From f65468f6e26c3bd05e642e10e80a485b99b7de05 Mon Sep 17 00:00:00 2001 From: Dean Jenkins Date: Tue, 23 Jun 2015 17:59:33 +0100 Subject: [PATCH] Bluetooth: Make __l2cap_wait_ack more efficient Use chan->state instead of chan->conn because waiting for ACK's is only possible in the BT_CONNECTED state. Also avoids reference to the conn structure so makes locking easier. Only call __l2cap_wait_ack() when the needed condition of chan->unacked_frames > 0 && chan->state == BT_CONNECTED is true and convert the while loop to a do while loop. __l2cap_wait_ack() change the function prototype to pass in the chan variable as chan is already available in the calling function l2cap_sock_shutdown(). Avoids locking issues. Signed-off-by: Dean Jenkins Signed-off-by: Marcel Holtmann --- net/bluetooth/l2cap_sock.c | 16 ++++++++++------ 1 file changed, 10 insertions(+), 6 deletions(-) diff --git a/net/bluetooth/l2cap_sock.c b/net/bluetooth/l2cap_sock.c index 3794c2386c21..29042880c449 100644 --- a/net/bluetooth/l2cap_sock.c +++ b/net/bluetooth/l2cap_sock.c @@ -1054,16 +1054,15 @@ static void l2cap_sock_kill(struct sock *sk) sock_put(sk); } -static int __l2cap_wait_ack(struct sock *sk) +static int __l2cap_wait_ack(struct sock *sk, struct l2cap_chan *chan) { - struct l2cap_chan *chan = l2cap_pi(sk)->chan; DECLARE_WAITQUEUE(wait, current); int err = 0; int timeo = HZ/5; add_wait_queue(sk_sleep(sk), &wait); set_current_state(TASK_INTERRUPTIBLE); - while (chan->unacked_frames > 0 && chan->conn) { + do { if (!timeo) timeo = HZ/5; @@ -1080,7 +1079,10 @@ static int __l2cap_wait_ack(struct sock *sk) err = sock_error(sk); if (err) break; - } + + } while (chan->unacked_frames > 0 && + chan->state == BT_CONNECTED); + set_current_state(TASK_RUNNING); remove_wait_queue(sk_sleep(sk), &wait); return err; @@ -1115,8 +1117,10 @@ static int l2cap_sock_shutdown(struct socket *sock, int how) lock_sock(sk); if (!sk->sk_shutdown) { - if (chan->mode == L2CAP_MODE_ERTM) - err = __l2cap_wait_ack(sk); + if (chan->mode == L2CAP_MODE_ERTM && + chan->unacked_frames > 0 && + chan->state == BT_CONNECTED) + err = __l2cap_wait_ack(sk, chan); sk->sk_shutdown = SHUTDOWN_MASK; -- 2.11.0