- 28 6月, 2014 9 次提交
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由 Octavian Purdila 提交于
Signed-off-by: NOctavian Purdila <octavian.purdila@intel.com> Signed-off-by: NDavid S. Miller <davem@davemloft.net>
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由 Octavian Purdila 提交于
Create a new tcp_request_sock_ops method to unify the IPv4/IPv6 signature for tcp_v[46]_send_synack. This allows us to later unify tcp_v4_rtx_synack with tcp_v6_rtx_synack and tcp_v4_conn_request with tcp_v4_conn_request. Signed-off-by: NOctavian Purdila <octavian.purdila@intel.com> Signed-off-by: NDavid S. Miller <davem@davemloft.net>
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由 Octavian Purdila 提交于
More work in preparation of unifying tcp_v4_conn_request and tcp_v6_conn_request: indirect the init sequence calls via the tcp_request_sock_ops. Signed-off-by: NOctavian Purdila <octavian.purdila@intel.com> Signed-off-by: NDavid S. Miller <davem@davemloft.net>
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由 Octavian Purdila 提交于
Make the tcp_v6_conn_request calls flow similar with that of tcp_v4_conn_request. Note that want_cookie can be true only if isn is zero and that is why we can move the if (want_cookie) block out of the if (!isn) block. Moving security_inet_conn_request() has a couple of side effects: missing inet_rsk(req)->ecn_ok update and the req->cookie_ts update. However, neither SELinux nor Smack security hooks seems to check them. This change should also avoid future different behaviour for IPv4 and IPv6 in the security hooks. Signed-off-by: NOctavian Purdila <octavian.purdila@intel.com> Acked-by: NPaul Moore <paul@paul-moore.com> Signed-off-by: NDavid S. Miller <davem@davemloft.net>
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由 Octavian Purdila 提交于
Create wrappers with same signature for the IPv4/IPv6 request routing calls and use these wrappers (via route_req method from tcp_request_sock_ops) in tcp_v4_conn_request and tcp_v6_conn_request with the purpose of unifying the two functions in a later patch. We can later drop the wrapper functions and modify inet_csk_route_req and inet6_cks_route_req to use the same signature. Signed-off-by: NOctavian Purdila <octavian.purdila@intel.com> Signed-off-by: NDavid S. Miller <davem@davemloft.net>
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由 Octavian Purdila 提交于
Move the specific IPv4/IPv6 cookie sequence initialization to a new method in tcp_request_sock_ops in preparation for unifying tcp_v4_conn_request and tcp_v6_conn_request. Signed-off-by: NOctavian Purdila <octavian.purdila@intel.com> Signed-off-by: NDavid S. Miller <davem@davemloft.net>
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由 Octavian Purdila 提交于
Move the specific IPv4/IPv6 intializations to a new method in tcp_request_sock_ops in preparation for unifying tcp_v4_conn_request and tcp_v6_conn_request. Signed-off-by: NOctavian Purdila <octavian.purdila@intel.com> Signed-off-by: NDavid S. Miller <davem@davemloft.net>
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由 Octavian Purdila 提交于
Since pktops is only used for IPv6 only and opts is used for IPv4 only, we can move these fields into a union and this allows us to drop the inet6_reqsk_alloc function as after this change it becomes equivalent with inet_reqsk_alloc. This patch also fixes a kmemcheck issue in the IPv6 stack: the flags field was not annotated after a request_sock was allocated. Signed-off-by: NOctavian Purdila <octavian.purdila@intel.com> Signed-off-by: NDavid S. Miller <davem@davemloft.net>
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由 Octavian Purdila 提交于
Commit 016818d0 (tcp: TCP Fast Open Server - take SYNACK RTT after completing 3WHS) changes the code to only take a snt_synack timestamp when a SYNACK transmit or retransmit succeeds. This behaviour is later broken by commit 843f4a55 (tcp: use tcp_v4_send_synack on first SYN-ACK), as snt_synack is now updated even if tcp_v4_send_synack fails. Also, commit 3a19ce0e (tcp: IPv6 support for fastopen server) misses the required IPv6 updates for 016818d0. This patch makes sure that snt_synack is updated only when the SYNACK trasnmit/retransmit succeeds, for both IPv4 and IPv6. Cc: Cardwell <ncardwell@google.com> Cc: Daniel Lee <longinus00@gmail.com> Cc: Yuchung Cheng <ycheng@google.com> Signed-off-by: NOctavian Purdila <octavian.purdila@intel.com> Signed-off-by: NDavid S. Miller <davem@davemloft.net>
