From eec94fdb04806790c7b7e6ea347820064cc6d467 Mon Sep 17 00:00:00 2001 From: Vlad Buslov Date: Thu, 5 Jul 2018 17:24:23 +0300 Subject: net: sched: use rcu for action cookie update Implement functions to atomically update and free action cookie using rcu mechanism. Reviewed-by: Marcelo Ricardo Leitner Signed-off-by: Vlad Buslov Signed-off-by: Jiri Pirko Signed-off-by: David S. Miller --- include/net/act_api.h | 2 +- include/net/pkt_cls.h | 1 + 2 files changed, 2 insertions(+), 1 deletion(-) (limited to 'include') diff --git a/include/net/act_api.h b/include/net/act_api.h index 5ff11adbe2a6..ffc3ef321776 100644 --- a/include/net/act_api.h +++ b/include/net/act_api.h @@ -37,7 +37,7 @@ struct tc_action { spinlock_t tcfa_lock; struct gnet_stats_basic_cpu __percpu *cpu_bstats; struct gnet_stats_queue __percpu *cpu_qstats; - struct tc_cookie *act_cookie; + struct tc_cookie __rcu *act_cookie; struct tcf_chain *goto_chain; }; #define tcf_index common.tcfa_index diff --git a/include/net/pkt_cls.h b/include/net/pkt_cls.h index 6641584b27f1..2081e4219f81 100644 --- a/include/net/pkt_cls.h +++ b/include/net/pkt_cls.h @@ -781,6 +781,7 @@ struct tc_mqprio_qopt_offload { struct tc_cookie { u8 *data; u32 len; + struct rcu_head rcu; }; struct tc_qopt_offload_stats { -- cgit v1.2.3 From 036bb44327f50273e85ee4a2c9b56eebce1c0838 Mon Sep 17 00:00:00 2001 From: Vlad Buslov Date: Thu, 5 Jul 2018 17:24:24 +0300 Subject: net: sched: change type of reference and bind counters Change type of action reference counter to refcount_t. Change type of action bind counter to atomic_t. This type is used to allow decrementing bind counter without testing for 0 result. Reviewed-by: Marcelo Ricardo Leitner Signed-off-by: Vlad Buslov Signed-off-by: Jiri Pirko Signed-off-by: David S. Miller --- include/net/act_api.h | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-) (limited to 'include') diff --git a/include/net/act_api.h b/include/net/act_api.h index ffc3ef321776..2759226527a2 100644 --- a/include/net/act_api.h +++ b/include/net/act_api.h @@ -6,6 +6,7 @@ * Public action API for classifiers/qdiscs */ +#include #include #include #include @@ -26,8 +27,8 @@ struct tc_action { struct tcf_idrinfo *idrinfo; u32 tcfa_index; - int tcfa_refcnt; - int tcfa_bindcnt; + refcount_t tcfa_refcnt; + atomic_t tcfa_bindcnt; u32 tcfa_capab; int tcfa_action; struct tcf_t tcfa_tm; -- cgit v1.2.3 From 789871bb2a0381425b106d2a995bde1460d35a34 Mon Sep 17 00:00:00 2001 From: Vlad Buslov Date: Thu, 5 Jul 2018 17:24:25 +0300 Subject: net: sched: implement unlocked action init API Add additional 'rtnl_held' argument to act API init functions. It is required to implement actions that need to release rtnl lock before loading kernel module and reacquire if afterwards. Reviewed-by: Marcelo Ricardo Leitner Signed-off-by: Vlad Buslov Signed-off-by: Jiri Pirko Signed-off-by: David S. Miller --- include/net/act_api.h | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-) (limited to 'include') diff --git a/include/net/act_api.h b/include/net/act_api.h index 2759226527a2..27823f4e24c4 100644 --- a/include/net/act_api.h +++ b/include/net/act_api.h @@ -92,7 +92,8 @@ struct tc_action_ops { struct netlink_ext_ack *extack); int (*init)(struct net *net, struct nlattr *nla, struct nlattr *est, struct tc_action **act, int ovr, - int bind, struct netlink_ext_ack *extack); + int bind, bool rtnl_held, + struct netlink_ext_ack *extack); int (*walk)(struct net *, struct sk_buff *, struct netlink_callback *, int, const struct tc_action_ops *, @@ -168,10 +169,11 @@ int tcf_action_exec(struct sk_buff *skb, struct tc_action **actions, int tcf_action_init(struct net *net, struct tcf_proto *tp, struct nlattr *nla, struct nlattr *est, char *name, int ovr, int bind, struct list_head *actions, size_t *attr_size, - struct netlink_ext_ack *extack); + bool rtnl_held, struct netlink_ext_ack *extack); struct tc_action *tcf_action_init_1(struct net *net, struct tcf_proto *tp, struct nlattr *nla, struct nlattr *est, char *name, int ovr, int bind, + bool rtnl_held, struct netlink_ext_ack *extack); int tcf_action_dump(struct sk_buff *skb, struct list_head *, int, int); int tcf_action_dump_old(struct sk_buff *skb, struct tc_action *a, int, int); -- cgit v1.2.3 From 2a2ea349704fffade9526d5122299edbbfd122ca Mon Sep 17 00:00:00 2001 From: Vlad Buslov Date: Thu, 5 Jul 2018 17:24:27 +0300 Subject: net: sched: implement action API that deletes action by index Implement new action API function that atomically finds and deletes action from idr by index. Intended to be used by lockless actions that do not rely on rtnl lock. Reviewed-by: Marcelo Ricardo Leitner Signed-off-by: Vlad Buslov Signed-off-by: Jiri Pirko Signed-off-by: David S. Miller --- include/net/act_api.h | 1 + 1 file changed, 1 insertion(+) (limited to 'include') diff --git a/include/net/act_api.h b/include/net/act_api.h index 27823f4e24c4..a8eaae67c264 100644 --- a/include/net/act_api.h +++ b/include/net/act_api.h @@ -153,6 +153,7 @@ int tcf_idr_create(struct tc_action_net *tn, u32 index, struct nlattr *est, int bind, bool cpustats); void tcf_idr_insert(struct tc_action_net *tn, struct tc_action *a); +int tcf_idr_delete_index(struct tc_action_net *tn, u32 index); int __tcf_idr_release(struct tc_action *a, bool bind, bool strict); static inline int tcf_idr_release(struct tc_action *a, bool bind) -- cgit v1.2.3 From b409074e6693bcdaa7abbee2a035f22a9eabda53 Mon Sep 17 00:00:00 2001 From: Vlad Buslov Date: Thu, 5 Jul 2018 17:24:28 +0300 Subject: net: sched: add 'delete' function to action ops Extend action ops with 'delete' function. Each action type to implements its own delete function that doesn't depend on rtnl lock. Implement delete function that is required to delete actions without holding rtnl lock. Use action API function that atomically deletes action only if it is still in action idr. This implementation prevents concurrent threads from deleting same action twice. Reviewed-by: Marcelo Ricardo Leitner Signed-off-by: Vlad Buslov Signed-off-by: Jiri Pirko Signed-off-by: David S. Miller --- include/net/act_api.h | 1 + 1 file changed, 1 insertion(+) (limited to 'include') diff --git a/include/net/act_api.h b/include/net/act_api.h index a8eaae67c264..b9ed2b8256a5 100644 --- a/include/net/act_api.h +++ b/include/net/act_api.h @@ -101,6 +101,7 @@ struct tc_action_ops { void (*stats_update)(struct tc_action *, u64, u32, u64); size_t (*get_fill_size)(const struct tc_action *act); struct net_device *(*get_dev)(const struct tc_action *a); + int (*delete)(struct net *net, u32 index); }; struct tc_action_net { -- cgit v1.2.3 From 0190c1d452a91c38a3462abdd81752be1b9006a8 Mon Sep 17 00:00:00 2001 From: Vlad Buslov Date: Thu, 5 Jul 2018 17:24:32 +0300 Subject: net: sched: atomically check-allocate action Implement function that atomically checks if action exists and either takes reference to it, or allocates idr slot for action index to prevent concurrent allocations of actions with same index. Use EBUSY error pointer to indicate that idr slot is reserved. Implement cleanup