[PATCH tip/core/rcu 30/41] netfilter: Replace call_rcu_bh(), rcu_barrier_bh(), and synchronize_rcu_bh()

From: Paul E. McKenney
Date: Sun Nov 11 2018 - 14:44:39 EST


Now that call_rcu()'s callback is not invoked until after bh-disable
regions of code have completed (in addition to explicitly marked
RCU read-side critical sections), call_rcu() can be used in place
of call_rcu_bh(). Similarly, rcu_barrier() can be used in place of
rcu_barrier_bh() and synchronize_rcu() in place of synchronize_rcu_bh().
This commit therefore makes these changes.

Signed-off-by: Paul E. McKenney <paulmck@xxxxxxxxxxxxx>
Cc: Pablo Neira Ayuso <pablo@xxxxxxxxxxxxx>
Cc: Jozsef Kadlecsik <kadlec@xxxxxxxxxxxxxxxxx>
Cc: Florian Westphal <fw@xxxxxxxxx>
Cc: "David S. Miller" <davem@xxxxxxxxxxxxx>
Cc: Alexey Kuznetsov <kuznet@xxxxxxxxxxxxx>
Cc: Hideaki YOSHIFUJI <yoshfuji@xxxxxxxxxxxxxx>
Cc: <netfilter-devel@xxxxxxxxxxxxxxx>
Cc: <coreteam@xxxxxxxxxxxxx>
Cc: <netdev@xxxxxxxxxxxxxxx>
---
net/ipv4/netfilter/ipt_CLUSTERIP.c | 6 +++---
net/netfilter/ipset/ip_set_hash_gen.h | 4 ++--
net/netfilter/nfnetlink_log.c | 2 +-
net/netfilter/xt_hashlimit.c | 4 ++--
4 files changed, 8 insertions(+), 8 deletions(-)

diff --git a/net/ipv4/netfilter/ipt_CLUSTERIP.c b/net/ipv4/netfilter/ipt_CLUSTERIP.c
index 2c8d313ae216..5b0c1ee6ae26 100644
--- a/net/ipv4/netfilter/ipt_CLUSTERIP.c
+++ b/net/ipv4/netfilter/ipt_CLUSTERIP.c
@@ -94,7 +94,7 @@ static inline void
clusterip_config_put(struct clusterip_config *c)
{
if (refcount_dec_and_test(&c->refcount))
- call_rcu_bh(&c->rcu, clusterip_config_rcu_free);
+ call_rcu(&c->rcu, clusterip_config_rcu_free);
}

/* decrease the count of entries using/referencing this config. If last
@@ -876,8 +876,8 @@ static void __exit clusterip_tg_exit(void)
xt_unregister_target(&clusterip_tg_reg);
unregister_pernet_subsys(&clusterip_net_ops);

- /* Wait for completion of call_rcu_bh()'s (clusterip_config_rcu_free) */
- rcu_barrier_bh();
+ /* Wait for completion of call_rcu()'s (clusterip_config_rcu_free) */
+ rcu_barrier();
}

module_init(clusterip_tg_init);
diff --git a/net/netfilter/ipset/ip_set_hash_gen.h b/net/netfilter/ipset/ip_set_hash_gen.h
index e287da68d5fa..2c9609929c71 100644
--- a/net/netfilter/ipset/ip_set_hash_gen.h
+++ b/net/netfilter/ipset/ip_set_hash_gen.h
@@ -67,7 +67,7 @@ tune_ahash_max(u8 curr, u32 multi)

/* A hash bucket */
struct hbucket {
- struct rcu_head rcu; /* for call_rcu_bh */
+ struct rcu_head rcu; /* for call_rcu */
/* Which positions are used in the array */
DECLARE_BITMAP(used, AHASH_MAX_TUNED);
u8 size; /* size of the array */
@@ -664,7 +664,7 @@ mtype_resize(struct ip_set *set, bool retried)
spin_unlock_bh(&set->lock);

/* Give time to other readers of the set */
- synchronize_rcu_bh();
+ synchronize_rcu();

pr_debug("set %s resized from %u (%p) to %u (%p)\n", set->name,
orig->htable_bits, orig, t->htable_bits, t);
diff --git a/net/netfilter/nfnetlink_log.c b/net/netfilter/nfnetlink_log.c
index 332c69d27b47..b1f9c5303f02 100644
--- a/net/netfilter/nfnetlink_log.c
+++ b/net/netfilter/nfnetlink_log.c
@@ -148,7 +148,7 @@ static void
instance_put(struct nfulnl_instance *inst)
{
if (inst && refcount_dec_and_test(&inst->use))
- call_rcu_bh(&inst->rcu, nfulnl_instance_free_rcu);
+ call_rcu(&inst->rcu, nfulnl_instance_free_rcu);
}

static void nfulnl_timer(struct timer_list *t);
diff --git a/net/netfilter/xt_hashlimit.c b/net/netfilter/xt_hashlimit.c
index 3e7d259e5d8d..8138b68a9a44 100644
--- a/net/netfilter/xt_hashlimit.c
+++ b/net/netfilter/xt_hashlimit.c
@@ -260,7 +260,7 @@ static inline void
dsthash_free(struct xt_hashlimit_htable *ht, struct dsthash_ent *ent)
{
hlist_del_rcu(&ent->node);
- call_rcu_bh(&ent->rcu, dsthash_free_rcu);
+ call_rcu(&ent->rcu, dsthash_free_rcu);
ht->count--;
}
static void htable_gc(struct work_struct *work);
@@ -1329,7 +1329,7 @@ static void __exit hashlimit_mt_exit(void)
xt_unregister_matches(hashlimit_mt_reg, ARRAY_SIZE(hashlimit_mt_reg));
unregister_pernet_subsys(&hashlimit_net_ops);

- rcu_barrier_bh();
+ rcu_barrier();
kmem_cache_destroy(hashlimit_cachep);
}

--
2.17.1