From 1acb7f6761626f4834ea5ce16d8a4dd2a5dd1949 Mon Sep 17 00:00:00 2001 From: Julian Anastasov Date: Fri, 22 Mar 2013 11:46:46 +0200 Subject: [PATCH] ipvs: convert sh scheduler to rcu Use the 3 new methods to reassign dests. Signed-off-by: Julian Anastasov Signed-off-by: Simon Horman --- net/netfilter/ipvs/ip_vs_sh.c | 81 +++++++++++++++++++---------------- 1 file changed, 45 insertions(+), 36 deletions(-) diff --git a/net/netfilter/ipvs/ip_vs_sh.c b/net/netfilter/ipvs/ip_vs_sh.c index e33126994628..55e76d8db711 100644 --- a/net/netfilter/ipvs/ip_vs_sh.c +++ b/net/netfilter/ipvs/ip_vs_sh.c @@ -53,7 +53,7 @@ * IPVS SH bucket */ struct ip_vs_sh_bucket { - struct ip_vs_dest *dest; /* real server (cache) */ + struct ip_vs_dest __rcu *dest; /* real server (cache) */ }; /* @@ -66,6 +66,10 @@ struct ip_vs_sh_bucket { #define IP_VS_SH_TAB_SIZE (1 << IP_VS_SH_TAB_BITS) #define IP_VS_SH_TAB_MASK (IP_VS_SH_TAB_SIZE - 1) +struct ip_vs_sh_state { + struct ip_vs_sh_bucket buckets[IP_VS_SH_TAB_SIZE]; + struct rcu_head rcu_head; +}; /* * Returns hash value for IPVS SH entry @@ -87,10 +91,9 @@ static inline unsigned int ip_vs_sh_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_sh_get(int af, struct ip_vs_sh_bucket *tbl, - const union nf_inet_addr *addr) +ip_vs_sh_get(int af, struct ip_vs_sh_state *s, const union nf_inet_addr *addr) { - return (tbl[ip_vs_sh_hashkey(af, addr)]).dest; + return rcu_dereference(s->buckets[ip_vs_sh_hashkey(af, addr)].dest); } @@ -98,27 +101,32 @@ ip_vs_sh_get(int af, struct ip_vs_sh_bucket *tbl, * Assign all the hash buckets of the specified table with the service. */ static int -ip_vs_sh_assign(struct ip_vs_sh_bucket *tbl, struct ip_vs_service *svc) +ip_vs_sh_reassign(struct ip_vs_sh_state *s, struct ip_vs_service *svc) { int i; struct ip_vs_sh_bucket *b; struct list_head *p; struct ip_vs_dest *dest; int d_count; + bool empty; - b = tbl; + b = &s->buckets[0]; p = &svc->destinations; + empty = list_empty(p); d_count = 0; for (i=0; idest = 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); IP_VS_DBG_BUF(6, "assigned i: %d dest: %s weight: %d\n", i, IP_VS_DBG_ADDR(svc->af, &dest->addr), @@ -140,16 +148,18 @@ ip_vs_sh_assign(struct ip_vs_sh_bucket *tbl, struct ip_vs_service *svc) /* * Flush all the hash buckets of the specified table. */ -static void ip_vs_sh_flush(struct ip_vs_sh_bucket *tbl) +static void ip_vs_sh_flush(struct ip_vs_sh_state *s) { int i; struct ip_vs_sh_bucket *b; + struct ip_vs_dest *dest; - b = tbl; + b = &s->buckets[0]; for (i=0; idest) { - 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++; } @@ -158,21 +168,20 @@ static void ip_vs_sh_flush(struct ip_vs_sh_bucket *tbl) static int ip_vs_sh_init_svc(struct ip_vs_service *svc) { - struct ip_vs_sh_bucket *tbl; + struct ip_vs_sh_state *s; /* allocate the SH table for this service */ - tbl = kmalloc(sizeof(struct ip_vs_sh_bucket)*IP_VS_SH_TAB_SIZE, - GFP_KERNEL); - if (tbl == NULL) + s = kzalloc(sizeof(struct ip_vs_sh_state), GFP_KERNEL); + if (s == NULL) return -ENOMEM; - svc->sched_data = tbl; + svc->sched_data = s; IP_VS_DBG(6, "SH hash table (memory=%Zdbytes) allocated for " "current service\n", sizeof(struct ip_vs_sh_bucket)*IP_VS_SH_TAB_SIZE); - /* assign the hash buckets with the updated service */ - ip_vs_sh_assign(tbl, svc); + /* assign the hash buckets with current dests */ + ip_vs_sh_reassign(s, svc); return 0; } @@ -180,13 +189,13 @@ static int ip_vs_sh_init_svc(struct ip_vs_service *svc) static int ip_vs_sh_done_svc(struct ip_vs_service *svc) { - struct ip_vs_sh_bucket *tbl = svc->sched_data; + struct ip_vs_sh_state *s = svc->sched_data; /* got to clean up hash buckets here */ - ip_vs_sh_flush(tbl); + ip_vs_sh_flush(s); /* release the table itself */ - kfree(svc->sched_data); + kfree_rcu(s, rcu_head); IP_VS_DBG(6, "SH hash table (memory=%Zdbytes) released\n", sizeof(struct ip_vs_sh_bucket)*IP_VS_SH_TAB_SIZE); @@ -194,15 +203,13 @@ static int ip_vs_sh_done_svc(struct ip_vs_service *svc) } -static int ip_vs_sh_update_svc(struct ip_vs_service *svc) +static int ip_vs_sh_dest_changed(struct ip_vs_service *svc, + struct ip_vs_dest *dest) { - struct ip_vs_sh_bucket *tbl = svc->sched_data; - - /* got to clean up hash buckets here */ - ip_vs_sh_flush(tbl); + struct ip_vs_sh_state *s = svc->sched_data; /* assign the hash buckets with the updated service */ - ip_vs_sh_assign(tbl, svc); + ip_vs_sh_reassign(s, svc); return 0; } @@ -225,15 +232,15 @@ static struct ip_vs_dest * ip_vs_sh_schedule(struct ip_vs_service *svc, const struct sk_buff *skb) { struct ip_vs_dest *dest; - struct ip_vs_sh_bucket *tbl; + struct ip_vs_sh_state *s; struct ip_vs_iphdr iph; ip_vs_fill_iph_addr_only(svc->af, skb, &iph); IP_VS_DBG(6, "ip_vs_sh_schedule(): Scheduling...\n"); - tbl = (struct ip_vs_sh_bucket *)svc->sched_data; - dest = ip_vs_sh_get(svc->af, tbl, &iph.saddr); + s = (struct ip_vs_sh_state *) svc->sched_data; + dest = ip_vs_sh_get(svc->af, s, &iph.saddr); if (!dest || !(dest->flags & IP_VS_DEST_F_AVAILABLE) || atomic_read(&dest->weight) <= 0 @@ -262,7 +269,9 @@ static struct ip_vs_scheduler ip_vs_sh_scheduler = .n_list = LIST_HEAD_INIT(ip_vs_sh_scheduler.n_list), .init_service = ip_vs_sh_init_svc, .done_service = ip_vs_sh_done_svc, - .update_service = ip_vs_sh_update_svc, + .add_dest = ip_vs_sh_dest_changed, + .del_dest = ip_vs_sh_dest_changed, + .upd_dest = ip_vs_sh_dest_changed, .schedule = ip_vs_sh_schedule, }; -- 2.20.1