1. 05 11月, 2015 1 次提交
  2. 23 10月, 2015 2 次提交
  3. 16 10月, 2015 1 次提交
  4. 07 10月, 2015 1 次提交
  5. 30 9月, 2015 4 次提交
  6. 24 9月, 2015 1 次提交
    • N
      netpoll: Close race condition between poll_one_napi and napi_disable · 2d8bff12
      Neil Horman 提交于
      Drivers might call napi_disable while not holding the napi instance poll_lock.
      In those instances, its possible for a race condition to exist between
      poll_one_napi and napi_disable.  That is to say, poll_one_napi only tests the
      NAPI_STATE_SCHED bit to see if there is work to do during a poll, and as such
      the following may happen:
      
      CPU0				CPU1
      ndo_tx_timeout			napi_poll_dev
       napi_disable			 poll_one_napi
        test_and_set_bit (ret 0)
      				  test_bit (ret 1)
         reset adapter		   napi_poll_routine
      
      If the adapter gets a tx timeout without a napi instance scheduled, its possible
      for the adapter to think it has exclusive access to the hardware  (as the napi
      instance is now scheduled via the napi_disable call), while the netpoll code
      thinks there is simply work to do.  The result is parallel hardware access
      leading to corrupt data structures in the driver, and a crash.
      
      Additionaly, there is another, more critical race between netpoll and
      napi_disable.  The disabled napi state is actually identical to the scheduled
      state for a given napi instance.  The implication being that, if a napi instance
      is disabled, a netconsole instance would see the napi state of the device as
      having been scheduled, and poll it, likely while the driver was dong something
      requiring exclusive access.  In the case above, its fairly clear that not having
      the rings in a state ready to be polled will cause any number of crashes.
      
      The fix should be pretty easy.  netpoll uses its own bit to indicate that that
      the napi instance is in a state of being serviced by netpoll (NAPI_STATE_NPSVC).
      We can just gate disabling on that bit as well as the sched bit.  That should
      prevent netpoll from conducting a napi poll if we convert its set bit to a
      test_and_set_bit operation to provide mutual exclusion
      
      Change notes:
      V2)
      	Remove a trailing whtiespace
      	Resubmit with proper subject prefix
      
      V3)
      	Clean up spacing nits
      Signed-off-by: NNeil Horman <nhorman@tuxdriver.com>
      CC: "David S. Miller" <davem@davemloft.net>
      CC: jmaxwell@redhat.com
      Tested-by: jmaxwell@redhat.com
      Signed-off-by: NDavid S. Miller <davem@davemloft.net>
      2d8bff12
  7. 18 9月, 2015 3 次提交
  8. 31 8月, 2015 1 次提交
  9. 28 8月, 2015 4 次提交
  10. 24 8月, 2015 1 次提交
  11. 18 8月, 2015 3 次提交
  12. 14 8月, 2015 1 次提交
  13. 21 7月, 2015 2 次提交
  14. 16 7月, 2015 1 次提交
  15. 16 6月, 2015 1 次提交
  16. 02 6月, 2015 1 次提交
  17. 14 5月, 2015 2 次提交
    • P
      netfilter: add netfilter ingress hook after handle_ing() under unique static key · e687ad60
      Pablo Neira 提交于
      This patch adds the Netfilter ingress hook just after the existing tc ingress
      hook, that seems to be the consensus solution for this.
      
      Note that the Netfilter hook resides under the global static key that enables
      ingress filtering. Nonetheless, Netfilter still also has its own static key for
      minimal impact on the existing handle_ing().
      
      * Without this patch:
      
      Result: OK: 6216490(c6216338+d152) usec, 100000000 (60byte,0frags)
        16086246pps 7721Mb/sec (7721398080bps) errors: 100000000
      
          42.46%  kpktgend_0   [kernel.kallsyms]   [k] __netif_receive_skb_core
          25.92%  kpktgend_0   [kernel.kallsyms]   [k] kfree_skb
           7.81%  kpktgend_0   [pktgen]            [k] pktgen_thread_worker
           5.62%  kpktgend_0   [kernel.kallsyms]   [k] ip_rcv
           2.70%  kpktgend_0   [kernel.kallsyms]   [k] netif_receive_skb_internal
           2.34%  kpktgend_0   [kernel.kallsyms]   [k] netif_receive_skb_sk
           1.44%  kpktgend_0   [kernel.kallsyms]   [k] __build_skb
      
