summaryrefslogtreecommitdiffstats
path: root/include/net/tcp.h
diff options
context:
space:
mode:
authorEric Dumazet <edumazet@google.com>2019-10-10 20:17:41 -0700
committerDavid S. Miller <davem@davemloft.net>2019-10-13 10:13:08 -0700
commit0f31746452e6793ad6271337438af8f4defb8940 (patch)
treeb30e39e3839addc642ceb8c87ce5e20be2c79fae /include/net/tcp.h
parent7db48e983930285b765743ebd665aecf9850582b (diff)
downloadlinux-0f31746452e6793ad6271337438af8f4defb8940.tar.bz2
tcp: annotate tp->write_seq lockless reads
There are few places where we fetch tp->write_seq while this field can change from IRQ or other cpu. We need to add READ_ONCE() annotations, and also make sure write sides use corresponding WRITE_ONCE() to avoid store-tearing. Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'include/net/tcp.h')
-rw-r--r--include/net/tcp.h2
1 files changed, 1 insertions, 1 deletions
diff --git a/include/net/tcp.h b/include/net/tcp.h
index 35f6f7e0fdc2..8e7c3f6801a9 100644
--- a/include/net/tcp.h
+++ b/include/net/tcp.h
@@ -1917,7 +1917,7 @@ static inline u32 tcp_notsent_lowat(const struct tcp_sock *tp)
static inline bool tcp_stream_memory_free(const struct sock *sk, int wake)
{
const struct tcp_sock *tp = tcp_sk(sk);
- u32 notsent_bytes = tp->write_seq - tp->snd_nxt;
+ u32 notsent_bytes = READ_ONCE(tp->write_seq) - tp->snd_nxt;
return (notsent_bytes << wake) < tcp_notsent_lowat(tp);
}