diff mbox series

[net-next,02/15] net: fib_notifier: make FIB notifier per-netns

Message ID 20190914064608.26799-3-jiri@resnulli.us
State Changes Requested
Delegated to: David Miller
Headers show
Series devlink: allow devlink instances to change network namespace | expand

Commit Message

Jiri Pirko Sept. 14, 2019, 6:45 a.m. UTC 
From: Jiri Pirko <jiri@mellanox.com>

Currently all users of FIB notifier only cares about events in init_net.
Later in this patchset, users get interested in other namespaces too.
However, for every registered block user is interested only about one
namespace. Make the FIB notifier registration per-netns and avoid
unnecessary calls of notifier block for other namespaces.

Signed-off-by: Jiri Pirko <jiri@mellanox.com>
---
 .../net/ethernet/mellanox/mlx5/core/lag_mp.c  |  7 +-
 .../ethernet/mellanox/mlxsw/spectrum_router.c |  7 +-
 drivers/net/ethernet/rocker/rocker_main.c     |  9 +-
 drivers/net/netdevsim/fib.c                   |  8 +-
 include/linux/mroute_base.h                   |  8 +-
 include/net/fib_notifier.h                    |  6 +-
 include/net/ip6_fib.h                         |  2 +-
 include/net/ip_fib.h                          |  2 +-
 net/core/fib_notifier.c                       | 85 +++++++++----------
 net/core/fib_rules.c                          |  7 +-
 net/ipv4/fib_notifier.c                       |  4 +-
 net/ipv4/fib_trie.c                           | 17 ++--
 net/ipv4/ipmr_base.c                          |  4 +-
 net/ipv6/fib6_notifier.c                      |  4 +-
 net/ipv6/ip6_fib.c                            |  6 +-
 15 files changed, 77 insertions(+), 99 deletions(-)

Comments

Ido Schimmel Sept. 15, 2019, 8:06 a.m. UTC | #1 
On Sat, Sep 14, 2019 at 08:45:55AM +0200, Jiri Pirko wrote:
> From: Jiri Pirko <jiri@mellanox.com>
> 
> Currently all users of FIB notifier only cares about events in init_net.

s/cares/care/

> Later in this patchset, users get interested in other namespaces too.
> However, for every registered block user is interested only about one
> namespace. Make the FIB notifier registration per-netns and avoid
> unnecessary calls of notifier block for other namespaces.

...

> diff --git a/drivers/net/ethernet/mellanox/mlx5/core/lag_mp.c b/drivers/net/ethernet/mellanox/mlx5/core/lag_mp.c
> index 5d20d615663e..fe0cc969cf94 100644
> --- a/drivers/net/ethernet/mellanox/mlx5/core/lag_mp.c
> +++ b/drivers/net/ethernet/mellanox/mlx5/core/lag_mp.c
> @@ -248,9 +248,6 @@ static int mlx5_lag_fib_event(struct notifier_block *nb,
>  	struct net_device *fib_dev;
>  	struct fib_info *fi;
>  
> -	if (!net_eq(info->net, &init_net))
> -		return NOTIFY_DONE;

I don't see anymore uses of 'info->net'. Can it be removed from 'struct
fib_notifier_info' ?
Jiri Pirko Sept. 15, 2019, 9:37 a.m. UTC | #2 
Sun, Sep 15, 2019 at 10:06:02AM CEST, idosch@idosch.org wrote:
>On Sat, Sep 14, 2019 at 08:45:55AM +0200, Jiri Pirko wrote:
>> From: Jiri Pirko <jiri@mellanox.com>
>> 
>> Currently all users of FIB notifier only cares about events in init_net.
>
>s/cares/care/

ok


>
>> Later in this patchset, users get interested in other namespaces too.
>> However, for every registered block user is interested only about one
>> namespace. Make the FIB notifier registration per-netns and avoid
>> unnecessary calls of notifier block for other namespaces.
>
>...
>
>> diff --git a/drivers/net/ethernet/mellanox/mlx5/core/lag_mp.c b/drivers/net/ethernet/mellanox/mlx5/core/lag_mp.c
>> index 5d20d615663e..fe0cc969cf94 100644
>> --- a/drivers/net/ethernet/mellanox/mlx5/core/lag_mp.c
>> +++ b/drivers/net/ethernet/mellanox/mlx5/core/lag_mp.c
>> @@ -248,9 +248,6 @@ static int mlx5_lag_fib_event(struct notifier_block *nb,
>>  	struct net_device *fib_dev;
>>  	struct fib_info *fi;
>>  
>> -	if (!net_eq(info->net, &init_net))
>> -		return NOTIFY_DONE;
>
>I don't see anymore uses of 'info->net'. Can it be removed from 'struct
>fib_notifier_info' ?

