1. 02 3月, 2011 1 次提交
  2. 25 2月, 2011 1 次提交
    • D
      ipv4: Rearrange how ip_route_newports() gets port keys. · dca8b089
      David S. Miller 提交于
      ip_route_newports() is the only place in the entire kernel that
      cares about the port members in the routing cache entry's lookup
      flow key.
      
      Therefore the only reason we store an entire flow inside of the
      struct rtentry is for this one special case.
      
      Rewrite ip_route_newports() such that:
      
      1) The caller passes in the original port values, so we don't need
         to use the rth->fl.fl_ip_{s,d}port values to remember them.
      
      2) The lookup flow is constructed by hand instead of being copied
         from the routing cache entry's flow.
      Signed-off-by: NDavid S. Miller <davem@davemloft.net>
      dca8b089
  3. 21 2月, 2011 1 次提交
  4. 11 2月, 2011 1 次提交
  5. 25 1月, 2011 1 次提交
    • E
      tcp: fix bug in listening_get_next() · fd0273c5
      Eric Dumazet 提交于
      commit a8b690f9 (tcp: Fix slowness in read /proc/net/tcp)
      introduced a bug in handling of SYN_RECV sockets.
      
      st->offset represents number of sockets found since beginning of
      listening_hash[st->bucket].
      
      We should not reset st->offset when iterating through
      syn_table[st->sbucket], or else if more than ~25 sockets (if
      PAGE_SIZE=4096) are in SYN_RECV state, we exit from listening_get_next()
      with a too small st->offset
      
      Next time we enter tcp_seek_last_pos(), we are not able to seek past
      already found sockets.
      Reported-by: NPK <runningdoglackey@yahoo.com>
      CC: Tom Herbert <therbert@google.com>
      Signed-off-by: NEric Dumazet <eric.dumazet@gmail.com>
      Signed-off-by: NDavid S. Miller <davem@davemloft.net>
      fd0273c5
  6. 24 12月, 2010 1 次提交
  7. 14 12月, 2010 1 次提交
    • D
      net: Abstract default ADVMSS behind an accessor. · 0dbaee3b
      David S. Miller 提交于
      Make all RTAX_ADVMSS metric accesses go through a new helper function,
      dst_metric_advmss().
      
      Leave the actual default metric as "zero" in the real metric slot,
      and compute the actual default value dynamically via a new dst_ops
      AF specific callback.
      
      For stacked IPSEC routes, we use the advmss of the path which
      preserves existing behavior.
      
      Unlike ipv4/ipv6, DecNET ties the advmss to the mtu and thus updates
      advmss on pmtu updates.  This inconsistency in advmss handling
      results in more raw metric accesses than I wish we ended up with.
      Signed-off-by: NDavid S. Miller <davem@davemloft.net>
      0dbaee3b
  8. 02 12月, 2010 1 次提交
    • D
      timewait_sock: Create and use getpeer op. · ccb7c410
      David S. Miller 提交于
      The only thing AF-specific about remembering the timestamp
      for a time-wait TCP socket is getting the peer.
      
      Abstract that behind a new timewait_sock_ops vector.
      
      Support for real IPV6 sockets is not filled in yet, but
      curiously this makes timewait recycling start to work
      for v4-mapped ipv6 sockets.
      Signed-off-by: NDavid S. Miller <davem@davemloft.net>
      ccb7c410
  9. 01 12月, 2010 3 次提交
  10. 28 11月, 2010 1 次提交
  11. 13 11月, 2010 1 次提交
  12. 21 10月, 2010 1 次提交
  13. 01 9月, 2010 1 次提交
  14. 13 7月, 2010 2 次提交
  15. 27 6月, 2010 1 次提交
  16. 17 6月, 2010 1 次提交
    • E
      inetpeer: restore small inet_peer structures · 317fe0e6
      Eric Dumazet 提交于
      Addition of rcu_head to struct inet_peer added 16bytes on 64bit arches.
      
      Thats a bit unfortunate, since old size was exactly 64 bytes.
      
      This can be solved, using an union between this rcu_head an four fields,
      that are normally used only when a refcount is taken on inet_peer.
      rcu_head is used only when refcnt=-1, right before structure freeing.
      
      Add a inet_peer_refcheck() function to check this assertion for a while.
      
      We can bring back SLAB_HWCACHE_ALIGN qualifier in kmem cache creation.
      Signed-off-by: NEric Dumazet <eric.dumazet@gmail.com>
      Signed-off-by: NDavid S. Miller <davem@davemloft.net>
      317fe0e6
  17. 11 6月, 2010 1 次提交
  18. 07 6月, 2010 1 次提交
    • T
      tcp: Fix slowness in read /proc/net/tcp · a8b690f9
      Tom Herbert 提交于
      This patch address a serious performance issue in reading the
      TCP sockets table (/proc/net/tcp).
      
