diff options
-rw-r--r-- | net/netfilter/ipvs/ip_vs_dh.c | 81 |
1 files changed, 45 insertions, 36 deletions
diff --git a/net/netfilter/ipvs/ip_vs_dh.c b/net/netfilter/ipvs/ip_vs_dh.c index 7f3b0cc00b7a..ebe80f44e712 100644 --- a/net/netfilter/ipvs/ip_vs_dh.c +++ b/net/netfilter/ipvs/ip_vs_dh.c @@ -51,7 +51,7 @@ * IPVS DH bucket */ struct ip_vs_dh_bucket { - struct ip_vs_dest *dest; /* real server (cache) */ + struct ip_vs_dest __rcu *dest; /* real server (cache) */ }; /* @@ -64,6 +64,10 @@ struct ip_vs_dh_bucket { #define IP_VS_DH_TAB_SIZE (1 << IP_VS_DH_TAB_BITS) #define IP_VS_DH_TAB_MASK (IP_VS_DH_TAB_SIZE - 1) +struct ip_vs_dh_state { + struct ip_vs_dh_bucket buckets[IP_VS_DH_TAB_SIZE]; + struct rcu_head rcu_head; +}; /* * Returns hash value for IPVS DH entry @@ -85,10 +89,9 @@ static inline unsigned int ip_vs_dh_hashkey(int af, const union nf_inet_addr *ad * Get ip_vs_dest associated with supplied parameters. */ static inline struct ip_vs_dest * -ip_vs_dh_get(int af, struct ip_vs_dh_bucket *tbl, - const union nf_inet_addr *addr) +ip_vs_dh_get(int af, struct ip_vs_dh_state *s, const union nf_inet_addr *addr) { - return (tbl[ip_vs_dh_hashkey(af, addr)]).dest; + return rcu_dereference(s->buckets[ip_vs_dh_hashkey(af, addr)].dest); } @@ -96,25 +99,30 @@ ip_vs_dh_get(int af, struct ip_vs_dh_bucket *tbl, * Assign all the hash buckets of the specified table with the service. */ static int -ip_vs_dh_assign(struct ip_vs_dh_bucket *tbl, struct ip_vs_service *svc) +ip_vs_dh_reassign(struct ip_vs_dh_state *s, struct ip_vs_service *svc) { int i; struct ip_vs_dh_bucket *b; struct list_head *p; struct ip_vs_dest *dest; + bool empty; - b = tbl; + b = &s->buckets[0]; p = &svc->destinations; + empty = list_empty(p); for (i=0; i<IP_VS_DH_TAB_SIZE; i++) { - if (list_empty(p)) { - b->dest = NULL; - } else { + dest = rcu_dereference_protected(b->dest, 1); + if (dest) + ip_vs_dest_put(dest); + if (empty) + RCU_INIT_POINTER(b->dest, NULL); + else { if (p == &svc->destinations) p = p->next; dest = list_entry(p, struct ip_vs_dest, n_list); - atomic_inc(&dest->refcnt); - b->dest = dest; + ip_vs_dest_hold(dest); + RCU_INIT_POINTER(b->dest, dest); p = p->next; } @@ -127,16 +135,18 @@ ip_vs_dh_assign(struct ip_vs_dh_bucket *tbl, struct ip_vs_service *svc) /* * Flush all the hash buckets of the specified table. */ -static void ip_vs_dh_flush(struct ip_vs_dh_bucket *tbl) +static void ip_vs_dh_flush(struct ip_vs_dh_state *s) { int i; struct ip_vs_dh_bucket *b; + struct ip_vs_dest *dest; - b = tbl; + b = &s->buckets[0]; for (i=0; i<IP_VS_DH_TAB_SIZE; i++) { - if (b->dest) { - atomic_dec(&b->dest->refcnt); - b->dest = NULL; + dest = rcu_dereference_protected(b->dest, 1); + if (dest) { + ip_vs_dest_put(dest); + RCU_INIT_POINTER(b->dest, NULL); } b++; } @@ -145,21 +155,20 @@ static void ip_vs_dh_flush(struct ip_vs_dh_bucket *tbl) static int ip_vs_dh_init_svc(struct ip_vs_service *svc) { - struct ip_vs_dh_bucket *tbl; + struct ip_vs_dh_state *s; /* allocate the DH table for this service */ - tbl = kmalloc(sizeof(struct ip_vs_dh_bucket)*IP_VS_DH_TAB_SIZE, - GFP_KERNEL); - if (tbl == NULL) + s = kzalloc(sizeof(struct ip_vs_dh_state), GFP_KERNEL); + if (s == NULL) return -ENOMEM; - svc->sched_data = tbl; + svc->sched_data = s; IP_VS_DBG(6, "DH hash table (memory=%Zdbytes) allocated for " "current service\n", sizeof(struct ip_vs_dh_bucket)*IP_VS_DH_TAB_SIZE); - /* assign the hash buckets with the updated service */ - ip_vs_dh_assign(tbl, svc); + /* assign the hash buckets with current dests */ + ip_vs_dh_reassign(s, svc); return 0; } @@ -167,13 +176,13 @@ static int ip_vs_dh_init_svc(struct ip_vs_service *svc) static int ip_vs_dh_done_svc(struct ip_vs_service *svc) { - struct ip_vs_dh_bucket *tbl = svc->sched_data; + struct ip_vs_dh_state *s = svc->sched_data; /* got to clean up hash buckets here */ - ip_vs_dh_flush(tbl); + ip_vs_dh_flush(s); /* release the table itself */ - kfree(svc->sched_data); + kfree_rcu(s, rcu_head); IP_VS_DBG(6, "DH hash table (memory=%Zdbytes) released\n", sizeof(struct ip_vs_dh_bucket)*IP_VS_DH_TAB_SIZE); @@ -181,15 +190,13 @@ static int ip_vs_dh_done_svc(struct ip_vs_service *svc) } -static int ip_vs_dh_update_svc(struct ip_vs_service *svc) +static int ip_vs_dh_dest_changed(struct ip_vs_service *svc, + struct ip_vs_dest *dest) { - struct ip_vs_dh_bucket *tbl = svc->sched_data; - - /* got to clean up hash buckets here */ - ip_vs_dh_flush(tbl); + struct ip_vs_dh_state *s = svc->sched_data; /* assign the hash buckets with the updated service */ - ip_vs_dh_assign(tbl, svc); + ip_vs_dh_reassign(s, svc); return 0; } @@ -212,19 +219,20 @@ static struct ip_vs_dest * ip_vs_dh_schedule(struct ip_vs_service *svc, const struct sk_buff *skb) { struct ip_vs_dest *dest; - struct ip_vs_dh_bucket *tbl; + struct ip_vs_dh_state *s; struct ip_vs_iphdr iph; ip_vs_fill_iph_addr_only(svc->af, skb, &iph); IP_VS_DBG(6, "%s(): Scheduling...\n", __func__); - tbl = (struct ip_vs_dh_bucket *)svc->sched_data; - dest = ip_vs_dh_get(svc->af, tbl, &iph.daddr); + s = (struct ip_vs_dh_state *) svc->sched_data; + dest = ip_vs_dh_get(svc->af, s, &iph.daddr); if (!dest || !(dest->flags & IP_VS_DEST_F_AVAILABLE) || atomic_read(&dest->weight) <= 0 || is_overloaded(dest)) { + ip_vs_scheduler_err(svc, "no destination available"); return NULL; } @@ -248,7 +256,8 @@ static struct ip_vs_scheduler ip_vs_dh_scheduler = .n_list = LIST_HEAD_INIT(ip_vs_dh_scheduler.n_list), .init_service = ip_vs_dh_init_svc, .done_service = ip_vs_dh_done_svc, - .update_service = ip_vs_dh_update_svc, + .add_dest = ip_vs_dh_dest_changed, + .del_dest = ip_vs_dh_dest_changed, .schedule = ip_vs_dh_schedule, }; 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