diff options
author | Kui-Feng Lee <thinker.li@gmail.com> | 2024-02-09 01:06:51 +0300 |
---|---|---|
committer | David S. Miller <davem@davemloft.net> | 2024-02-12 13:24:12 +0300 |
commit | 5eb902b8e7193cdcb33242af0a56502e6b5206e9 (patch) | |
tree | 8aaad37743b6698aa51eca28b8021c012a04f552 /include/net/ip6_fib.h | |
parent | 60df43d3a72c5fc50ff854cca17c9935c4398794 (diff) | |
download | linux-5eb902b8e7193cdcb33242af0a56502e6b5206e9.tar.xz |
net/ipv6: Remove expired routes with a separated list of routes.
FIB6 GC walks trees of fib6_tables to remove expired routes. Walking a tree
can be expensive if the number of routes in a table is big, even if most of
them are permanent. Checking routes in a separated list of routes having
expiration will avoid this potential issue.
Reviewed-by: David Ahern <dsahern@kernel.org>
Signed-off-by: Kui-Feng Lee <thinker.li@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'include/net/ip6_fib.h')
-rw-r--r-- | include/net/ip6_fib.h | 46 |
1 files changed, 45 insertions, 1 deletions
diff --git a/include/net/ip6_fib.h b/include/net/ip6_fib.h index 360b12e61850..323c94f1845b 100644 --- a/include/net/ip6_fib.h +++ b/include/net/ip6_fib.h @@ -173,6 +173,9 @@ struct fib6_info { refcount_t fib6_ref; unsigned long expires; + + struct hlist_node gc_link; + struct dst_metrics *fib6_metrics; #define fib6_pmtu fib6_metrics->metrics[RTAX_MTU-1] @@ -241,12 +244,18 @@ static inline bool fib6_requires_src(const struct fib6_info *rt) return rt->fib6_src.plen > 0; } +/* The callers should hold f6i->fib6_table->tb6_lock if a route has ever + * been added to a table before. + */ static inline void fib6_clean_expires(struct fib6_info *f6i) { f6i->fib6_flags &= ~RTF_EXPIRES; f6i->expires = 0; } +/* The callers should hold f6i->fib6_table->tb6_lock if a route has ever + * been added to a table before. + */ static inline void fib6_set_expires(struct fib6_info *f6i, unsigned long expires) { @@ -327,8 +336,10 @@ static inline bool fib6_info_hold_safe(struct fib6_info *f6i) static inline void fib6_info_release(struct fib6_info *f6i) { - if (f6i && refcount_dec_and_test(&f6i->fib6_ref)) + if (f6i && refcount_dec_and_test(&f6i->fib6_ref)) { + DEBUG_NET_WARN_ON_ONCE(!hlist_unhashed(&f6i->gc_link)); call_rcu(&f6i->rcu, fib6_info_destroy_rcu); + } } enum fib6_walk_state { @@ -382,6 +393,7 @@ struct fib6_table { struct inet_peer_base tb6_peers; unsigned int flags; unsigned int fib_seq; + struct hlist_head tb6_gc_hlist; /* GC candidates */ #define RT6_TABLE_HAS_DFLT_ROUTER BIT(0) }; @@ -498,6 +510,38 @@ void fib6_gc_cleanup(void); int fib6_init(void); +/* Add the route to the gc list if it is not already there + * + * The callers should hold f6i->fib6_table->tb6_lock. + */ +static inline void fib6_add_gc_list(struct fib6_info *f6i) +{ + /* If fib6_node is null, the f6i is not in (or removed from) the + * table. + * + * There is a gap between finding the f6i from the table and + * calling this function without the protection of the tb6_lock. + * This check makes sure the f6i is not added to the gc list when + * it is not on the table. + */ + if (!rcu_dereference_protected(f6i->fib6_node, + lockdep_is_held(&f6i->fib6_table->tb6_lock))) + return; + + if (hlist_unhashed(&f6i->gc_link)) + hlist_add_head(&f6i->gc_link, &f6i->fib6_table->tb6_gc_hlist); +} + +/* Remove the route from the gc list if it is on the list. + * + * The callers should hold f6i->fib6_table->tb6_lock. + */ +static inline void fib6_remove_gc_list(struct fib6_info *f6i) +{ + if (!hlist_unhashed(&f6i->gc_link)) + hlist_del_init(&f6i->gc_link); +} + struct ipv6_route_iter { struct seq_net_private p; struct fib6_walker w; |