linux/net/ipv4
Eric Dumazet 573636cbaf [PATCH] net: remove superfluous call to synchronize_net()
inet_register_protosw() function is responsible for adding a new
inet protocol into a global table (inetsw[]) that is used with RCU rules.

As soon as the store of the pointer is done, other cpus might see
this new protocol in inetsw[], so we have to make sure new protocol
is ready for use. All pending memory updates should thus be committed
to memory before setting the pointer.
This is correctly done using rcu_assign_pointer()

synchronize_net() is typically used at unregister time, after
unsetting the pointer, to make sure no other cpu is still using
the object we want to dismantle. Using it at register time
is only adding an artificial delay that could hide a real bug,
and this bug could popup if/when synchronize_rcu() can proceed
faster than now.

This saves about 13 ms on boot time on a HZ=1000 8 cpus machine  ;) 
(4 calls to inet_register_protosw(), and about 3200 us per call)

Signed-off-by: Eric Dumazet <dada1@cosmosbay.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2009-04-17 04:52:48 -07:00
..
netfilter netfilter: nf_nat: add support for persistent mappings 2009-04-16 18:33:01 +02:00
af_inet.c [PATCH] net: remove superfluous call to synchronize_net() 2009-04-17 04:52:48 -07:00
ah4.c netns xfrm: AH/ESP in netns! 2008-11-25 17:59:27 -08:00
arp.c ipv4: arp announce, arp_proxy and windows ip conflict verification 2009-03-13 16:02:07 -07:00
cipso_ipv4.c netlabel: Label incoming TCP connections correctly in SELinux 2009-03-28 15:01:36 +11:00
datagram.c mib: add net to IP_INC_STATS_BH 2008-07-16 20:20:11 -07:00
devinet.c netlink: change nlmsg_notify() return value logic 2009-02-24 23:18:28 -08:00
esp4.c netns xfrm: AH/ESP in netns! 2008-11-25 17:59:27 -08:00
fib_frontend.c ip: add loose reverse path filtering 2009-02-22 19:54:45 -08:00
fib_hash.c net: clean up net/ipv4/fib_frontend.c fib_hash.c ip_gre.c 2008-11-03 00:25:16 -08:00
fib_lookup.h [IPV4] FIB_HASH: Reduce memory needs and speedup lookups 2008-01-28 15:02:46 -08:00
fib_rules.c net: add fib_rules_ops to flush_cache method 2008-07-05 19:01:28 -07:00
fib_semantics.c netlink: change nlmsg_notify() return value logic 2009-02-24 23:18:28 -08:00
fib_trie.c net: replace NIPQUAD() in net/ipv4/ net/ipv6/ 2008-10-31 00:53:57 -07:00
icmp.c netns: Fix icmp shutdown. 2009-03-03 01:14:15 -08:00
igmp.c netns: igmp: make /proc/net/{igmp,mcfilter} per netns 2008-12-25 16:42:51 -08:00
inet_connection_sock.c net: move bsockets outside of read only beginning of struct inet_hashinfo 2009-02-01 12:31:33 -08:00
inet_diag.c net: Convert TCP/DCCP listening hash tables to use RCU 2008-11-23 17:22:55 -08:00
inet_fragment.c inet fragments: fix sparse warning: context imbalance 2009-02-26 23:13:35 -08:00
inet_hashtables.c net: move bsockets outside of read only beginning of struct inet_hashinfo 2009-02-01 12:31:33 -08:00
inet_lro.c include/net net/ - csum_partial - remove unnecessary casts 2008-11-19 15:44:53 -08:00
inet_timewait_sock.c net: convert TCP/DCCP ehash rwlocks to spinlocks 2008-11-20 20:39:09 -08:00
inetpeer.c net: clean up net/ipv4/ah4.c esp4.c fib_semantics.c inet_connection_sock.c inetpeer.c ip_output.c 2008-11-03 00:23:42 -08:00
ip_forward.c net: reduce structures when XFRM=n 2008-10-28 13:24:06 -07:00
ip_fragment.c netns: oops in ip[6]_frag_reasm incrementing stats 2009-03-18 23:26:11 -07:00
ip_gre.c gre: used time_before for comparing jiffies 2009-02-24 23:34:48 -08:00
ip_input.c Merge branch 'master' of master.kernel.org:/pub/scm/linux/kernel/git/davem/net-2.6 2008-11-18 23:38:23 -08:00
ip_options.c cipso: Add support for native local labeling and fixup mapping names 2008-10-10 10:16:34 -04:00
ip_output.c ip: support for TX timestamps on UDP and RAW sockets 2009-02-15 22:43:38 -08:00
ip_sockglue.c net: ip_sockglue.c add static, annotate ports' endianness 2008-11-20 01:54:27 -08:00
