tree c0387e21f2af12e91f485ac0c944cefab9359a2a
parent 80055dab5de0c8677bc148c4717ddfc753a9148e
author Florian Westphal <fw@strlen.de> 1507763631 +0200
committer Pablo Neira Ayuso <pablo@netfilter.org> 1508860910 +0200

netfilter: x_tables: don't use seqlock when fetching old counters

after previous commit xt_replace_table will wait until all cpus
had even seqcount (i.e., no cpu is accessing old ruleset).

Add a 'old' counter retrival version that doesn't synchronize counters.
Its not needed, the old counters are not in use anymore at this point.

This speeds up table replacement on busy systems with large tables
(and many cores).

Cc: Dan Williams <dcbw@redhat.com>
Cc: Eric Dumazet <edumazet@google.com>
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>