pkt_sched: Fix lockdep warning on est_tree_lock in gen_estimator
This patch fixes a lockdep warning:
[ 516.287584] =========================================================
[ 516.288386] [ INFO: possible irq lock inversion dependency detected ]
[ 516.288386] 2.6.35b #7
[ 516.288386] ---------------------------------------------------------
[ 516.288386] swapper/0 just changed the state of lock:
[ 516.288386] (&qdisc_tx_lock){+.-...}, at: [<c12eacda>] est_timer+0x62/0x1b4
[ 516.288386] but this lock took another, SOFTIRQ-unsafe lock in the past:
[ 516.288386] (est_tree_lock){+.+...}
[ 516.288386]
[ 516.288386] and interrupts could create inverse lock ordering between them.
...
So, est_tree_lock needs BH protection because it's taken by
qdisc_tx_lock, which is used both in BH and process contexts.
(Full warning with this patch at netdev, 02 Sep 2010.)
Fixes commit: ae638c47dc040b8def16d05dc6acdd527628f231
("pkt_sched: gen_estimator: add a new lock")
Signed-off-by: Jarek Poplawski <jarkao2@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/core/gen_estimator.c b/net/core/gen_estimator.c
index 9fbe7f7..6743146 100644
--- a/net/core/gen_estimator.c
+++ b/net/core/gen_estimator.c
@@ -232,7 +232,7 @@
est->last_packets = bstats->packets;
est->avpps = rate_est->pps<<10;
- spin_lock(&est_tree_lock);
+ spin_lock_bh(&est_tree_lock);
if (!elist[idx].timer.function) {
INIT_LIST_HEAD(&elist[idx].list);
setup_timer(&elist[idx].timer, est_timer, idx);
@@ -243,7 +243,7 @@
list_add_rcu(&est->list, &elist[idx].list);
gen_add_node(est);
- spin_unlock(&est_tree_lock);
+ spin_unlock_bh(&est_tree_lock);
return 0;
}
@@ -270,7 +270,7 @@
{
struct gen_estimator *e;
- spin_lock(&est_tree_lock);
+ spin_lock_bh(&est_tree_lock);
while ((e = gen_find_node(bstats, rate_est))) {
rb_erase(&e->node, &est_root);
@@ -281,7 +281,7 @@
list_del_rcu(&e->list);
call_rcu(&e->e_rcu, __gen_kill_estimator);
}
- spin_unlock(&est_tree_lock);
+ spin_unlock_bh(&est_tree_lock);
}
EXPORT_SYMBOL(gen_kill_estimator);
@@ -320,9 +320,9 @@
ASSERT_RTNL();
- spin_lock(&est_tree_lock);
+ spin_lock_bh(&est_tree_lock);
res = gen_find_node(bstats, rate_est) != NULL;
- spin_unlock(&est_tree_lock);
+ spin_unlock_bh(&est_tree_lock);
return res;
}