diff options
Diffstat (limited to 'net/ipv4/inetpeer.c')
-rw-r--r-- | net/ipv4/inetpeer.c | 77 |
1 files changed, 49 insertions, 28 deletions
diff --git a/net/ipv4/inetpeer.c b/net/ipv4/inetpeer.c index d4d61b694fab..cac02ad1425d 100644 --- a/net/ipv4/inetpeer.c +++ b/net/ipv4/inetpeer.c @@ -82,23 +82,39 @@ static const struct inet_peer peer_fake_node = { .avl_height = 0 }; -struct inet_peer_base { - struct inet_peer __rcu *root; - seqlock_t lock; - int total; -}; +void inet_peer_base_init(struct inet_peer_base *bp) +{ + bp->root = peer_avl_empty_rcu; + seqlock_init(&bp->lock); + bp->flush_seq = ~0U; + bp->total = 0; +} +EXPORT_SYMBOL_GPL(inet_peer_base_init); -static struct inet_peer_base v4_peers = { - .root = peer_avl_empty_rcu, - .lock = __SEQLOCK_UNLOCKED(v4_peers.lock), - .total = 0, -}; +static atomic_t v4_seq = ATOMIC_INIT(0); +static atomic_t v6_seq = ATOMIC_INIT(0); -static struct inet_peer_base v6_peers = { - .root = peer_avl_empty_rcu, - .lock = __SEQLOCK_UNLOCKED(v6_peers.lock), - .total = 0, -}; +static atomic_t *inetpeer_seq_ptr(int family) +{ + return (family == AF_INET ? &v4_seq : &v6_seq); +} + +static inline void flush_check(struct inet_peer_base *base, int family) +{ + atomic_t *fp = inetpeer_seq_ptr(family); + + if (unlikely(base->flush_seq != atomic_read(fp))) { + inetpeer_invalidate_tree(base); + base->flush_seq = atomic_read(fp); + } +} + +void inetpeer_invalidate_family(int family) +{ + atomic_t *fp = inetpeer_seq_ptr(family); + + atomic_inc(fp); +} #define PEER_MAXDEPTH 40 /* sufficient for about 2^27 nodes */ @@ -401,11 +417,6 @@ static void unlink_from_pool(struct inet_peer *p, struct inet_peer_base *base, call_rcu(&p->rcu, inetpeer_free_rcu); } -static struct inet_peer_base *family_to_base(int family) -{ - return family == AF_INET ? &v4_peers : &v6_peers; -} - /* perform garbage collect on all items stacked during a lookup */ static int inet_peer_gc(struct inet_peer_base *base, struct inet_peer __rcu **stack[PEER_MAXDEPTH], @@ -443,14 +454,17 @@ static int inet_peer_gc(struct inet_peer_base *base, return cnt; } -struct inet_peer *inet_getpeer(const struct inetpeer_addr *daddr, int create) +struct inet_peer *inet_getpeer(struct inet_peer_base *base, + const struct inetpeer_addr *daddr, + int create) { struct inet_peer __rcu **stack[PEER_MAXDEPTH], ***stackptr; - struct inet_peer_base *base = family_to_base(daddr->family); struct inet_peer *p; unsigned int sequence; int invalidated, gccnt = 0; + flush_check(base, daddr->family); + /* Attempt a lockless lookup first. * Because of a concurrent writer, we might not find an existing entry. */ @@ -560,10 +574,20 @@ bool inet_peer_xrlim_allow(struct inet_peer *peer, int timeout) } EXPORT_SYMBOL(inet_peer_xrlim_allow); -void inetpeer_invalidate_tree(int family) +static void inetpeer_inval_rcu(struct rcu_head *head) +{ + struct inet_peer *p = container_of(head, struct inet_peer, gc_rcu); + + spin_lock_bh(&gc_lock); + list_add_tail(&p->gc_list, &gc_list); + spin_unlock_bh(&gc_lock); + + schedule_delayed_work(&gc_work, gc_delay); +} + +void inetpeer_invalidate_tree(struct inet_peer_base *base) { struct inet_peer *old, *new, *prev; - struct inet_peer_base *base = family_to_base(family); write_seqlock_bh(&base->lock); @@ -576,10 +600,7 @@ void inetpeer_invalidate_tree(int family) prev = cmpxchg(&base->root, old, new); if (prev == old) { base->total = 0; - spin_lock(&gc_lock); - list_add_tail(&prev->gc_list, &gc_list); - spin_unlock(&gc_lock); - schedule_delayed_work(&gc_work, gc_delay); + call_rcu(&prev->gc_rcu, inetpeer_inval_rcu); } out: |