diff options
| -rw-r--r-- | nest/route.h | 10 | ||||
| -rw-r--r-- | nest/rt-attr.c | 29 |
2 files changed, 30 insertions, 9 deletions
diff --git a/nest/route.h b/nest/route.h index a01eff1a..b327e42a 100644 --- a/nest/route.h +++ b/nest/route.h @@ -590,7 +590,7 @@ struct rte_src { typedef struct rta { struct rta *next, **pprev; /* Hash chain */ - u32 uc; /* Use count */ + _Atomic u32 uc; /* Use count */ u32 hash_key; /* Hash over important fields */ struct ea_list *eattrs; /* Extended Attribute chain */ struct hostentry *hostentry; /* Hostentry for recursive next-hops */ @@ -862,15 +862,15 @@ static inline size_t rta_size(const rta *a) { return sizeof(rta) + sizeof(u32)*a #define RTA_MAX_SIZE (sizeof(rta) + sizeof(u32)*MPLS_MAX_LABEL_STACK) rta *rta_lookup(rta *); /* Get rta equivalent to this one, uc++ */ static inline int rta_is_cached(rta *r) { return r->cached; } -static inline rta *rta_clone(rta *r) { r->uc++; return r; } +static inline rta *rta_clone(rta *r) { ASSERT_DIE(0 < atomic_fetch_add_explicit(&r->uc, 1, memory_order_acq_rel)); return r; } void rta__free(rta *r); -static inline void rta_free(rta *r) { if (r && !--r->uc) rta__free(r); } +static inline void rta_free(rta *r) { if (r && (1 == atomic_fetch_sub_explicit(&r->uc, 1, memory_order_acq_rel))) rta__free(r); } rta *rta_do_cow(rta *o, linpool *lp); static inline rta * rta_cow(rta *r, linpool *lp) { return rta_is_cached(r) ? rta_do_cow(r, lp) : r; } static inline void rta_uncache(rta *r) { r->cached = 0; r->uc = 0; } -void rta_dump(rta *); +void rta_dump(const rta *); void rta_dump_all(void); -void rta_show(struct cli *, rta *); +void rta_show(struct cli *, const rta *); u32 rt_get_igp_metric(rte *); struct hostentry * rt_get_hostentry(rtable *tab, ip_addr a, ip_addr ll, rtable *dep); diff --git a/nest/rt-attr.c b/nest/rt-attr.c index f7e33d72..20f9835d 100644 --- a/nest/rt-attr.c +++ b/nest/rt-attr.c @@ -1281,9 +1281,16 @@ rta_lookup(rta *o) ea_normalize(o->eattrs); h = rta_hash(o); + + RTA_LOCK; + for(r=rta_hash_table[h & rta_cache_mask]; r; r=r->next) if (r->hash_key == h && rta_same(r, o)) - return rta_clone(r); + { + atomic_fetch_add_explicit(&r->uc, 1, memory_order_acq_rel); + RTA_UNLOCK; + return r; + } r = rta_copy(o); r->hash_key = h; @@ -1294,12 +1301,21 @@ rta_lookup(rta *o) if (++rta_cache_count > rta_cache_limit) rta_rehash(); + RTA_UNLOCK; return r; } void rta__free(rta *a) { + RTA_LOCK; + if (atomic_load_explicit(&a->uc, memory_order_acquire)) + { + /* Somebody has cloned this rta inbetween. This sometimes happens. */ + RTA_UNLOCK; + return; + } + ASSERT(rta_cache_count && a->cached); rta_cache_count--; *a->pprev = a->next; @@ -1311,6 +1327,7 @@ rta__free(rta *a) ea_free(a->eattrs); a->cached = 0; sl_free(rta_slab(a), a); + RTA_UNLOCK; } rta * @@ -1335,7 +1352,7 @@ rta_do_cow(rta *o, linpool *lp) * This function takes a &rta and dumps its contents to the debug output. */ void -rta_dump(rta *a) +rta_dump(const rta *a) { static char *rts[] = { "", "RTS_STATIC", "RTS_INHERIT", "RTS_DEVICE", "RTS_STAT_DEV", "RTS_REDIR", "RTS_RIP", @@ -1350,7 +1367,7 @@ rta_dump(rta *a) debug(" !CACHED"); debug(" <-%I", a->from); if (a->dest == RTD_UNICAST) - for (struct nexthop *nh = &(a->nh); nh; nh = nh->next) + for (const struct nexthop *nh = &(a->nh); nh; nh = nh->next) { if (ipa_nonzero(nh->gw)) debug(" ->%I", nh->gw); if (nh->labels) debug(" L %d", nh->label[0]); @@ -1377,6 +1394,8 @@ rta_dump_all(void) rta *a; uint h; + RTA_LOCK; + debug("Route attribute cache (%d entries, rehash at %d):\n", rta_cache_count, rta_cache_limit); for(h=0; h<rta_cache_size; h++) for(a=rta_hash_table[h]; a; a=a->next) @@ -1386,10 +1405,12 @@ rta_dump_all(void) debug("\n"); } debug("\n"); + + RTA_UNLOCK; } void -rta_show(struct cli *c, rta *a) +rta_show(struct cli *c, const rta *a) { cli_printf(c, -1008, "\tType: %s %s", rta_src_names[a->source], ip_scope_text(a->scope)); |