diff options
| author | Eric Dumazet <edumazet@google.com> | 2023-09-22 03:42:15 +0000 |
|---|---|---|
| committer | David S. Miller <davem@davemloft.net> | 2023-10-01 19:39:18 +0100 |
| commit | ceaa714138a372ac63cc2c5c19ee0882d22827f9 (patch) | |
| tree | 73b347539e9039e35d9ef9566cf38ec5e6cfb214 /include/net/ip.h | |
| parent | c9746e6a19c24b2d9a74d6657daee3b39fdc1bec (diff) | |
inet: implement lockless IP_MTU_DISCOVER
inet->pmtudisc can be read locklessly.
Implement proper lockless reads and writes to inet->pmtudisc
ip_sock_set_mtu_discover() can now be called from arbitrary
contexts.
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reviewed-by: David Ahern <dsahern@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'include/net/ip.h')
| -rw-r--r-- | include/net/ip.h | 13 |
1 files changed, 8 insertions, 5 deletions
diff --git a/include/net/ip.h b/include/net/ip.h index 3489a1cca5e7..46933a0d98ea 100644 --- a/include/net/ip.h +++ b/include/net/ip.h @@ -434,19 +434,22 @@ int ip_dont_fragment(const struct sock *sk, const struct dst_entry *dst) static inline bool ip_sk_accept_pmtu(const struct sock *sk) { - return inet_sk(sk)->pmtudisc != IP_PMTUDISC_INTERFACE && - inet_sk(sk)->pmtudisc != IP_PMTUDISC_OMIT; + u8 pmtudisc = READ_ONCE(inet_sk(sk)->pmtudisc); + + return pmtudisc != IP_PMTUDISC_INTERFACE && + pmtudisc != IP_PMTUDISC_OMIT; } static inline bool ip_sk_use_pmtu(const struct sock *sk) { - return inet_sk(sk)->pmtudisc < IP_PMTUDISC_PROBE; + return READ_ONCE(inet_sk(sk)->pmtudisc) < IP_PMTUDISC_PROBE; } static inline bool ip_sk_ignore_df(const struct sock *sk) { - return inet_sk(sk)->pmtudisc < IP_PMTUDISC_DO || - inet_sk(sk)->pmtudisc == IP_PMTUDISC_OMIT; + u8 pmtudisc = READ_ONCE(inet_sk(sk)->pmtudisc); + + return pmtudisc < IP_PMTUDISC_DO || pmtudisc == IP_PMTUDISC_OMIT; } static inline unsigned int ip_dst_mtu_maybe_forward(const struct dst_entry *dst, |