correct. I missed that.
David Ahern Sept. 15, 2019, 8:05 p.m. UTC | #3 
On 9/14/19 12:45 AM, Jiri Pirko wrote:
>  #define FIB_DUMP_MAX_RETRIES 5
> -int register_fib_notifier(struct notifier_block *nb,
> +int register_fib_notifier(struct net *net, struct notifier_block *nb,
>  			  void (*cb)(struct notifier_block *nb))
>  {
>  	int retries = 0;
>  	int err;
>  
>  	do {
> -		unsigned int fib_seq = fib_seq_sum();
> -		struct net *net;
> -
> -		rcu_read_lock();
> -		for_each_net_rcu(net) {
> -			err = fib_net_dump(net, nb);
> -			if (err)
> -				goto err_fib_net_dump;
> -		}
> -		rcu_read_unlock();
> -
> -		if (fib_dump_is_consistent(nb, cb, fib_seq))
> +		unsigned int fib_seq = fib_seq_sum(net);
> +
> +		err = fib_net_dump(net, nb);
> +		if (err)
> +			return err;
> +
> +		if (fib_dump_is_consistent(net, nb, cb, fib_seq))
>  			return 0;
>  	} while (++retries < FIB_DUMP_MAX_RETRIES);

This is still more complicated than it needs to be. Why lump all
fib_notifier_ops into 1 dump when they are separate databases with
separate seq numbers? Just dump them 1 at a time and retry that 1
database as needed.

ie., This:
    list_for_each_entry_rcu(ops, &net->fib_notifier_ops, list) {
should be in register_fib_notifier and not fib_net_dump.

as it stands you are potentially replaying way more than is needed when
a dump is inconsistent.


>  
>  	return -EBUSY;
> -
> -err_fib_net_dump:
> -	rcu_read_unlock();
> -	return err;
>  }
>  EXPORT_SYMBOL(register_fib_notifier);
>  
> -int unregister_fib_notifier(struct notifier_block *nb)
> +int unregister_fib_notifier(struct net *net, struct notifier_block *nb)
>  {
> -	return atomic_notifier_chain_unregister(&fib_chain, nb);
> +	struct fib_notifier_net *fn_net = net_generic(net, fib_notifier_net_id);
> +
> +	return atomic_notifier_chain_unregister(&fn_net->fib_chain, nb);
>  }
>  EXPORT_SYMBOL(unregister_fib_notifier);
>
Jiri Pirko Sept. 16, 2019, 5:38 a.m. UTC | #4 
Sun, Sep 15, 2019 at 10:05:47PM CEST, dsahern@gmail.com wrote:
>On 9/14/19 12:45 AM, Jiri Pirko wrote:
>>  #define FIB_DUMP_MAX_RETRIES 5
>> -int register_fib_notifier(struct notifier_block *nb,
>> +int register_fib_notifier(struct net *net, struct notifier_block *nb,
>>  			  void (*cb)(struct notifier_block *nb))
>>  {
>>  	int retries = 0;
>>  	int err;
>>  
>>  	do {
>> -		unsigned int fib_seq = fib_seq_sum();
>> -		struct net *net;
>> -
>> -		rcu_read_lock();
>> -		for_each_net_rcu(net) {
>> -			err = fib_net_dump(net, nb);
>> -			if (err)
>> -				goto err_fib_net_dump;
>> -		}
>> -		rcu_read_unlock();
>> -
>> -		if (fib_dump_is_consistent(nb, cb, fib_seq))
>> +		unsigned int fib_seq = fib_seq_sum(net);
>> +
>> +		err = fib_net_dump(net, nb);
>> +		if (err)
>> +			return err;
>> +
>> +		if (fib_dump_is_consistent(net, nb, cb, fib_seq))
>>  			return 0;
>>  	} while (++retries < FIB_DUMP_MAX_RETRIES);
>
>This is still more complicated than it needs to be. Why lump all
>fib_notifier_ops into 1 dump when they are separate databases with
>separate seq numbers? Just dump them 1 at a time and retry that 1
>database as needed.

Well I think that what you describe is out of scope of this patch. It is
another optimization of fib_notifier. The aim of this patchset is not
optimization of fib_notifier, but devlink netns change. This patchset is
just a dependency.

Can't we do optimization in another patchset? I already struggled to
keep this one within 15-patch limit.

