bird/sysdep/unix/krt.h
Ondrej Zajicek 534d0a4b44 KRT: Scan routing tables separetely on linux to avoid congestion
Remove compile-time sysdep option CONFIG_ALL_TABLES_AT_ONCE, replace it
with runtime ability to run either separate table scans or shared scan.

On Linux, use separate table scans by default when the netlink socket
option NETLINK_GET_STRICT_CHK is available, but retreat to shared scan
when it fails.

Running separate table scans has advantages where some routing tables are
managed independently, e.g. when multiple routing daemons are running on
the same machine, as kernel routing table modification performance is
significantly reduced when the table is modified while it is being
scanned.

Thanks Daniel Gröber for the original patch and Toke Høiland-Jørgensen
for suggestions.
2022-07-24 02:15:20 +02:00

159 lines
4.4 KiB
C

/*
* BIRD -- UNIX Kernel Route Syncer
*
* (c) 1998--2000 Martin Mares <mj@ucw.cz>
*
* Can be freely distributed and used under the terms of the GNU GPL.
*/
#ifndef _BIRD_KRT_H_
#define _BIRD_KRT_H_
struct config;
struct krt_config;
struct krt_proto;
struct kif_config;
struct kif_proto;
#include "nest/iface.h"
#include "sysdep/config.h"
#include CONFIG_INCLUDE_KRTSYS_H
#define KRT_DEFAULT_ECMP_LIMIT 16
#define EA_KRT_SOURCE EA_CODE(PROTOCOL_KERNEL, 0)
#define EA_KRT_METRIC EA_CODE(PROTOCOL_KERNEL, 1)
/* Whenever we recognize our own routes, we allow learing of foreign routes */
#ifdef CONFIG_SELF_CONSCIOUS
#define KRT_ALLOW_LEARN
#endif
/* krt.c */
extern struct protocol proto_unix_kernel;
struct krt_config {
struct proto_config c;
struct krt_params sys; /* Sysdep params */
btime scan_time; /* How often we re-scan routes */
int persist; /* Keep routes when we exit */
int learn; /* Learn routes from other sources */
int graceful_restart; /* Regard graceful restart recovery */
int merge_paths; /* Exported routes are merged for ECMP */
};
struct krt_proto {
struct proto p;
struct krt_state sys; /* Sysdep state */
#ifdef KRT_ALLOW_LEARN
struct rtable *krt_table; /* Internal table of inherited routes */
#endif
timer *scan_timer;
struct bmap sync_map; /* Keeps track which exported routes were successfully written to kernel */
struct bmap seen_map; /* Routes seen during last periodic scan */
node krt_node; /* Node in krt_proto_list */
byte af; /* Kernel address family (AF_*) */
byte ready; /* Initial feed has been finished */
byte initialized; /* First scan has been finished */
byte reload; /* Next scan is doing reload */
};
extern pool *krt_pool;
#define KRT_CF ((struct krt_config *)p->p.cf)
#define KRT_TRACE(pr, fl, msg, args...) do { \
DBG("KRT: " msg "\n" , ## args); \
if (pr->p.debug & fl) \
{ log(L_TRACE "%s: " msg, pr->p.name , ## args); } } while(0)
struct proto_config * kif_init_config(int class);
void kif_request_scan(void);
void krt_use_shared_scan(void);
void krt_got_route(struct krt_proto *p, struct rte *e);
void krt_got_route_async(struct krt_proto *p, struct rte *e, int new);
static inline int
krt_get_sync_error(struct krt_proto *p, struct rte *e)
{
return (p->p.proto_state == PS_UP) &&
bmap_test(&p->p.main_channel->export_map, e->id) &&
!bmap_test(&p->sync_map, e->id);
}
/* Values for rte->u.krt_sync.src */
#define KRT_SRC_UNKNOWN -1 /* Nobody knows */
#define KRT_SRC_BIRD 0 /* Our route (not passed in async mode) */
#define KRT_SRC_REDIRECT 1 /* Redirect route, delete it */
#define KRT_SRC_ALIEN 2 /* Route installed by someone else */
#define KRT_SRC_KERNEL 3 /* Kernel routes, are ignored by krt syncer */
extern struct protocol proto_unix_iface;
struct kif_config {
struct proto_config c;
struct kif_params sys; /* Sysdep params */
list iface_list; /* List of iface configs (struct kif_iface_config) */
btime scan_time; /* How often we re-scan interfaces */
};
struct kif_iface_config {
struct iface_patt i;
ip_addr pref_v4;
ip_addr pref_v6;
ip_addr pref_ll;
};
struct kif_proto {
struct proto p;
struct kif_state sys; /* Sysdep state */
};
extern struct kif_proto *kif_proto;
#define KIF_CF ((struct kif_config *)p->p.cf)
struct kif_iface_config * kif_get_iface_config(struct iface *iface);
struct proto_config * krt_init_config(int class);
/* krt sysdep */
void krt_sys_io_init(void);
void krt_sys_init(struct krt_proto *);
int krt_sys_start(struct krt_proto *);
void krt_sys_shutdown(struct krt_proto *);
int krt_sys_reconfigure(struct krt_proto *p UNUSED, struct krt_config *n, struct krt_config *o);
void krt_sys_preconfig(struct config *);
void krt_sys_postconfig(struct krt_config *);
void krt_sys_init_config(struct krt_config *);
void krt_sys_copy_config(struct krt_config *, struct krt_config *);
int krt_capable(rte *e);
void krt_do_scan(struct krt_proto *);
void krt_replace_rte(struct krt_proto *p, net *n, rte *new, rte *old);
int krt_sys_get_attr(const eattr *a, byte *buf, int buflen);
/* kif sysdep */
void kif_sys_init(struct kif_proto *);
void kif_sys_start(struct kif_proto *);
void kif_sys_shutdown(struct kif_proto *);
int kif_sys_reconfigure(struct kif_proto *, struct kif_config *, struct kif_config *);
void kif_sys_init_config(struct kif_config *);
void kif_sys_copy_config(struct kif_config *, struct kif_config *);
void kif_do_scan(struct kif_proto *);
int kif_update_sysdep_addr(struct iface *i);
#endif