linux/net/core
Andrey Vagin 002d8a1a6c net: skip genenerating uevents for network namespaces that are exiting
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: Andrei Vagin <avagin@openvz.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2016-10-27 17:14:47 -04:00
..
Makefile net: add a hardware buffer management helper API 2016-03-14 12:19:46 -04:00
datagram.c net/socket: factor out helpers for memory and queue manipulation 2016-10-22 17:05:05 -04:00
dev.c net: dev: Improve debug statements for adjacency tracking 2016-10-18 11:45:00 -04:00
dev_addr_lists.c net: fix spelling for synchronized 2014-11-18 15:26:32 -05:00
dev_ioctl.c dev_ioctl: use sizeof(x) instead of sizeof x 2014-11-18 15:27:32 -05:00
devlink.c genetlink: mark families as __ro_after_init 2016-10-27 16:16:09 -04:00
drop_monitor.c genetlink: mark families as __ro_after_init 2016-10-27 16:16:09 -04:00
dst.c net: add dst_cache to ovs vxlan lwtunnel 2016-02-16 20:21:48 -05:00
dst_cache.c net: dst_cache_per_cpu_dst_set() can be static 2016-03-18 17:45:08 -04:00
ethtool.c sctp: Add GSO support 2016-06-03 19:37:21 -04:00
fib_rules.c fib_rules: Added NLM_F_EXCL support to fib_nl_newrule 2016-06-30 08:23:19 -04:00
filter.c bpf: add helper for retrieving current numa node id 2016-10-22 17:05:52 -04:00
flow.c flowcache: Avoid OOM condition under preasure 2016-03-17 10:28:42 +01:00
flow_dissector.c Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2016-09-12 15:52:44 -07:00
gen_estimator.c net: sched: do not acquire qdisc spinlock in qdisc/class stats dump 2016-06-07 16:37:14 -07:00
gen_stats.c Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2016-06-10 11:52:24 -07:00
hwbm.c net: hwbm: Fix unbalanced spinlock in error case 2016-05-25 12:35:09 -07:00
link_watch.c dev: introduce dev_get_iflink() 2015-04-02 14:04:59 -04:00
lwtunnel.c lwtunnel: Add destroy state operation 2016-10-15 17:33:41 -04:00
neighbour.c neigh: allow admin to set NUD_STALE 2016-08-08 15:36:38 -07:00
net-procfs.c net: remove NETDEV_TX_LOCKED support 2016-04-26 15:53:05 -04:00
net-sysfs.c net: skip genenerating uevents for network namespaces that are exiting 2016-10-27 17:14:47 -04:00
net-sysfs.h net: netdev_kobject_init: annotate with __init 2014-01-05 20:27:54 -05:00
net-traces.c net: IPv6 fib lookup tracepoint 2015-11-22 11:54:10 -05:00
net_namespace.c net: allow to kill a task which waits net_mutex in copy_new_ns 2016-10-23 17:33:39 -04:00
netclassid_cgroup.c core: remove unneded headers for net cgroup controllers. 2016-02-17 15:31:27 -05:00
netevent.c netevent: remove automatic variable in register_netevent_notifier() 2015-05-31 00:03:21 -07:00
netpoll.c net: tracepoint napi:napi_poll add work and budget 2016-07-09 18:05:02 -04:00
netprio_cgroup.c core: remove unneded headers for net cgroup controllers. 2016-02-17 15:31:27 -05:00
pktgen.c net: pktgen: fix pkt_size 2016-10-03 01:29:57 -04:00
ptp_classifier.c ptp: Change ptp_class to a proper bitmask 2015-11-03 11:08:22 -05:00
request_sock.c tcp: restore fastopen operations 2015-10-05 03:19:06 -07:00
rtnetlink.c net: rtnl: info leak in rtnl_fill_vfinfo() 2016-10-13 12:12:04 -04:00
scm.c unix: correctly track in-flight fds in sending process user_struct 2016-02-08 10:30:42 -05:00
secure_seq.c net: remove a sparse error in secure_dccpv6_sequence_number() 2015-05-25 22:55:37 -04:00
skbuff.c Merge branch 'work.splice_read' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2016-10-07 15:36:58 -07:00
sock.c net/socket: factor out helpers for memory and queue manipulation 2016-10-22 17:05:05 -04:00
sock_diag.c sock_diag: align nlattr properly when needed 2016-04-26 12:00:48 -04:00
sock_reuseport.c soreuseport: fix NULL ptr dereference SO_REUSEPORT after bind 2016-01-19 14:44:23 -05:00
stream.c net: do not export sk_stream_write_space 2016-09-28 20:32:38 -04:00
sysctl_net_core.c bpf: add generic constant blinding for use in jits 2016-05-16 13:49:32 -04:00
timestamping.c net: skb_defer_rx_timestamp should check for phydev before setting up classify 2015-07-09 14:17:15 -07:00
tso.c net: tso: add support for IPv6 2015-10-26 22:24:22 -07:00
utils.c net: the space is required before the open parenthesis '(' 2016-06-29 05:15:14 -04:00