tcp: fix lockdep splat in tcp_snd_una_update()
tcp_snd_una_update() and tcp_rcv_nxt_update() call
u64_stats_update_begin() either from process context or BH handler.
This triggers a lockdep splat on 32bit & SMP builds.
We could add u64_stats_update_begin_bh() variant but this would
slow down 32bit builds with useless local_disable_bh() and
local_enable_bh() pairs, since we own the socket lock at this point.
I add sock_owned_by_me() helper to have proper lockdep support
even on 64bit builds, and new u64_stats_update_begin_raw()
and u64_stats_update_end_raw methods.
Fixes: c10d9310edf5 ("tcp: do not assume TCP code is non preemptible")
Reported-by: Fabio Estevam <[email protected]>
Diagnosed-by: Francois Romieu <[email protected]>
Signed-off-by: Eric Dumazet <[email protected]>
Tested-by: Fabio Estevam <[email protected]>
Signed-off-by: David S. Miller <[email protected]>
diff --git a/include/net/sock.h b/include/net/sock.h
index 45f5b49..c9c8b19 100644
--- a/include/net/sock.h
+++ b/include/net/sock.h
@@ -1421,11 +1421,16 @@
* accesses from user process context.
*/
-static inline bool sock_owned_by_user(const struct sock *sk)
+static inline void sock_owned_by_me(const struct sock *sk)
{
#ifdef CONFIG_LOCKDEP
WARN_ON_ONCE(!lockdep_sock_is_held(sk) && debug_locks);
#endif
+}
+
+static inline bool sock_owned_by_user(const struct sock *sk)
+{
+ sock_owned_by_me(sk);
return sk->sk_lock.owned;
}
