From: Thomas Gleixner <tglx@linutronix.de>
To: LKML <linux-kernel@vger.kernel.org>
Cc: Wolfgang Grandegger <wg@grandegger.com>,
Marc Kleine-Budde <mkl@pengutronix.de>,
Markus Pargmann <mpa@pengutronix.de>,
Benedikt Spranger <b.spranger@linutronix.de>,
linux-can@vger.kernel.org, netdev@vger.kernel.org
Subject: [patch 08/12] can: c_can: Makethe code readable
Date: Tue, 18 Mar 2014 17:19:12 -0000 [thread overview]
Message-ID: <20140318171127.430027680@linutronix.de> (raw)
In-Reply-To: 20140318171007.528610837@linutronix.de
[-- Attachment #1: can-c-can-make-code-readable.patch --]
[-- Type: text/plain, Size: 4302 bytes --]
If every other line contains line breaks, that's a clear sign for
indentation level madness. Split out the inner loop and move the code
to a separate function. gcc creates slightly worse code for that, but
we'll fix that in the next step.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
---
drivers/net/can/c_can/c_can.c | 107 +++++++++++++++++++++---------------------
1 file changed, 56 insertions(+), 51 deletions(-)
Index: linux/drivers/net/can/c_can/c_can.c
===================================================================
--- linux.orig/drivers/net/can/c_can/c_can.c
+++ linux/drivers/net/can/c_can/c_can.c
@@ -840,6 +840,52 @@ static u32 c_can_adjust_pending(u32 pend
return pend & ~((1 << lasts) - 1);
}
+static int c_can_read_objects(struct net_device *dev, struct c_can_priv *priv,
+ u32 pend, int quota)
+{
+ u32 pkts = 0, ctrl, obj;
+
+ while ((obj = ffs(pend)) && quota > 0) {
+ pend &= ~BIT(obj - 1);
+
+ c_can_object_get(dev, IF_RX, obj, IF_COMM_ALL & ~IF_COMM_TXRQST);
+ ctrl = priv->read_reg(priv, C_CAN_IFACE(MSGCTRL_REG, IF_RX));
+
+ if (ctrl & IF_MCONT_MSGLST) {
+ int n = c_can_handle_lost_msg_obj(dev, IF_RX, obj, ctrl);
+
+ pkts += n;
+ quota -= n;
+ continue;
+ }
+
+ /*
+ * This really should not happen, but this covers some
+ * odd HW behaviour. Do not remove that unless you
+ * want to brick your machine.
+ */
+ if (!(ctrl & IF_MCONT_NEWDAT))
+ continue;
+
+ /* read the data from the message object */
+ c_can_read_msg_object(dev, IF_RX, ctrl);
+
+ if (obj < C_CAN_MSG_RX_LOW_LAST)
+ c_can_mark_rx_msg_obj(dev, IF_RX, ctrl, obj);
+ else if (obj > C_CAN_MSG_RX_LOW_LAST)
+ /* activate this msg obj */
+ c_can_activate_rx_msg_obj(dev, IF_RX, ctrl, obj);
+ else if (obj == C_CAN_MSG_RX_LOW_LAST)
+ /* activate all lower message objects */
+ c_can_activate_all_lower_rx_msg_obj(dev, IF_RX, ctrl);
+
+ pkts++;
+ quota--;
+ } while ((obj = ffs(pend)) && quota > 0);
+
+ return pkts;
+}
+
/*
* theory of operation:
*
@@ -864,10 +910,8 @@ static u32 c_can_adjust_pending(u32 pend
*/
static int c_can_do_rx_poll(struct net_device *dev, int quota)
{
- u32 num_rx_pkts = 0;
- unsigned int msg_obj, msg_ctrl_save;
struct c_can_priv *priv = netdev_priv(dev);
- u32 val, pend = 0;
+ u32 pkts = 0, pend = 0, toread, n;
/*
* It is faster to read only one 16bit register. This is only possible
@@ -877,65 +921,26 @@ static int c_can_do_rx_poll(struct net_d
"Implementation does not support more message objects than 16");
while (quota > 0) {
-
if (!pend) {
pend = priv->read_reg(priv, C_CAN_INTPND1_REG);
if (!pend)
- return num_rx_pkts;
+ break;
/*
* If the pending field has a gap, handle the
* bits above the gap first.
