From ceec4c3816818459d90c92152e61371ff5b1d5a1 Mon Sep 17 00:00:00 2001 From: Julian Anastasov Date: Fri, 22 Mar 2013 11:46:53 +0200 Subject: ipvs: convert services to rcu This is the final step in RCU conversion. Things that are removed: - svc->usecnt: now svc is accessed under RCU read lock - svc->inc: and some unused code - ip_vs_bind_pe and ip_vs_unbind_pe: no ability to replace PE - __ip_vs_svc_lock: replaced with RCU - IP_VS_WAIT_WHILE: now readers lookup svcs and dests under RCU and work in parallel with configuration Other changes: - before now, a RCU read-side critical section included the calling of the schedule method, now it is extended to include service lookup - ip_vs_svc_table and ip_vs_svc_fwm_table are now using hlist - svc->pe and svc->scheduler remain to the end (of grace period), the schedulers are prepared for such RCU readers even after done_service is called but they need to use synchronize_rcu because last ip_vs_scheduler_put can happen while RCU read-side critical sections use an outdated svc->scheduler pointer - as planned, update_service is removed - empty services can be freed immediately after grace period. If dests were present, the services are freed from the dest trash code Signed-off-by: Julian Anastasov Signed-off-by: Simon Horman --- include/net/ip_vs.h | 28 +++++++++------------------- 1 file changed, 9 insertions(+), 19 deletions(-) (limited to 'include/net') diff --git a/include/net/ip_vs.h b/include/net/ip_vs.h index 78a6634..f9f5b05 100644 --- a/include/net/ip_vs.h +++ b/include/net/ip_vs.h @@ -359,8 +359,6 @@ static inline const char *ip_vs_dbg_addr(int af, char *buf, size_t buf_len, #define LeaveFunction(level) do {} while (0) #endif -#define IP_VS_WAIT_WHILE(expr) while (expr) { cpu_relax(); } - /* * The port number of FTP service (in network order). @@ -712,10 +710,9 @@ struct ip_vs_dest_user_kern { * and the forwarding entries */ struct ip_vs_service { - struct list_head s_list; /* for normal service table */ - struct list_head f_list; /* for fwmark-based service table */ + struct hlist_node s_list; /* for normal service table */ + struct hlist_node f_list; /* for fwmark-based service table */ atomic_t refcnt; /* reference counter */ - atomic_t usecnt; /* use counter */ u16 af; /* address family */ __u16 protocol; /* which protocol (TCP/UDP) */ @@ -730,15 +727,16 @@ struct ip_vs_service { struct list_head destinations; /* real server d-linked list */ __u32 num_dests; /* number of servers */ struct ip_vs_stats stats; /* statistics for the service */ - struct ip_vs_app *inc; /* bind conns to this app inc */ /* for scheduling */ - struct ip_vs_scheduler *scheduler; /* bound scheduler object */ + struct ip_vs_scheduler __rcu *scheduler; /* bound scheduler object */ spinlock_t sched_lock; /* lock sched_data */ void *sched_data; /* scheduler application data */ /* alternate persistence engine */ - struct ip_vs_pe *pe; + struct ip_vs_pe __rcu *pe; + + struct rcu_head rcu_head; }; /* Information for cached dst */ @@ -807,8 +805,6 @@ struct ip_vs_scheduler { int (*init_service)(struct ip_vs_service *svc); /* scheduling service finish */ void (*done_service)(struct ip_vs_service *svc); - /* scheduler updating service */ - int (*update_service)(struct ip_vs_service *svc); /* dest is linked */ int (*add_dest)(struct ip_vs_service *svc, struct ip_vs_dest *dest); /* dest is unlinked */ @@ -1344,8 +1340,6 @@ extern void ip_vs_app_inc_put(struct ip_vs_app *inc); extern int ip_vs_app_pkt_out(struct ip_vs_conn *, struct sk_buff *skb); extern int ip_vs_app_pkt_in(struct ip_vs_conn *, struct sk_buff *skb); -void ip_vs_bind_pe(struct ip_vs_service *svc, struct ip_vs_pe *pe); -void ip_vs_unbind_pe(struct ip_vs_service *svc); int register_ip_vs_pe(struct ip_vs_pe *pe); int unregister_ip_vs_pe(struct ip_vs_pe *pe); struct ip_vs_pe *ip_vs_pe_getbyname(const char *name); @@ -1392,7 +1386,8 @@ extern int register_ip_vs_scheduler(struct ip_vs_scheduler *scheduler); extern int unregister_ip_vs_scheduler(struct ip_vs_scheduler *scheduler); extern int ip_vs_bind_scheduler(struct ip_vs_service *svc, struct ip_vs_scheduler *scheduler); -extern void ip_vs_unbind_scheduler(struct ip_vs_service *svc); +extern void ip_vs_unbind_scheduler(struct ip_vs_service *svc, + struct ip_vs_scheduler *sched); extern struct ip_vs_scheduler *ip_vs_scheduler_get(const char *sched_name); extern void ip_vs_scheduler_put(struct ip_vs_scheduler *scheduler); extern struct ip_vs_conn * @@ -1412,14 +1407,9 @@ extern struct ip_vs_stats ip_vs_stats; extern int sysctl_ip_vs_sync_ver; extern struct ip_vs_service * -ip_vs_service_get(struct net *net, int af, __u32 fwmark, __u16 protocol, +ip_vs_service_find(struct net *net, int af, __u32 fwmark, __u16 protocol, const union nf_inet_addr *vaddr, __be16 vport); -static inline void ip_vs_service_put(struct ip_vs_service *svc) -{ - atomic_dec(&svc->usecnt); -} - extern bool ip_vs_has_real_service(struct net *net, int af, __u16 protocol, const union nf_inet_addr *daddr, __be16 dport); -- cgit v1.1