From: Alan Cox Date: Tue, 1 Jun 2010 20:52:59 +0000 (+0200) Subject: serial: trim locking on the helpers X-Git-Tag: firefly_0821_release~9833^2~1029^2~36 X-Git-Url: http://demsky.eecs.uci.edu/git/?a=commitdiff_plain;h=24fcc7c8cd0fcabcf37d455abe3501b3196fcf64;p=firefly-linux-kernel-4.4.55.git serial: trim locking on the helpers The port mutex protects port->tty, but these paths never need to walk from port->tty. They do need the low level lock as the API expects that but they already also take it. Thus we can drop the extra mutex lock calls here. Signed-off-by: Alan Cox Cc: Arnd Bergmann Signed-off-by: Greg Kroah-Hartman --- diff --git a/drivers/serial/serial_core.c b/drivers/serial/serial_core.c index 2379045e0871..0603e0d46d33 100644 --- a/drivers/serial/serial_core.c +++ b/drivers/serial/serial_core.c @@ -1506,12 +1506,10 @@ static int uart_carrier_raised(struct tty_port *port) struct uart_state *state = container_of(port, struct uart_state, port); struct uart_port *uport = state->uart_port; int mctrl; - mutex_lock(&port->mutex); spin_lock_irq(&uport->lock); uport->ops->enable_ms(uport); mctrl = uport->ops->get_mctrl(uport); spin_unlock_irq(&uport->lock); - mutex_unlock(&port->mutex); if (mctrl & TIOCM_CAR) return 1; return 0; @@ -1521,12 +1519,11 @@ static void uart_dtr_rts(struct tty_port *port, int onoff) { struct uart_state *state = container_of(port, struct uart_state, port); struct uart_port *uport = state->uart_port; - mutex_lock(&port->mutex); + if (onoff) uart_set_mctrl(uport, TIOCM_DTR | TIOCM_RTS); else uart_clear_mctrl(uport, TIOCM_DTR | TIOCM_RTS); - mutex_unlock(&port->mutex); } /*