[PATCH -next 09/10] serial: core: Remove extra locking in uart_write()

From: Peter Hurley
Date: Thu Oct 16 2014 - 16:56:06 EST


uart_start() only claims the port->lock to call __uart_start(),
which does the actual processing. Eliminate the extra acquire/release
in uart_write(); call __uart_start() directly with port->lock already
held.

Signed-off-by: Peter Hurley <peter@xxxxxxxxxxxxxxxxxx>
---
drivers/tty/serial/serial_core.c | 3 ++-
1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/drivers/tty/serial/serial_core.c b/drivers/tty/serial/serial_core.c
index e04ae58..6a3571e 100644
--- a/drivers/tty/serial/serial_core.c
+++ b/drivers/tty/serial/serial_core.c
@@ -537,9 +537,10 @@ static int uart_write(struct tty_struct *tty,
count -= c;
ret += c;
}
+
+ __uart_start(tty);
spin_unlock_irqrestore(&port->lock, flags);

- uart_start(tty);
return ret;
}

--
2.1.1

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