1. 13 10月, 2015 1 次提交
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      net: SO_INCOMING_CPU setsockopt() support · 70da268b
      Eric Dumazet 提交于
      SO_INCOMING_CPU as added in commit 2c8c56e1 was a getsockopt() command
      to fetch incoming cpu handling a particular TCP flow after accept()
      
      This commits adds setsockopt() support and extends SO_REUSEPORT selection
      logic : If a TCP listener or UDP socket has this option set, a packet is
      delivered to this socket only if CPU handling the packet matches the specified
      one.
      
      This allows to build very efficient TCP servers, using one listener per
      RX queue, as the associated TCP listener should only accept flows handled
      in softirq by the same cpu.
      This provides optimal NUMA behavior and keep cpu caches hot.
      
      Note that __inet_lookup_listener() still has to iterate over the list of
      all listeners. Following patch puts sk_refcnt in a different cache line
      to let this iteration hit only shared and read mostly cache lines.
      Signed-off-by: NEric Dumazet <edumazet@google.com>
      Signed-off-by: NDavid S. Miller <davem@davemloft.net>
      70da268b
  2. 10 7月, 2015 2 次提交
  3. 28 5月, 2015 1 次提交
  4. 14 4月, 2015 1 次提交
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      tcp/dccp: get rid of central timewait timer · 789f558c
      Eric Dumazet 提交于
      Using a timer wheel for timewait sockets was nice ~15 years ago when
      memory was expensive and machines had a single processor.
      
      This does not scale, code is ugly and source of huge latencies
      (Typically 30 ms have been seen, cpus spinning on death_lock spinlock.)
      
      We can afford to use an extra 64 bytes per timewait sock and spread
      timewait load to all cpus to have better behavior.
      
      Tested:
      
      On following test, /proc/sys/net/ipv4/tcp_tw_recycle is set to 1
      on the target (lpaa24)
      
      Before patch :
      
      lpaa23:~# ./super_netperf 200 -H lpaa24 -t TCP_CC -l 60 -- -p0,0
      419594
      
      lpaa23:~# ./super_netperf 200 -H lpaa24 -t TCP_CC -l 60 -- -p0,0
      437171
      
      While test is running, we can observe 25 or even 33 ms latencies.
      
      lpaa24:~# ping -c 1000 -i 0.02 -qn lpaa23
      ...
      1000 packets transmitted, 1000 received, 0% packet loss, time 20601ms
      rtt min/avg/max/mdev = 0.020/0.217/25.771/1.535 ms, pipe 2
      
      lpaa24:~# ping -c 1000 -i 0.02 -qn lpaa23
      ...
      1000 packets transmitted, 1000 received, 0% packet loss, time 20702ms
      rtt min/avg/max/mdev = 0.019/0.183/33.761/1.441 ms, pipe 2
      
      After patch :
      
      About 90% increase of throughput :
      
      lpaa23:~# ./super_netperf 200 -H lpaa24 -t TCP_CC -l 60 -- -p0,0
      810442
      
      lpaa23:~# ./super_netperf 200 -H lpaa24 -t TCP_CC -l 60 -- -p0,0
      800992
      
      And latencies are kept to minimal values during this load, even
      if network utilization is 90% higher :
      
      lpaa24:~# ping -c 1000 -i 0.02 -qn lpaa23
      ...
      1000 packets transmitted, 1000 received, 0% packet loss, time 19991ms
      rtt min/avg/max/mdev = 0.023/0.064/0.360/0.042 ms
      Signed-off-by: NEric Dumazet <edumazet@google.com>
      Signed-off-by: NDavid S. Miller <davem@davemloft.net>
      789f558c
  5. 19 3月, 2015 4 次提交
  6. 25 8月, 2014 2 次提交
  7. 24 8月, 2014 1 次提交
  8. 20 10月, 2013 2 次提交
  9. 09 10月, 2013 2 次提交
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      ipv6: make lookups simpler and faster · efe4208f
      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>
      efe4208f
    • E
      tcp/dccp: remove twchain · 05dbc7b5
      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>
      05dbc7b5
  10. 03 10月, 2013 1 次提交
  11. 24 1月, 2013 1 次提交
    • T
      soreuseport: TCP/IPv6 implementation · 5ba24953
      Tom Herbert 提交于
      Motivation for soreuseport would be something like a web server
      binding to port 80 running with multiple threads, where each thread
      might have it's own listener socket.  This could be done as an
      alternative to other models: 1) have one listener thread which
      dispatches completed connections to workers. 2) accept on a single
      listener socket from multiple threads.  In case #1 the listener thread
      can easily become the bottleneck with high connection turn-over rate.
      In case #2, the proportion of connections accepted per thread tends
      to be uneven under high connection load (assuming simple event loop:
      while (1) { accept(); process() }, wakeup does not promote fairness
      among the sockets.  We have seen the  disproportion to be as high
      as 3:1 ratio between thread accepting most connections and the one
      accepting the fewest.  With so_reusport the distribution is
      uniform.
      Signed-off-by: NTom Herbert <therbert@google.com>
      Signed-off-by: NDavid S. Miller <davem@davemloft.net>
      5ba24953
  12. 01 12月, 2012 1 次提交
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      net: move inet_dport/inet_num in sock_common · ce43b03e
      Eric Dumazet 提交于
      commit 68835aba (net: optimize INET input path further)
      moved some fields used for tcp/udp sockets lookup in the first cache
      line of struct sock_common.
      
