Andi Kleen 6eac560407 tcp: Skip empty hash buckets faster in /proc/net/tcp ... On most systems most of the TCP established/time-wait hash buckets are empty. When walking the hash table for /proc/net/tcp their read locks would always be aquired just to find out they're empty. This patch changes the code to check first if the buckets have any entries before taking the lock, which is much cheaper than taking a lock. Since the hash tables are large this makes a measurable difference on processing /proc/net/tcp, especially on architectures with slow read_lock (e.g. PPC) On a 2GB Core2 system time cat /proc/net/tcp > /dev/null (with a mostly empty hash table) goes from 0.046s to 0.005s. On systems with slower atomics (like P4 or POWER4) or larger hash tables (more RAM) the difference is much higher. This can be noticeable because there are some daemons around who regularly scan /proc/net/tcp. Original idea for this patch from Marcus Meissner, but redone by me. Signed-off-by: Andi Kleen <ak@suse.de> Signed-off-by: David S. Miller <davem@davemloft.net>		2008-08-28 01:08:02 -07:00
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9p	flag parameters: socket and socketpair	2008-07-24 10:47:27 -07:00
802	list_for_each_rcu must die: networking	2008-07-25 10:53:27 -07:00
8021q	netdev: Handle ->addr_list_lock just like ->_xmit_lock for lockdep.	2008-07-22 14:16:42 -07:00
appletalk	net: convert BUG_TRAP to generic WARN_ON	2008-07-25 21:43:18 -07:00
atm	atm: fix const assignment/discard warnings in the ATM networking driver	2008-07-30 16:31:46 -07:00
ax25	AX.25: Fix sysctl registration if !CONFIG_AX25_DAMA_SLAVE	2008-08-05 18:46:57 -07:00
bluetooth	[Bluetooth] Consolidate maintainers information	2008-08-18 13:23:53 +02:00
bridge	bridge: show offload settings	2008-08-15 19:51:07 -07:00
can	netns: Use net_eq() to compare net-namespaces for optimization.	2008-07-19 22:34:43 -07:00
core	pkt_sched: Prevent livelock in TX queue running.	2008-08-19 04:00:36 -07:00
dccp	dccp ccid-3: Replace lazy BUG_ON with condition	2008-08-27 07:22:00 +02:00
decnet	netns: Use net_eq() to compare net-namespaces for optimization.	2008-07-19 22:34:43 -07:00
econet	netns: Use net_eq() to compare net-namespaces for optimization.	2008-07-19 22:34:43 -07:00
ethernet	[NET]: Return more appropriate error from eth_validate_addr().	2008-04-13 22:45:40 -07:00
ieee80211	net/ieee80211: adjust error handling	2008-08-22 16:29:49 -04:00
ipv4	tcp: Skip empty hash buckets faster in /proc/net/tcp	2008-08-28 01:08:02 -07:00
ipv6	ipv6: Fix the return interface index when get it while no message is received.	2008-08-17 23:21:52 -07:00
ipx	netns: Use net_eq() to compare net-namespaces for optimization.	2008-07-19 22:34:43 -07:00
irda	Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-2.6	2008-07-20 17:43:29 -07:00
iucv	Merge branch 'linus' into cpus4096-for-linus	2008-07-21 17:19:50 +02:00
key	net: convert BUG_TRAP to generic WARN_ON	2008-07-25 21:43:18 -07:00
lapb	[LAPB] net/lapb/lapb_iface.c: use LIST_HEAD instead of LIST_HEAD_INIT	2008-01-28 14:56:52 -08:00
llc	netns: Use net_eq() to compare net-namespaces for optimization.	2008-07-19 22:34:43 -07:00
mac80211	mac80211: add direct probe before association	2008-08-22 16:30:00 -04:00
netfilter	netfilter: ctnetlink: sleepable allocation with spin lock bh	2008-08-18 21:31:46 -07:00
netlabel	netns: Use net_eq() to compare net-namespaces for optimization.	2008-07-19 22:34:43 -07:00
netlink	net: convert BUG_TRAP to generic WARN_ON	2008-07-25 21:43:18 -07:00
netrom	netdev: Handle ->addr_list_lock just like ->_xmit_lock for lockdep.	2008-07-22 14:16:42 -07:00
packet	net: convert BUG_TRAP to generic WARN_ON	2008-07-25 21:43:18 -07:00
rfkill	rfkill: introduce RFKILL_STATE_MAX	2008-08-22 16:29:57 -04:00
rose	netdev: Handle ->addr_list_lock just like ->_xmit_lock for lockdep.	2008-07-22 14:16:42 -07:00
rxrpc	net/rxrpc: Use an IS_ERR test rather than a NULL test	2008-08-13 02:40:48 -07:00
sched	pkt_sched: Fix qdisc_watchdog() vs. dev_deactivate() race	2008-08-21 05:11:14 -07:00
sctp	sctp: fix potential panics in the SCTP-AUTH API.	2008-08-21 03:34:25 -07:00
sunrpc	Merge branch 'linus' into cpus4096	2008-07-28 21:14:43 +02:00
tipc	net/tipc/subscr.c: don't use ___constant_swab32	2008-08-13 02:32:06 -07:00
unix	Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs-2.6	2008-07-26 20:23:44 -07:00
wanrouter	wanmain.c doesn't need syncppp.h	2008-07-23 23:00:36 +02:00
wireless	wext: Send name on events	2008-08-13 02:39:56 -07:00
x25	netns: Use net_eq() to compare net-namespaces for optimization.	2008-07-19 22:34:43 -07:00
xfrm	xfrm: remove unnecessary variable in xfrm_output_resume() 2nd try	2008-08-13 13:35:37 -07:00
compat.c	flag parameters: paccept	2008-07-24 10:47:27 -07:00
Kconfig	WIRELESS: Make wireless one-click selectable.	2008-08-22 16:29:50 -04:00
Makefile	vlan: uninline __vlan_hwaccel_rx	2008-07-08 03:23:36 -07:00
nonet.c
socket.c	SL*B: drop kmem cache argument from constructor	2008-07-26 12:00:07 -07:00
sysctl_net.c	missing bits of net-namespace / sysctl	2008-07-27 09:45:34 -07:00
TUNABLE