options. This is the y2038 safe versions of the SO_TIMESTAMPING_OLD for all architectures. Signed-off-by: Deepa Dinamani <deepa.kernel@gmail.com> Acked-by: Willem de Bruijn <willemb@google.com> Cc: chris@zankel.net Cc: fenghua.yu@intel.com Cc: rth@twiddle.net Cc: tglx@linutronix.de Cc: ubraun@linux.ibm.com Cc: linux-alpha@vger.kernel.org Cc: linux-arch@vger.kernel.org Cc: linux-ia64@vger.kernel.org Cc: linux-mips@linux-mips.org Cc: linux-s390@vger.kernel.org Cc: linux-xtensa@linux-xtensa.org Cc: sparclinux@vger.kernel.org Signed-off-by: David S. Miller <davem@davemloft.net>
2019-02-03socket: Add SO_TIMESTAMP[NS]_NEWDeepa Dinamani
Add SO_TIMESTAMP_NEW and SO_TIMESTAMPNS_NEW variants of socket timestamp options. These are the y2038 safe versions of the SO_TIMESTAMP_OLD and SO_TIMESTAMPNS_OLD for all architectures. Note that the format of scm_timestamping.ts[0] is not changed in this patch. Signed-off-by: Deepa Dinamani <deepa.kernel@gmail.com> Acked-by: Willem de Bruijn <willemb@google.com> Cc: jejb@parisc-linux.org Cc: ralf@linux-mips.org Cc: rth@twiddle.net Cc: linux-alpha@vger.kernel.org Cc: linux-mips@linux-mips.org Cc: linux-parisc@vger.kernel.org Cc: linux-rdma@vger.kernel.org Cc: netdev@vger.kernel.org Cc: sparclinux@vger.kernel.org Signed-off-by: David S. Miller <davem@davemloft.net>
2019-02-03socket: Use old_timeval types for socket timestampsDeepa Dinamani
As part of y2038 solution, all internal uses of struct timeval are replaced by struct __kernel_old_timeval and struct compat_timeval by struct old_timeval32. Make socket timestamps use these new types. This is mainly to be able to verify that the kernel build is y2038 safe when such non y2038 safe types are not supported anymore. Signed-off-by: Deepa Dinamani <deepa.kernel@gmail.com> Acked-by: Willem de Bruijn <willemb@google.com> Cc: isdn@linux-pingi.de Signed-off-by: David S. Miller <davem@davemloft.net>
2019-02-03sockopt: Rename SO_TIMESTAMP* to SO_TIMESTAMP*_OLDDeepa Dinamani
SO_TIMESTAMP, SO_TIMESTAMPNS and SO_TIMESTAMPING options, the way they are currently defined, are not y2038 safe. Subsequent patches in the series add new y2038 safe versions of these options which provide 64 bit timestamps on all architectures uniformly. Hence, rename existing options with OLD tag suffixes. Also note that kernel will not use the untagged SO_TIMESTAMP* and SCM_TIMESTAMP* options internally anymore. Signed-off-by: Deepa Dinamani <deepa.kernel@gmail.com> Acked-by: Willem de Bruijn <willemb@google.com> Cc: deller@gmx.de Cc: dhowells@redhat.com Cc: jejb@parisc-linux.org Cc: ralf@linux-mips.org Cc: rth@twiddle.net Cc: linux-afs@lists.infradead.org Cc: linux-alpha@vger.kernel.org Cc: linux-arch@vger.kernel.org Cc: linux-mips@linux-mips.org Cc: linux-parisc@vger.kernel.org Cc: linux-rdma@vger.kernel.org Cc: sparclinux@vger.kernel.org Signed-off-by: David S. Miller <davem@davemloft.net>
2019-01-27tcp: Refactor pingpong codeWei Wang
Instead of using pingpong as a single bit information, we refactor the code to treat it as a counter. When interactive session is detected, we set pingpong count to TCP_PINGPONG_THRESH. And when pingpong count is >= TCP_PINGPONG_THRESH, we consider the session in pingpong mode. This patch is a pure refactor and sets foundation for the next patch. This patch itself does not change any pingpong logic. Signed-off-by: Wei Wang <weiwan@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>
2019-01-25tcp: allow zerocopy with fastopenWillem de Bruijn
Accept MSG_ZEROCOPY in all the TCP states that allow sendmsg. Remove the explicit check for ESTABLISHED and CLOSE_WAIT states. This requires correctly handling zerocopy state (uarg, sk_zckey) in all paths reachable from other TCP states. Such as the EPIPE case in sk_stream_wait_connect, which a sendmsg() in incorrect state will now hit. Most paths are already safe. Only extension needed is for TCP Fastopen active open. This can build an skb with data in tcp_send_syn_data. Pass the uarg along with other fastopen state, so that this skb also generates a zerocopy notification on release. Tested with active and passive tcp fastopen packetdrill scripts at https://github.com/wdebruij/packetdrill/commit/1747eef03d25a2404e8132817d0f1244fd6f129d Signed-off-by: Willem de Bruijn <willemb@google.com> Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2019-01-21Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/netDavid S. Miller