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- 18 6月, 2014 1 次提交
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由 Octavian Purdila 提交于
ir_mark initialization is done for both TCP v4 and v6, move it in the common tcp_openreq_init function. Signed-off-by: NOctavian Purdila <octavian.purdila@intel.com> Signed-off-by: NDavid S. Miller <davem@davemloft.net>
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- 24 5月, 2014 1 次提交
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由 Tom Herbert 提交于
It doesn't seem like an protocols are setting anything other than the default, and allowing to arbitrarily disable checksums for a whole protocol seems dangerous. This can be done on a per socket basis. Signed-off-by: NTom Herbert <therbert@google.com> Signed-off-by: NDavid S. Miller <davem@davemloft.net>
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- 14 5月, 2014 4 次提交
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由 Lorenzo Colitti 提交于
When using mark-based routing, sockets returned from accept() may need to be marked differently depending on the incoming connection request. This is the case, for example, if different socket marks identify different networks: a listening socket may want to accept connections from all networks, but each connection should be marked with the network that the request came in on, so that subsequent packets are sent on the correct network. This patch adds a sysctl to mark TCP sockets based on the fwmark of the incoming SYN packet. If enabled, and an unmarked socket receives a SYN, then the SYN packet's fwmark is written to the connection's inet_request_sock, and later written back to the accepted socket when the connection is established. If the socket already has a nonzero mark, then the behaviour is the same as it is today, i.e., the listening socket's fwmark is used. Black-box tested using user-mode linux: - IPv4/IPv6 SYN+ACK, FIN, etc. packets are routed based on the mark of the incoming SYN packet. - The socket returned by accept() is marked with the mark of the incoming SYN packet. - Tested with syncookies=1 and syncookies=2. Signed-off-by: NLorenzo Colitti <lorenzo@google.com> Signed-off-by: NDavid S. Miller <davem@davemloft.net>
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由 Lorenzo Colitti 提交于
Kernel-originated IP packets that have no user socket associated with them (e.g., ICMP errors and echo replies, TCP RSTs, etc.) are emitted with a mark of zero. Add a sysctl to make them have the same mark as the packet they are replying to. This allows an administrator that wishes to do so to use mark-based routing, firewalling, etc. for these replies by marking the original packets inbound. Tested using user-mode linux: - ICMP/ICMPv6 echo replies and errors. - TCP RST packets (IPv4 and IPv6). Signed-off-by: NLorenzo Colitti <lorenzo@google.com> Signed-off-by: NDavid S. Miller <davem@davemloft.net>
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由 Daniel Lee 提交于
After all the preparatory works, supporting IPv6 in Fast Open is now easy. We pretty much just mirror v4 code. The only difference is how we generate the Fast Open cookie for IPv6 sockets. Since Fast Open cookie is 128 bits and we use AES 128, we use CBC-MAC to encrypt both the source and destination IPv6 addresses since the cookie is a MAC tag. Signed-off-by: NDaniel Lee <longinus00@gmail.com> Signed-off-by: NYuchung Cheng <ycheng@google.com> Signed-off-by: NJerry Chu <hkchu@google.com> Acked-by: NNeal Cardwell <ncardwell@google.com> Signed-off-by: NDavid S. Miller <davem@davemloft.net>
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由 Yuchung Cheng 提交于
