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  1. 04 5月, 2016 15 次提交
  3. 03 5月, 2016 19 次提交
  5. 02 5月, 2016 2 次提交
  7. 30 4月, 2016 1 次提交
  9. 29 4月, 2016 3 次提交
    • F
      net: dsa: Provide CPU port statistics to master netdev · badf3ada
      由 Florian Fainelli 提交于 
      This patch overloads the DSA master netdev, aka CPU Ethernet MAC to also
include switch-side statistics, which is useful for debugging purposes,
when the switch is not properly connected to the Ethernet MAC (duplex
mismatch, (RG)MII electrical issues etc.).

We accomplish this by retaining the original copy of the master netdev's
ethtool_ops, and just overload the 3 operations we care about:
get_sset_count, get_strings and get_ethtool_stats so as to intercept
these calls and call into the original master_netdev ethtool_ops, plus
our own.

We take this approach as opposed to providing a set of DSA helper
functions that would retrive the CPU port's statistics, because the
entire purpose of DSA is to allow unmodified Ethernet MAC drivers to be
used as CPU conduit interfaces, therefore, statistics overlay in such
drivers would simply not scale.

The new ethtool -S <iface> output would therefore look like this now:
<iface> statistics
p<2 digits cpu port number>_<switch MIB counter names>
Signed-off-by: NFlorian Fainelli <f.fainelli@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>
      badf3ada
    • E
      tcp: give prequeue mode some care · 0cef6a4c
      由 Eric Dumazet 提交于 
      TCP prequeue goal is to defer processing of incoming packets
to user space thread currently blocked in a recvmsg() system call.

Intent is to spend less time processing these packets on behalf
of softirq handler, as softirq handler is unfair to normal process
scheduler decisions, as it might interrupt threads that do not
even use networking.

Current prequeue implementation has following issues :

1) It only checks size of the prequeue against sk_rcvbuf

   It was fine 15 years ago when sk_rcvbuf was in the 64KB vicinity.
   But we now have ~8MB values to cope with modern networking needs.
   We have to add sk_rmem_alloc in the equation, since out of order
   packets can definitely use up to sk_rcvbuf memory themselves.

2) Even with a fixed memory truesize check, prequeue can be filled
   by thousands of packets. When prequeue needs to be flushed, either
   from sofirq context (in tcp_prequeue() or timer code), or process
   context (in tcp_prequeue_process()), this adds a latency spike
   which is often not desirable.
   I added a fixed limit of 32 packets, as this translated to a max
   flush time of 60 us on my test hosts.

   Also note that all packets in prequeue are not accounted for tcp_mem,
   since they are not charged against sk_forward_alloc at this point.
   This is probably not a big deal.

Note that this might increase LINUX_MIB_TCPPREQUEUEDROPPED counts,
which is misnamed, as packets are not dropped at all, but rather pushed
to the stack (where they can be either consumed or dropped)
Signed-off-by: NEric Dumazet <edumazet@google.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>
      0cef6a4c
    • D
      tipc: remove an unnecessary NULL check · b4358657
      由 Dan Carpenter 提交于 
      This is never called with a NULL "buf" and anyway, we dereference 's' on
the lines before so it would Oops before we reach the check.
Signed-off-by: NDan Carpenter <dan.carpenter@oracle.com>
Acked-by: NYing Xue <ying.xue@windriver.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>
      b4358657