Completely minor snmp doc conflict. Signed-off-by: David S. Miller <davem@davemloft.net>
2019-01-17tcp: move rx_opt & syn_data_acked init to tcp_disconnect()Eric Dumazet
If we make sure all listeners have these fields cleared, then a clone will also inherit zero values. Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2019-01-17tcp: move tp->rack init to tcp_disconnect()Eric Dumazet
If we make sure all listeners have proper tp->rack value, then a clone will also inherit proper initial value. Note that fresh sockets init tp->rack from tcp_init_sock() Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2019-01-17tcp: move app_limited init to tcp_disconnect()Eric Dumazet
If we make sure all listeners have app_limited set to ~0U, then a clone will also inherit proper initial value. Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2019-01-17tcp: move retrans_out, sacked_out, tlp_high_seq, last_oow_ack_time init to ↵Eric Dumazet
tcp_disconnect() If we make sure all listeners have these fields cleared, then a clone will also inherit zero values. Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2019-01-17tcp: move snd_cwnd & snd_cwnd_cnt init to tcp_disconnect()Eric Dumazet
Passive connections can inherit proper value by cloning, if we make sure all listeners have the proper values there. tcp_disconnect() was setting snd_cwnd to 2, which seems quite obsolete since IW10 adoption. Also remove an obsolete comment. Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2019-01-17tcp: move mdev_us init to tcp_disconnect()Eric Dumazet
If we make sure a listener always has its mdev_us field set to TCP_TIMEOUT_INIT, we do not need to rewrite this field after a new clone is created. tcp_disconnect() is very seldom used in real applications. Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2019-01-17tcp: move icsk_rto init to tcp_disconnect()Eric Dumazet
If we make sure a listener always has its icsk_rto field set to TCP_TIMEOUT_INIT, we do not need to rewrite this field after a new clone is created. tcp_disconnect() is very seldom used in real applications. Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2019-01-15tcp: allow MSG_ZEROCOPY transmission also in CLOSE_WAIT stateWillem de Bruijn
TCP transmission with MSG_ZEROCOPY fails if the peer closes its end of the connection and so transitions this socket to CLOSE_WAIT state. Transmission in close wait state is acceptable. Other similar tests in the stack (e.g., in FastOpen) accept both states. Relax this test, too. Link: https://www.mail-archive.com/netdev@vger.kernel.org/msg276886.html Link: https://www.mail-archive.com/netdev@vger.kernel.org/msg227390.html Fixes: f214f915e7db ("tcp: enable MSG_ZEROCOPY") Reported-by: Marek Majkowski <marek@cloudflare.com> Signed-off-by: Willem de Bruijn <willemb@google.com> CC: Yuchung Cheng <ycheng@google.com> CC: Neal Cardwell <ncardwell@google.com> CC: Soheil Hassas Yeganeh <soheil@google.com> CC: Alexey Kodanev <alexey.kodanev@oracle.com> Acked-by: Soheil Hassas Yeganeh <soheil@google.com> Reviewed-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2018-12-06tcp: fix code style in tcp_recvmsg()Pedro Tammela
2 goto labels are indented with a tab. remove the tabs and keep the code style consistent. Signed-off-by: Pedro Tammela <pctammela@gmail.com> Acked-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2018-12-03udp: elide zerocopy operation in hot pathWillem de Bruijn