If a fast open socket is already accepted by the user, it should be treated like a connected socket to record the ICMP error in sk_softerr, so the user can fetch it. Do that in both tcp_v4_err and tcp_v6_err. Also refactor the sequence window check to improve readability (e.g., there were two local variables named 'req'). Signed-off-by: NYuchung Cheng <ycheng@google.com> Signed-off-by: NDaniel Lee <longinus00@gmail.com> Signed-off-by: NJerry Chu <hkchu@google.com> Acked-by: NNeal Cardwell <ncardwell@google.com> Signed-off-by: NDavid S. Miller <davem@davemloft.net>
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- 06 5月, 2014 1 次提交
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由 Tom Herbert 提交于
Call skb_checksum_init instead of private functions. Signed-off-by: NTom Herbert <therbert@google.com> Signed-off-by: NDavid S. Miller <davem@davemloft.net>
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- 12 4月, 2014 1 次提交
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由 Lorenzo Colitti 提交于
net-next commit 9c76a114, ipv6: tcp_ipv6 policy route issue, had a boolean logic error that caused incorrect behaviour for TCP SYN+ACK when oif-based rules are in use. Specifically: 1. If a SYN comes in from a global address, and sk_bound_dev_if is not set, the routing lookup has oif set to the interface the SYN came in on. Instead, it should have oif unset, because for global addresses, the incoming interface doesn't necessarily have any bearing on the interface the SYN+ACK is sent out on. 2. If a SYN comes in from a link-local address, and sk_bound_dev_if is set, the routing lookup has oif set to the interface the SYN came in on. Instead, it should have oif set to sk_bound_dev_if, because that's what the application requested. Signed-off-by: NLorenzo Colitti <lorenzo@google.com> Acked-by: NHannes Frederic Sowa <hannes@stressinduktion.org> Signed-off-by: NDavid S. Miller <davem@davemloft.net>
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- 01 4月, 2014 2 次提交
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由 Wang Yufen 提交于
The issue raises when adding policy route, specify a particular NIC as oif, the policy route did not take effect. The reason is that fl6.oif is not set and route map failed. From the tcp_v6_send_response function, if the binding address is linklocal, fl6.oif is set, but not for global address. Acked-by: NHannes Frederic Sowa <hannes@stressinduktion.org> Signed-off-by: NWang Yufen <wangyufen@huawei.com> Signed-off-by: NDavid S. Miller <davem@davemloft.net>
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由 Wang Yufen 提交于
Signed-off-by: NWang Yufen <wangyufen@huawei.com> Signed-off-by: NDavid S. Miller <davem@davemloft.net>
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- 04 3月, 2014 1 次提交
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由 Yuchung Cheng 提交于
Add the following snmp stats: TCPFastOpenActiveFail: Fast Open attempts (SYN/data) failed beacuse the remote does not accept it or the attempts timed out. TCPSynRetrans: number of SYN and SYN/ACK retransmits to break down retransmissions into SYN, fast-retransmits, timeout retransmits, etc. TCPOrigDataSent: number of outgoing packets with original data (excluding retransmission but including data-in-SYN). This counter is different from TcpOutSegs because TcpOutSegs also tracks pure ACKs. TCPOrigDataSent is more useful to track the TCP retransmission rate. Change TCPFastOpenActive to track only successful Fast Opens to be symmetric to TCPFastOpenPassive. Signed-off-by: NYuchung Cheng <ycheng@google.com> Signed-off-by: NEric Dumazet <edumazet@google.com> Signed-off-by: NNandita Dukkipati <nanditad@google.com> Signed-off-by: NLawrence Brakmo <brakmo@google.com> Signed-off-by: NDavid S. Miller <davem@davemloft.net>
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- 22 1月, 2014 1 次提交
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由 Peter Pan(潘卫平) 提交于
As tcp_rcv_state_process() has already calls tcp_mtup_init() for non-fastopen sock, we can delete the redundant calls of tcp_mtup_init() in tcp_{v4,v6}_syn_recv_sock(). Signed-off-by: NWeiping Pan <panweiping3@gmail.com> Signed-off-by: NDavid S. Miller <davem@davemloft.net>
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- 20 1月, 2014 1 次提交
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由 Florent Fourcot 提交于
