linux/include/net/fib_rules.h
Eric Dumazet ebc0ffae5d fib: RCU conversion of fib_lookup()
fib_lookup() converted to be called in RCU protected context, no
reference taken and released on a contended cache line (fib_clntref)

fib_table_lookup() and fib_semantic_match() get an additional parameter.

struct fib_info gets an rcu_head field, and is freed after an rcu grace
period.

Stress test :
(Sending 160.000.000 UDP frames on same neighbour,
IP route cache disabled, dual E5540 @2.53GHz,
32bit kernel, FIB_HASH) (about same results for FIB_TRIE)

Before patch :

real	1m31.199s
user	0m13.761s
sys	23m24.780s

After patch:

real	1m5.375s
user	0m14.997s
sys	15m50.115s

Before patch Profile :

13044.00 15.4% __ip_route_output_key vmlinux
 8438.00 10.0% dst_destroy           vmlinux
 5983.00  7.1% fib_semantic_match    vmlinux
 5410.00  6.4% fib_rules_lookup      vmlinux
 4803.00  5.7% neigh_lookup          vmlinux
 4420.00  5.2% _raw_spin_lock        vmlinux
 3883.00  4.6% rt_set_nexthop        vmlinux
 3261.00  3.9% _raw_read_lock        vmlinux
 2794.00  3.3% fib_table_lookup      vmlinux
 2374.00  2.8% neigh_resolve_output  vmlinux
 2153.00  2.5% dst_alloc             vmlinux
 1502.00  1.8% _raw_read_lock_bh     vmlinux
 1484.00  1.8% kmem_cache_alloc      vmlinux
 1407.00  1.7% eth_header            vmlinux
 1406.00  1.7% ipv4_dst_destroy      vmlinux
 1298.00  1.5% __copy_from_user_ll   vmlinux
 1174.00  1.4% dev_queue_xmit        vmlinux
 1000.00  1.2% ip_output             vmlinux

After patch Profile :

13712.00 15.8% dst_destroy             vmlinux
 8548.00  9.9% __ip_route_output_key   vmlinux
 7017.00  8.1% neigh_lookup            vmlinux
 4554.00  5.3% fib_semantic_match      vmlinux
 4067.00  4.7% _raw_read_lock          vmlinux
 3491.00  4.0% dst_alloc               vmlinux
 3186.00  3.7% neigh_resolve_output    vmlinux
 3103.00  3.6% fib_table_lookup        vmlinux
 2098.00  2.4% _raw_read_lock_bh       vmlinux
 2081.00  2.4% kmem_cache_alloc        vmlinux
 2013.00  2.3% _raw_spin_lock          vmlinux
 1763.00  2.0% __copy_from_user_ll     vmlinux
 1763.00  2.0% ip_output               vmlinux
 1761.00  2.0% ipv4_dst_destroy        vmlinux
 1631.00  1.9% eth_header              vmlinux
 1440.00  1.7% _raw_read_unlock_bh     vmlinux

Reference results, if IP route cache is enabled :

real	0m29.718s
user	0m10.845s
sys	7m37.341s

25213.00 29.5% __ip_route_output_key   vmlinux
 9011.00 10.5% dst_release             vmlinux
 4817.00  5.6% ip_push_pending_frames  vmlinux
 4232.00  5.0% ip_finish_output        vmlinux
 3940.00  4.6% udp_sendmsg             vmlinux
 3730.00  4.4% __copy_from_user_ll     vmlinux
 3716.00  4.4% ip_route_output_flow    vmlinux
 2451.00  2.9% __xfrm_lookup           vmlinux
 2221.00  2.6% ip_append_data          vmlinux
 1718.00  2.0% _raw_spin_lock_bh       vmlinux
 1655.00  1.9% __alloc_skb             vmlinux
 1572.00  1.8% sock_wfree              vmlinux
 1345.00  1.6% kfree                   vmlinux

Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2010-10-05 20:39:38 -07:00

120 lines
3.0 KiB
C

#ifndef __NET_FIB_RULES_H
#define __NET_FIB_RULES_H
#include <linux/types.h>
#include <linux/slab.h>
#include <linux/netdevice.h>
#include <linux/fib_rules.h>
#include <net/flow.h>
#include <net/rtnetlink.h>
struct fib_rule {
struct list_head list;
atomic_t refcnt;
int iifindex;
int oifindex;
u32 mark;
u32 mark_mask;
u32 pref;
u32 flags;
u32 table;
u8 action;
u32 target;
struct fib_rule * ctarget;
char iifname[IFNAMSIZ];
char oifname[IFNAMSIZ];
struct rcu_head rcu;
struct net * fr_net;
};
struct fib_lookup_arg {
void *lookup_ptr;
void *result;
struct fib_rule *rule;
int flags;
#define FIB_LOOKUP_NOREF 1
};
struct fib_rules_ops {
int family;
struct list_head list;
int rule_size;
int addr_size;
int unresolved_rules;
int nr_goto_rules;
int (*action)(struct fib_rule *,
struct flowi *, int,
struct fib_lookup_arg *);
int (*match)(struct fib_rule *,
struct flowi *, int);
int (*configure)(struct fib_rule *,
struct sk_buff *,
struct fib_rule_hdr *,
struct nlattr **);
int (*compare)(struct fib_rule *,
struct fib_rule_hdr *,
struct nlattr **);
int (*fill)(struct fib_rule *, struct sk_buff *,
struct fib_rule_hdr *);
u32 (*default_pref)(struct fib_rules_ops *ops);
size_t (*nlmsg_payload)(struct fib_rule *);
/* Called after modifications to the rules set, must flush
* the route cache if one exists. */
void (*flush_cache)(struct fib_rules_ops *ops);
int nlgroup;
const struct nla_policy *policy;
struct list_head rules_list;
struct module *owner;
struct net *fro_net;
struct rcu_head rcu;
};
#define FRA_GENERIC_POLICY \
[FRA_IIFNAME] = { .type = NLA_STRING, .len = IFNAMSIZ - 1 }, \
[FRA_OIFNAME] = { .type = NLA_STRING, .len = IFNAMSIZ - 1 }, \
[FRA_PRIORITY] = { .type = NLA_U32 }, \
[FRA_FWMARK] = { .type = NLA_U32 }, \
[FRA_FWMASK] = { .type = NLA_U32 }, \
[FRA_TABLE] = { .type = NLA_U32 }, \
[FRA_GOTO] = { .type = NLA_U32 }
static inline void fib_rule_get(struct fib_rule *rule)
{
atomic_inc(&rule->refcnt);
}
static inline void fib_rule_put_rcu(struct rcu_head *head)
{
struct fib_rule *rule = container_of(head, struct fib_rule, rcu);
release_net(rule->fr_net);
kfree(rule);
}
static inline void fib_rule_put(struct fib_rule *rule)
{
if (atomic_dec_and_test(&rule->refcnt))
call_rcu(&rule->rcu, fib_rule_put_rcu);
}
static inline u32 frh_get_table(struct fib_rule_hdr *frh, struct nlattr **nla)
{
if (nla[FRA_TABLE])
return nla_get_u32(nla[FRA_TABLE]);
return frh->table;
}
extern struct fib_rules_ops *fib_rules_register(const struct fib_rules_ops *, struct net *);
extern void fib_rules_unregister(struct fib_rules_ops *);
extern int fib_rules_lookup(struct fib_rules_ops *,
struct flowi *, int flags,
struct fib_lookup_arg *);
extern int fib_default_rule_add(struct fib_rules_ops *,
u32 pref, u32 table,
u32 flags);
extern u32 fib_default_rule_pref(struct fib_rules_ops *ops);
#endif