helper function that removes temporary error pointer from idr. (in case of error between idr allocation and insertion of newly created action to specified index) Refactor all action init functions to insert new action to idr using this API. Reviewed-by: Marcelo Ricardo Leitner Signed-off-by: Vlad Buslov Signed-off-by: Jiri Pirko Signed-off-by: David S. Miller --- include/net/act_api.h | 3 +++ 1 file changed, 3 insertions(+) (limited to 'include') diff --git a/include/net/act_api.h b/include/net/act_api.h index b9ed2b8256a5..8090de2edab7 100644 --- a/include/net/act_api.h +++ b/include/net/act_api.h @@ -154,6 +154,9 @@ int tcf_idr_create(struct tc_action_net *tn, u32 index, struct nlattr *est, int bind, bool cpustats); void tcf_idr_insert(struct tc_action_net *tn, struct tc_action *a); +void tcf_idr_cleanup(struct tc_action_net *tn, u32 index); +int tcf_idr_check_alloc(struct tc_action_net *tn, u32 *index, + struct tc_action **a, int bind); int tcf_idr_delete_index(struct tc_action_net *tn, u32 index); int __tcf_idr_release(struct tc_action *a, bool bind, bool strict); -- cgit v1.2.3 From 90b73b77d08ec395311411b545c756ca710aae59 Mon Sep 17 00:00:00 2001 From: Vlad Buslov Date: Thu, 5 Jul 2018 17:24:33 +0300 Subject: net: sched: change action API to use array of pointers to actions Act API used linked list to pass set of actions to functions. It is intrusive data structure that stores list nodes inside action structure itself, which means it is not safe to modify such list concurrently. However, action API doesn't use any linked list specific operations on this set of actions, so it can be safely refactored into plain pointer array. Refactor action API to use array of pointers to tc_actions instead of linked list. Change argument 'actions' type of exported action init, destroy and dump functions. Acked-by: Jiri Pirko Signed-off-by: Vlad Buslov Signed-off-by: David S. Miller --- include/net/act_api.h | 7 ++++--- 1 file changed, 4 insertions(+), 3 deletions(-) (limited to 'include') diff --git a/include/net/act_api.h b/include/net/act_api.h index 8090de2edab7..683ce41053d9 100644 --- a/include/net/act_api.h +++ b/include/net/act_api.h @@ -168,19 +168,20 @@ static inline int tcf_idr_release(struct tc_action *a, bool bind) int tcf_register_action(struct tc_action_ops *a, struct pernet_operations *ops); int tcf_unregister_action(struct tc_action_ops *a, struct pernet_operations *ops); -int tcf_action_destroy(struct list_head *actions, int bind); +int tcf_action_destroy(struct tc_action *actions[], int bind); int tcf_action_exec(struct sk_buff *skb, struct tc_action **actions, int nr_actions, struct tcf_result *res); int tcf_action_init(struct net *net, struct tcf_proto *tp, struct nlattr *nla, struct nlattr *est, char *name, int ovr, int bind, - struct list_head *actions, size_t *attr_size, + struct tc_action *actions[], size_t *attr_size, bool rtnl_held, struct netlink_ext_ack *extack); struct tc_action *tcf_action_init_1(struct net *net, struct tcf_proto *tp, struct nlattr *nla, struct nlattr *est, char *name, int ovr, int bind, bool rtnl_held, struct netlink_ext_ack *extack); -int tcf_action_dump(struct sk_buff *skb, struct list_head *, int, int); +int tcf_action_dump(struct sk_buff *skb, struct tc_action *actions[], int bind, + int ref); int tcf_action_dump_old(struct sk_buff *skb, struct tc_action *a, int, int); int tcf_action_dump_1(struct sk_buff *skb, struct tc_action *a, int, int); int tcf_action_copy_stats(struct sk_buff *, struct tc_action *, int); -- cgit v1.2.3