      Reading the full table is done by a number of sequential read
      operations.  At each read operation, a seek is done to find the
      last socket that was previously read.  This seek operation requires
      that the sockets in the table need to be counted up to the current
      file position, and to count each of these requires taking a lock for
      each non-empty bucket.  The whole algorithm is O(n^2).
      
      The fix is to cache the last bucket value, offset within the bucket,
      and the file position returned by the last read operation.   On the
      next sequential read, the bucket and offset are used to find the
      last read socket immediately without needing ot scan the previous
      buckets  the table.  This algorithm t read the whole table is O(n).
      
      The improvement offered by this patch is easily show by performing
      cat'ing /proc/net/tcp on a machine with a lot of connections.  With
      about 182K connections in the table, I see the following:
      
      - Without patch
      time cat /proc/net/tcp > /dev/null
      
      real	1m56.729s
      user	0m0.214s
      sys	1m56.344s
      
      - With patch
      time cat /proc/net/tcp > /dev/null
      
      real	0m0.894s
      user	0m0.290s
      sys	0m0.594s
      Signed-off-by: NTom Herbert <therbert@google.com>
      Acked-by: NEric Dumazet <eric.dumazet@gmail.com>
      Signed-off-by: NDavid S. Miller <davem@davemloft.net>
      a8b690f9
  19. 05 6月, 2010 3 次提交
  20. 16 5月, 2010 1 次提交
    • E
      net: Introduce sk_route_nocaps · a465419b
      Eric Dumazet 提交于
      TCP-MD5 sessions have intermittent failures, when route cache is
      invalidated. ip_queue_xmit() has to find a new route, calls
      sk_setup_caps(sk, &rt->u.dst), destroying the 
      
      sk->sk_route_caps &= ~NETIF_F_GSO_MASK
      
      that MD5 desperately try to make all over its way (from
      tcp_transmit_skb() for example)
      
      So we send few bad packets, and everything is fine when
      tcp_transmit_skb() is called again for this socket.
      
      Since ip_queue_xmit() is at a lower level than TCP-MD5, I chose to use a
      socket field, sk_route_nocaps, containing bits to mask on sk_route_caps.
      Reported-by: NBhaskar Dutta <bhaskie@gmail.com>
      Signed-off-by: NEric Dumazet <eric.dumazet@gmail.com>
      Signed-off-by: NDavid S. Miller <davem@davemloft.net>
      a465419b
  21. 28 4月, 2010 1 次提交
  22. 21 4月, 2010 1 次提交
  23. 17 4月, 2010 1 次提交
    • T
      rfs: Receive Flow Steering · fec5e652
      Tom Herbert 提交于
      This patch implements receive flow steering (RFS).  RFS steers
      received packets for layer 3 and 4 processing to the CPU where
      the application for the corresponding flow is running.  RFS is an
      extension of Receive Packet Steering (RPS).
      
      The basic idea of RFS is that when an application calls recvmsg
      (or sendmsg) the application's running CPU is stored in a hash
      table that is indexed by the connection's rxhash which is stored in
      the socket structure.  The rxhash is passed in skb's received on
      the connection from netif_receive_skb.  For each received packet,
      the associated rxhash is used to look up the CPU in the hash table,
      if a valid CPU is set then the packet is steered to that CPU using
      the RPS mechanisms.
      
      The convolution of the simple approach is that it would potentially
      allow OOO packets.  If threads are thrashing around CPUs or multiple
      threads are trying to read from the same sockets, a quickly changing
      CPU value in the hash table could cause rampant OOO packets--
      we consider this a non-starter.
      
      To avoid OOO packets, this solution implements two types of hash
      tables: rps_sock_flow_table and rps_dev_flow_table.
      
      rps_sock_table is a global hash table.  Each entry is just a CPU
      number and it is populated in recvmsg and sendmsg as described above.
      This table contains the "desired" CPUs for flows.
      
      rps_dev_flow_table is specific to each device queue.  Each entry
      contains a CPU and a tail queue counter.  The CPU is the "current"
      CPU for a matching flow.  The tail queue counter holds the value
      of a tail queue counter for the associated CPU's backlog queue at
      the time of last enqueue for a flow matching the entry.
      
