tcp: do not block bh during prequeue processing
AFAIK, nothing in current TCP stack absolutely wants BH
being disabled once socket is owned by a thread running in
process context.
As mentioned in my prior patch ("tcp: give prequeue mode some care"),
processing a batch of packets might take time, better not block BH
at all.
Signed-off-by: Eric Dumazet <edumazet@google.com>
Acked-by: Soheil Hassas Yeganeh <soheil@google.com>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/ipv4/tcp_input.c b/net/ipv4/tcp_input.c
index ac85fb4..6171f92 100644
--- a/net/ipv4/tcp_input.c
+++ b/net/ipv4/tcp_input.c
@@ -4611,14 +4611,12 @@
__set_current_state(TASK_RUNNING);
- local_bh_enable();
if (!skb_copy_datagram_msg(skb, 0, tp->ucopy.msg, chunk)) {
tp->ucopy.len -= chunk;
tp->copied_seq += chunk;
eaten = (chunk == skb->len);
tcp_rcv_space_adjust(sk);
}
- local_bh_disable();
}
if (eaten <= 0) {
@@ -5134,7 +5132,6 @@
int chunk = skb->len - hlen;
int err;
- local_bh_enable();
if (skb_csum_unnecessary(skb))
err = skb_copy_datagram_msg(skb, hlen, tp->ucopy.msg, chunk);
else
@@ -5146,32 +5143,9 @@
tcp_rcv_space_adjust(sk);
}
- local_bh_disable();
return err;
}
-static __sum16 __tcp_checksum_complete_user(struct sock *sk,
- struct sk_buff *skb)
-{
- __sum16 result;
-
- if (sock_owned_by_user(sk)) {
- local_bh_enable();
- result = __tcp_checksum_complete(skb);
- local_bh_disable();
- } else {
- result = __tcp_checksum_complete(skb);
- }
- return result;
-}
-
-static inline bool tcp_checksum_complete_user(struct sock *sk,
- struct sk_buff *skb)
-{
- return !skb_csum_unnecessary(skb) &&
- __tcp_checksum_complete_user(sk, skb);
-}
-
/* Does PAWS and seqno based validation of an incoming segment, flags will
* play significant role here.
*/
@@ -5386,7 +5360,7 @@
}
}
if (!eaten) {
- if (tcp_checksum_complete_user(sk, skb))
+ if (tcp_checksum_complete(skb))
goto csum_error;
if ((int)skb->truesize > sk->sk_forward_alloc)
@@ -5430,7 +5404,7 @@
}
slow_path:
- if (len < (th->doff << 2) || tcp_checksum_complete_user(sk, skb))
+ if (len < (th->doff << 2) || tcp_checksum_complete(skb))
goto csum_error;
if (!th->ack && !th->rst && !th->syn)