With this option, the socket will reply with the flow label value read on received packets. The goal is to have a connection with the same flow label in both direction of the communication. Changelog of V4: * Do not erase the flow label on the listening socket. Use pktopts to store the received value Signed-off-by: NFlorent Fourcot <florent.fourcot@enst-bretagne.fr> Acked-by: NHannes Frederic Sowa <hannes@stressinduktion.org> Signed-off-by: NDavid S. Miller <davem@davemloft.net>
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- 18 1月, 2014 1 次提交
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由 Florent Fourcot 提交于
This patch is following the commit b903d324 (ipv6: tcp: fix TCLASS value in ACK messages sent from TIME_WAIT). For the same reason than tclass, we have to store the flow label in the inet_timewait_sock to provide consistency of flow label on the last ACK. Signed-off-by: NFlorent Fourcot <florent.fourcot@enst-bretagne.fr> Signed-off-by: NDavid S. Miller <davem@davemloft.net>
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- 27 12月, 2013 1 次提交
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由 Weilong Chen 提交于
Fix some checkpatch errors for tcp_ipv6.c Signed-off-by: NWeilong Chen <chenweilong@huawei.com> Signed-off-by: NDavid S. Miller <davem@davemloft.net>
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- 19 12月, 2013 1 次提交
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由 Hannes Frederic Sowa 提交于
IPV6_PMTU_INTERFACE is the same as IPV6_PMTU_PROBE for ipv6. Add it nontheless for symmetry with IPv4 sockets. Also drop incoming MTU information if this mode is enabled. The additional bit in ipv6_pinfo just eats in the padding behind the bitfield. There are no changes to the layout of the struct at all. Signed-off-by: NHannes Frederic Sowa <hannes@stressinduktion.org> Signed-off-by: NDavid S. Miller <davem@davemloft.net>
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- 11 12月, 2013 1 次提交
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由 Florent Fourcot 提交于
This patch is following b579035f "ipv6: remove old conditions on flow label sharing" Since there is no reason to restrict a label to a destination, we should not erase the destination value of a socket with the value contained in the flow label storage. This patch allows to really have the same flow label to more than one destination. Signed-off-by: NFlorent Fourcot <florent.fourcot@enst-bretagne.fr> Reviewed-by: NHannes Frederic Sowa <hannes@stressinduktion.org> Signed-off-by: NDavid S. Miller <davem@davemloft.net>
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- 10 12月, 2013 2 次提交
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由 Florent Fourcot 提交于
tclass information in now already stored in rcv_flowinfo We do not need to store the same information twice. Signed-off-by: NFlorent Fourcot <florent.fourcot@enst-bretagne.fr> Reviewed-by: NHannes Frederic Sowa <hannes@stressinduktion.org> Signed-off-by: NDavid S. Miller <davem@davemloft.net>
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由 Florent Fourcot 提交于
The current implementation of IPV6_FLOWINFO only gives a result if pktoptions is available (thanks to the ip6_datagram_recv_ctl function). It gives inconsistent results to user space, sometimes there is a result for getsockopt(IPV6_FLOWINFO), sometimes not. This patch add rcv_flowinfo to store it, and return it to the userspace in the same way than other pkt_options. Signed-off-by: NFlorent Fourcot <florent.fourcot@enst-bretagne.fr> Reviewed-by: NHannes Frederic Sowa <hannes@stressinduktion.org> Signed-off-by: NDavid S. Miller <davem@davemloft.net>
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- 06 12月, 2013 1 次提交
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由 Steffen Klassert 提交于
FLOWI_FLAG_CAN_SLEEP was used to notify xfrm about the posibility to sleep until the needed states are resolved. This code is gone, so FLOWI_FLAG_CAN_SLEEP is not needed anymore. Signed-off-by: NSteffen Klassert <steffen.klassert@secunet.com>
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- 22 10月, 2013 1 次提交
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由 Eric W. Biederman 提交于