Thanks

>
>ie., This:
>    list_for_each_entry_rcu(ops, &net->fib_notifier_ops, list) {
>should be in register_fib_notifier and not fib_net_dump.
>
>as it stands you are potentially replaying way more than is needed when
>a dump is inconsistent.
>
>
>>  
>>  	return -EBUSY;
>> -
>> -err_fib_net_dump:
>> -	rcu_read_unlock();
>> -	return err;
>>  }
>>  EXPORT_SYMBOL(register_fib_notifier);
>>  
>> -int unregister_fib_notifier(struct notifier_block *nb)
>> +int unregister_fib_notifier(struct net *net, struct notifier_block *nb)
>>  {
>> -	return atomic_notifier_chain_unregister(&fib_chain, nb);
>> +	struct fib_notifier_net *fn_net = net_generic(net, fib_notifier_net_id);
>> +
>> +	return atomic_notifier_chain_unregister(&fn_net->fib_chain, nb);
>>  }
>>  EXPORT_SYMBOL(unregister_fib_notifier);
>>  
>
>
>
>
>
David Ahern Sept. 16, 2019, 2:54 p.m. UTC | #5 
On 9/15/19 11:38 PM, Jiri Pirko wrote:
>> This is still more complicated than it needs to be. Why lump all
>> fib_notifier_ops into 1 dump when they are separate databases with
>> separate seq numbers? Just dump them 1 at a time and retry that 1
>> database as needed.
> 
> Well I think that what you describe is out of scope of this patch. It is
> another optimization of fib_notifier. The aim of this patchset is not
> optimization of fib_notifier, but devlink netns change. This patchset is
> just a dependency.
> 
> Can't we do optimization in another patchset? I already struggled to
> keep this one within 15-patch limit.
> 

sure, but it seems to me it is less work to churn this code all at once
and you are already doing the testing. The fib notifier changes can
always be done as a prep set.
diff mbox series

Patch

diff --git a/drivers/net/ethernet/mellanox/mlx5/core/lag_mp.c b/drivers/net/ethernet/mellanox/mlx5/core/lag_mp.c
index 5d20d615663e..fe0cc969cf94 100644
--- a/drivers/net/ethernet/mellanox/mlx5/core/lag_mp.c
+++ b/drivers/net/ethernet/mellanox/mlx5/core/lag_mp.c
@@ -248,9 +248,6 @@  static int mlx5_lag_fib_event(struct notifier_block *nb,
 	struct net_device *fib_dev;
 	struct fib_info *fi;
 
-	if (!net_eq(info->net, &init_net))
-		return NOTIFY_DONE;
-
 	if (info->family != AF_INET)
 		return NOTIFY_DONE;
 
@@ -311,7 +308,7 @@  int mlx5_lag_mp_init(struct mlx5_lag *ldev)
 		return 0;
 
 	mp->fib_nb.notifier_call = mlx5_lag_fib_event;
-	err = register_fib_notifier(&mp->fib_nb,
+	err = register_fib_notifier(&init_net, &mp->fib_nb,
 				    mlx5_lag_fib_event_flush);
 	if (err)
 		mp->fib_nb.notifier_call = NULL;
@@ -326,6 +323,6 @@  void mlx5_lag_mp_cleanup(struct mlx5_lag *ldev)
 	if (!mp->fib_nb.notifier_call)
 		return;
 
-	unregister_fib_notifier(&mp->fib_nb);
+	unregister_fib_notifier(&init_net, &mp->fib_nb);
 	mp->fib_nb.notifier_call = NULL;
 }
diff --git a/drivers/net/ethernet/mellanox/mlxsw/spectrum_router.c b/drivers/net/ethernet/mellanox/mlxsw/spectrum_router.c
index a330b369e899..6d78d2002335 100644
--- a/drivers/net/ethernet/mellanox/mlxsw/spectrum_router.c
+++ b/drivers/net/ethernet/mellanox/mlxsw/spectrum_router.c
@@ -6250,8 +6250,7 @@  static int mlxsw_sp_router_fib_event(struct notifier_block *nb,
 	struct mlxsw_sp_router *router;
 	int err;
 
-	if (!net_eq(info->net, &init_net) ||
-	    (info->family != AF_INET && info->family != AF_INET6 &&
+	if ((info->family != AF_INET && info->family != AF_INET6 &&
 	     info->family != RTNL_FAMILY_IPMR &&
 	     info->family != RTNL_FAMILY_IP6MR))
 		return NOTIFY_DONE;
@@ -8155,7 +8154,7 @@  int mlxsw_sp_router_init(struct mlxsw_sp *mlxsw_sp)
 		goto err_dscp_init;
 
 	mlxsw_sp->router->fib_nb.notifier_call = mlxsw_sp_router_fib_event;
-	err = register_fib_notifier(&mlxsw_sp->router->fib_nb,
+	err = register_fib_notifier(&init_net, &mlxsw_sp->router->fib_nb,
 				    mlxsw_sp_router_fib_dump_flush);
 	if (err)
 		goto err_register_fib_notifier;
@@ -8195,7 +8194,7 @@  int mlxsw_sp_router_init(struct mlxsw_sp *mlxsw_sp)
 
