From mboxrd@z Thu Jan 1 00:00:00 1970 From: Joe Perches Subject: Re: [PATCH v2] can: c_can: Speed up rx_poll function Date: Tue, 29 Oct 2013 01:31:01 -0700 Message-ID: <1383035461.2713.1.camel@joe-AO722> References: <1383035267-19604-1-git-send-email-mpa@pengutronix.de> Mime-Version: 1.0 Content-Type: text/plain; charset="ISO-8859-1" Content-Transfer-Encoding: 7bit Cc: Marc Kleine-Budde , Wolfgang Grandegger , linux-can@vger.kernel.org, netdev@vger.kernel.org, linux-kernel@vger.kernel.org, kernel@pengutronix.de To: Markus Pargmann Return-path: In-Reply-To: <1383035267-19604-1-git-send-email-mpa@pengutronix.de> Sender: linux-can-owner@vger.kernel.org List-Id: netdev.vger.kernel.org On Tue, 2013-10-29 at 09:27 +0100, Markus Pargmann wrote: > This patch speeds up the rx_poll function by reducing the number of > register reads. [] > The third change is to replace the for-loop by a find_next_bit loop. You need to update the commit message. > diff --git a/drivers/net/can/c_can/c_can.c b/drivers/net/can/c_can/c_can.c [] > @@ -798,17 +798,19 @@ static int c_can_do_rx_poll(struct net_device *dev, int quota) [] > + while (quota > 0 && (val = priv->read_reg(priv, C_CAN_INTPND1_REG))) { > + while ((msg_obj = ffs(val)) && quota > 0) { > + val &= ~BIT(msg_obj - 1);