diff options
| author | Eric Dumazet <edumazet@google.com> | 2019-12-16 18:51:03 -0800 |
|---|---|---|
| committer | David S. Miller <davem@davemloft.net> | 2019-12-17 22:09:52 -0800 |
| commit | 7c68fa2bddda6d942bd387c9ba5b4300737fd991 (patch) | |
| tree | 3e77528920733f3ed1238495a95c87f9f5d59ac9 /include | |
| parent | cad46039e4c99812db067c8ac22a864960e7acc4 (diff) | |
net: annotate lockless accesses to sk->sk_pacing_shift
sk->sk_pacing_shift can be read and written without lock
synchronization. This patch adds annotations to
document this fact and avoid future syzbot complains.
This might also avoid unexpected false sharing
in sk_pacing_shift_update(), as the compiler
could remove the conditional check and always
write over sk->sk_pacing_shift :
if (sk->sk_pacing_shift != val)
sk->sk_pacing_shift = val;
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'include')
| -rw-r--r-- | include/net/sock.h | 4 |
1 files changed, 2 insertions, 2 deletions
diff --git a/include/net/sock.h b/include/net/sock.h index 04c274a20620..22be668457bf 100644 --- a/include/net/sock.h +++ b/include/net/sock.h @@ -2588,9 +2588,9 @@ static inline int sk_get_rmem0(const struct sock *sk, const struct proto *proto) */ static inline void sk_pacing_shift_update(struct sock *sk, int val) { - if (!sk || !sk_fullsock(sk) || sk->sk_pacing_shift == val) + if (!sk || !sk_fullsock(sk) || READ_ONCE(sk->sk_pacing_shift) == val) return; - sk->sk_pacing_shift = val; + WRITE_ONCE(sk->sk_pacing_shift, val); } /* if a socket is bound to a device, check that the given device |