Bluetooth: Remove L2CAP busy queue

The ERTM receive buffer is now handled in a way that does not require
the busy queue and the associated polling code.

Signed-off-by: Mat Martineau <mathewm@codeaurora.org>
Signed-off-by: Gustavo F. Padovan <padovan@profusion.mobi>

diff --git a/include/net/bluetooth/l2cap.h b/include/net/bluetooth/l2cap.h
index 66b8d96..578545a 100644 (file)
--- a/include/net/bluetooth/l2cap.h
+++ b/include/net/bluetooth/l2cap.h
@@ -37,7 +37,6 @@
 #define L2CAP_DEFAULT_MONITOR_TO       12000   /* 12 seconds */
 #define L2CAP_DEFAULT_MAX_PDU_SIZE     1009    /* Sized for 3-DH5 packet */
 #define L2CAP_DEFAULT_ACK_TO           200
-#define L2CAP_LOCAL_BUSY_TRIES         12
 #define L2CAP_LE_DEFAULT_MTU           23
 
 #define L2CAP_CONN_TIMEOUT     (40000) /* 40 seconds */
@@ -352,8 +351,6 @@ struct l2cap_chan {
        struct sk_buff          *tx_send_head;
        struct sk_buff_head     tx_q;
        struct sk_buff_head     srej_q;
-       struct sk_buff_head     busy_q;
-       struct work_struct      busy_work;
        struct list_head        srej_l;
 
        struct list_head list;
@@ -450,7 +447,6 @@ enum {
        CONN_REJ_ACT,
        CONN_SEND_FBIT,
        CONN_RNR_SENT,
-       CONN_SAR_RETRY,
 };
 
 #define __set_chan_timer(c, t) l2cap_set_timer(c, &c->chan_timer, (t))

diff --git a/net/bluetooth/l2cap_core.c b/net/bluetooth/l2cap_core.c
index 7ada21e..7343749 100644 (file)
--- a/net/bluetooth/l2cap_core.c
+++ b/net/bluetooth/l2cap_core.c
@@ -61,13 +61,9 @@ int disable_ertm;
 static u32 l2cap_feat_mask = L2CAP_FEAT_FIXED_CHAN;
 static u8 l2cap_fixed_chan[8] = { 0x02, };
 
-static struct workqueue_struct *_busy_wq;
-
 static LIST_HEAD(chan_list);
 static DEFINE_RWLOCK(chan_list_lock);
 
-static void l2cap_busy_work(struct work_struct *work);
-
 static struct sk_buff *l2cap_build_cmd(struct l2cap_conn *conn,
                                u8 code, u8 ident, u16 dlen, void *data);
 static void l2cap_send_cmd(struct l2cap_conn *conn, u8 ident, u8 code, u16 len,
@@ -395,7 +391,6 @@ static void l2cap_chan_del(struct l2cap_chan *chan, int err)
                __clear_ack_timer(chan);
 
                skb_queue_purge(&chan->srej_q);
-               skb_queue_purge(&chan->busy_q);
 
                list_for_each_entry_safe(l, tmp, &chan->srej_l, list) {
                        list_del(&l->list);
@@ -1874,11 +1869,9 @@ static inline void l2cap_ertm_init(struct l2cap_chan *chan)
        setup_timer(&chan->ack_timer, l2cap_ack_timeout, (unsigned long) chan);
 
        skb_queue_head_init(&chan->srej_q);
-       skb_queue_head_init(&chan->busy_q);
 
        INIT_LIST_HEAD(&chan->srej_l);
 
-       INIT_WORK(&chan->busy_work, l2cap_busy_work);
 
        sk->sk_backlog_rcv = l2cap_ertm_data_rcv;
 }
@@ -3183,32 +3176,27 @@ static int l2cap_ertm_reassembly_sdu(struct l2cap_chan *chan, struct sk_buff *sk
                if (!chan->sdu)
                        goto disconnect;
 
-               if (!test_bit(CONN_SAR_RETRY, &chan->conn_state)) {
-                       chan->partial_sdu_len += skb->len;
+               chan->partial_sdu_len += skb->len;
 
-                       if (chan->partial_sdu_len > chan->imtu)
-                               goto drop;
+               if (chan->partial_sdu_len > chan->imtu)
+                       goto drop;
 
-                       if (chan->partial_sdu_len != chan->sdu_len)
-                               goto drop;
+               if (chan->partial_sdu_len != chan->sdu_len)
+                       goto drop;
 
-                       memcpy(skb_put(chan->sdu, skb->len), skb->data, skb->len);
-               }
+               memcpy(skb_put(chan->sdu, skb->len), skb->data, skb->len);
 
                _skb = skb_clone(chan->sdu, GFP_ATOMIC);
                if (!_skb) {
-                       set_bit(CONN_SAR_RETRY, &chan->conn_state);
                        return -ENOMEM;
                }
 
                err = chan->ops->recv(chan->data, _skb);
                if (err < 0) {
                        kfree_skb(_skb);
-                       set_bit(CONN_SAR_RETRY, &chan->conn_state);
                        return err;
                }
 
