tcp: annotate tp->copied_seq lockless reads

There are few places where we fetch tp->copied_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.

Note that tcp_inq_hint() was already using READ_ONCE(tp->copied_seq)

Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
Eric Dumazet
2019-10-10 20:17:40 -07:00
committed by David S. Miller
parent dba7d9b8c7
commit 7db48e9839
7 changed files with 19 additions and 18 deletions

View File

@@ -1896,7 +1896,7 @@ static void get_tcp6_sock(struct seq_file *seq, struct sock *sp, int i)
* we might find a transient negative value.
*/
rx_queue = max_t(int, READ_ONCE(tp->rcv_nxt) -
tp->copied_seq, 0);
READ_ONCE(tp->copied_seq), 0);
seq_printf(seq,
"%4d: %08X%08X%08X%08X:%04X %08X%08X%08X%08X:%04X "