The code that is implemented is per memory cgroup not per netns, and having per netns bits is just confusing. Remove the per netns bits to make it easier to see what is really going on. Signed-off-by: N"Eric W. Biederman" <ebiederm@xmission.com> Signed-off-by: NDavid S. Miller <davem@davemloft.net>
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- 11 10月, 2013 1 次提交
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由 Eric Dumazet 提交于
In commit 634fb979 ("inet: includes a sock_common in request_sock") I forgot that the two ports in sock_common do not have same byte order : skc_dport is __be16 (network order), but skc_num is __u16 (host order) So sparse complains because ir_loc_port (mapped into skc_num) is considered as __u16 while it should be __be16 Let rename ir_loc_port to ireq->ir_num (analogy with inet->inet_num), and perform appropriate htons/ntohs conversions. Signed-off-by: NEric Dumazet <edumazet@google.com> Reported-by: NWu Fengguang <fengguang.wu@intel.com> Signed-off-by: NDavid S. Miller <davem@davemloft.net>
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- 10 10月, 2013 1 次提交
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由 Eric Dumazet 提交于
TCP listener refactoring, part 5 : We want to be able to insert request sockets (SYN_RECV) into main ehash table instead of the per listener hash table to allow RCU lookups and remove listener lock contention. This patch includes the needed struct sock_common in front of struct request_sock This means there is no more inet6_request_sock IPv6 specific structure. Following inet_request_sock fields were renamed as they became macros to reference fields from struct sock_common. Prefix ir_ was chosen to avoid name collisions. loc_port -> ir_loc_port loc_addr -> ir_loc_addr rmt_addr -> ir_rmt_addr rmt_port -> ir_rmt_port iif -> ir_iif Signed-off-by: NEric Dumazet <edumazet@google.com> Signed-off-by: NDavid S. Miller <davem@davemloft.net>
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- 09 10月, 2013 2 次提交
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由 Eric Dumazet 提交于
TCP listener refactoring, part 4 : To speed up inet lookups, we moved IPv4 addresses from inet to struct sock_common Now is time to do the same for IPv6, because it permits us to have fast lookups for all kind of sockets, including upcoming SYN_RECV. Getting IPv6 addresses in TCP lookups currently requires two extra cache lines, plus a dereference (and memory stall). inet6_sk(sk) does the dereference of inet_sk(__sk)->pinet6 This patch is way bigger than its IPv4 counter part, because for IPv4, we could add aliases (inet_daddr, inet_rcv_saddr), while on IPv6, it's not doable easily. inet6_sk(sk)->daddr becomes sk->sk_v6_daddr inet6_sk(sk)->rcv_saddr becomes sk->sk_v6_rcv_saddr And timewait socket also have tw->tw_v6_daddr & tw->tw_v6_rcv_saddr at the same offset. We get rid of INET6_TW_MATCH() as INET6_MATCH() is now the generic macro. Signed-off-by: NEric Dumazet <edumazet@google.com> Signed-off-by: NDavid S. Miller <davem@davemloft.net>
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由 Eric Dumazet 提交于
TCP listener refactoring, part 3 : Our goal is to hash SYN_RECV sockets into main ehash for fast lookup, and parallel SYN processing. Current inet_ehash_bucket contains two chains, one for ESTABLISH (and friend states) sockets, another for TIME_WAIT sockets only. As the hash table is sized to get at most one socket per bucket, it makes little sense to have separate twchain, as it makes the lookup slightly more complicated, and doubles hash table memory usage. If we make sure all socket types have the lookup keys at the same offsets, we can use a generic and faster lookup. It turns out TIME_WAIT and ESTABLISHED sockets already have common lookup fields for IPv4. [ INET_TW_MATCH() is no longer needed ] I'll provide a follow-up to factorize IPv6 lookup as well, to remove INET6_TW_MATCH() This way, SYN_RECV pseudo sockets will be supported the same. A new sock_gen_put() helper is added, doing either a sock_put() or inet_twsk_put() [ and will support SYN_RECV later ]. Note this helper should only be called in real slow path, when rcu lookup found a socket that was moved to another identity (freed/reused immediately), but could eventually be used in other contexts, like sock_edemux() Before patch : dmesg | grep "TCP established" TCP established hash table entries: 524288 (order: 11, 8388608 bytes) After patch : TCP established hash table entries: 524288 (order: 10, 4194304 bytes) Signed-off-by: NEric Dumazet <edumazet@google.com> Signed-off-by: NDavid S. Miller <davem@davemloft.net>
