Return-Path: Sender: "Gustavo F. Padovan" From: "Gustavo F. Padovan" To: linux-bluetooth@vger.kernel.org Cc: netdev@vger.kernel.org, linux-kernel@vger.kernel.org, marcel@holtmann.org Subject: [PATCH] Bluetooth: Simplify L2CAP Streaming mode sending Date: Mon, 30 Aug 2010 20:10:24 -0300 Message-Id: <1283209824-8795-2-git-send-email-padovan@profusion.mobi> In-Reply-To: <1283209824-8795-1-git-send-email-padovan@profusion.mobi> References: <1283209824-8795-1-git-send-email-padovan@profusion.mobi> List-ID: As we don't have any error control on the Streaming mode, i.e., we don't need to keep a copy of the skb for later resending we don't need to call skb_clone() on it. Then we can go one further here, and dequeue the skb before sending it, that also means we don't need to look to sk->sk_send_head anymore. This patch fixes a bug in Streaming mode sending procedure, the call to skb_clone() was making the system run into OOM condition. I never got that before 2.6.36, so I'm think that we acctually have regression there. Anyway, the patch saves memory and time when sending Streaming mode data, so it is good to mainline. Signed-off-by: Gustavo F. Padovan --- net/bluetooth/l2cap.c | 24 +++++++----------------- 1 files changed, 7 insertions(+), 17 deletions(-) diff --git a/net/bluetooth/l2cap.c b/net/bluetooth/l2cap.c index fadf26b..80e98cd 100644 --- a/net/bluetooth/l2cap.c +++ b/net/bluetooth/l2cap.c @@ -1441,33 +1441,23 @@ static inline void l2cap_do_send(struct sock *sk, struct sk_buff *skb) static void l2cap_streaming_send(struct sock *sk) { - struct sk_buff *skb, *tx_skb; + struct sk_buff *skb; struct l2cap_pinfo *pi = l2cap_pi(sk); u16 control, fcs; - while ((skb = sk->sk_send_head)) { - tx_skb = skb_clone(skb, GFP_ATOMIC); - - control = get_unaligned_le16(tx_skb->data + L2CAP_HDR_SIZE); + while ((skb = skb_dequeue(TX_QUEUE(sk)))) { + control = get_unaligned_le16(skb->data + L2CAP_HDR_SIZE); control |= pi->next_tx_seq << L2CAP_CTRL_TXSEQ_SHIFT; - put_unaligned_le16(control, tx_skb->data + L2CAP_HDR_SIZE); + put_unaligned_le16(control, skb->data + L2CAP_HDR_SIZE); if (pi->fcs == L2CAP_FCS_CRC16) { - fcs = crc16(0, (u8 *)tx_skb->data, tx_skb->len - 2); - put_unaligned_le16(fcs, tx_skb->data + tx_skb->len - 2); + fcs = crc16(0, (u8 *)skb->data, skb->len - 2); + put_unaligned_le16(fcs, skb->data + skb->len - 2); } - l2cap_do_send(sk, tx_skb); + l2cap_do_send(sk, skb); pi->next_tx_seq = (pi->next_tx_seq + 1) % 64; - - if (skb_queue_is_last(TX_QUEUE(sk), skb)) - sk->sk_send_head = NULL; - else - sk->sk_send_head = skb_queue_next(TX_QUEUE(sk), skb); - - skb = skb_dequeue(TX_QUEUE(sk)); - kfree_skb(skb); } } -- 1.7.2.2