      Each backlog queue has a queue head counter which is incremented
      on dequeue, and so a queue tail counter is computed as queue head
      count + queue length.  When a packet is enqueued on a backlog queue,
      the current value of the queue tail counter is saved in the hash
      entry of the rps_dev_flow_table.
      
      And now the trick: when selecting the CPU for RPS (get_rps_cpu)
      the rps_sock_flow table and the rps_dev_flow table for the RX queue
      are consulted.  When the desired CPU for the flow (found in the
      rps_sock_flow table) does not match the current CPU (found in the
      rps_dev_flow table), the current CPU is changed to the desired CPU
      if one of the following is true:
      
      - The current CPU is unset (equal to RPS_NO_CPU)
      - Current CPU is offline
      - The current CPU's queue head counter >= queue tail counter in the
      rps_dev_flow table.  This checks if the queue tail has advanced
      beyond the last packet that was enqueued using this table entry.
      This guarantees that all packets queued using this entry have been
      dequeued, thus preserving in order delivery.
      
      Making each queue have its own rps_dev_flow table has two advantages:
      1) the tail queue counters will be written on each receive, so
      keeping the table local to interrupting CPU s good for locality.  2)
      this allows lockless access to the table-- the CPU number and queue
      tail counter need to be accessed together under mutual exclusion
      from netif_receive_skb, we assume that this is only called from
      device napi_poll which is non-reentrant.
      
      This patch implements RFS for TCP and connected UDP sockets.
      It should be usable for other flow oriented protocols.
      
      There are two configuration parameters for RFS.  The
      "rps_flow_entries" kernel init parameter sets the number of
      entries in the rps_sock_flow_table, the per rxqueue sysfs entry
      "rps_flow_cnt" contains the number of entries in the rps_dev_flow
      table for the rxqueue.  Both are rounded to power of two.
      
      The obvious benefit of RFS (over just RPS) is that it achieves
      CPU locality between the receive processing for a flow and the
      applications processing; this can result in increased performance
      (higher pps, lower latency).
      
      The benefits of RFS are dependent on cache hierarchy, application
      load, and other factors.  On simple benchmarks, we don't necessarily
      see improvement and sometimes see degradation.  However, for more
      complex benchmarks and for applications where cache pressure is
      much higher this technique seems to perform very well.
      
      Below are some benchmark results which show the potential benfit of
      this patch.  The netperf test has 500 instances of netperf TCP_RR
      test with 1 byte req. and resp.  The RPC test is an request/response
      test similar in structure to netperf RR test ith 100 threads on
      each host, but does more work in userspace that netperf.
      
      e1000e on 8 core Intel
         No RFS or RPS		104K tps at 30% CPU
         No RFS (best RPS config):    290K tps at 63% CPU
         RFS				303K tps at 61% CPU
      
      RPC test	tps	CPU%	50/90/99% usec latency	Latency StdDev
        No RFS/RPS	103K	48%	757/900/3185		4472.35
        RPS only:	174K	73%	415/993/2468		491.66
        RFS		223K	73%	379/651/1382		315.61
      Signed-off-by: NTom Herbert <therbert@google.com>
      Signed-off-by: NEric Dumazet <eric.dumazet@gmail.com>
      Signed-off-by: NDavid S. Miller <davem@davemloft.net>
      fec5e652
  24. 12 4月, 2010 2 次提交
  25. 30 3月, 2010 1 次提交
    • T
      include cleanup: Update gfp.h and slab.h includes to prepare for breaking... · 5a0e3ad6
      Tejun Heo 提交于
      include cleanup: Update gfp.h and slab.h includes to prepare for breaking implicit slab.h inclusion from percpu.h
      
      percpu.h is included by sched.h and module.h and thus ends up being
      included when building most .c files.  percpu.h includes slab.h which
      in turn includes gfp.h making everything defined by the two files
      universally available and complicating inclusion dependencies.
      
      percpu.h -> slab.h dependency is about to be removed.  Prepare for
      this change by updating users of gfp and slab facilities include those
      headers directly instead of assuming availability.  As this conversion
      needs to touch large number of source files, the following script is
      used as the basis of conversion.
      
        http://userweb.kernel.org/~tj/misc/slabh-sweep.py
      
      The script does the followings.
      
      * Scan files for gfp and slab usages and update includes such that
        only the necessary includes are there.  ie. if only gfp is used,
        gfp.h, if slab is used, slab.h.
      
      * When the script inserts a new include, it looks at the include
        blocks and try to put the new include such that its order conforms
        to its surrounding.  It's put in the include block which contains
        core kernel includes, in the same order that the rest are ordered -
        alphabetical, Christmas tree, rev-Xmas-tree or at the end if there
        doesn't seem to be any matching order.
      