 void mlxsw_sp_router_fini(struct mlxsw_sp *mlxsw_sp)
 {
-	unregister_fib_notifier(&mlxsw_sp->router->fib_nb);
+	unregister_fib_notifier(&init_net, &mlxsw_sp->router->fib_nb);
 	unregister_netevent_notifier(&mlxsw_sp->router->netevent_nb);
 	mlxsw_sp_neigh_fini(mlxsw_sp);
 	mlxsw_sp_vrs_fini(mlxsw_sp);
diff --git a/drivers/net/ethernet/rocker/rocker_main.c b/drivers/net/ethernet/rocker/rocker_main.c
index 786b158bd305..e54f6341a785 100644
--- a/drivers/net/ethernet/rocker/rocker_main.c
+++ b/drivers/net/ethernet/rocker/rocker_main.c
@@ -2189,9 +2189,6 @@  static int rocker_router_fib_event(struct notifier_block *nb,
 	struct rocker_fib_event_work *fib_work;
 	struct fib_notifier_info *info = ptr;
 
-	if (!net_eq(info->net, &init_net))
-		return NOTIFY_DONE;
-
 	if (info->family != AF_INET)
 		return NOTIFY_DONE;
 
@@ -2994,7 +2991,7 @@  static int rocker_probe(struct pci_dev *pdev, const struct pci_device_id *id)
 	 * the device, so no need to pass a callback.
 	 */
 	rocker->fib_nb.notifier_call = rocker_router_fib_event;
-	err = register_fib_notifier(&rocker->fib_nb, NULL);
+	err = register_fib_notifier(&init_net, &rocker->fib_nb, NULL);
 	if (err)
 		goto err_register_fib_notifier;
 
@@ -3021,7 +3018,7 @@  static int rocker_probe(struct pci_dev *pdev, const struct pci_device_id *id)
 err_register_switchdev_blocking_notifier:
 	unregister_switchdev_notifier(&rocker_switchdev_notifier);
 err_register_switchdev_notifier:
-	unregister_fib_notifier(&rocker->fib_nb);
+	unregister_fib_notifier(&init_net, &rocker->fib_nb);
 err_register_fib_notifier:
 	rocker_remove_ports(rocker);
 err_probe_ports:
@@ -3057,7 +3054,7 @@  static void rocker_remove(struct pci_dev *pdev)
 	unregister_switchdev_blocking_notifier(nb);
 
 	unregister_switchdev_notifier(&rocker_switchdev_notifier);
-	unregister_fib_notifier(&rocker->fib_nb);
+	unregister_fib_notifier(&init_net, &rocker->fib_nb);
 	rocker_remove_ports(rocker);
 	rocker_write32(rocker, CONTROL, ROCKER_CONTROL_RESET);
 	destroy_workqueue(rocker->rocker_owq);
diff --git a/drivers/net/netdevsim/fib.c b/drivers/net/netdevsim/fib.c
index 7de17e42d77a..01ee9cc54605 100644
--- a/drivers/net/netdevsim/fib.c
+++ b/drivers/net/netdevsim/fib.c
@@ -182,9 +182,6 @@  static int nsim_fib_event_nb(struct notifier_block *nb, unsigned long event,
 	struct fib_notifier_info *info = ptr;
 	int err = 0;
 
-	if (!net_eq(info->net, &init_net))
-		return NOTIFY_DONE;
-
 	switch (event) {
 	case FIB_EVENT_RULE_ADD: /* fall through */
 	case FIB_EVENT_RULE_DEL:
@@ -258,7 +255,8 @@  struct nsim_fib_data *nsim_fib_create(struct devlink *devlink)
 	data->ipv6.rules.max = (u64)-1;
 
 	data->fib_nb.notifier_call = nsim_fib_event_nb;
-	err = register_fib_notifier(&data->fib_nb, nsim_fib_dump_inconsistent);
+	err = register_fib_notifier(&init_net, &data->fib_nb,
+				    nsim_fib_dump_inconsistent);
 	if (err) {
 		pr_err("Failed to register fib notifier\n");
 		goto err_out;
@@ -297,6 +295,6 @@  void nsim_fib_destroy(struct devlink *devlink, struct nsim_fib_data *data)
 					    NSIM_RESOURCE_IPV4_FIB_RULES);
 	devlink_resource_occ_get_unregister(devlink,
 					    NSIM_RESOURCE_IPV4_FIB);
-	unregister_fib_notifier(&data->fib_nb);
+	unregister_fib_notifier(&init_net, &data->fib_nb);
 	kfree(data);
 }
diff --git a/include/linux/mroute_base.h b/include/linux/mroute_base.h
index 34de06b426ef..d68c2cd014c3 100644
--- a/include/linux/mroute_base.h
+++ b/include/linux/mroute_base.h
@@ -47,7 +47,6 @@  struct vif_entry_notifier_info {
 };
 
 static inline int mr_call_vif_notifier(struct notifier_block *nb,
-				       struct net *net,
 				       unsigned short family,
 				       enum fib_event_type event_type,
 				       struct vif_device *vif,
@@ -56,7 +55,6 @@  static inline int mr_call_vif_notifier(struct notifier_block *nb,
 	struct vif_entry_notifier_info info = {
 		.info = {
 			.family = family,
-			.net = net,
 		},
 		.dev = vif->dev,
 		.vif_index = vif_index,
@@ -64,7 +62,7 @@  static inline int mr_call_vif_notifier(struct notifier_block *nb,
 		.tb_id = tb_id,
 	};
 
