linux-sg2042/net/decnet
Eric Dumazet e67f88dd12 net: dont hold rtnl mutex during netlink dump callbacks
Four years ago, Patrick made a change to hold rtnl mutex during netlink
dump callbacks.

I believe it was a wrong move. This slows down concurrent dumps, making
good old /proc/net/ files faster than rtnetlink in some situations.

This occurred to me because one "ip link show dev ..." was _very_ slow
on a workload adding/removing network devices in background.

All dump callbacks are able to use RCU locking now, so this patch does
roughly a revert of commits :

1c2d670f36 : [RTNETLINK]: Hold rtnl_mutex during netlink dump callbacks
6313c1e099 : [RTNETLINK]: Remove unnecessary locking in dump callbacks

This let writers fight for rtnl mutex and readers going full speed.

It also takes care of phonet : phonet_route_get() is now called from rcu
read section. I renamed it to phonet_route_get_rcu()

Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Cc: Patrick McHardy <kaber@trash.net>
Cc: Remi Denis-Courmont <remi.denis-courmont@nokia.com>
Acked-by: Stephen Hemminger <shemminger@vyatta.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2011-05-02 15:26:28 -07:00
..
netfilter include cleanup: Update gfp.h and slab.h includes to prepare for breaking implicit slab.h inclusion from percpu.h 2010-03-30 22:02:32 +09:00
Kconfig [NET]: Rethink mark field in struct flowi 2006-12-02 21:21:39 -08:00
Makefile Linux-2.6.12-rc2 2005-04-16 15:20:36 -07:00
README Linux-2.6.12-rc2 2005-04-16 15:20:36 -07:00
TODO Linux-2.6.12-rc2 2005-04-16 15:20:36 -07:00
af_decnet.c decnet: Convert to use flowidn where applicable. 2011-03-12 15:08:55 -08:00
dn_dev.c net: dont hold rtnl mutex during netlink dump callbacks 2011-05-02 15:26:28 -07:00
dn_fib.c decnet: Convert to use flowidn where applicable. 2011-03-12 15:08:55 -08:00
dn_neigh.c decnet: RCU conversion and get rid of dev_base_lock 2010-11-08 13:50:08 -08:00
dn_nsp_in.c Merge branch 'master' of /repos/git/net-next-2.6 2010-04-20 16:02:01 +02:00
dn_nsp_out.c decnet: Convert to use flowidn where applicable. 2011-03-12 15:08:55 -08:00
dn_route.c net: Use non-zero allocations in dst_alloc(). 2011-04-28 22:26:00 -07:00
dn_rules.c decnet: Convert to use flowidn where applicable. 2011-03-12 15:08:55 -08:00
dn_table.c decnet: Don't leak entries when rebuilding zone. 2011-04-17 20:47:07 -07:00
dn_timer.c Linux-2.6.12-rc2 2005-04-16 15:20:36 -07:00
sysctl_net_decnet.c net: avoid limits overflow 2010-11-10 12:12:00 -08:00

README

                       Linux DECnet Project
                      ======================

The documentation for this kernel subsystem is available in the
Documentation/networking subdirectory of this distribution and also
on line at http://www.chygwyn.com/DECnet/

Steve Whitehouse <SteveW@ACM.org>