mirror of
https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
synced 2024-08-21 16:29:59 +00:00
Bluetooth: Remove useless rx_lock spinlock
rx_lock spinlock is only used in hci_uart_tty_receive() which is the receive_buf ldisc callback. hci_uart_tty_receive() is protected from re-entrance by its only caller (flush_to_ldisc() in drivers/tty/tty_buffer.c) which held a mutex (buf->lock) for this section. This lock allows "safe use of the line discipline's receive_buf() method by excluding the buffer work and any pending flush from using the flip buffer." (comments from tty_buffer_lock_exclusive() in drivers/tty/tty_buffer.c) So, no need to double protect this resource with rx_lock. Signed-off-by: Frederic Danis <frederic.danis@linux.intel.com> Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
This commit is contained in:
parent
b7a622a249
commit
7649faff1c
2 changed files with 3 additions and 6 deletions
|
@ -470,8 +470,6 @@ static int hci_uart_tty_open(struct tty_struct *tty)
|
|||
INIT_WORK(&hu->init_ready, hci_uart_init_work);
|
||||
INIT_WORK(&hu->write_work, hci_uart_write_work);
|
||||
|
||||
spin_lock_init(&hu->rx_lock);
|
||||
|
||||
/* Flush any pending characters in the driver and line discipline. */
|
||||
|
||||
/* FIXME: why is this needed. Note don't use ldisc_ref here as the
|
||||
|
@ -569,14 +567,14 @@ static void hci_uart_tty_receive(struct tty_struct *tty, const u8 *data,
|
|||
if (!test_bit(HCI_UART_PROTO_SET, &hu->flags))
|
||||
return;
|
||||
|
||||
spin_lock(&hu->rx_lock);
|
||||
/* It does not need a lock here as it is already protected by a mutex in
|
||||
* tty caller
|
||||
*/
|
||||
hu->proto->recv(hu, data, count);
|
||||
|
||||
if (hu->hdev)
|
||||
hu->hdev->stat.byte_rx += count;
|
||||
|
||||
spin_unlock(&hu->rx_lock);
|
||||
|
||||
tty_unthrottle(tty);
|
||||
}
|
||||
|
||||
|
|
|
@ -85,7 +85,6 @@ struct hci_uart {
|
|||
|
||||
struct sk_buff *tx_skb;
|
||||
unsigned long tx_state;
|
||||
spinlock_t rx_lock;
|
||||
|
||||
unsigned int init_speed;
|
||||
unsigned int oper_speed;
|
||||
|
|
Loading…
Reference in a new issue