-	return call_fib_notifier(nb, net, event_type, &info.info);
+	return call_fib_notifier(nb, event_type, &info.info);
 }
 
 static inline int mr_call_vif_notifiers(struct net *net,
@@ -173,7 +171,6 @@  struct mfc_entry_notifier_info {
 };
 
 static inline int mr_call_mfc_notifier(struct notifier_block *nb,
-				       struct net *net,
 				       unsigned short family,
 				       enum fib_event_type event_type,
 				       struct mr_mfc *mfc, u32 tb_id)
@@ -181,13 +178,12 @@  static inline int mr_call_mfc_notifier(struct notifier_block *nb,
 	struct mfc_entry_notifier_info info = {
 		.info = {
 			.family = family,
-			.net = net,
 		},
 		.mfc = mfc,
 		.tb_id = tb_id
 	};
 
-	return call_fib_notifier(nb, net, event_type, &info.info);
+	return call_fib_notifier(nb, event_type, &info.info);
 }
 
 static inline int mr_call_mfc_notifiers(struct net *net,
diff --git a/include/net/fib_notifier.h b/include/net/fib_notifier.h
index c49d7bfb5c30..54bb8565efc3 100644
--- a/include/net/fib_notifier.h
+++ b/include/net/fib_notifier.h
@@ -35,14 +35,14 @@  struct fib_notifier_ops {
 	struct rcu_head rcu;
 };
 
-int call_fib_notifier(struct notifier_block *nb, struct net *net,
+int call_fib_notifier(struct notifier_block *nb,
 		      enum fib_event_type event_type,
 		      struct fib_notifier_info *info);
 int call_fib_notifiers(struct net *net, enum fib_event_type event_type,
 		       struct fib_notifier_info *info);
-int register_fib_notifier(struct notifier_block *nb,
+int register_fib_notifier(struct net *net, struct notifier_block *nb,
 			  void (*cb)(struct notifier_block *nb));
-int unregister_fib_notifier(struct notifier_block *nb);
+int unregister_fib_notifier(struct net *net, struct notifier_block *nb);
 struct fib_notifier_ops *
 fib_notifier_ops_register(const struct fib_notifier_ops *tmpl, struct net *net);
 void fib_notifier_ops_unregister(struct fib_notifier_ops *ops);
diff --git a/include/net/ip6_fib.h b/include/net/ip6_fib.h
index 4b5656c71abc..14e9fca0e326 100644
--- a/include/net/ip6_fib.h
+++ b/include/net/ip6_fib.h
@@ -478,7 +478,7 @@  struct ipv6_route_iter {
 
 extern const struct seq_operations ipv6_route_seq_ops;
 
-int call_fib6_notifier(struct notifier_block *nb, struct net *net,
+int call_fib6_notifier(struct notifier_block *nb,
 		       enum fib_event_type event_type,
 		       struct fib_notifier_info *info);
 int call_fib6_notifiers(struct net *net, enum fib_event_type event_type,
diff --git a/include/net/ip_fib.h b/include/net/ip_fib.h
index 4c81846ccce8..4cec9ecaa95e 100644
--- a/include/net/ip_fib.h
+++ b/include/net/ip_fib.h
@@ -219,7 +219,7 @@  struct fib_nh_notifier_info {
 	struct fib_nh *fib_nh;
 };
 
-int call_fib4_notifier(struct notifier_block *nb, struct net *net,
+int call_fib4_notifier(struct notifier_block *nb,
 		       enum fib_event_type event_type,
 		       struct fib_notifier_info *info);
 int call_fib4_notifiers(struct net *net, enum fib_event_type event_type,
diff --git a/net/core/fib_notifier.c b/net/core/fib_notifier.c
index 470a606d5e8d..b965f3c0ec9a 100644
--- a/net/core/fib_notifier.c
+++ b/net/core/fib_notifier.c
@@ -12,17 +12,15 @@  static unsigned int fib_notifier_net_id;
 
 struct fib_notifier_net {
 	struct list_head fib_notifier_ops;
+	struct atomic_notifier_head fib_chain;
 };
 
-static ATOMIC_NOTIFIER_HEAD(fib_chain);
-
-int call_fib_notifier(struct notifier_block *nb, struct net *net,
+int call_fib_notifier(struct notifier_block *nb,
 		      enum fib_event_type event_type,
 		      struct fib_notifier_info *info)
 {
 	int err;
 
