path: root/include/net/sock.h
diff options
authorEric Dumazet <edumazet@google.com>2019-12-16 18:51:03 -0800
committerDavid S. Miller <davem@davemloft.net>2019-12-17 22:09:52 -0800
commit7c68fa2bddda6d942bd387c9ba5b4300737fd991 (patch)
tree3e77528920733f3ed1238495a95c87f9f5d59ac9 /include/net/sock.h
parentnet: qlogic: Fix error paths in ql_alloc_large_buffers() (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/net/sock.h')
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)
- 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