ipcomp.c netns xfrm: state lookup in netns 2008-11-25 17:30:50 -08:00
ipconfig.c net: replace uses of __constant_{endian} 2009-02-01 00:45:17 -08:00
ipip.c ipip: used time_before for comparing jiffies 2009-02-24 23:36:47 -08:00
ipmr.c ipmr: use goto to common label instead of opencoding 2009-02-06 23:46:51 -08:00
Kconfig Doc: Refer to ip-sysctl.txt for strict vs. loose rp_filter mode 2009-02-24 03:47:42 -08:00
Makefile IPVS: Move IPVS to net/netfilter/ipvs 2008-10-07 08:38:24 +11:00
netfilter.c Merge branch 'master' of git://git.kernel.org/pub/scm/linux/kernel/git/kaber/nf-next-2.6 2008-11-28 02:19:15 -08:00
proc.c net: replace commatas with semicolons 2009-02-16 00:08:56 -08:00
protocol.c net: remove CVS keywords 2008-06-11 21:00:38 -07:00
raw.c ip: support for TX timestamps on UDP and RAW sockets 2009-02-15 22:43:38 -08:00
route.c Merge branch 'core/percpu' into percpu-cpumask-x86-for-linus-2 2009-03-27 17:28:43 +01:00
syncookies.c lsm: Relocate the IPv4 security_inet_conn_request() hooks 2009-03-28 15:01:36 +11:00
sysctl_net_ipv4.c net: '&' redux 2008-11-03 18:21:05 -08:00
tcp_bic.c tcp: add helper for AI algorithm 2009-03-02 03:00:15 -08:00
tcp_cong.c tcp: add helper for AI algorithm 2009-03-02 03:00:15 -08:00
tcp_cubic.c tcp: add helper for AI algorithm 2009-03-02 03:00:15 -08:00
tcp_diag.c net: inet_diag_handler structs can be const 2008-11-19 15:43:27 -08:00
tcp_highspeed.c [TCP]: Cong.ctrl modules: remove unused good_ack from cong_avoid 2008-01-28 14:55:41 -08:00
tcp_htcp.c htcp: merge icsk_ca_state compare 2009-03-02 03:00:14 -08:00
tcp_hybla.c tcp: Fix tcp_hybla zero congestion window growth with small rho and large cwnd. 2008-10-07 15:58:17 -07:00
tcp_illinois.c [TCP]: Cong.ctrl modules: remove unused good_ack from cong_avoid 2008-01-28 14:55:41 -08:00
tcp_input.c tcp: fix >2 iw selection 2009-04-14 02:08:53 -07:00
tcp_ipv4.c lsm: Relocate the IPv4 security_inet_conn_request() hooks 2009-03-28 15:01:36 +11:00
tcp_lp.c [TCP]: Cong.ctrl modules: remove unused good_ack from cong_avoid 2008-01-28 14:55:41 -08:00
tcp_minisocks.c tcp: consolidate paws check 2009-03-15 20:09:52 -07:00
tcp_output.c tcp: miscounts due to tcp_fragment pcount reset 2009-04-02 16:31:45 -07:00
tcp_probe.c tcp: '< 0' test on unsigned 2009-03-13 16:05:14 -07:00
tcp_scalable.c tcp: add helper for AI algorithm 2009-03-02 03:00:15 -08:00
tcp_timer.c tcp: cleanup ca_state mess in tcp_timer 2009-03-02 03:00:13 -08:00
tcp_vegas.c tcp: tcp_vegas cong avoid fix 2008-12-09 00:13:04 -08:00
tcp_vegas.h
tcp_veno.c tcp: add helper for AI algorithm 2009-03-02 03:00:15 -08:00
tcp_westwood.c
tcp_yeah.c tcp: add helper for AI algorithm 2009-03-02 03:00:15 -08:00
tcp.c ipv4: remove unused parameter from tcp_recv_urg(). 2009-03-31 14:43:17 -07:00
tunnel4.c [IPV4] TUNNEL4: Fix incoming packet length check for inter-protocol tunnel. 2008-06-05 04:02:33 +09:00
udp_impl.h udp: introduce struct udp_table and multiple spinlocks 2008-10-29 01:41:45 -07:00
udp.c ipv6: Fix NULL pointer dereference with time-wait sockets 2009-04-11 01:53:06 -07:00
udplite.c udp: RCU handling for Unicast packets. 2008-10-29 02:11:14 -07:00
xfrm4_input.c ipsec: Remove useless ret variable 2008-12-26 01:31:18 -08:00
xfrm4_mode_beet.c ipsec: Interfamily IPSec BEET 2008-08-06 02:39:30 -07:00
xfrm4_mode_transport.c [IPSEC]: Use IPv6 calling convention as the convention for x->mode->output 2007-10-10 16:55:54 -07:00
xfrm4_mode_tunnel.c xfrm: fix fragmentation for ipv4 xfrm tunnel 2008-06-17 16:38:23 -07:00
xfrm4_output.c [IPSEC]: Fix inter address family IPsec tunnel handling. 2008-03-24 14:51:51 -07:00
xfrm4_policy.c net: replace uses of __constant_{endian} 2009-02-01 00:45:17 -08:00
xfrm4_state.c xfrm: remove useless forward declarations 2008-11-25 01:05:54 -08:00
xfrm4_tunnel.c [IPCOMP]: Fix reception of incompressible packets 2008-01-31 19:27:24 -08:00