-	info->net = net;
 	err = nb->notifier_call(nb, event_type, info);
 	return notifier_to_errno(err);
 }
@@ -31,35 +29,29 @@  EXPORT_SYMBOL(call_fib_notifier);
 int call_fib_notifiers(struct net *net, enum fib_event_type event_type,
 		       struct fib_notifier_info *info)
 {
+	struct fib_notifier_net *fn_net = net_generic(net, fib_notifier_net_id);
 	int err;
 
-	info->net = net;
-	err = atomic_notifier_call_chain(&fib_chain, event_type, info);
+	err = atomic_notifier_call_chain(&fn_net->fib_chain, event_type, info);
 	return notifier_to_errno(err);
 }
 EXPORT_SYMBOL(call_fib_notifiers);
 
-static unsigned int fib_seq_sum(void)
+static unsigned int fib_seq_sum(struct net *net)
 {
-	struct fib_notifier_net *fn_net;
+	struct fib_notifier_net *fn_net = net_generic(net, fib_notifier_net_id);
 	struct fib_notifier_ops *ops;
 	unsigned int fib_seq = 0;
-	struct net *net;
 
 	rtnl_lock();
-	down_read(&net_rwsem);
-	for_each_net(net) {
-		fn_net = net_generic(net, fib_notifier_net_id);
-		rcu_read_lock();
-		list_for_each_entry_rcu(ops, &fn_net->fib_notifier_ops, list) {
-			if (!try_module_get(ops->owner))
-				continue;
-			fib_seq += ops->fib_seq_read(net);
-			module_put(ops->owner);
-		}
-		rcu_read_unlock();
+	rcu_read_lock();
+	list_for_each_entry_rcu(ops, &fn_net->fib_notifier_ops, list) {
+		if (!try_module_get(ops->owner))
+			continue;
+		fib_seq += ops->fib_seq_read(net);
+		module_put(ops->owner);
 	}
-	up_read(&net_rwsem);
+	rcu_read_unlock();
 	rtnl_unlock();
 
 	return fib_seq;
@@ -69,7 +61,9 @@  static int fib_net_dump(struct net *net, struct notifier_block *nb)
 {
 	struct fib_notifier_net *fn_net = net_generic(net, fib_notifier_net_id);
 	struct fib_notifier_ops *ops;
+	int err = 0;
 
+	rcu_read_lock();
 	list_for_each_entry_rcu(ops, &fn_net->fib_notifier_ops, list) {
 		int err;
 
@@ -78,59 +72,57 @@  static int fib_net_dump(struct net *net, struct notifier_block *nb)
 		err = ops->fib_dump(net, nb);
 		module_put(ops->owner);
 		if (err)
-			return err;
+			goto unlock;
 	}
 
-	return 0;
+unlock:
+	rcu_read_unlock();
+
+	return err;
 }
 
-static bool fib_dump_is_consistent(struct notifier_block *nb,
+static bool fib_dump_is_consistent(struct net *net, struct notifier_block *nb,
 				   void (*cb)(struct notifier_block *nb),
 				   unsigned int fib_seq)
 {
-	atomic_notifier_chain_register(&fib_chain, nb);
-	if (fib_seq == fib_seq_sum())
+	struct fib_notifier_net *fn_net = net_generic(net, fib_notifier_net_id);
+
+	atomic_notifier_chain_register(&fn_net->fib_chain, nb);
+	if (fib_seq == fib_seq_sum(net))
 		return true;
-	atomic_notifier_chain_unregister(&fib_chain, nb);
+	atomic_notifier_chain_unregister(&fn_net->fib_chain, nb);
 	if (cb)
 		cb(nb);
 	return false;
 }
 
 #define FIB_DUMP_MAX_RETRIES 5
-int register_fib_notifier(struct notifier_block *nb,
+int register_fib_notifier(struct net *net, struct notifier_block *nb,
 			  void (*cb)(struct notifier_block *nb))
 {
 	int retries = 0;
 	int err;
 
 	do {
-		unsigned int fib_seq = fib_seq_sum();
-		struct net *net;
-
-		rcu_read_lock();
-		for_each_net_rcu(net) {
-			err = fib_net_dump(net, nb);
-			if (err)
-				goto err_fib_net_dump;
-		}
-		rcu_read_unlock();
-
-		if (fib_dump_is_consistent(nb, cb, fib_seq))
+		unsigned int fib_seq = fib_seq_sum(net);
+
+		err = fib_net_dump(net, nb);
+		if (err)
+			return err;
+
+		if (fib_dump_is_consistent(net, nb, cb, fib_seq))
 			return 0;
 	} while (++retries < FIB_DUMP_MAX_RETRIES);
 
 	return -EBUSY;
-
-err_fib_net_dump:
-	rcu_read_unlock();
-	return err;
 }
 EXPORT_SYMBOL(register_fib_notifier);
 
