LKML Archive on lore.kernel.org
help / color / mirror / Atom feed
From: Julia Lawall <julia@diku.dk>
To: jeremy@xensource.com, xen-devel@lists.xensource.com,
	linux-kernel@vger.kernel.org, kernel-janitors@vger.kernel.org
Subject: [PATCH 1/6] arch/x86/xen: Use DIV_ROUND_UP
Date: Thu, 14 Feb 2008 16:14:04 +0100 (MET)	[thread overview]
Message-ID: <Pine.LNX.4.58.0802141613300.1185@pc-041.diku.dk> (raw)

From: Julia Lawall <julia@diku.dk>

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@diku.dk>

---

diff -u -p a/arch/x86/xen/enlighten.c b/arch/x86/xen/enlighten.c
--- a/arch/x86/xen/enlighten.c 2008-02-02 15:28:17.000000000 +0100
+++ b/arch/x86/xen/enlighten.c 2008-02-13 20:48:15.000000000 +0100
@@ -293,7 +293,7 @@ static void xen_load_gdt(const struct de
 	unsigned long *frames;
 	unsigned long va = dtr->address;
 	unsigned int size = dtr->size + 1;
-	unsigned pages = (size + PAGE_SIZE - 1) / PAGE_SIZE;
+	unsigned pages = DIV_ROUND_UP(size, PAGE_SIZE);
 	int f;
 	struct multicall_space mcs;


                 reply	other threads:[~2008-02-14 15:14 UTC|newest]

Thread overview: [no followups] expand[flat|nested]  mbox.gz  Atom feed

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=Pine.LNX.4.58.0802141613300.1185@pc-041.diku.dk \
    --to=julia@diku.dk \
    --cc=jeremy@xensource.com \
    --cc=kernel-janitors@vger.kernel.org \
    --cc=linux-kernel@vger.kernel.org \
    --cc=xen-devel@lists.xensource.com \
    --subject='Re: [PATCH 1/6] arch/x86/xen: Use DIV_ROUND_UP' \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link

This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).