Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756466AbYAXMn5 (ORCPT ); Thu, 24 Jan 2008 07:43:57 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1754841AbYAXMmM (ORCPT ); Thu, 24 Jan 2008 07:42:12 -0500 Received: from nat-132.atmel.no ([80.232.32.132]:57043 "EHLO relay.atmel.no" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1753282AbYAXMmC (ORCPT ); Thu, 24 Jan 2008 07:42:02 -0500 From: Haavard Skinnemoen To: Andrew Morton Cc: Andrew Victor , Remy Bohmer , Chip Coldwell , Marc Pignat , David Brownell , linux-kernel@vger.kernel.org, Alan Cox , Haavard Skinnemoen Subject: [PATCH -mm v4 3/9] atmel_serial: Use cpu_relax() when busy-waiting Date: Thu, 24 Jan 2008 13:41:45 +0100 Message-Id: <1201178511-12133-4-git-send-email-hskinnemoen@atmel.com> X-Mailer: git-send-email 1.5.3.8 In-Reply-To: <1201178511-12133-3-git-send-email-hskinnemoen@atmel.com> References: <1201178511-12133-1-git-send-email-hskinnemoen@atmel.com> <1201178511-12133-2-git-send-email-hskinnemoen@atmel.com> <1201178511-12133-3-git-send-email-hskinnemoen@atmel.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1444 Lines: 41 Replace two instances of barrier() with cpu_relax() since that's the right thing to do when busy-waiting. This does not actually change anything since cpu_relax() is defined as barrier() on both ARM and AVR32. Signed-off-by: Haavard Skinnemoen Acked-by: Andrew Victor --- drivers/serial/atmel_serial.c | 4 ++-- 1 files changed, 2 insertions(+), 2 deletions(-) diff --git a/drivers/serial/atmel_serial.c b/drivers/serial/atmel_serial.c index ee5d844..4b5c6ff 100644 --- a/drivers/serial/atmel_serial.c +++ b/drivers/serial/atmel_serial.c @@ -616,7 +616,7 @@ static void atmel_set_termios(struct uart_port *port, struct ktermios *termios, imr = UART_GET_IMR(port); UART_PUT_IDR(port, -1); while (!(UART_GET_CSR(port) & ATMEL_US_TXEMPTY)) - barrier(); + cpu_relax(); /* disable receiver and transmitter */ UART_PUT_CR(port, ATMEL_US_TXDIS | ATMEL_US_RXDIS); @@ -795,7 +795,7 @@ void __init atmel_register_uart_fns(struct atmel_port_fns *fns) static void atmel_console_putchar(struct uart_port *port, int ch) { while (!(UART_GET_CSR(port) & ATMEL_US_TXRDY)) - barrier(); + cpu_relax(); UART_PUT_CHAR(port, ch); } -- 1.5.3.8 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/