Commit 290aa0ad authored by Vlad Buslov's avatar Vlad Buslov Committed by David S. Miller
Browse files

net: sched: don't disable bh when accessing action idr 



Initial net_device implementation used ingress_lock spinlock to synchronize
ingress path of device. This lock was used in both process and bh context.
In some code paths action map lock was obtained while holding ingress_lock.
Commit e1e992e5 ("[NET_SCHED] protect action config/dump from irqs")
modified actions to always disable bh, while using action map lock, in
order to prevent deadlock on ingress_lock in softirq. This lock was removed
from net_device, so disabling bh, while accessing action map, is no longer
necessary.

Replace all action idr spinlock usage with regular calls that do not
disable bh.

Signed-off-by: default avatarVlad Buslov <vladbu@mellanox.com>
Acked-by: default avatarJamal Hadi Salim <jhs@mojatatu.com>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
parent 73bf1fc5

net/sched/act_api.c

+10 −10
Original line number Diff line number Diff line
@@ -77,9 +77,9 @@ static void free_tcf(struct tc_action *p) 


static void tcf_idr_remove(struct tcf_idrinfo *idrinfo, struct tc_action *p)

{

	spin_lock_bh(&idrinfo->lock);

	spin_lock(&idrinfo->lock);

	idr_remove(&idrinfo->action_idr, p->tcfa_index);

	spin_unlock_bh(&idrinfo->lock);

	spin_unlock(&idrinfo->lock);

	gen_kill_estimator(&p->tcfa_rate_est);

	free_tcf(p);

}
@@ -156,7 +156,7 @@ static int tcf_dump_walker(struct tcf_idrinfo *idrinfo, struct sk_buff *skb, 
	struct tc_action *p;

	unsigned long id = 1;



	spin_lock_bh(&idrinfo->lock);

	spin_lock(&idrinfo->lock);



	s_i = cb->args[0];
@@ -191,7 +191,7 @@ done: 
	if (index >= 0)

		cb->args[0] = index + 1;



	spin_unlock_bh(&idrinfo->lock);

	spin_unlock(&idrinfo->lock);

	if (n_i) {

		if (act_flags & TCA_FLAG_LARGE_DUMP_ON)

			cb->args[1] = n_i;
@@ -261,9 +261,9 @@ static struct tc_action *tcf_idr_lookup(u32 index, struct tcf_idrinfo *idrinfo) 
{

	struct tc_action *p = NULL;



	spin_lock_bh(&idrinfo->lock);

	spin_lock(&idrinfo->lock);

	p = idr_find(&idrinfo->action_idr, index);

	spin_unlock_bh(&idrinfo->lock);

	spin_unlock(&idrinfo->lock);



	return p;

}
@@ -323,7 +323,7 @@ int tcf_idr_create(struct tc_action_net *tn, u32 index, struct nlattr *est, 
	}

	spin_lock_init(&p->tcfa_lock);

	idr_preload(GFP_KERNEL);

	spin_lock_bh(&idrinfo->lock);

	spin_lock(&idrinfo->lock);

	/* user doesn't specify an index */

	if (!index) {

		index = 1;
@@ -331,7 +331,7 @@ int tcf_idr_create(struct tc_action_net *tn, u32 index, struct nlattr *est, 
	} else {

		err = idr_alloc_u32(idr, NULL, &index, index, GFP_ATOMIC);

	}

	spin_unlock_bh(&idrinfo->lock);

	spin_unlock(&idrinfo->lock);

	idr_preload_end();

	if (err)

		goto err3;
@@ -369,9 +369,9 @@ void tcf_idr_insert(struct tc_action_net *tn, struct tc_action *a) 
{

	struct tcf_idrinfo *idrinfo = tn->idrinfo;



	spin_lock_bh(&idrinfo->lock);

	spin_lock(&idrinfo->lock);

	idr_replace(&idrinfo->action_idr, a, a->tcfa_index);

	spin_unlock_bh(&idrinfo->lock);

	spin_unlock(&idrinfo->lock);

}

EXPORT_SYMBOL(tcf_idr_insert);

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