-               clear_bit(CONN_SAR_RETRY, &chan->conn_state);
                clear_bit(CONN_SAR_SDU, &chan->conn_state);
 
                kfree_skb(chan->sdu);
@@ -3269,93 +3257,6 @@ done:
        BT_DBG("chan %p, Exit local busy", chan);
 }
 
-static int l2cap_try_push_rx_skb(struct l2cap_chan *chan)
-{
-       struct sk_buff *skb;
-       u16 control;
-       int err;
-
-       while ((skb = skb_dequeue(&chan->busy_q))) {
-               control = bt_cb(skb)->sar << L2CAP_CTRL_SAR_SHIFT;
-               err = l2cap_ertm_reassembly_sdu(chan, skb, control);
-               if (err < 0) {
-                       skb_queue_head(&chan->busy_q, skb);
-                       return -EBUSY;
-               }
-
-               chan->buffer_seq = (chan->buffer_seq + 1) % 64;
-       }
-
-       l2cap_ertm_exit_local_busy(chan);
-
-       return 0;
-}
-
-static void l2cap_busy_work(struct work_struct *work)
-{
-       DECLARE_WAITQUEUE(wait, current);
-       struct l2cap_chan *chan =
-               container_of(work, struct l2cap_chan, busy_work);
-       struct sock *sk = chan->sk;
-       int n_tries = 0, timeo = HZ/5, err;
-       struct sk_buff *skb;
-
-       lock_sock(sk);
-
-       add_wait_queue(sk_sleep(sk), &wait);
-       while ((skb = skb_peek(&chan->busy_q))) {
-               set_current_state(TASK_INTERRUPTIBLE);
-
-               if (n_tries++ > L2CAP_LOCAL_BUSY_TRIES) {
-                       err = -EBUSY;
-                       l2cap_send_disconn_req(chan->conn, chan, EBUSY);
-                       break;
-               }
-
-               if (!timeo)
-                       timeo = HZ/5;
-
-               if (signal_pending(current)) {
-                       err = sock_intr_errno(timeo);
-                       break;
-               }
-
-               release_sock(sk);
-               timeo = schedule_timeout(timeo);
-               lock_sock(sk);
-
-               err = sock_error(sk);
-               if (err)
-                       break;
-
-               if (l2cap_try_push_rx_skb(chan) == 0)
-                       break;
-       }
-
-       set_current_state(TASK_RUNNING);
-       remove_wait_queue(sk_sleep(sk), &wait);
-
-       release_sock(sk);
-}
-
-static int l2cap_push_rx_skb(struct l2cap_chan *chan, struct sk_buff *skb, u16 control)
-{
-       int err;
-
-       if (test_bit(CONN_LOCAL_BUSY, &chan->conn_state)) {
-               bt_cb(skb)->sar = control >> L2CAP_CTRL_SAR_SHIFT;
-               __skb_queue_tail(&chan->busy_q, skb);
-               return l2cap_try_push_rx_skb(chan);
-
-
-       }
-
-       err = l2cap_ertm_reassembly_sdu(chan, skb, control);
-       chan->buffer_seq = (chan->buffer_seq + 1) % 64;
-
-       return err;
-}
-
 void l2cap_chan_busy(struct l2cap_chan *chan, int busy)
 {
        if (chan->mode == L2CAP_MODE_ERTM) {
@@ -3613,7 +3514,6 @@ static inline int l2cap_data_channel_iframe(struct l2cap_chan *chan, u16 rx_cont
                chan->buffer_seq_srej = chan->buffer_seq;
 
                __skb_queue_head_init(&chan->srej_q);
-               __skb_queue_head_init(&chan->busy_q);
                l2cap_add_to_srej_queue(chan, skb, tx_seq, sar);
 
                set_bit(CONN_SEND_PBIT, &chan->conn_state);
@@ -3634,7 +3534,8 @@ expected:
                return 0;
        }
 
-       err = l2cap_push_rx_skb(chan, skb, rx_control);
+       err = l2cap_ertm_reassembly_sdu(chan, skb, rx_control);
+       chan->buffer_seq = (chan->buffer_seq + 1) % 64;
        if (err < 0) {
                l2cap_send_disconn_req(chan->conn, chan, ECONNRESET);
                return err;
@@ -4441,12 +4342,6 @@ int __init l2cap_init(void)
        if (err < 0)
                return err;
 
-       _busy_wq = create_singlethread_workqueue("l2cap");
-       if (!_busy_wq) {
-               err = -ENOMEM;
-               goto error;
-       }
-
        err = hci_register_proto(&l2cap_hci_proto);
        if (err < 0) {
                BT_ERR("L2CAP protocol registration failed");
@@ -4464,7 +4359,6 @@ int __init l2cap_init(void)
        return 0;
 
 error:
-       destroy_workqueue(_busy_wq);
        l2cap_cleanup_sockets();
        return err;
 }
@@ -4473,9 +4367,6 @@ void l2cap_exit(void)
 {
        debugfs_remove(l2cap_debugfs);
 
-       flush_workqueue(_busy_wq);
-       destroy_workqueue(_busy_wq);
-
        if (hci_unregister_proto(&l2cap_hci_proto) < 0)
                BT_ERR("L2CAP protocol unregistration failed");