*/
- val = c_can_adjust_pending(pend);
+ toread = c_can_adjust_pending(pend);
} else {
- val = pend;
+ toread = pend;
}
/* Remove the bits from pend */
- pend &= ~val;
-
- while ((msg_obj = ffs(val)) && quota > 0) {
- val &= ~BIT(msg_obj - 1);
-
- c_can_object_get(dev, IF_RX, msg_obj, IF_COMM_ALL &
- ~IF_COMM_TXRQST);
- msg_ctrl_save = priv->read_reg(priv,
- C_CAN_IFACE(MSGCTRL_REG, IF_RX));
-
- if (msg_ctrl_save & IF_MCONT_MSGLST) {
- int n;
-
- n = c_can_handle_lost_msg_obj(dev, IF_RX,
- msg_obj,
- msg_ctrl_save);
- num_rx_pkts += n;
- quota -=n;
- continue;
- }
-
- if (!(msg_ctrl_save & IF_MCONT_NEWDAT))
- continue;
-
- /* read the data from the message object */
- c_can_read_msg_object(dev, IF_RX, msg_ctrl_save);
-
- if (msg_obj < C_CAN_MSG_RX_LOW_LAST)
- c_can_mark_rx_msg_obj(dev, IF_RX,
- msg_ctrl_save, msg_obj);
- else if (msg_obj > C_CAN_MSG_RX_LOW_LAST)
- /* activate this msg obj */
- c_can_activate_rx_msg_obj(dev, IF_RX,
- msg_ctrl_save, msg_obj);
- else if (msg_obj == C_CAN_MSG_RX_LOW_LAST)
- /* activate all lower message objects */
- c_can_activate_all_lower_rx_msg_obj(dev,
- IF_RX, msg_ctrl_save);
-
- num_rx_pkts++;
- quota--;
- }
+ pend &= ~toread;
+ /* Read the objects */
+ n = c_can_read_objects(dev, priv, toread, quota);
+ pkts += n;
+ quota -= n;
}
-
- return num_rx_pkts;
+ return pkts;
}
static inline int c_can_has_and_handle_berr(struct c_can_priv *priv)
next prev parent reply other threads:[~2014-03-18 17:19 UTC|newest]
Thread overview: 33+ messages / expand[flat|nested] mbox.gz Atom feed top
2014-03-18 17:19 [patch 00/12] can: c_can: Fix a series of serious bugs and improve the performance Thomas Gleixner
2014-03-18 17:19 ` [patch 01/12] can: c_can: Wait for CONTROL_INIT to be cleared Thomas Gleixner
2014-03-18 18:11 ` Marc Kleine-Budde
2014-03-18 18:19 ` Thomas Gleixner
2014-03-18 17:19 ` [patch 02/12] can: c_can: Fix hardware raminit function Thomas Gleixner
2014-03-18 18:38 ` Marc Kleine-Budde
2014-03-18 22:15 ` Thomas Gleixner
2014-03-19 6:37 ` Oliver Hartkopp
2014-03-19 9:22 ` Thomas Gleixner
2014-03-18 17:19 ` [patch 03/12] can: c_can: Make it SMP safe Thomas Gleixner
2014-03-18 18:46 ` Marc Kleine-Budde
2014-03-18 19:40 ` Thomas Gleixner
2014-03-18 17:19 ` [patch 04/12] can: c_can: Fix buffer ordering for real Thomas Gleixner
2014-03-18 17:19 ` [patch 05/12] can: c_can: Fix the lost message handling Thomas Gleixner
2014-03-18 17:19 ` [patch 06/12] can: c_can: Remove braindamaged EOB exit Thomas Gleixner
2014-03-18 17:19 ` [patch 07/12] can: c_can: Provide protection in the xmit path Thomas Gleixner
2014-03-18 17:19 ` Thomas Gleixner [this message]
2014-03-18 17:37 ` [patch 08/12] can: c_can: Makethe code readable Joe Perches
2014-03-18 18:23 ` Thomas Gleixner
2014-03-18 18:27 ` [patch 08/12 V2] " Thomas Gleixner
2014-03-18 17:19 ` [patch 09/12] can: c_can: Reduce register access for real Thomas Gleixner
2014-03-18 17:19 ` [patch 11/12] can: c_can: Simplify TX interrupt cleanup Thomas Gleixner
2014-03-18 17:19 ` [patch 10/12] can: c_can: Store dlc private Thomas Gleixner
2014-03-18 17:19 ` [patch 12/12] can: c_can: Avoid led toggling for every packet Thomas Gleixner
2014-03-18 20:18 ` can: c_can: Reduce interrupt load by 50% Thomas Gleixner
2014-03-18 20:35 ` Joe Perches
2014-03-18 20:43 ` Thomas Gleixner
2014-03-18 21:27 ` Joe Perches
2014-03-31 22:35 ` [patch 00/12] can: c_can: Fix a series of serious bugs and improve the performance Thomas Gleixner
2014-04-01 8:09 ` Marc Kleine-Budde
2014-04-01 9:07 ` Thomas Gleixner
2014-04-01 9:09 ` Marc Kleine-Budde
2014-04-01 21:29 ` Marc Kleine-Budde
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