Bluetooth: Remove the send_lock spinlock from ERTM
Using a lock to deal with the ERTM race condition - interruption with
new data from the hci layer - is wrong. We should use the native skb
backlog queue.
Signed-off-by: Gustavo F. Padovan <padovan@profusion.mobi>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
diff --git a/include/net/bluetooth/l2cap.h b/include/net/bluetooth/l2cap.h
index f8bae54..7df70e4 100644
--- a/include/net/bluetooth/l2cap.h
+++ b/include/net/bluetooth/l2cap.h
@@ -358,7 +358,6 @@
__le16 sport;
- spinlock_t send_lock;
struct timer_list retrans_timer;
struct timer_list monitor_timer;
struct timer_list ack_timer;
diff --git a/net/bluetooth/l2cap.c b/net/bluetooth/l2cap.c
index f6e46fd..dc8601f 100644
--- a/net/bluetooth/l2cap.c
+++ b/net/bluetooth/l2cap.c
@@ -1562,16 +1562,11 @@
struct l2cap_pinfo *pi = l2cap_pi(sk);
int ret;
- spin_lock_bh(&pi->send_lock);
-
if (!skb_queue_empty(TX_QUEUE(sk)))
sk->sk_send_head = TX_QUEUE(sk)->next;
pi->next_tx_seq = pi->expected_ack_seq;
ret = l2cap_ertm_send(sk);
-
- spin_unlock_bh(&pi->send_lock);
-
return ret;
}
@@ -1579,7 +1574,6 @@
{
struct sock *sk = (struct sock *)pi;
u16 control = 0;
- int nframes;
control |= pi->buffer_seq << L2CAP_CTRL_REQSEQ_SHIFT;
@@ -1590,11 +1584,7 @@
return;
}
- spin_lock_bh(&pi->send_lock);
- nframes = l2cap_ertm_send(sk);
- spin_unlock_bh(&pi->send_lock);
-
- if (nframes > 0)
+ if (l2cap_ertm_send(sk) > 0)
return;
control |= L2CAP_SUPER_RCV_READY;
@@ -1789,10 +1779,8 @@
size += buflen;
}
skb_queue_splice_tail(&sar_queue, TX_QUEUE(sk));
- spin_lock_bh(&pi->send_lock);
if (sk->sk_send_head == NULL)
sk->sk_send_head = sar_queue.next;
- spin_unlock_bh(&pi->send_lock);
return size;
}
@@ -1864,14 +1852,9 @@
}
__skb_queue_tail(TX_QUEUE(sk), skb);
- if (pi->mode == L2CAP_MODE_ERTM)
- spin_lock_bh(&pi->send_lock);
-
if (sk->sk_send_head == NULL)
sk->sk_send_head = skb;
- if (pi->mode == L2CAP_MODE_ERTM)
- spin_unlock_bh(&pi->send_lock);
} else {
/* Segment SDU into multiples PDUs */
err = l2cap_sar_segment_sdu(sk, msg, len);
@@ -1887,9 +1870,7 @@
err = len;
break;
}
- spin_lock_bh(&pi->send_lock);
err = l2cap_ertm_send(sk);
- spin_unlock_bh(&pi->send_lock);
}
if (err >= 0)
@@ -2464,7 +2445,6 @@
__skb_queue_head_init(SREJ_QUEUE(sk));
__skb_queue_head_init(BUSY_QUEUE(sk));
- spin_lock_init(&l2cap_pi(sk)->send_lock);
INIT_WORK(&l2cap_pi(sk)->busy_work, l2cap_busy_work);
}
@@ -3462,9 +3442,7 @@
if (pi->conn_state & L2CAP_CONN_REMOTE_BUSY)
l2cap_retransmit_frames(sk);
- spin_lock_bh(&pi->send_lock);
l2cap_ertm_send(sk);
- spin_unlock_bh(&pi->send_lock);
if (!(pi->conn_state & L2CAP_CONN_LOCAL_BUSY) &&
pi->frames_sent == 0) {
@@ -4066,9 +4044,7 @@
if (pi->conn_state & L2CAP_CONN_SREJ_SENT) {
l2cap_send_ack(pi);
} else {
- spin_lock_bh(&pi->send_lock);
l2cap_ertm_send(sk);
- spin_unlock_bh(&pi->send_lock);
}
}
}
@@ -4113,9 +4089,7 @@
pi->conn_state |= L2CAP_CONN_SEND_FBIT;
l2cap_retransmit_one_frame(sk, tx_seq);
- spin_lock_bh(&pi->send_lock);
l2cap_ertm_send(sk);
- spin_unlock_bh(&pi->send_lock);
if (pi->conn_state & L2CAP_CONN_WAIT_F) {
pi->srej_save_reqseq = tx_seq;