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Bluetooth: Make __l2cap_wait_ack more efficient

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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 <Dean_Jenkins@mentor.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
This commit is contained in:
Dean Jenkins 2015-06-23 17:59:33 +01:00 committed by Marcel Holtmann
parent 2baea85dec
commit f65468f6e2
1 changed files with 10 additions and 6 deletions
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16
net/bluetooth/l2cap_sock.c
View file

@ -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;