Donate to e Foundation | Murena handsets with /e/OS | Own a part of Murena! Learn more

Commit 4be2b04e authored by Paul E. McKenney's avatar Paul E. McKenney
Browse files

netfilter: Remove now-redundant smp_read_barrier_depends() 



READ_ONCE() now implies smp_read_barrier_depends(), which means that
the instances in arpt_do_table(), ipt_do_table(), and ip6t_do_table()
are now redundant.  This commit removes them and adjusts the comments.

Signed-off-by: default avatarPaul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Pablo Neira Ayuso <pablo@netfilter.org>
Cc: Jozsef Kadlecsik <kadlec@blackhole.kfki.hu>
Cc: Florian Westphal <fw@strlen.de>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: <netfilter-devel@vger.kernel.org>
Cc: <coreteam@netfilter.org>
Cc: <netdev@vger.kernel.org>
parent 08df4774

net/ipv4/netfilter/arp_tables.c

+1 −6
Original line number Diff line number Diff line
@@ -202,13 +202,8 @@ unsigned int arpt_do_table(struct sk_buff *skb, 


	local_bh_disable();

	addend = xt_write_recseq_begin();

	private = table->private;

	private = READ_ONCE(table->private); /* Address dependency. */

	cpu     = smp_processor_id();

	/*

	 * Ensure we load private-> members after we've fetched the base

	 * pointer.

	 */

	smp_read_barrier_depends();

	table_base = private->entries;

	jumpstack  = (struct arpt_entry **)private->jumpstack[cpu];

net/ipv4/netfilter/ip_tables.c

+1 −6
Original line number Diff line number Diff line
@@ -260,13 +260,8 @@ ipt_do_table(struct sk_buff *skb, 
	WARN_ON(!(table->valid_hooks & (1 << hook)));

	local_bh_disable();

	addend = xt_write_recseq_begin();

	private = table->private;

	private = READ_ONCE(table->private); /* Address dependency. */

	cpu        = smp_processor_id();

	/*

	 * Ensure we load private-> members after we've fetched the base

	 * pointer.

	 */

	smp_read_barrier_depends();

	table_base = private->entries;

	jumpstack  = (struct ipt_entry **)private->jumpstack[cpu];

net/ipv6/netfilter/ip6_tables.c

+1 −6
Original line number Diff line number Diff line
@@ -282,12 +282,7 @@ ip6t_do_table(struct sk_buff *skb, 


	local_bh_disable();

	addend = xt_write_recseq_begin();

	private = table->private;

	/*

	 * Ensure we load private-> members after we've fetched the base

	 * pointer.

	 */

	smp_read_barrier_depends();

	private = READ_ONCE(table->private); /* Address dependency. */

	cpu        = smp_processor_id();

	table_base = private->entries;

	jumpstack  = (struct ip6t_entry **)private->jumpstack[cpu];