linux-sg2042/net/dccp
Eric Dumazet 230140cffa [INET]: Remove per bucket rwlock in tcp/dccp ehash table.
As done two years ago on IP route cache table (commit
22c047ccbc) , we can avoid using one
lock per hash bucket for the huge TCP/DCCP hash tables.

On a typical x86_64 platform, this saves about 2MB or 4MB of ram, for
litle performance differences. (we hit a different cache line for the
rwlock, but then the bucket cache line have a better sharing factor
among cpus, since we dirty it less often). For netstat or ss commands
that want a full scan of hash table, we perform fewer memory accesses.

Using a 'small' table of hashed rwlocks should be more than enough to
provide correct SMP concurrency between different buckets, without
using too much memory. Sizing of this table depends on
num_possible_cpus() and various CONFIG settings.

This patch provides some locking abstraction that may ease a future
work using a different model for TCP/DCCP table.

Signed-off-by: Eric Dumazet <dada1@cosmosbay.com>
Acked-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2007-11-07 04:15:11 -08:00
..
ccids [CCID2/3]: Initialisation assignments of 0 are redundant 2007-10-24 10:53:01 -02:00
Kconfig [DCCP]: Use menuconfig objects. 2007-05-24 16:36:46 -07:00
Makefile [DCCPv6]: Resolve conditional build problem 2006-12-02 21:22:28 -08:00
ackvec.c [NET]: DIV_ROUND_UP cleanup (part two) 2007-10-10 16:48:37 -07:00
ackvec.h [DCCP] ackvec: Convert to ktime_t 2007-10-10 16:48:14 -07:00
ccid.c [DCCP]: fix theoretical ccids_{read,write}_lock() race 2007-08-13 22:52:09 -07:00
ccid.h [DCCP] ccid: Deprecate ccid_hc_tx_insert_options 2006-12-11 14:34:49 -08:00
dccp.h [DCCP]: Factor out common code for generating Resets 2007-10-10 16:52:44 -07:00
diag.c [INET]: Let inet_diag and friends autoload 2007-10-22 02:59:54 -07:00
feat.c [DCCP]: fix memory leak and clean up style - dccp_feat_empty_confirm() 2007-08-13 22:52:10 -07:00
feat.h [NET] DCCP: Fix whitespace errors. 2007-02-10 23:19:27 -08:00
input.c [DCCP]: Convert Reset code into socket error number 2007-10-24 10:27:48 -02:00
ipv4.c [DCCP]: Use DEFINE_PROTO_INUSE infrastructure. 2007-11-07 04:09:01 -08:00
ipv6.c [DCCP]: Use DEFINE_PROTO_INUSE infrastructure. 2007-11-07 04:09:01 -08:00
ipv6.h Remove obsolete #include <linux/config.h> 2006-06-30 19:25:36 +02:00
minisocks.c [DCCP]: Tidy-up -- minisock initialisation 2007-10-10 16:54:36 -07:00
options.c [DCCP]: Unaligned pointer access 2007-10-24 10:46:58 -02:00
output.c [DCCP]: Wait for CCID 2007-10-10 16:54:31 -07:00
probe.c [NET]: Make /proc/net per network namespace 2007-10-10 16:49:06 -07:00
proto.c [INET]: Remove per bucket rwlock in tcp/dccp ehash table. 2007-11-07 04:15:11 -08:00
sysctl.c [DCCP]: fix link error with !CONFIG_SYSCTL 2007-10-17 19:33:06 -07:00
timer.c [DCCP]: Provide 10s of microsecond timesource 2007-10-10 16:52:35 -07:00