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  1. 05 Apr, 2011 8 commits
    • Tom Herbert's avatar
      net: Allow no-cache copy from user on transmit · c6e1a0d1
      Tom Herbert authored 
      This patch uses __copy_from_user_nocache on transmit to bypass data
cache for a performance improvement.  skb_add_data_nocache and
skb_copy_to_page_nocache can be called by sendmsg functions to use
this feature, initial support is in tcp_sendmsg.  This functionality is
configurable per device using ethtool.

Presumably, this feature would only be useful when the driver does
not touch the data.  The feature is turned on by default if a device
indicates that it does some form of checksum offload; it is off by
default for devices that do no checksum offload or indicate no checksum
is necessary.  For the former case copy-checksum is probably done
anyway, in the latter case the device is likely loopback in which case
the no cache copy is probably not beneficial.

This patch was tested using 200 instances of netperf TCP_RR with
1400 byte request and one byte reply.  Platform is 16 core AMD x86.

No-cache copy disabled:
   672703 tps, 97.13% utilization
   50/90/99% latency:244.31 484.205 1028.41

No-cache copy enabled:
   702113 tps, 96.16% utilization,
   50/90/99% latency 238.56 467.56 956.955

Using 14000 byte request and response sizes demonstrate the
effects more dramatically:

No-cache copy disabled:
   79571 tps, 34.34 %utlization
   50/90/95% latency 1584.46 2319.59 5001.76

No-cache copy enabled:
   83856 tps, 34.81% utilization
   50/90/95% latency 2508.42 2622.62 2735.88

Note especially the effect on latency tail (95th percentile).

This seems to provide a nice performance improvement and is
consistent in the tests I ran.  Presumably, this would provide
the greatest benfits in the presence of an application workload
stressing the cache and a lot of transmit data happening.
Signed-off-by: default avatarTom Herbert <therbert@google.com>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      c6e1a0d1
    • stephen hemminger's avatar
      bridge: range check STP parameters · 14f98f25
      stephen hemminger authored 
      Apply restrictions on STP parameters based 802.1D 1998 standard.
   * Fixes missing locking in set path cost ioctl
   * Uses common code for both ioctl and sysfs

This is based on an earlier patch Sasikanth V but with overhaul.

Note:
1. It does NOT enforce the restriction on the relationship max_age and
   forward delay or hello time because in existing implementation these are
   set as independant operations.

2. If STP is disabled, there is no restriction on forward delay

3. No restriction on holding time because users use Linux code to act
   as hub or be sticky.

4. Although standard allow 0-255, Linux only allows 0-63 for port priority
   because more bits are reserved for port number.
Signed-off-by: default avatarStephen Hemminger <shemminger@vyatta.com>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      14f98f25
    • stephen hemminger's avatar
      bridge: allow creating bridge devices with netlink · bb900b27
      stephen hemminger authored 
      Add netlink device ops to allow creating bridge device via netlink.
This works in a manner similar to vlan, macvlan and bonding.

Example:
  # ip link add link dev br0 type bridge
  # ip link del dev br0

The change required rearranging initializtion code to deal with
being called by create link. Most of the initialization happens
in br_dev_setup, but allocation of stats is done in ndo_init callback
to deal with allocation failure. Sysfs setup has to wait until
after the network device kobject is registered.
Signed-off-by: default avatarStephen Hemminger <shemminger@vyatta.com>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      bb900b27
    • stephen hemminger's avatar
      bridge: allow creating/deleting fdb entries via netlink · 36fd2b63
      stephen hemminger authored 
      Use RTM_NEWNEIGH and RTM_DELNEIGH to allow updating of entries
in bridge forwarding table. This allows manipulating static entries
which is not possible with existing tools.

Example (using bridge extensions to iproute2)
   # br fdb add 00:02:03:04:05:06 dev eth0
Signed-off-by: default avatarStephen Hemminger <shemminger@vyatta.com>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      36fd2b63
    • stephen hemminger's avatar
      bridge: add netlink notification on forward entry changes · b078f0df
      stephen hemminger authored 
      This allows applications to query and monitor bridge forwarding
table in the same method used for neighbor table. The forward table
entries are returned in same structure format as used by the ioctl.
If more information is desired in future, the netlink method is
extensible.

Example (using bridge extensions to iproute2)
  # br monitor
Signed-off-by: default avatarStephen Hemminger <shemminger@vyatta.com>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      b078f0df
    • stephen hemminger's avatar
      bridge: split rcu and no-rcu cases of fdb lookup · 664de48b
      stephen hemminger authored 
      In some cases, look up of forward database entry is done with RCU;
and for others no RCU is needed because of locking. Split the two
cases into two differnt loops (and take off inline).
Signed-off-by: default avatarStephen Hemminger <shemminger@vyatta.com>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      664de48b
    • stephen hemminger's avatar
      bridge: track last used time in forwarding table · 7cd8861a
      stephen hemminger authored 
      Adds tracking the last used time in forwarding table.
Rename ageing_timer to updated to better describe it.
Signed-off-by: default avatarStephen Hemminger <shemminger@vyatta.com>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      7cd8861a
    • stephen hemminger's avatar
      bridge: change arguments to fdb_create · 03e9b64b
      stephen hemminger authored 
      Later patch provides ability to create non-local static entry.
To make this easier move the updating of the flag values to
after the code that creates entry.
Signed-off-by: default avatarStephen Hemminger <shemminger@vyatta.com>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      03e9b64b
  3. 04 Apr, 2011 6 commits
  5. 03 Apr, 2011 2 commits
  7. 02 Apr, 2011 13 commits
  9. 01 Apr, 2011 5 commits
  11. 31 Mar, 2011 6 commits
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