[PATCH 3/4] : More use DIV_ROUND_UP

From: Julia Lawall
Date: Sat Feb 16 2008 - 09:52:20 EST


From: Julia Lawall <julia@xxxxxxx>

The kernel.h macro DIV_ROUND_UP performs the computation (((n) + (d) - 1) /
(d)) but is perhaps more readable.

An extract of the semantic patch that makes this change is as follows:
(http://www.emn.fr/x-info/coccinelle/)

// <smpl>
@haskernel@
@@

#include <linux/kernel.h>

@depends on haskernel@
expression n,d;
@@

(
- (n + d - 1) / d
+ DIV_ROUND_UP(n,d)
|
- (n + (d - 1)) / d
+ DIV_ROUND_UP(n,d)
)

@depends on haskernel@
expression n,d;
@@

- DIV_ROUND_UP((n),d)
+ DIV_ROUND_UP(n,d)

@depends on haskernel@
expression n,d;
@@

- DIV_ROUND_UP(n,(d))
+ DIV_ROUND_UP(n,d)
// </smpl>

Signed-off-by: Julia Lawall <julia@xxxxxxx>

---

diff -u -p a/drivers/usb/host/r8a66597-hcd.c b/drivers/usb/host/r8a66597-hcd.c
--- a/drivers/usb/host/r8a66597-hcd.c 2007-12-31 08:43:30.000000000 +0100
+++ b/drivers/usb/host/r8a66597-hcd.c 2008-02-15 22:31:12.000000000 +0100
@@ -959,9 +959,9 @@ static void prepare_packet_read(struct r
r8a66597_write(r8a66597, TRCLR,
td->pipe->pipetre);
r8a66597_write(r8a66597,
- (urb->transfer_buffer_length
- + td->maxpacket - 1)
- / td->maxpacket,
+ DIV_ROUND_UP
+ (urb->transfer_buffer_length,
+ td->maxpacket),
td->pipe->pipetrn);
r8a66597_bset(r8a66597, TRENB,
td->pipe->pipetre);
diff -u -p a/drivers/usb/misc/usbtest.c b/drivers/usb/misc/usbtest.c
--- a/drivers/usb/misc/usbtest.c 2008-02-02 15:28:32.000000000 +0100
+++ b/drivers/usb/misc/usbtest.c 2008-02-15 22:31:16.000000000 +0100
@@ -1403,7 +1403,7 @@ static struct urb *iso_alloc_urb (
return NULL;
maxp = 0x7ff & le16_to_cpu(desc->wMaxPacketSize);
maxp *= 1 + (0x3 & (le16_to_cpu(desc->wMaxPacketSize) >> 11));
- packets = (bytes + maxp - 1) / maxp;
+ packets = DIV_ROUND_UP(bytes, maxp);

urb = usb_alloc_urb (packets, GFP_KERNEL);
if (!urb)
diff -u -p a/drivers/usb/serial/ftdi_sio.c b/drivers/usb/serial/ftdi_sio.c
--- a/drivers/usb/serial/ftdi_sio.c 2008-02-02 15:28:32.000000000 +0100
+++ b/drivers/usb/serial/ftdi_sio.c 2008-02-15 22:31:19.000000000 +0100
@@ -1380,7 +1380,7 @@ static void ftdi_write_bulk_callback (st
data_offset = priv->write_offset;
if (data_offset > 0) {
/* Subtract the control bytes */
- countback -= (data_offset * ((countback + (PKTSZ - 1)) / PKTSZ));
+ countback -= (data_offset * DIV_ROUND_UP(countback, PKTSZ));
}
spin_lock_irqsave(&priv->tx_lock, flags);
--priv->tx_outstanding_urbs;
@@ -1480,7 +1480,7 @@ static void ftdi_read_bulk_callback (str

/* count data bytes, but not status bytes */
countread = urb->actual_length;
- countread -= 2 * ((countread + (PKTSZ - 1)) / PKTSZ);
+ countread -= 2 * DIV_ROUND_UP(countread, PKTSZ);
spin_lock_irqsave(&priv->rx_lock, flags);
priv->rx_bytes += countread;
spin_unlock_irqrestore(&priv->rx_lock, flags);
diff -u -p a/drivers/usb/serial/io_ti.c b/drivers/usb/serial/io_ti.c
--- a/drivers/usb/serial/io_ti.c 2008-02-02 15:28:32.000000000 +0100
+++ b/drivers/usb/serial/io_ti.c 2008-02-15 22:31:21.000000000 +0100
@@ -655,7 +655,7 @@ static void TIChasePort(struct edgeport_
/* (TIIsTxActive doesn't seem to wait for the last byte) */
if ((baud_rate=port->baud_rate) == 0)
baud_rate = 50;
- msleep(max(1,(10000+baud_rate-1)/baud_rate));
+ msleep(max(1, DIV_ROUND_UP(10000, baud_rate)));
}

static int TIChooseConfiguration (struct usb_device *dev)
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/