      This patch moves inet_dport/inet_num as well, filling a 32bit hole
      on 64 bit arches and reducing number of cache line misses in lookups.
      
      Also change INET_MATCH()/INET_TW_MATCH() to perform the ports match
      before addresses match, as this check is more discriminant.
      
      Remove the hash check from MATCH() macros because we dont need to
      re validate the hash value after taking a refcount on socket, and
      use likely/unlikely compiler hints, as the sk_hash/hash check
      makes the following conditional tests 100% predicted by cpu.
      
      Introduce skc_addrpair/skc_portpair pair values to better
      document the alignment requirements of the port/addr pairs
      used in the various MATCH() macros, and remove some casts.
      
      The namespace check can also be done at last.
      
      This slightly improves TCP/UDP lookup times.
      
      IP/TCP early demux needs inet->rx_dst_ifindex and
      TCP needs inet->min_ttl, lets group them together in same cache line.
      
      With help from Ben Hutchings & Joe Perches.
      
      Idea of this patch came after Ling Ma proposal to move skc_hash
      to the beginning of struct sock_common, and should allow him
      to submit a final version of his patch. My tests show an improvement
      doing so.
      Signed-off-by: NEric Dumazet <edumazet@google.com>
      Cc: Ben Hutchings <bhutchings@solarflare.com>
      Cc: Joe Perches <joe@perches.com>
      Cc: Ling Ma <ling.ma.program@gmail.com>
      Signed-off-by: NDavid S. Miller <davem@davemloft.net>
      ce43b03e
  13. 07 8月, 2011 1 次提交
    • D
      net: Compute protocol sequence numbers and fragment IDs using MD5. · 6e5714ea
      David S. Miller 提交于
      Computers have become a lot faster since we compromised on the
      partial MD4 hash which we use currently for performance reasons.
      
      MD5 is a much safer choice, and is inline with both RFC1948 and
      other ISS generators (OpenBSD, Solaris, etc.)
      
      Furthermore, only having 24-bits of the sequence number be truly
      unpredictable is a very serious limitation.  So the periodic
      regeneration and 8-bit counter have been removed.  We compute and
      use a full 32-bit sequence number.
      
      For ipv6, DCCP was found to use a 32-bit truncated initial sequence
      number (it needs 43-bits) and that is fixed here as well.
      Reported-by: NDan Kaminsky <dan@doxpara.com>
      Tested-by: NWilly Tarreau <w@1wt.eu>
      Signed-off-by: NDavid S. Miller <davem@davemloft.net>
      6e5714ea
  14. 19 1月, 2011 1 次提交
  15. 09 12月, 2009 1 次提交
  16. 04 12月, 2009 1 次提交
    • E
      tcp: connect() race with timewait reuse · 13475a30
      Eric Dumazet 提交于
      Its currently possible that several threads issuing a connect() find
      the same timewait socket and try to reuse it, leading to list
      corruptions.
      
      Condition for bug is that these threads bound their socket on same
      address/port of to-be-find timewait socket, and connected to same
      target. (SO_REUSEADDR needed)
      
      To fix this problem, we could unhash timewait socket while holding
      ehash lock, to make sure lookups/changes will be serialized. Only
      first thread finds the timewait socket, other ones find the
      established socket and return an EADDRNOTAVAIL error.
      
