android_kernel_motorola_sm6225/net
Kirill Tkhai f0b07bb151 net: Introduce net_rwsem to protect net_namespace_list
rtnl_lock() is used everywhere, and contention is very high.
When someone wants to iterate over alive net namespaces,
he/she has no a possibility to do that without exclusive lock.
But the exclusive rtnl_lock() in such places is overkill,
and it just increases the contention. Yes, there is already
for_each_net_rcu() in kernel, but it requires rcu_read_lock(),
and this can't be sleepable. Also, sometimes it may be need
really prevent net_namespace_list growth, so for_each_net_rcu()
is not fit there.

This patch introduces new rw_semaphore, which will be used
instead of rtnl_mutex to protect net_namespace_list. It is
sleepable and allows not-exclusive iterations over net
namespaces list. It allows to stop using rtnl_lock()
in several places (what is made in next patches) and makes
less the time, we keep rtnl_mutex. Here we just add new lock,
while the explanation of we can remove rtnl_lock() there are
in next patches.

Fine grained locks generally are better, then one big lock,
so let's do that with net_namespace_list, while the situation
allows that.

Signed-off-by: Kirill Tkhai <ktkhai@virtuozzo.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-03-29 13:47:53 -04:00
..
6lowpan
9p virtio: bugfixes 2018-02-15 14:29:27 -08:00
802 treewide: setup_timer() -> timer_setup() 2017-11-21 15:57:07 -08:00
8021q net: Drop pernet_operations::async 2018-03-27 13:18:09 -04:00
appletalk net: Use octal not symbolic permissions 2018-03-26 12:07:48 -04:00
atm net: Use octal not symbolic permissions 2018-03-26 12:07:48 -04:00
ax25 net: Use octal not symbolic permissions 2018-03-26 12:07:48 -04:00
batman-adv Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2018-03-23 11:31:58 -04:00
bluetooth net: Use octal not symbolic permissions 2018-03-26 12:07:48 -04:00
bpf bpf: fix null pointer deref in bpf_prog_test_run_xdp 2018-02-01 07:43:56 -08:00
bridge net: Drop pernet_operations::async 2018-03-27 13:18:09 -04:00
caif net: Drop pernet_operations::async 2018-03-27 13:18:09 -04:00
can net: Drop pernet_operations::async 2018-03-27 13:18:09 -04:00
ceph net: Use octal not symbolic permissions 2018-03-26 12:07:48 -04:00
core net: Introduce net_rwsem to protect net_namespace_list 2018-03-29 13:47:53 -04:00
dcb
dccp net: Drop pernet_operations::async 2018-03-27 13:18:09 -04:00
decnet net: Use octal not symbolic permissions 2018-03-26 12:07:48 -04:00
dns_resolver net: Use octal not symbolic permissions 2018-03-26 12:07:48 -04:00
dsa Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2018-03-23 11:31:58 -04:00
ethernet
hsr
ieee802154 net: Drop pernet_operations::async 2018-03-27 13:18:09 -04:00
ife
ipv4 Merge branch 'master' of git://git.kernel.org/pub/scm/linux/kernel/git/klassert/ipsec-next 2018-03-29 11:22:31 -04:00
ipv6 Merge branch 'master' of git://git.kernel.org/pub/scm/linux/kernel/git/klassert/ipsec-next 2018-03-29 11:22:31 -04:00
iucv Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2018-03-23 11:31:58 -04:00
kcm net: Drop pernet_operations::async 2018-03-27 13:18:09 -04:00
key net: Drop pernet_operations::async 2018-03-27 13:18:09 -04:00
l2tp net: Drop pernet_operations::async 2018-03-27 13:18:09 -04:00
l3mdev
lapb treewide: Remove TIMER_FUNC_TYPE and TIMER_DATA_TYPE casts 2017-11-21 16:35:54 -08:00
llc net: Use octal not symbolic permissions 2018-03-26 12:07:48 -04:00
mac80211 net: Use octal not symbolic permissions 2018-03-26 12:07:48 -04:00
mac802154
mpls net: Drop pernet_operations::async 2018-03-27 13:18:09 -04:00
ncsi net/ncsi: check for null return from call to nla_nest_start 2018-03-27 10:38:26 -04:00
netfilter net: Introduce net_rwsem to protect net_namespace_list 2018-03-29 13:47:53 -04:00
netlabel net/netlabel: Add list_next_rcu() in rcu_dereference(). 2017-11-18 10:32:41 +09:00
netlink net: Drop pernet_operations::async 2018-03-27 13:18:09 -04:00
netrom net: Use octal not symbolic permissions 2018-03-26 12:07:48 -04:00
nfc Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2018-02-19 18:46:11 -05:00
nsh
openvswitch net: Introduce net_rwsem to protect net_namespace_list 2018-03-29 13:47:53 -04:00
packet net: Drop pernet_operations::async 2018-03-27 13:18:09 -04:00
phonet net: Drop pernet_operations::async 2018-03-27 13:18:09 -04:00
psample
qrtr Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2018-03-06 01:20:46 -05:00
rds net: Drop pernet_operations::async 2018-03-27 13:18:09 -04:00
rfkill vfs: do bulk POLL* -> EPOLL* replacement 2018-02-11 14:34:03 -08:00
rose net: Use octal not symbolic permissions 2018-03-26 12:07:48 -04:00
rxrpc rxrpc: Trace call completion 2018-03-27 23:08:20 +01:00
sched net: Drop pernet_operations::async 2018-03-27 13:18:09 -04:00
sctp net: Drop pernet_operations::async 2018-03-27 13:18:09 -04:00
smc Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2018-03-23 11:31:58 -04:00
strparser strparser: Call sock_owned_by_user_nocheck 2017-12-28 14:28:22 -05:00
sunrpc net: Drop pernet_operations::async 2018-03-27 13:18:09 -04:00
switchdev
tipc net: Drop pernet_operations::async 2018-03-27 13:18:09 -04:00
tls tls: RX path for ktls 2018-03-23 12:25:54 -04:00
unix net: Drop pernet_operations::async 2018-03-27 13:18:09 -04:00
vmw_vsock net: make getname() functions return length rather than use int* parameter 2018-02-12 14:15:04 -05:00
wimax
wireless net: Introduce net_rwsem to protect net_namespace_list 2018-03-29 13:47:53 -04:00
x25 net: Use octal not symbolic permissions 2018-03-26 12:07:48 -04:00
xfrm Merge branch 'master' of git://git.kernel.org/pub/scm/linux/kernel/git/klassert/ipsec-next 2018-03-29 11:22:31 -04:00
compat.c
Kconfig Staging/IIO patches for 4.16-rc1 2018-02-01 09:51:57 -08:00
Makefile ipx: move Novell IPX protocol support into staging 2017-11-28 13:55:00 +01:00
socket.c Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2018-03-23 11:31:58 -04:00
sysctl_net.c net: Drop pernet_operations::async 2018-03-27 13:18:09 -04:00