From ae638c47dc040b8def16d05dc6acdd527628f231 Mon Sep 17 00:00:00 2001 From: Eric Dumazet Date: Tue, 8 Jun 2010 23:39:10 +0000 Subject: [PATCH] pkt_sched: gen_estimator: add a new lock gen_kill_estimator() / gen_new_estimator() is not always called with RTNL held. net/netfilter/xt_RATEEST.c is one user of these API that do not hold RTNL, so random corruptions can occur between "tc" and "iptables". Add a new fine grained lock instead of trying to use RTNL in netfilter. Signed-off-by: Eric Dumazet Signed-off-by: David S. Miller --- net/core/gen_estimator.c | 15 ++++++++++++--- 1 file changed, 12 insertions(+), 3 deletions(-) diff --git a/net/core/gen_estimator.c b/net/core/gen_estimator.c index cf8e70392fe0..785e5276a300 100644 --- a/net/core/gen_estimator.c +++ b/net/core/gen_estimator.c @@ -107,6 +107,7 @@ static DEFINE_RWLOCK(est_lock); /* Protects against soft lockup during large deletion */ static struct rb_root est_root = RB_ROOT; +static DEFINE_SPINLOCK(est_tree_lock); static void est_timer(unsigned long arg) { @@ -201,7 +202,6 @@ struct gen_estimator *gen_find_node(const struct gnet_stats_basic_packed *bstats * * Returns 0 on success or a negative error code. * - * NOTE: Called under rtnl_mutex */ int gen_new_estimator(struct gnet_stats_basic_packed *bstats, struct gnet_stats_rate_est *rate_est, @@ -232,6 +232,7 @@ int gen_new_estimator(struct gnet_stats_basic_packed *bstats, est->last_packets = bstats->packets; est->avpps = rate_est->pps<<10; + spin_lock(&est_tree_lock); if (!elist[idx].timer.function) { INIT_LIST_HEAD(&elist[idx].list); setup_timer(&elist[idx].timer, est_timer, idx); @@ -242,6 +243,7 @@ int gen_new_estimator(struct gnet_stats_basic_packed *bstats, list_add_rcu(&est->list, &elist[idx].list); gen_add_node(est); + spin_unlock(&est_tree_lock); return 0; } @@ -261,13 +263,13 @@ static void __gen_kill_estimator(struct rcu_head *head) * * Removes the rate estimator specified by &bstats and &rate_est. * - * NOTE: Called under rtnl_mutex */ void gen_kill_estimator(struct gnet_stats_basic_packed *bstats, struct gnet_stats_rate_est *rate_est) { struct gen_estimator *e; + spin_lock(&est_tree_lock); while ((e = gen_find_node(bstats, rate_est))) { rb_erase(&e->node, &est_root); @@ -278,6 +280,7 @@ void gen_kill_estimator(struct gnet_stats_basic_packed *bstats, list_del_rcu(&e->list); call_rcu(&e->e_rcu, __gen_kill_estimator); } + spin_unlock(&est_tree_lock); } EXPORT_SYMBOL(gen_kill_estimator); @@ -312,8 +315,14 @@ EXPORT_SYMBOL(gen_replace_estimator); bool gen_estimator_active(const struct gnet_stats_basic_packed *bstats, const struct gnet_stats_rate_est *rate_est) { + bool res; + ASSERT_RTNL(); - return gen_find_node(bstats, rate_est) != NULL; + spin_lock(&est_tree_lock); + res = gen_find_node(bstats, rate_est) != NULL; + spin_unlock(&est_tree_lock); + + return res; } EXPORT_SYMBOL(gen_estimator_active);