1. 28 3月, 2013 1 次提交
  2. 27 3月, 2013 1 次提交
  3. 28 2月, 2013 1 次提交
  4. 14 2月, 2013 1 次提交
    • P
      net: Fix possible wrong checksum generation. · c9af6db4
      Pravin B Shelar 提交于
      Patch cef401de (net: fix possible wrong checksum
      generation) fixed wrong checksum calculation but it broke TSO by
      defining new GSO type but not a netdev feature for that type.
      net_gso_ok() would not allow hardware checksum/segmentation
      offload of such packets without the feature.
      
      Following patch fixes TSO and wrong checksum. This patch uses
      same logic that Eric Dumazet used. Patch introduces new flag
      SKBTX_SHARED_FRAG if at least one frag can be modified by
      the user. but SKBTX_SHARED_FRAG flag is kept in skb shared
      info tx_flags rather than gso_type.
      
      tx_flags is better compared to gso_type since we can have skb with
      shared frag without gso packet. It does not link SHARED_FRAG to
      GSO, So there is no need to define netdev feature for this.
      Signed-off-by: NPravin B Shelar <pshelar@nicira.com>
      Signed-off-by: NDavid S. Miller <davem@davemloft.net>
      c9af6db4
  5. 28 1月, 2013 1 次提交
    • E
      net: fix possible wrong checksum generation · cef401de
      Eric Dumazet 提交于
      Pravin Shelar mentioned that GSO could potentially generate
      wrong TX checksum if skb has fragments that are overwritten
      by the user between the checksum computation and transmit.
      
      He suggested to linearize skbs but this extra copy can be
      avoided for normal tcp skbs cooked by tcp_sendmsg().
      
      This patch introduces a new SKB_GSO_SHARED_FRAG flag, set
      in skb_shinfo(skb)->gso_type if at least one frag can be
      modified by the user.
      
      Typical sources of such possible overwrites are {vm}splice(),
      sendfile(), and macvtap/tun/virtio_net drivers.
      
      Tested:
      
      $ netperf -H 7.7.8.84
      MIGRATED TCP STREAM TEST from 0.0.0.0 (0.0.0.0) port 0 AF_INET to
      7.7.8.84 () port 0 AF_INET
      Recv   Send    Send
      Socket Socket  Message  Elapsed
      Size   Size    Size     Time     Throughput
      bytes  bytes   bytes    secs.    10^6bits/sec
      
       87380  16384  16384    10.00    3959.52
      
      $ netperf -H 7.7.8.84 -t TCP_SENDFILE
      TCP SENDFILE TEST from 0.0.0.0 (0.0.0.0) port 0 AF_INET to 7.7.8.84 ()
      port 0 AF_INET
      Recv   Send    Send
      Socket Socket  Message  Elapsed
      Size   Size    Size     Time     Throughput
      bytes  bytes   bytes    secs.    10^6bits/sec
      
       87380  16384  16384    10.00    3216.80
      
      Performance of the SENDFILE is impacted by the extra allocation and
      copy, and because we use order-0 pages, while the TCP_STREAM uses
      bigger pages.
      Reported-by: NPravin Shelar <pshelar@nicira.com>
      Signed-off-by: NEric Dumazet <edumazet@google.com>
      Signed-off-by: NDavid S. Miller <davem@davemloft.net>
      cef401de
  6. 13 8月, 2012 1 次提交
  7. 08 6月, 2012 1 次提交
  8. 12 5月, 2012 1 次提交
  9. 02 5月, 2012 5 次提交
  10. 14 2月, 2012 1 次提交
  11. 21 12月, 2011 1 次提交
  12. 24 11月, 2011 1 次提交
  13. 21 10月, 2011 5 次提交
  14. 21 9月, 2011 1 次提交
  15. 16 9月, 2011 1 次提交
  16. 07 7月, 2011 1 次提交
  17. 12 6月, 2011 1 次提交
    • J
      virtio_net: introduce VIRTIO_NET_HDR_F_DATA_VALID · 10a8d94a
      Jason Wang 提交于
      There's no need for the guest to validate the checksum if it have been
      validated by host nics. So this patch introduces a new flag -
      VIRTIO_NET_HDR_F_DATA_VALID which is used to bypass the checksum
      examing in guest. The backend (tap/macvtap) may set this flag when
      met skbs with CHECKSUM_UNNECESSARY to save cpu utilization.
      
      No feature negotiation is needed as old driver just ignore this flag.
      
      Iperf shows 12%-30% performance improvement for UDP traffic. For TCP,
      when gro is on no difference as it produces skb with partial
      checksum. But when gro is disabled, 20% or even higher improvement
      could be measured by netperf.
      Signed-off-by: NJason Wang <jasowang@redhat.com>
      Acked-by: NMichael S. Tsirkin <mst@redhat.com>
      Signed-off-by: NDavid S. Miller <davem@davemloft.net>
      10a8d94a
  18. 08 3月, 2011 1 次提交
  19. 28 1月, 2011 1 次提交
  20. 14 1月, 2011 1 次提交
    • E
      net: remove dev_txq_stats_fold() · 1ac9ad13
      Eric Dumazet 提交于
      After recent changes, (percpu stats on vlan/tunnels...), we dont need
      anymore per struct netdev_queue tx_bytes/tx_packets/tx_dropped counters.
      