      * With this patch:
      
      Result: OK: 6214833(c6214731+d101) usec, 100000000 (60byte,0frags)
        16090536pps 7723Mb/sec (7723457280bps) errors: 100000000
      
          41.23%  kpktgend_0      [kernel.kallsyms]  [k] __netif_receive_skb_core
          26.57%  kpktgend_0      [kernel.kallsyms]  [k] kfree_skb
           7.72%  kpktgend_0      [pktgen]           [k] pktgen_thread_worker
           5.55%  kpktgend_0      [kernel.kallsyms]  [k] ip_rcv
           2.78%  kpktgend_0      [kernel.kallsyms]  [k] netif_receive_skb_internal
           2.06%  kpktgend_0      [kernel.kallsyms]  [k] netif_receive_skb_sk
           1.43%  kpktgend_0      [kernel.kallsyms]  [k] __build_skb
      
      * Without this patch + tc ingress:
      
              tc filter add dev eth4 parent ffff: protocol ip prio 1 \
                      u32 match ip dst 4.3.2.1/32
      
      Result: OK: 9269001(c9268821+d179) usec, 100000000 (60byte,0frags)
        10788648pps 5178Mb/sec (5178551040bps) errors: 100000000
      
          40.99%  kpktgend_0   [kernel.kallsyms]  [k] __netif_receive_skb_core
          17.50%  kpktgend_0   [kernel.kallsyms]  [k] kfree_skb
          11.77%  kpktgend_0   [cls_u32]          [k] u32_classify
           5.62%  kpktgend_0   [kernel.kallsyms]  [k] tc_classify_compat
           5.18%  kpktgend_0   [pktgen]           [k] pktgen_thread_worker
           3.23%  kpktgend_0   [kernel.kallsyms]  [k] tc_classify
           2.97%  kpktgend_0   [kernel.kallsyms]  [k] ip_rcv
           1.83%  kpktgend_0   [kernel.kallsyms]  [k] netif_receive_skb_internal
           1.50%  kpktgend_0   [kernel.kallsyms]  [k] netif_receive_skb_sk
           0.99%  kpktgend_0   [kernel.kallsyms]  [k] __build_skb
      
      * With this patch + tc ingress:
      
              tc filter add dev eth4 parent ffff: protocol ip prio 1 \
                      u32 match ip dst 4.3.2.1/32
      
      Result: OK: 9308218(c9308091+d126) usec, 100000000 (60byte,0frags)
        10743194pps 5156Mb/sec (5156733120bps) errors: 100000000
      
          42.01%  kpktgend_0   [kernel.kallsyms]   [k] __netif_receive_skb_core
          17.78%  kpktgend_0   [kernel.kallsyms]   [k] kfree_skb
          11.70%  kpktgend_0   [cls_u32]           [k] u32_classify
           5.46%  kpktgend_0   [kernel.kallsyms]   [k] tc_classify_compat
           5.16%  kpktgend_0   [pktgen]            [k] pktgen_thread_worker
           2.98%  kpktgend_0   [kernel.kallsyms]   [k] ip_rcv
           2.84%  kpktgend_0   [kernel.kallsyms]   [k] tc_classify
           1.96%  kpktgend_0   [kernel.kallsyms]   [k] netif_receive_skb_internal
           1.57%  kpktgend_0   [kernel.kallsyms]   [k] netif_receive_skb_sk
      
      Note that the results are very similar before and after.
      
      I can see gcc gets the code under the ingress static key out of the hot path.
      Then, on that cold branch, it generates the code to accomodate the netfilter
      ingress static key. My explanation for this is that this reduces the pressure
      on the instruction cache for non-users as the new code is out of the hot path,
      and it comes with minimal impact for tc ingress users.
      
