diff options
| author | Eric Dumazet <edumazet@google.com> | 2024-10-09 18:44:01 +0000 |
|---|---|---|
| committer | Jakub Kicinski <kuba@kernel.org> | 2024-10-11 15:35:05 -0700 |
| commit | a716ff52bebfe806fbcf5227cee4c7bda4e6724b (patch) | |
| tree | 4f920860cbc8091b53dee41009490791a29598fc /net/core/fib_rules.c | |
| parent | d677aebd663ddc287f2b2bda098474694a0ca875 (diff) | |
fib: rules: use READ_ONCE()/WRITE_ONCE() on ops->fib_rules_seq
Using RTNL to protect ops->fib_rules_seq reads seems a big hammer.
Writes are protected by RTNL.
We can use READ_ONCE() on readers.
Constify 'struct net' argument of fib_rules_seq_read()
and lookup_rules_ops().
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reviewed-by: Kuniyuki Iwashima <kuniyu@amazon.com>
Reviewed-by: David Ahern <dsahern@kernel.org>
Link: https://patch.msgid.link/20241009184405.3752829-2-edumazet@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Diffstat (limited to 'net/core/fib_rules.c')
| -rw-r--r-- | net/core/fib_rules.c | 14 |
1 files changed, 8 insertions, 6 deletions
diff --git a/net/core/fib_rules.c b/net/core/fib_rules.c index 154a2681f55c..82ef090c0037 100644 --- a/net/core/fib_rules.c +++ b/net/core/fib_rules.c @@ -101,7 +101,8 @@ static void notify_rule_change(int event, struct fib_rule *rule, struct fib_rules_ops *ops, struct nlmsghdr *nlh, u32 pid); -static struct fib_rules_ops *lookup_rules_ops(struct net *net, int family) +static struct fib_rules_ops *lookup_rules_ops(const struct net *net, + int family) { struct fib_rules_ops *ops; @@ -370,7 +371,9 @@ static int call_fib_rule_notifiers(struct net *net, .rule = rule, }; - ops->fib_rules_seq++; + ASSERT_RTNL(); + /* Paired with READ_ONCE() in fib_rules_seq() */ + WRITE_ONCE(ops->fib_rules_seq, ops->fib_rules_seq + 1); return call_fib_notifiers(net, event_type, &info.info); } @@ -397,17 +400,16 @@ int fib_rules_dump(struct net *net, struct notifier_block *nb, int family, } EXPORT_SYMBOL_GPL(fib_rules_dump); -unsigned int fib_rules_seq_read(struct net *net, int family) +unsigned int fib_rules_seq_read(const struct net *net, int family) { unsigned int fib_rules_seq; struct fib_rules_ops *ops; - ASSERT_RTNL(); - ops = lookup_rules_ops(net, family); if (!ops) return 0; - fib_rules_seq = ops->fib_rules_seq; + /* Paired with WRITE_ONCE() in call_fib_rule_notifiers() */ + fib_rules_seq = READ_ONCE(ops->fib_rules_seq); rules_ops_put(ops); return fib_rules_seq; |