      This second version takes into account Evgeniy's review and makes sure
      inet_twsk_put() is called outside of locked sections.
      Signed-off-by: NEric Dumazet <eric.dumazet@gmail.com>
      Signed-off-by: NDavid S. Miller <davem@davemloft.net>
      13475a30
  17. 19 10月, 2009 1 次提交
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      inet: rename some inet_sock fields · c720c7e8
      Eric Dumazet 提交于
      In order to have better cache layouts of struct sock (separate zones
      for rx/tx paths), we need this preliminary patch.
      
      Goal is to transfert fields used at lookup time in the first
      read-mostly cache line (inside struct sock_common) and move sk_refcnt
      to a separate cache line (only written by rx path)
      
      This patch adds inet_ prefix to daddr, rcv_saddr, dport, num, saddr,
      sport and id fields. This allows a future patch to define these
      fields as macros, like sk_refcnt, without name clashes.
      Signed-off-by: NEric Dumazet <eric.dumazet@gmail.com>
      Signed-off-by: NDavid S. Miller <davem@davemloft.net>
      c720c7e8
  18. 13 10月, 2009 1 次提交
  19. 26 2月, 2009 1 次提交
  20. 24 11月, 2008 1 次提交
    • E
      net: Convert TCP/DCCP listening hash tables to use RCU · c25eb3bf
      Eric Dumazet 提交于
      This is the last step to be able to perform full RCU lookups
      in __inet_lookup() : After established/timewait tables, we
      add RCU lookups to listening hash table.
      
      The only trick here is that a socket of a given type (TCP ipv4,
      TCP ipv6, ...) can now flight between two different tables
      (established and listening) during a RCU grace period, so we
      must use different 'nulls' end-of-chain values for two tables.
      
      We define a large value :
      
      #define LISTENING_NULLS_BASE (1U << 29)
      
      So that slots in listening table are guaranteed to have different
      end-of-chain values than slots in established table. A reader can
      still detect it finished its lookup in the right chain.
      Signed-off-by: NEric Dumazet <dada1@cosmosbay.com>
      Signed-off-by: NDavid S. Miller <davem@davemloft.net>
      c25eb3bf
  21. 21 11月, 2008 1 次提交
  22. 20 11月, 2008 1 次提交
  23. 17 11月, 2008 1 次提交
    • E
      net: Convert TCP & DCCP hash tables to use RCU / hlist_nulls · 3ab5aee7
      Eric Dumazet 提交于
      RCU was added to UDP lookups, using a fast infrastructure :
      - sockets kmem_cache use SLAB_DESTROY_BY_RCU and dont pay the
        price of call_rcu() at freeing time.
      - hlist_nulls permits to use few memory barriers.
      
      This patch uses same infrastructure for TCP/DCCP established
      and timewait sockets.
      
      Thanks to SLAB_DESTROY_BY_RCU, no slowdown for applications
      using short lived TCP connections. A followup patch, converting
      rwlocks to spinlocks will even speedup this case.
      
      __inet_lookup_established() is pretty fast now we dont have to
      dirty a contended cache line (read_lock/read_unlock)
      
      Only established and timewait hashtable are converted to RCU
      (bind table and listen table are still using traditional locking)
      Signed-off-by: NEric Dumazet <dada1@cosmosbay.com>
      Signed-off-by: NDavid S. Miller <davem@davemloft.net>
      3ab5aee7
  24. 26 7月, 2008 1 次提交
  25. 17 7月, 2008 1 次提交
  26. 17 6月, 2008 2 次提交
  27. 01 4月, 2008 1 次提交
  28. 26 3月, 2008 2 次提交
  29. 23 3月, 2008 1 次提交
    • P
      [SOCK]: Add udp_hash member to struct proto. · 39d8cda7
      Pavel Emelyanov 提交于
      Inspired by the commit ab1e0a13 ([SOCK] proto: Add hashinfo member to 
      struct proto) from Arnaldo, I made similar thing for UDP/-Lite IPv4 
      and -v6 protocols.
      
      The result is not that exciting, but it removes some levels of
      indirection in udpxxx_get_port and saves some space in code and text.
      