-int unregister_fib_notifier(struct notifier_block *nb)
+int unregister_fib_notifier(struct net *net, struct notifier_block *nb)
 {
-	return atomic_notifier_chain_unregister(&fib_chain, nb);
+	struct fib_notifier_net *fn_net = net_generic(net, fib_notifier_net_id);
+
+	return atomic_notifier_chain_unregister(&fn_net->fib_chain, nb);
 }
 EXPORT_SYMBOL(unregister_fib_notifier);
 
@@ -181,6 +173,7 @@  static int __net_init fib_notifier_net_init(struct net *net)
 	struct fib_notifier_net *fn_net = net_generic(net, fib_notifier_net_id);
 
 	INIT_LIST_HEAD(&fn_net->fib_notifier_ops);
+	ATOMIC_INIT_NOTIFIER_HEAD(&fn_net->fib_chain);
 	return 0;
 }
 
diff --git a/net/core/fib_rules.c b/net/core/fib_rules.c
index dd220ce7ca7a..28cbf07102bc 100644
--- a/net/core/fib_rules.c
+++ b/net/core/fib_rules.c
@@ -321,7 +321,7 @@  int fib_rules_lookup(struct fib_rules_ops *ops, struct flowi *fl,
 }
 EXPORT_SYMBOL_GPL(fib_rules_lookup);
 
-static int call_fib_rule_notifier(struct notifier_block *nb, struct net *net,
+static int call_fib_rule_notifier(struct notifier_block *nb,
 				  enum fib_event_type event_type,
 				  struct fib_rule *rule, int family)
 {
@@ -330,7 +330,7 @@  static int call_fib_rule_notifier(struct notifier_block *nb, struct net *net,
 		.rule = rule,
 	};
 
-	return call_fib_notifier(nb, net, event_type, &info.info);
+	return call_fib_notifier(nb, event_type, &info.info);
 }
 
 static int call_fib_rule_notifiers(struct net *net,
@@ -359,8 +359,7 @@  int fib_rules_dump(struct net *net, struct notifier_block *nb, int family)
 	if (!ops)
 		return -EAFNOSUPPORT;
 	list_for_each_entry_rcu(rule, &ops->rules_list, list)
-		call_fib_rule_notifier(nb, net, FIB_EVENT_RULE_ADD, rule,
-				       family);
+		call_fib_rule_notifier(nb, FIB_EVENT_RULE_ADD, rule, family);
 	rules_ops_put(ops);
 
 	return 0;
diff --git a/net/ipv4/fib_notifier.c b/net/ipv4/fib_notifier.c
index b804ccbdb241..1a128c1346fb 100644
--- a/net/ipv4/fib_notifier.c
+++ b/net/ipv4/fib_notifier.c
@@ -9,12 +9,12 @@ 
 #include <net/netns/ipv4.h>
 #include <net/ip_fib.h>
 
-int call_fib4_notifier(struct notifier_block *nb, struct net *net,
+int call_fib4_notifier(struct notifier_block *nb,
 		       enum fib_event_type event_type,
 		       struct fib_notifier_info *info)
 {
 	info->family = AF_INET;
-	return call_fib_notifier(nb, net, event_type, info);
+	return call_fib_notifier(nb, event_type, info);
 }
 
 int call_fib4_notifiers(struct net *net, enum fib_event_type event_type,
diff --git a/net/ipv4/fib_trie.c b/net/ipv4/fib_trie.c
index 1ab2fb6bb37d..5b600b2a2aa3 100644
--- a/net/ipv4/fib_trie.c
+++ b/net/ipv4/fib_trie.c
@@ -74,7 +74,7 @@ 
 #include <trace/events/fib.h>
 #include "fib_lookup.h"
 
-static int call_fib_entry_notifier(struct notifier_block *nb, struct net *net,
+static int call_fib_entry_notifier(struct notifier_block *nb,
 				   enum fib_event_type event_type, u32 dst,
 				   int dst_len, struct fib_alias *fa)
 {
@@ -86,7 +86,7 @@  static int call_fib_entry_notifier(struct notifier_block *nb, struct net *net,
 		.type = fa->fa_type,
 		.tb_id = fa->tb_id,
 	};
-	return call_fib4_notifier(nb, net, event_type, &info.info);
+	return call_fib4_notifier(nb, event_type, &info.info);
 }
 
 static int call_fib_entry_notifiers(struct net *net,
@@ -2015,8 +2015,8 @@  void fib_info_notify_update(struct net *net, struct nl_info *info)
 	}
 }
 
-static void fib_leaf_notify(struct net *net, struct key_vector *l,
-			    struct fib_table *tb, struct notifier_block *nb)
+static void fib_leaf_notify(struct key_vector *l, struct fib_table *tb,
+			    struct notifier_block *nb)
 {
 	struct fib_alias *fa;
 
