[PATCH] Serial: Ensure error paths are marked with unlikely()

Ensure ARM serial driver error paths are marked with the
unlikely() compiler hint.
Signed-off-by: Russell King <rmk@arm.linux.org.uk>

drivers/serial/21285.c

@@ -110,7 +110,7 @@ static irqreturn_t serial21285_rx_chars(int irq, void *dev_id, struct pt_regs *r
 		port->icount.rx++;
 
 		rxs = *CSR_RXSTAT | RXSTAT_DUMMY_READ;
-		if (rxs & RXSTAT_ANYERR) {
+		if (unlikely(rxs & RXSTAT_ANYERR)) {
 			if (rxs & RXSTAT_PARITY)
 				port->icount.parity++;
 			else if (rxs & RXSTAT_FRAME)

drivers/serial/amba-pl010.c

@@ -172,7 +172,7 @@ pl010_rx_chars(struct uart_port *port)
 		 * out of the main execution path
 		 */
 		rsr = UART_GET_RSR(port) | UART_DUMMY_RSR_RX;
-		if (rsr & UART01x_RSR_ANY) {
+		if (unlikely(rsr & UART01x_RSR_ANY)) {
 			if (rsr & UART01x_RSR_BE) {
 				rsr &= ~(UART01x_RSR_FE | UART01x_RSR_PE);
 				port->icount.brk++;

drivers/serial/amba-pl011.c

@@ -137,7 +137,7 @@ pl011_rx_chars(struct uart_amba_port *uap)
 		 * out of the main execution path
 		 */
 		rsr = readw(uap->port.membase + UART01x_RSR) | UART_DUMMY_RSR_RX;
-		if (rsr & UART01x_RSR_ANY) {
+		if (unlikely(rsr & UART01x_RSR_ANY)) {
 			if (rsr & UART01x_RSR_BE) {
 				rsr &= ~(UART01x_RSR_FE | UART01x_RSR_PE);
 				uap->port.icount.brk++;

drivers/serial/clps711x.c

@@ -116,7 +116,7 @@ static irqreturn_t clps711xuart_int_rx(int irq, void *dev_id, struct pt_regs *re
 		 * Note that the error handling code is
 		 * out of the main execution path
 		 */
-		if (ch & UART_ANY_ERR)
+		if (unlikely(ch & UART_ANY_ERR))
 			goto handle_error;
 
 		if (uart_handle_sysrq_char(port, ch, regs))

drivers/serial/s3c2410.c

@@ -364,7 +364,7 @@ s3c24xx_serial_rx_chars(int irq, void *dev_id, struct pt_regs *regs)
 		flag = TTY_NORMAL;
 		port->icount.rx++;
 
-		if (uerstat & S3C2410_UERSTAT_ANY) {
+		if (unlikely(uerstat & S3C2410_UERSTAT_ANY)) {
 			dbg("rxerr: port ch=0x%02x, rxs=0x%08x\n",
 			    ch, uerstat);
 

drivers/serial/serial_lh7a40x.c

@@ -162,7 +162,7 @@ lh7a40xuart_rx_chars (struct uart_port* port)
 		flag = TTY_NORMAL;
 		++port->icount.rx;
 
-		if (data & RxError) {	/* Quick check, short-circuit */
+		if (unlikely(data & RxError)) {	/* Quick check, short-circuit */
 			if (data & RxBreak) {
 				data &= ~(RxFramingError | RxParityError);
 				++port->icount.brk;