      * If the script can't find a place to put a new include (mostly
        because the file doesn't have fitting include block), it prints out
        an error message indicating which .h file needs to be added to the
        file.
      
      The conversion was done in the following steps.
      
      1. The initial automatic conversion of all .c files updated slightly
         over 4000 files, deleting around 700 includes and adding ~480 gfp.h
         and ~3000 slab.h inclusions.  The script emitted errors for ~400
         files.
      
      2. Each error was manually checked.  Some didn't need the inclusion,
         some needed manual addition while adding it to implementation .h or
         embedding .c file was more appropriate for others.  This step added
         inclusions to around 150 files.
      
      3. The script was run again and the output was compared to the edits
         from #2 to make sure no file was left behind.
      
      4. Several build tests were done and a couple of problems were fixed.
         e.g. lib/decompress_*.c used malloc/free() wrappers around slab
         APIs requiring slab.h to be added manually.
      
      5. The script was run on all .h files but without automatically
         editing them as sprinkling gfp.h and slab.h inclusions around .h
         files could easily lead to inclusion dependency hell.  Most gfp.h
         inclusion directives were ignored as stuff from gfp.h was usually
         wildly available and often used in preprocessor macros.  Each
         slab.h inclusion directive was examined and added manually as
         necessary.
      
      6. percpu.h was updated not to include slab.h.
      
      7. Build test were done on the following configurations and failures
         were fixed.  CONFIG_GCOV_KERNEL was turned off for all tests (as my
         distributed build env didn't work with gcov compiles) and a few
         more options had to be turned off depending on archs to make things
         build (like ipr on powerpc/64 which failed due to missing writeq).
      
         * x86 and x86_64 UP and SMP allmodconfig and a custom test config.
         * powerpc and powerpc64 SMP allmodconfig
         * sparc and sparc64 SMP allmodconfig
         * ia64 SMP allmodconfig
         * s390 SMP allmodconfig
         * alpha SMP allmodconfig
         * um on x86_64 SMP allmodconfig
      
      8. percpu.h modifications were reverted so that it could be applied as
         a separate patch and serve as bisection point.
      
      Given the fact that I had only a couple of failures from tests on step
      6, I'm fairly confident about the coverage of this conversion patch.
      If there is a breakage, it's likely to be something in one of the arch
      headers which should be easily discoverable easily on most builds of
      the specific arch.
      Signed-off-by: NTejun Heo <tj@kernel.org>
      Guess-its-ok-by: NChristoph Lameter <cl@linux-foundation.org>
      Cc: Ingo Molnar <mingo@redhat.com>
      Cc: Lee Schermerhorn <Lee.Schermerhorn@hp.com>
      5a0e3ad6
  26. 20 3月, 2010 1 次提交
  27. 10 3月, 2010 1 次提交
  28. 09 3月, 2010 1 次提交
  29. 06 3月, 2010 2 次提交
  30. 18 1月, 2010 2 次提交
  31. 12 1月, 2010 1 次提交
  32. 16 12月, 2009 1 次提交
    • D
      tcp: Revert per-route SACK/DSACK/TIMESTAMP changes. · bb5b7c11
      David S. Miller 提交于
      It creates a regression, triggering badness for SYN_RECV
      sockets, for example:
      
      [19148.022102] Badness at net/ipv4/inet_connection_sock.c:293
      [19148.022570] NIP: c02a0914 LR: c02a0904 CTR: 00000000
      [19148.023035] REGS: eeecbd30 TRAP: 0700   Not tainted  (2.6.32)
      [19148.023496] MSR: 00029032 <EE,ME,CE,IR,DR>  CR: 24002442  XER: 00000000
      [19148.024012] TASK = eee9a820[1756] 'privoxy' THREAD: eeeca000
      
      This is likely caused by the change in the 'estab' parameter
      passed to tcp_parse_options() when invoked by the functions
      in net/ipv4/tcp_minisocks.c
      
      But even if that is fixed, the ->conn_request() changes made in
      this patch series is fundamentally wrong.  They try to use the
      listening socket's 'dst' to probe the route settings.  The
      listening socket doesn't even have a route, and you can't
      get the right route (the child request one) until much later
      after we setup all of the state, and it must be done by hand.
      
      This stuff really isn't ready, so the best thing to do is a
      full revert.  This reverts the following commits:
      
      f55017a9
      022c3f7d
      1aba721e
      cda42ebd
      345cda2f
      dc343475
      05eaade2
      6a2a2d6bSigned-off-by: NDavid S. Miller <davem@davemloft.net>
      bb5b7c11