      The first step is to union existing hashinfo and new udp_hash on the
      struct proto and give a name to this union, since future initialization 
      of tcpxxx_prot, dccp_vx_protinfo and udpxxx_protinfo will cause gcc 
      warning about inability to initialize anonymous member this way.
      Signed-off-by: NPavel Emelyanov <xemul@openvz.org>
      Signed-off-by: NDavid S. Miller <davem@davemloft.net>
      39d8cda7
  30. 05 2月, 2008 1 次提交
  31. 03 2月, 2008 1 次提交
    • A
      [SOCK] proto: Add hashinfo member to struct proto · ab1e0a13
      Arnaldo Carvalho de Melo 提交于
      This way we can remove TCP and DCCP specific versions of
      
      sk->sk_prot->get_port: both v4 and v6 use inet_csk_get_port
      sk->sk_prot->hash:     inet_hash is directly used, only v6 need
                             a specific version to deal with mapped sockets
      sk->sk_prot->unhash:   both v4 and v6 use inet_hash directly
      
      struct inet_connection_sock_af_ops also gets a new member, bind_conflict, so
      that inet_csk_get_port can find the per family routine.
      
      Now only the lookup routines receive as a parameter a struct inet_hashtable.
      
      With this we further reuse code, reducing the difference among INET transport
      protocols.
      
      Eventually work has to be done on UDP and SCTP to make them share this
      infrastructure and get as a bonus inet_diag interfaces so that iproute can be
      used with these protocols.
      
      net-2.6/net/ipv4/inet_hashtables.c:
        struct proto			     |   +8
        struct inet_connection_sock_af_ops |   +8
       2 structs changed
        __inet_hash_nolisten               |  +18
        __inet_hash                        | -210
        inet_put_port                      |   +8
        inet_bind_bucket_create            |   +1
        __inet_hash_connect                |   -8
       5 functions changed, 27 bytes added, 218 bytes removed, diff: -191
      
      net-2.6/net/core/sock.c:
        proto_seq_show                     |   +3
       1 function changed, 3 bytes added, diff: +3
      
      net-2.6/net/ipv4/inet_connection_sock.c:
        inet_csk_get_port                  |  +15
       1 function changed, 15 bytes added, diff: +15
      
      net-2.6/net/ipv4/tcp.c:
        tcp_set_state                      |   -7
       1 function changed, 7 bytes removed, diff: -7
      
      net-2.6/net/ipv4/tcp_ipv4.c:
        tcp_v4_get_port                    |  -31
        tcp_v4_hash                        |  -48
        tcp_v4_destroy_sock                |   -7
        tcp_v4_syn_recv_sock               |   -2
        tcp_unhash                         | -179
       5 functions changed, 267 bytes removed, diff: -267
      
      net-2.6/net/ipv6/inet6_hashtables.c:
        __inet6_hash |   +8
       1 function changed, 8 bytes added, diff: +8
      
      net-2.6/net/ipv4/inet_hashtables.c:
        inet_unhash                        | +190
        inet_hash                          | +242
       2 functions changed, 432 bytes added, diff: +432
      
      vmlinux:
       16 functions changed, 485 bytes added, 492 bytes removed, diff: -7
      
      /home/acme/git/net-2.6/net/ipv6/tcp_ipv6.c:
        tcp_v6_get_port                    |  -31
        tcp_v6_hash                        |   -7
        tcp_v6_syn_recv_sock               |   -9
       3 functions changed, 47 bytes removed, diff: -47
      
      /home/acme/git/net-2.6/net/dccp/proto.c:
        dccp_destroy_sock                  |   -7
        dccp_unhash                        | -179
        dccp_hash                          |  -49
        dccp_set_state                     |   -7
        dccp_done                          |   +1
       5 functions changed, 1 bytes added, 242 bytes removed, diff: -241
      
      /home/acme/git/net-2.6/net/dccp/ipv4.c:
        dccp_v4_get_port                   |  -31
        dccp_v4_request_recv_sock          |   -2
       2 functions changed, 33 bytes removed, diff: -33
      
      /home/acme/git/net-2.6/net/dccp/ipv6.c:
        dccp_v6_get_port                   |  -31
        dccp_v6_hash                       |   -7
        dccp_v6_request_recv_sock          |   +5
       3 functions changed, 5 bytes added, 38 bytes removed, diff: -33
      Signed-off-by: NArnaldo Carvalho de Melo <acme@redhat.com>
      Signed-off-by: NDavid S. Miller <davem@davemloft.net>
      ab1e0a13