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- 04 10月, 2013 1 次提交
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由 Eric Dumazet 提交于
While working on tcp listener refactoring, I found that it would really make things easier if sock_common could include the IPv6 addresses needed in the lookups, instead of doing very complex games to get their values (depending on sock being SYN_RECV, ESTABLISHED, TIME_WAIT) For this to happen, I need to be sure that tcp6_timewait_sock and tcp_timewait_sock consume same number of cache lines. This is possible if we only use 32bits for tw_ttd, as we remove one 32bit hole in inet_timewait_sock inet_tw_time_stamp() is defined and used, even if its current implementation looks like tcp_time_stamp : We might need finer resolution for tcp_time_stamp in the future. Before patch : sizeof(struct tcp6_timewait_sock) = 0xc8 After patch : sizeof(struct tcp6_timewait_sock) = 0xc0 Signed-off-by: NEric Dumazet <edumazet@google.com> Signed-off-by: NDavid S. Miller <davem@davemloft.net>
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- 05 9月, 2013 1 次提交
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由 Daniel Borkmann 提交于
In tcp_v6_do_rcv() code, when processing pkt options, we soley work on our skb clone opt_skb that we've created earlier before entering tcp_rcv_established() on our way. However, only in condition ... if (np->rxopt.bits.rxtclass) np->rcv_tclass = ipv6_get_dsfield(ipv6_hdr(skb)); ... we work on skb itself. As we extract every other information out of opt_skb in ipv6_pktoptions path, this seems wrong, since skb can already be released by tcp_rcv_established() earlier on. When we try to access it in ipv6_hdr(), we will dereference freed skb. [ Bug added by commit 4c507d28 ("net: implement IP_RECVTOS for IP_PKTOPTIONS") ] Signed-off-by: NDaniel Borkmann <dborkman@redhat.com> Cc: Eric Dumazet <eric.dumazet@gmail.com> Acked-by: NEric Dumazet <edumazet@google.com> Acked-by: NJiri Benc <jbenc@redhat.com> Signed-off-by: NDavid S. Miller <davem@davemloft.net>
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- 04 9月, 2013 1 次提交
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由 Vijay Subramanian 提交于
tcp_rcv_established() returns only one value namely 0. We change the return value to void (as suggested by David Miller). After commit 0c24604b (tcp: implement RFC 5961 4.2), we no longer send RSTs in response to SYNs. We can remove the check and processing on the return value of tcp_rcv_established(). We also fix jtcp_rcv_established() in tcp_probe.c to match that of tcp_rcv_established(). Signed-off-by: NVijay Subramanian <subramanian.vijay@gmail.com> Signed-off-by: NDavid S. Miller <davem@davemloft.net>
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- 16 8月, 2013 1 次提交
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由 Francesco Fusco 提交于
UIDs are printed in the proc_fs as signed int, whereas they are unsigned int. Signed-off-by: NFrancesco Fusco <ffusco@redhat.com> Signed-off-by: NDavid S. Miller <davem@davemloft.net>
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- 31 7月, 2013 1 次提交
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由 Hannes Frederic Sowa 提交于
| If you want to test which effects syncookies have to your | network connections you can set this knob to 2 to enable | unconditionally generation of syncookies. Original idea and first implementation by Eric Dumazet. Cc: Florian Westphal <fw@strlen.de> Cc: David Miller <davem@davemloft.net> Signed-off-by: NEric Dumazet <eric.dumazet@gmail.com> Signed-off-by: NHannes Frederic Sowa <hannes@stressinduktion.org> Signed-off-by: NDavid S. Miller <davem@davemloft.net>
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- 25 7月, 2013 1 次提交
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由 Eric Dumazet 提交于
