diff options
author | Ido Schimmel <idosch@mellanox.com> | 2016-12-03 16:45:06 +0100 |
---|---|---|
committer | David S. Miller <davem@davemloft.net> | 2016-12-03 19:29:35 -0500 |
commit | cacaad11f43aefbbe5fca00af3b9c16e6aee1ba4 (patch) | |
tree | ca7600f9e865f6bfef8ce60a9c1d1ddd34acba96 /net/ipv4 | |
parent | d3f706f68e2fd93f1172fe7fd6f16ba70cc52b31 (diff) | |
download | op-kernel-dev-cacaad11f43aefbbe5fca00af3b9c16e6aee1ba4.zip op-kernel-dev-cacaad11f43aefbbe5fca00af3b9c16e6aee1ba4.tar.gz |
ipv4: fib: Allow for consistent FIB dumping
The next patch will enable listeners of the FIB notification chain to
request a dump of the FIB tables. However, since RTNL isn't taken during
the dump, it's possible for the FIB tables to change mid-dump, which
will result in inconsistency between the listener's table and the
kernel's.
Allow listeners to know about changes that occurred mid-dump, by adding
a change sequence counter to each net namespace. The counter is
incremented just before a notification is sent in the FIB chain.
Signed-off-by: Ido Schimmel <idosch@mellanox.com>
Signed-off-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'net/ipv4')
-rw-r--r-- | net/ipv4/fib_frontend.c | 2 | ||||
-rw-r--r-- | net/ipv4/fib_trie.c | 1 |
2 files changed, 3 insertions, 0 deletions
diff --git a/net/ipv4/fib_frontend.c b/net/ipv4/fib_frontend.c index 121384b..dbad5a1 100644 --- a/net/ipv4/fib_frontend.c +++ b/net/ipv4/fib_frontend.c @@ -1219,6 +1219,8 @@ static int __net_init ip_fib_net_init(struct net *net) int err; size_t size = sizeof(struct hlist_head) * FIB_TABLE_HASHSZ; + net->ipv4.fib_seq = 0; + /* Avoid false sharing : Use at least a full cache line */ size = max_t(size_t, size, L1_CACHE_BYTES); diff --git a/net/ipv4/fib_trie.c b/net/ipv4/fib_trie.c index 9bfce0d..2891356 100644 --- a/net/ipv4/fib_trie.c +++ b/net/ipv4/fib_trie.c @@ -101,6 +101,7 @@ EXPORT_SYMBOL(unregister_fib_notifier); int call_fib_notifiers(struct net *net, enum fib_event_type event_type, struct fib_notifier_info *info) { + net->ipv4.fib_seq++; info->net = net; return atomic_notifier_call_chain(&fib_chain, event_type, info); } |