1. 29 Oct, 2016 31 commits
  2. 28 Oct, 2016 8 commits
  3. 27 Oct, 2016 1 commit
    • Andrey Vagin's avatar
      net: skip genenerating uevents for network namespaces that are exiting · 002d8a1a
      Andrey Vagin authored
      No one can see these events, because a network namespace can not be
      destroyed, if it has sockets.
      
      Unlike other devices, uevent-s for network devices are generated
      only inside their network namespaces. They are filtered in
      kobj_bcast_filter()
      
      My experiments shows that net namespaces are destroyed more 30% faster
      with this optimization.
      
      Here is a perf output for destroying network namespaces without this
      patch.
      
      -   94.76%     0.02%  kworker/u48:1  [kernel.kallsyms]     [k] cleanup_net
         - 94.74% cleanup_net
            - 94.64% ops_exit_list.isra.4
               - 41.61% default_device_exit_batch
                  - 41.47% unregister_netdevice_many
                     - rollback_registered_many
                        - 40.36% netdev_unregister_kobject
                           - 14.55% device_del
                              + 13.71% kobject_uevent
                           - 13.04% netdev_queue_update_kobjects
                              + 12.96% kobject_put
                           - 12.72% net_rx_queue_update_kobjects
                                kobject_put
                              - kobject_release
                                 + 12.69% kobject_uevent
                        + 0.80% call_netdevice_notifiers_info
               + 19.57% nfsd_exit_net
               + 11.15% tcp_net_metrics_exit
               + 8.25% rpcsec_gss_exit_net
      
      It's very critical to optimize the exit path for network namespaces,
      because they are destroyed under net_mutex and many namespaces can be
      destroyed for one iteration.
      
      v2: use dev_set_uevent_suppress()
      
      Cc: Cong Wang <xiyou.wangcong@gmail.com>
      Cc: "David S. Miller" <davem@davemloft.net>
      Cc: Eric W. Biederman <ebiederm@xmission.com>
      Signed-off-by: default avatarAndrei Vagin <avagin@openvz.org>
      Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
      002d8a1a