@@ -2032,20 +2032,19 @@  static void fib_leaf_notify(struct net *net, struct key_vector *l,
 		if (tb->tb_id != fa->tb_id)
 			continue;
 
-		call_fib_entry_notifier(nb, net, FIB_EVENT_ENTRY_ADD, l->key,
+		call_fib_entry_notifier(nb, FIB_EVENT_ENTRY_ADD, l->key,
 					KEYLENGTH - fa->fa_slen, fa);
 	}
 }
 
-static void fib_table_notify(struct net *net, struct fib_table *tb,
-			     struct notifier_block *nb)
+static void fib_table_notify(struct fib_table *tb, struct notifier_block *nb)
 {
 	struct trie *t = (struct trie *)tb->tb_data;
 	struct key_vector *l, *tp = t->kv;
 	t_key key = 0;
 
 	while ((l = leaf_walk_rcu(&tp, key)) != NULL) {
-		fib_leaf_notify(net, l, tb, nb);
+		fib_leaf_notify(l, tb, nb);
 
 		key = l->key + 1;
 		/* stop in case of wrap around */
@@ -2063,7 +2062,7 @@  void fib_notify(struct net *net, struct notifier_block *nb)
 		struct fib_table *tb;
 
 		hlist_for_each_entry_rcu(tb, head, tb_hlist)
-			fib_table_notify(net, tb, nb);
+			fib_table_notify(tb, nb);
 	}
 }
 
diff --git a/net/ipv4/ipmr_base.c b/net/ipv4/ipmr_base.c
index ea48bd15a575..4dcc3214e3cc 100644
--- a/net/ipv4/ipmr_base.c
+++ b/net/ipv4/ipmr_base.c
@@ -409,7 +409,7 @@  int mr_dump(struct net *net, struct notifier_block *nb, unsigned short family,
 			if (!v->dev)
 				continue;
 
-			mr_call_vif_notifier(nb, net, family,
+			mr_call_vif_notifier(nb, family,
 					     FIB_EVENT_VIF_ADD,
 					     v, vifi, mrt->id);
 		}
@@ -417,7 +417,7 @@  int mr_dump(struct net *net, struct notifier_block *nb, unsigned short family,
 
 		/* Notify on table MFC entries */
 		list_for_each_entry_rcu(mfc, &mrt->mfc_cache_list, list)
-			mr_call_mfc_notifier(nb, net, family,
+			mr_call_mfc_notifier(nb, family,
 					     FIB_EVENT_ENTRY_ADD,
 					     mfc, mrt->id);
 	}
diff --git a/net/ipv6/fib6_notifier.c b/net/ipv6/fib6_notifier.c
index 05f82baaa99e..4fe79296999a 100644
--- a/net/ipv6/fib6_notifier.c
+++ b/net/ipv6/fib6_notifier.c
@@ -7,12 +7,12 @@ 
 #include <net/netns/ipv6.h>
 #include <net/ip6_fib.h>
 
-int call_fib6_notifier(struct notifier_block *nb, struct net *net,
+int call_fib6_notifier(struct notifier_block *nb,
 		       enum fib_event_type event_type,
 		       struct fib_notifier_info *info)
 {
 	info->family = AF_INET6;
-	return call_fib_notifier(nb, net, event_type, info);
+	return call_fib_notifier(nb, event_type, info);
 }
 
 int call_fib6_notifiers(struct net *net, enum fib_event_type event_type,
diff --git a/net/ipv6/ip6_fib.c b/net/ipv6/ip6_fib.c
index 87f47bc55c5e..a6d500023457 100644
--- a/net/ipv6/ip6_fib.c
+++ b/net/ipv6/ip6_fib.c
@@ -357,7 +357,7 @@  unsigned int fib6_tables_seq_read(struct net *net)
 	return fib_seq;
 }
 
-static int call_fib6_entry_notifier(struct notifier_block *nb, struct net *net,
+static int call_fib6_entry_notifier(struct notifier_block *nb,
 				    enum fib_event_type event_type,
 				    struct fib6_info *rt)
 {
@@ -365,7 +365,7 @@  static int call_fib6_entry_notifier(struct notifier_block *nb, struct net *net,
 		.rt = rt,
 	};
 
-	return call_fib6_notifier(nb, net, event_type, &info.info);
+	return call_fib6_notifier(nb, event_type, &info.info);
 }
 
 int call_fib6_entry_notifiers(struct net *net,
@@ -407,7 +407,7 @@  static void fib6_rt_dump(struct fib6_info *rt, struct fib6_dump_arg *arg)
 {
 	if (rt == arg->net->ipv6.fib6_null_entry)
 		return;
-	call_fib6_entry_notifier(arg->nb, arg->net, FIB_EVENT_ENTRY_ADD, rt);
+	call_fib6_entry_notifier(arg->nb, FIB_EVENT_ENTRY_ADD, rt);
 }
 
 static int fib6_node_dump(struct fib6_walker *w)