With MSG_ZEROCOPY, each skb holds a reference to a struct ubuf_info. Release of its last reference triggers a completion notification. The TCP stack in tcp_sendmsg_locked holds an extra ref independent of the skbs, because it can build, send and free skbs within its loop, possibly reaching refcount zero and freeing the ubuf_info too soon. The UDP stack currently also takes this extra ref, but does not need it as all skbs are sent after return from __ip(6)_append_data. Avoid the extra refcount_inc and refcount_dec_and_test, and generally the sock_zerocopy_put in the common path, by passing the initial reference to the first skb. This approach is taken instead of initializing the refcount to 0, as that would generate error "refcount_t: increment on 0" on the next skb_zcopy_set. Changes v3 -> v4 - Move skb_zcopy_set below the only kfree_skb that might cause a premature uarg destroy before skb_zerocopy_put_abort - Move the entire skb_shinfo assignment block, to keep that cacheline access in one place Signed-off-by: Willem de Bruijn <willemb@google.com> Acked-by: Paolo Abeni <pabeni@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2018-11-30tcp: md5: add tcp_md5_needed jump labelEric Dumazet
Most linux hosts never setup TCP MD5 keys. We can avoid a cache line miss (accessing tp->md5ig_info) on RX and TX using a jump label. Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2018-11-17tcp: add SRTT to SCM_TIMESTAMPING_OPT_STATSYousuk Seung
Add TCP_NLA_SRTT to SCM_TIMESTAMPING_OPT_STATS that reports the smoothed round trip time in microseconds (tcp_sock.srtt_us >> 3). Signed-off-by: Yousuk Seung <ysseung@google.com> Signed-off-by: Eric Dumazet <edumazet@google.com> Acked-by: Soheil Hassas Yeganeh <soheil@google.com> Acked-by: Neal Cardwell <ncardwell@google.com> Acked-by: Yuchung Cheng <ycheng@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2018-11-16tcp: clean up STATE_TRACEYafang Shao
Currently we can use bpf or tcp tracepoint to conveniently trace the tcp state transition at the run time. So we don't need to do this stuff at the compile time anymore. Signed-off-by: Yafang Shao <laoar.shao@gmail.com> Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2018-10-31mm: remove include/linux/bootmem.hMike Rapoport
Move remaining definitions and declarations from include/linux/bootmem.h into include/linux/memblock.h and remove the redundant header. The includes were replaced with the semantic patch below and then semi-automated removal of duplicated '#include <linux/memblock.h> @@ @@ - #include <linux/bootmem.h> + #include <linux/memblock.h> [sfr@canb.auug.org.au: dma-direct: fix up for the removal of linux/bootmem.h] Link: http://lkml.kernel.org/r/20181002185342.133d1680@canb.auug.org.au [sfr@canb.auug.org.au: powerpc: fix up for removal of linux/bootmem.h] Link: http://lkml.kernel.org/r/20181005161406.73ef8727@canb.auug.org.au [sfr@canb.auug.org.au: x86/kaslr, ACPI/NUMA: fix for linux/bootmem.h removal] Link: http://lkml.kernel.org/r/20181008190341.5e396491@canb.auug.org.au Link: http://lkml.kernel.org/r/1536927045-23536-30-git-send-email-rppt@linux.vnet.ibm.com Signed-off-by: Mike Rapoport <rppt@linux.vnet.ibm.com> Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au> Acked-by: Michal Hocko <mhocko@suse.com> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Chris Zankel <chris@zankel.net> Cc: "David S. Miller" <davem@davemloft.net> Cc: Geert Uytterhoeven <geert@linux-m68k.org> Cc: Greentime Hu <green.hu@gmail.com> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Guan Xuetao <gxt@pku.edu.cn> Cc: Ingo Molnar <mingo@redhat.com> Cc: "James E.J. Bottomley" <jejb@parisc-linux.org> Cc: Jonas Bonn <jonas@southpole.se> Cc: Jonathan Corbet <corbet@lwn.net> Cc: Ley Foon Tan <lftan@altera.com> Cc: Mark Salter <msalter@redhat.com> Cc: Martin Schwidefsky <schwidefsky@de.ibm.com> Cc: Matt Turner <mattst88@gmail.com> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: Michal Simek <monstr@monstr.eu> Cc: Palmer Dabbelt <palmer@sifive.com> Cc: Paul Burton <paul.burton@mips.com> Cc: Richard Kuo <rkuo@codeaurora.org> Cc: Richard Weinberger <richard@nod.at> Cc: Rich Felker <dalias@libc.org> Cc: Russell King <linux@armlinux.org.uk> Cc: Serge Semin <fancer.lancer@gmail.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Tony Luck <tony.luck@intel.com> Cc: Vineet Gupta <vgupta@synopsys.com> Cc: Yoshinori Sato <ysato@users.sourceforge.jp> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-10-23Revert "net: simplify sock_poll_wait"Karsten Graul