      Using gcc version 4.8.4 on:
      
      Architecture:          x86_64
      CPU op-mode(s):        32-bit, 64-bit
      Byte Order:            Little Endian
      CPU(s):                8
      [...]
      L1d cache:             16K
      L1i cache:             64K
      L2 cache:              2048K
      L3 cache:              8192K
      Signed-off-by: NPablo Neira Ayuso <pablo@netfilter.org>
      Acked-by: NAlexei Starovoitov <ast@plumgrid.com>
      Signed-off-by: NDavid S. Miller <davem@davemloft.net>
      e687ad60
    • J
      net: move __skb_tx_hash to dev.c · 5605c762
      Jiri Pirko 提交于
      __skb_tx_hash function has no relation to flow_dissect so just move it
      to dev.c
      Signed-off-by: NJiri Pirko <jiri@resnulli.us>
      Signed-off-by: NDavid S. Miller <davem@davemloft.net>
      5605c762
  18. 13 5月, 2015 3 次提交
  19. 12 5月, 2015 1 次提交
  20. 11 5月, 2015 1 次提交
    • D
      net: sched: further simplify handle_ing · d2788d34
      Daniel Borkmann 提交于
      Ingress qdisc has no other purpose than calling into tc_classify()
      that executes attached classifier(s) and action(s).
      
      It has a 1:1 relationship to dev->ingress_queue. After having commit
      087c1a60 ("net: sched: run ingress qdisc without locks") removed
      the central ingress lock, one major contention point is gone.
      
      The extra indirection layers however, are not necessary for calling
      into ingress qdisc. pktgen calling locally into netif_receive_skb()
      with a dummy u32, single CPU result on a Supermicro X10SLM-F, Xeon
      E3-1240: before ~21,1 Mpps, after patch ~22,9 Mpps.
      
      We can redirect the private classifier list to the netdev directly,
      without changing any classifier API bits (!) and execute on that from
      handle_ing() side. The __QDISC_STATE_DEACTIVATE test can be removed,
      ingress qdisc doesn't have a queue and thus dev_deactivate_queue()
      is also not applicable, ingress_cl_list provides similar behaviour.
      In other words, ingress qdisc acts like TCQ_F_BUILTIN qdisc.
      
      One next possible step is the removal of the dev's ingress (dummy)
      netdev_queue, and to only have the list member in the netdevice
      itself.
      
      Note, the filter chain is RCU protected and individual filter elements
      are being kfree'd by sched subsystem after RCU grace period. RCU read
      lock is being held by __netif_receive_skb_core().
      
      Joint work with Alexei Starovoitov.
      Signed-off-by: NDaniel Borkmann <daniel@iogearbox.net>
      Signed-off-by: NAlexei Starovoitov <ast@plumgrid.com>
      Signed-off-by: NDavid S. Miller <davem@davemloft.net>
      d2788d34
  21. 30 4月, 2015 1 次提交
    • N
      bridge/nl: remove wrong use of NLM_F_MULTI · 46c264da
      Nicolas Dichtel 提交于
      NLM_F_MULTI must be used only when a NLMSG_DONE message is sent. In fact,
      it is sent only at the end of a dump.
      
      Libraries like libnl will wait forever for NLMSG_DONE.
      
      Fixes: e5a55a89 ("net: create generic bridge ops")
      Fixes: 815cccbf ("ixgbe: add setlink, getlink support to ixgbe and ixgbevf")
      CC: John Fastabend <john.r.fastabend@intel.com>
      CC: Sathya Perla <sathya.perla@emulex.com>
      CC: Subbu Seetharaman <subbu.seetharaman@emulex.com>
      CC: Ajit Khaparde <ajit.khaparde@emulex.com>
      CC: Jeff Kirsher <jeffrey.t.kirsher@intel.com>
      CC: intel-wired-lan@lists.osuosl.org
      CC: Jiri Pirko <jiri@resnulli.us>
      CC: Scott Feldman <sfeldma@gmail.com>
      CC: Stephen Hemminger <stephen@networkplumber.org>
      CC: bridge@lists.linux-foundation.org
      Signed-off-by: NNicolas Dichtel <nicolas.dichtel@6wind.com>
      Signed-off-by: NDavid S. Miller <davem@davemloft.net>
      46c264da
  22. 23 4月, 2015 2 次提交
  23. 18 4月, 2015 1 次提交
  24. 14 4月, 2015 1 次提交