Commit 8ebfe885 authored by Lance Roy's avatar Lance Roy Committed by Greg Kroah-Hartman
Browse files

TTY: sn_console: Replace spin_is_locked() with spin_trylock() 



sn_sal_console_write() used spin_is_locked() + spin_lock() to get
achieve the same thing as a spin_trylock(), so simplify it by using that
instead. This is also a step towards possibly removing spin_is_locked().

Signed-off-by: default avatarLance Roy <ldr709@gmail.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Jiri Slaby <jslaby@suse.com>
Cc: <linux-serial@vger.kernel.org>
Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
parent 817e9bc8

drivers/tty/serial/sn_console.c

+6 −9
Original line number Diff line number Diff line
@@ -888,7 +888,7 @@ sn_sal_console_write(struct console *co, const char *s, unsigned count) 


	/* somebody really wants this output, might be an

	 * oops, kdb, panic, etc.  make sure they get it. */

	if (spin_is_locked(&port->sc_port.lock)) {

	if (!spin_trylock_irqsave(&port->sc_port.lock, flags)) {

		int lhead = port->sc_port.state->xmit.head;

		int ltail = port->sc_port.state->xmit.tail;

		int counter, got_lock = 0;
@@ -905,13 +905,11 @@ sn_sal_console_write(struct console *co, const char *s, unsigned count) 
		 */



		for (counter = 0; counter < 150; mdelay(125), counter++) {

			if (!spin_is_locked(&port->sc_port.lock)

			    || stole_lock) {

				if (!stole_lock) {

					spin_lock_irqsave(&port->sc_port.lock,

							  flags);

			if (stole_lock)

				break;



			if (spin_trylock_irqsave(&port->sc_port.lock, flags)) {

				got_lock = 1;

				}

				break;

			} else {

				/* still locked */
@@ -938,7 +936,6 @@ sn_sal_console_write(struct console *co, const char *s, unsigned count) 
		puts_raw_fixed(port->sc_ops->sal_puts_raw, s, count);

	} else {

		stole_lock = 0;

		spin_lock_irqsave(&port->sc_port.lock, flags);

		sn_transmit_chars(port, 1);

		spin_unlock_irqrestore(&port->sc_port.lock, flags);

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