This reverts commit dd979b4df817e9976f18fb6f9d134d6bc4a3c317. This broke tcp_poll for SMC fallback: An AF_SMC socket establishes an internal TCP socket for the initial handshake with the remote peer. Whenever the SMC connection can not be established this TCP socket is used as a fallback. All socket operations on the SMC socket are then forwarded to the TCP socket. In case of poll, the file->private_data pointer references the SMC socket because the TCP socket has no file assigned. This causes tcp_poll to wait on the wrong socket. Signed-off-by: Karsten Graul <kgraul@linux.ibm.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2018-10-15net: extend sk_pacing_rate to unsigned longEric Dumazet
sk_pacing_rate has beed introduced as a u32 field in 2013, effectively limiting per flow pacing to 34Gbit. We believe it is time to allow TCP to pace high speed flows on 64bit hosts, as we now can reach 100Gbit on one TCP flow. This patch adds no cost for 32bit kernels. The tcpi_pacing_rate and tcpi_max_pacing_rate were already exported as 64bit, so iproute2/ss command require no changes. Unfortunately the SO_MAX_PACING_RATE socket option will stay 32bit and we will need to add a new option to let applications control high pacing rates. State Recv-Q Send-Q Local Address:Port Peer Address:Port ESTAB 0 1787144 10.246.9.76:49992 10.246.9.77:36741 timer:(on,003ms,0) ino:91863 sk:2 <-> skmem:(r0,rb540000,t66440,tb2363904,f605944,w1822984,o0,bl0,d0) ts sack bbr wscale:8,8 rto:201 rtt:0.057/0.006 mss:1448 rcvmss:536 advmss:1448 cwnd:138 ssthresh:178 bytes_acked:256699822585 segs_out:177279177 segs_in:3916318 data_segs_out:177279175 bbr:(bw:31276.8Mbps,mrtt:0,pacing_gain:1.25,cwnd_gain:2) send 28045.5Mbps lastrcv:73333 pacing_rate 38705.0Mbps delivery_rate 22997.6Mbps busy:73333ms unacked:135 retrans:0/157 rcv_space:14480 notsent:2085120 minrtt:0.013 Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2018-10-02tcp: do not release socket ownership in tcp_close()Eric Dumazet
syzkaller was able to hit the WARN_ON(sock_owned_by_user(sk)); in tcp_close() While a socket is being closed, it is very possible other threads find it in rtnetlink dump. tcp_get_info() will acquire the socket lock for a short amount of time (slow = lock_sock_fast(sk)/unlock_sock_fast(sk, slow);), enough to trigger the warning. Fixes: 67db3e4bfbc9 ("tcp: no longer hold ehash lock while calling tcp_get_info()") Signed-off-by: Eric Dumazet <edumazet@google.com> Reported-by: syzbot <syzkaller@googlegroups.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2018-10-01tcp: adjust rcv zerocopy hints based on frag sizesSoheil Hassas Yeganeh
When SKBs are coalesced, we can have SKBs with different frag sizes. Some with PAGE_SIZE and some not with PAGE_SIZE. Since recv_skip_hint is always set to the full SKB size, it can overestimate the amount that should be read using normal read for coalesced packets. Change the recv_skip_hint so that it only includes the first frags that are not of PAGE_SIZE. Signed-off-by: Soheil Hassas Yeganeh <soheil@google.com> Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2018-10-01tcp: set recv_skip_hint when tcp_inq is less than PAGE_SIZESoheil Hassas Yeganeh
When we have less than PAGE_SIZE of data on receive queue, we set recv_skip_hint to 0. Instead, set it to the actual number of bytes available. Signed-off-by: Soheil Hassas Yeganeh <soheil@google.com> Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2018-09-29tcp: up initial rmem to 128KB and SYN rwin to around 64KBYuchung Cheng