Idea of this patch is to add optional limitation of number of unsent bytes in TCP sockets, to reduce usage of kernel memory. TCP receiver might announce a big window, and TCP sender autotuning might allow a large amount of bytes in write queue, but this has little performance impact if a large part of this buffering is wasted : Write queue needs to be large only to deal with large BDP, not necessarily to cope with scheduling delays (incoming ACKS make room for the application to queue more bytes) For most workloads, using a value of 128 KB or less is OK to give applications enough time to react to POLLOUT events in time (or being awaken in a blocking sendmsg()) This patch adds two ways to set the limit : 1) Per socket option TCP_NOTSENT_LOWAT 2) A sysctl (/proc/sys/net/ipv4/tcp_notsent_lowat) for sockets not using TCP_NOTSENT_LOWAT socket option (or setting a zero value) Default value being UINT_MAX (0xFFFFFFFF), meaning this has no effect. This changes poll()/select()/epoll() to report POLLOUT only if number of unsent bytes is below tp->nosent_lowat Note this might increase number of sendmsg()/sendfile() calls when using non blocking sockets, and increase number of context switches for blocking sockets. Note this is not related to SO_SNDLOWAT (as SO_SNDLOWAT is defined as : Specify the minimum number of bytes in the buffer until the socket layer will pass the data to the protocol) Tested: netperf sessions, and watching /proc/net/protocols "memory" column for TCP With 200 concurrent netperf -t TCP_STREAM sessions, amount of kernel memory used by TCP buffers shrinks by ~55 % (20567 pages instead of 45458) lpq83:~# echo -1 >/proc/sys/net/ipv4/tcp_notsent_lowat lpq83:~# (super_netperf 200 -t TCP_STREAM -H remote -l 90 &); sleep 60 ; grep TCP /proc/net/protocols TCPv6 1880 2 45458 no 208 yes ipv6 y y y y y y y y y y y y y n y y y y y TCP 1696 508 45458 no 208 yes kernel y y y y y y y y y y y y y n y y y y y lpq83:~# echo 131072 >/proc/sys/net/ipv4/tcp_notsent_lowat lpq83:~# (super_netperf 200 -t TCP_STREAM -H remote -l 90 &); sleep 60 ; grep TCP /proc/net/protocols TCPv6 1880 2 20567 no 208 yes ipv6 y y y y y y y y y y y y y n y y y y y TCP 1696 508 20567 no 208 yes kernel y y y y y y y y y y y y y n y y y y y Using 128KB has no bad effect on the throughput or cpu usage of a single flow, although there is an increase of context switches. A bonus is that we hold socket lock for a shorter amount of time and should improve latencies of ACK processing. lpq83:~# echo -1 >/proc/sys/net/ipv4/tcp_notsent_lowat lpq83:~# perf stat -e context-switches ./netperf -H 7.7.7.84 -t omni -l 20 -c -i10,3 OMNI Send TEST from 0.0.0.0 (0.0.0.0) port 0 AF_INET to 7.7.7.84 () port 0 AF_INET : +/-2.500% @ 99% conf. Local Remote Local Elapsed Throughput Throughput Local Local Remote Remote Local Remote Service Send Socket Recv Socket Send Time Units CPU CPU CPU CPU Service Service Demand Size Size Size (sec) Util Util Util Util Demand Demand Units Final Final % Method % Method 1651584 6291456 16384 20.00 17447.90 10^6bits/s 3.13 S -1.00 U 0.353 -1.000 usec/KB Performance counter stats for './netperf -H 7.7.7.84 -t omni -l 20 -c -i10,3': 412,514 context-switches 200.034645535 seconds time elapsed lpq83:~# echo 131072 >/proc/sys/net/ipv4/tcp_notsent_lowat lpq83:~# perf stat -e context-switches ./netperf -H 7.7.7.84 -t omni -l 20 -c -i10,3 OMNI Send TEST from 0.0.0.0 (0.0.0.0) port 0 AF_INET to 7.7.7.84 () port 0 AF_INET : +/-2.500% @ 99% conf. Local Remote Local Elapsed Throughput Throughput Local Local Remote Remote Local Remote Service Send Socket Recv Socket Send Time Units CPU CPU CPU CPU Service Service Demand Size Size Size (sec) Util Util Util Util Demand Demand Units Final Final % Method % Method 1593240 6291456 16384 20.00 17321.16 10^6bits/s 3.35 S -1.00 U 0.381 -1.000 usec/KB Performance counter stats for './netperf -H 7.7.7.84 -t omni -l 20 -c -i10,3': 2,675,818 context-switches 200.029651391 seconds time elapsed Signed-off-by: NEric Dumazet <edumazet@google.com> Cc: Neal Cardwell <ncardwell@google.com> Cc: Yuchung Cheng <ycheng@google.com> Acked-By: NYuchung Cheng <ycheng@google.com> Signed-off-by: NDavid S. Miller <davem@davemloft.net>
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