      Only remaining users are ixgbe, sch_teql, gianfar & macvlan :
      
      1) ixgbe can be converted to use existing tx_ring counters.
      
      2) macvlan incremented txq->tx_dropped, it can use the
      dev->stats.tx_dropped counter.
      
      3) sch_teql : almost revert ab35cd4b (Use net_device internal stats)
          Now we have ndo_get_stats64(), use it, even for "unsigned long"
      fields (No need to bring back a struct net_device_stats)
      
      4) gianfar adds a stats structure per tx queue to hold
      tx_bytes/tx_packets
      
      This removes a lockdep warning (and possible lockup) in rndis gadget,
      calling dev_get_stats() from hard IRQ context.
      
      Ref: http://www.spinics.net/lists/netdev/msg149202.htmlReported-by: NNeil Jones <neiljay@gmail.com>
      Signed-off-by: NEric Dumazet <eric.dumazet@gmail.com>
      CC: Jarek Poplawski <jarkao2@gmail.com>
      CC: Alexander Duyck <alexander.h.duyck@intel.com>
      CC: Jeff Kirsher <jeffrey.t.kirsher@intel.com>
      CC: Sandeep Gopalpet <sandeep.kumar@freescale.com>
      CC: Michal Nazarewicz <mina86@mina86.com>
      Signed-off-by: NDavid S. Miller <davem@davemloft.net>
      1ac9ad13
  21. 17 12月, 2010 1 次提交
  22. 17 8月, 2010 1 次提交
  23. 23 7月, 2010 1 次提交
    • H
      macvtap: Limit packet queue length · 8a35747a
      Herbert Xu 提交于
      Mark Wagner reported OOM symptoms when sending UDP traffic over
      a macvtap link to a kvm receiver.
      
      This appears to be caused by the fact that macvtap packet queues
      are unlimited in length.  This means that if the receiver can't
      keep up with the rate of flow, then we will hit OOM. Of course
      it gets worse if the OOM killer then decides to kill the receiver.
      
      This patch imposes a cap on the packet queue length, in the same
      way as the tuntap driver, using the device TX queue length.
      
      Please note that macvtap currently has no way of giving congestion
      notification, that means the software device TX queue cannot be
      used and packets will always be dropped once the macvtap driver
      queue fills up.
      
      This shouldn't be a great problem for the scenario where macvtap
      is used to feed a kvm receiver, as the traffic is most likely
      external in origin so congestion notification can't be applied
      anyway.
      
      Of course, if anybody decides to complain about guest-to-guest
      UDP packet loss down the track, then we may have to revisit this.
      
      Incidentally, this patch also fixes a real memory leak when
      macvtap_get_queue fails.
      
      Chris Wright noticed that for this patch to work, we need a
      non-zero TX queue length.  This patch includes his work to change
      the default macvtap TX queue length to 500.
      Reported-by: NMark Wagner <mwagner@redhat.com>
      Signed-off-by: NHerbert Xu <herbert@gondor.apana.org.au>
      Acked-by: NChris Wright <chrisw@sous-sol.org>
      Acked-by: NArnd Bergmann <arnd@arndb.de>
      Signed-off-by: NDavid S. Miller <davem@davemloft.net>
      8a35747a
  24. 11 7月, 2010 1 次提交
  25. 04 5月, 2010 1 次提交
  26. 02 5月, 2010 1 次提交
    • E
      net: sock_def_readable() and friends RCU conversion · 43815482
      Eric Dumazet 提交于
      sk_callback_lock rwlock actually protects sk->sk_sleep pointer, so we
      need two atomic operations (and associated dirtying) per incoming
      packet.
      
      RCU conversion is pretty much needed :
      
      1) Add a new structure, called "struct socket_wq" to hold all fields
      that will need rcu_read_lock() protection (currently: a
      wait_queue_head_t and a struct fasync_struct pointer).
      
      [Future patch will add a list anchor for wakeup coalescing]
      
      2) Attach one of such structure to each "struct socket" created in
      sock_alloc_inode().
      
      3) Respect RCU grace period when freeing a "struct socket_wq"
      
      4) Change sk_sleep pointer in "struct sock" by sk_wq, pointer to "struct
      socket_wq"
      
      5) Change sk_sleep() function to use new sk->sk_wq instead of
      sk->sk_sleep
      
      6) Change sk_has_sleeper() to wq_has_sleeper() that must be used inside
      a rcu_read_lock() section.
      
      7) Change all sk_has_sleeper() callers to :
        - Use rcu_read_lock() instead of read_lock(&sk->sk_callback_lock)
        - Use wq_has_sleeper() to eventually wakeup tasks.
        - Use rcu_read_unlock() instead of read_unlock(&sk->sk_callback_lock)
      
      8) sock_wake_async() is modified to use rcu protection as well.
      
      9) Exceptions :
        macvtap, drivers/net/tun.c, af_unix use integrated "struct socket_wq"
      instead of dynamically allocated ones. They dont need rcu freeing.
      
      Some cleanups or followups are probably needed, (possible
      sk_callback_lock conversion to a spinlock for example...).
      Signed-off-by: NEric Dumazet <eric.dumazet@gmail.com>
      Signed-off-by: NDavid S. Miller <davem@davemloft.net>
      43815482
  27. 27 4月, 2010 1 次提交
  28. 21 4月, 2010 1 次提交
  29. 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
  30. 19 2月, 2010 3 次提交