Previously TCP initial receive buffer is ~87KB by default and the initial receive window is ~29KB (20 MSS). This patch changes the two numbers to 128KB and ~64KB (rounding down to the multiples of MSS) respectively. The patch also simplifies the calculations s.t. the two numbers are directly controlled by sysctl tcp_rmem[1]: 1) Initial receiver buffer budget (sk_rcvbuf): while this should be configured via sysctl tcp_rmem[1], previously tcp_fixup_rcvbuf() always override and set a larger size when a new connection establishes. 2) Initial receive window in SYN: previously it is set to 20 packets if MSS <= 1460. The number 20 was based on the initial congestion window of 10: the receiver needs twice amount to avoid being limited by the receive window upon out-of-order delivery in the first window burst. But since this only applies if the receiving MSS <= 1460, connection using large MTU (e.g. to utilize receiver zero-copy) may be limited by the receive window. With this patch TCP memory configuration is more straight-forward and more properly sized to modern high-speed networks by default. Several popular stacks have been announcing 64KB rwin in SYNs as well. Signed-off-by: Yuchung Cheng <ycheng@google.com> Signed-off-by: Wei Wang <weiwan@google.com> Signed-off-by: Neal Cardwell <ncardwell@google.com> Signed-off-by: Eric Dumazet <edumazet@google.com> Reviewed-by: Soheil Hassas Yeganeh <soheil@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2018-09-21tcp: provide earliest departure time in skb->tstampEric Dumazet
Switch internal TCP skb->skb_mstamp to skb->skb_mstamp_ns, from usec units to nsec units. Do not clear skb->tstamp before entering IP stacks in TX, so that qdisc or devices can implement pacing based on the earliest departure time instead of socket sk->sk_pacing_rate Packets are fed with tcp_wstamp_ns, and following patch will update tcp_wstamp_ns when both TCP and sch_fq switch to the earliest departure time mechanism. Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2018-09-12Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/netDavid S. Miller
2018-09-07tcp: really ignore MSG_ZEROCOPY if no SO_ZEROCOPYVincent Whitchurch
According to the documentation in msg_zerocopy.rst, the SO_ZEROCOPY flag was introduced because send(2) ignores unknown message flags and any legacy application which was accidentally passing the equivalent of MSG_ZEROCOPY earlier should not see any new behaviour. Before commit f214f915e7db ("tcp: enable MSG_ZEROCOPY"), a send(2) call which passed the equivalent of MSG_ZEROCOPY without setting SO_ZEROCOPY would succeed. However, after that commit, it fails with -ENOBUFS. So it appears that the SO_ZEROCOPY flag fails to fulfill its intended purpose. Fix it. Fixes: f214f915e7db ("tcp: enable MSG_ZEROCOPY") Signed-off-by: Vincent Whitchurch <vincent.whitchurch@axis.com> Acked-by: Willem de Bruijn <willemb@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2018-08-31tcp: change IPv6 flow-label upon receiving spurious retransmissionYuchung Cheng
Currently a Linux IPv6 TCP sender will change the flow label upon timeouts to potentially steer away from a data path that has gone bad. However this does not help if the problem is on the ACK path and the data path is healthy. In this case the receiver is likely to receive repeated spurious retransmission because the sender couldn't get the ACKs in time and has recurring timeouts. This patch adds another feature to mitigate this problem. It leverages the DSACK states in the receiver to change the flow label of the ACKs to speculatively re-route the ACK packets. In order to allow triggering on the second consecutive spurious RTO, the receiver changes the flow label upon sending a second consecutive DSACK for a sequence number below RCV.NXT. Signed-off-by: Yuchung Cheng <ycheng@google.com> Signed-off-by: Neal Cardwell <ncardwell@google.com> Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2018-08-03tcp: remove unneeded variable 'err'YueHaibing
variable 'err' is unmodified after initalization, so simply cleans up it and returns 0. Signed-off-by: YueHaibing <yuehaibing@huawei.com> Signed-off-by: David S. Miller <davem@davemloft.net>