From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: From: Marcel Holtmann To: linux-bluetooth@vger.kernel.org Subject: [PATCH 1/3] Bluetooth: Simplify packet copy in hci_send_to_monitor function Date: Sun, 11 Jan 2015 19:33:31 -0800 Message-Id: <1421033613-31738-1-git-send-email-marcel@holtmann.org> Sender: linux-bluetooth-owner@vger.kernel.org List-ID: Within the monitor functionality, the global atomic variable called monitor_promisc ensures that no memory allocation happend when there is actually no client listening. This means it is safe to just create a copy of the skb since it is guaranteed that at least one client exists. No extra checks needed. Signed-off-by: Marcel Holtmann --- net/bluetooth/hci_sock.c | 28 ++++++++++++---------------- 1 file changed, 12 insertions(+), 16 deletions(-) diff --git a/net/bluetooth/hci_sock.c b/net/bluetooth/hci_sock.c index e176a988625e..026e84a80659 100644 --- a/net/bluetooth/hci_sock.c +++ b/net/bluetooth/hci_sock.c @@ -221,6 +221,7 @@ void hci_send_to_monitor(struct hci_dev *hdev, struct sk_buff *skb) { struct sock *sk; struct sk_buff *skb_copy = NULL; + struct hci_mon_hdr *hdr; __le16 opcode; if (!atomic_read(&monitor_promisc)) @@ -251,6 +252,17 @@ void hci_send_to_monitor(struct hci_dev *hdev, struct sk_buff *skb) return; } + /* Create a private copy with headroom */ + skb_copy = __pskb_copy_fclone(skb, HCI_MON_HDR_SIZE, GFP_ATOMIC, true); + if (!skb_copy) + return; + + /* Put header before the data */ + hdr = (void *) skb_push(skb_copy, HCI_MON_HDR_SIZE); + hdr->opcode = opcode; + hdr->index = cpu_to_le16(hdev->id); + hdr->len = cpu_to_le16(skb->len); + read_lock(&hci_sk_list.lock); sk_for_each(sk, &hci_sk_list.head) { @@ -262,22 +274,6 @@ void hci_send_to_monitor(struct hci_dev *hdev, struct sk_buff *skb) if (hci_pi(sk)->channel != HCI_CHANNEL_MONITOR) continue; - if (!skb_copy) { - struct hci_mon_hdr *hdr; - - /* Create a private copy with headroom */ - skb_copy = __pskb_copy_fclone(skb, HCI_MON_HDR_SIZE, - GFP_ATOMIC, true); - if (!skb_copy) - continue; - - /* Put header before the data */ - hdr = (void *) skb_push(skb_copy, HCI_MON_HDR_SIZE); - hdr->opcode = opcode; - hdr->index = cpu_to_le16(hdev->id); - hdr->len = cpu_to_le16(skb->len); - } - nskb = skb_clone(skb_copy, GFP_ATOMIC); if (!nskb) continue; -- 2.1.0