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* [RFC][PATCH 2/5] pagemap: use PAGE_MASK/PAGE_ALIGN()
  2007-08-07 22:33 [RFC][PATCH 1/5] pagemap: remove file header Dave Hansen
@ 2007-08-07 22:33 ` Dave Hansen
  2007-08-08  1:54   ` Matt Mackall
  0 siblings, 1 reply; 4+ messages in thread
From: Dave Hansen @ 2007-08-07 22:33 UTC (permalink / raw)
  To: mpm; +Cc: linux-kernel, serue, Dave Hansen


Use existing macros (PAGE_MASK/PAGE_ALIGN()) instead of
open-coding them.

Signed-off-by: Dave Hansen <haveblue@us.ibm.com>
---

 lxc-dave/fs/proc/task_mmu.c |    4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff -puN fs/proc/task_mmu.c~pagemap-use-PAGE_MASK fs/proc/task_mmu.c
--- lxc/fs/proc/task_mmu.c~pagemap-use-PAGE_MASK	2007-08-07 15:30:52.000000000 -0700
+++ lxc-dave/fs/proc/task_mmu.c	2007-08-07 15:30:52.000000000 -0700
@@ -669,9 +669,9 @@ static ssize_t pagemap_read(struct file 
 		goto out;
 
 	ret = -ENOMEM;
-	uaddr = (unsigned long)buf & ~(PAGE_SIZE-1);
+	uaddr = (unsigned long)buf & PAGE_MASK;
 	uend = (unsigned long)(buf + count);
-	pagecount = (uend - uaddr + PAGE_SIZE-1) / PAGE_SIZE;
+	pagecount = (uend - PAGE_ALIGN(uaddr)) / PAGE_SIZE;
 	pages = kmalloc(pagecount * sizeof(struct page *), GFP_KERNEL);
 	if (!pages)
 		goto out_task;
_

^ permalink raw reply	[flat|nested] 4+ messages in thread

* Re: [RFC][PATCH 2/5] pagemap: use PAGE_MASK/PAGE_ALIGN()
  2007-08-07 22:33 ` [RFC][PATCH 2/5] pagemap: use PAGE_MASK/PAGE_ALIGN() Dave Hansen
@ 2007-08-08  1:54   ` Matt Mackall
  0 siblings, 0 replies; 4+ messages in thread
From: Matt Mackall @ 2007-08-08  1:54 UTC (permalink / raw)
  To: Dave Hansen; +Cc: linux-kernel, serue

On Tue, Aug 07, 2007 at 03:33:01PM -0700, Dave Hansen wrote:
> 
> Use existing macros (PAGE_MASK/PAGE_ALIGN()) instead of
> open-coding them.

Absolutely.

Acked-by: Matt Mackall <mpm@selenic.com>

-- 
Mathematics is the supreme nostalgia of our time.

^ permalink raw reply	[flat|nested] 4+ messages in thread

* Re: [RFC][PATCH 2/5] pagemap: use PAGE_MASK/PAGE_ALIGN()
       [not found] ` <8PFSA-6mt-1@gated-at.bofh.it>
@ 2007-08-08  7:38   ` Christian Ehrhardt
  2007-08-08 15:11     ` Dave Hansen
  0 siblings, 1 reply; 4+ messages in thread
From: Christian Ehrhardt @ 2007-08-08  7:38 UTC (permalink / raw)
  To: Dave Hansen; +Cc: linux-kernel, serue, Dave Hansen

In linux.kernel, you wrote:
>
> Use existing macros (PAGE_MASK/PAGE_ALIGN()) instead of
> open-coding them.
>
> Signed-off-by: Dave Hansen <haveblue@us.ibm.com>
> ---
>
>  lxc-dave/fs/proc/task_mmu.c |    4 ++--
>  1 file changed, 2 insertions(+), 2 deletions(-)
>
> diff -puN fs/proc/task_mmu.c~pagemap-use-PAGE_MASK fs/proc/task_mmu.c
> --- lxc/fs/proc/task_mmu.c~pagemap-use-PAGE_MASK	2007-08-07 15:30:52.000000000 -0700
> +++ lxc-dave/fs/proc/task_mmu.c	2007-08-07 15:30:52.000000000 -0700
> @@ -669,9 +669,9 @@ static ssize_t pagemap_read(struct file 
>  		goto out;
>  
>  	ret = -ENOMEM;
> -	uaddr = (unsigned long)buf & ~(PAGE_SIZE-1);
> +	uaddr = (unsigned long)buf & PAGE_MASK;
>  	uend = (unsigned long)(buf + count);
> -	pagecount = (uend - uaddr + PAGE_SIZE-1) / PAGE_SIZE;
> +	pagecount = (uend - PAGE_ALIGN(uaddr)) / PAGE_SIZE;

Unless I'm missing something the PAGE_ALIGN as ist stands is now a NOP
because uaddr is already page aligned. You probably wanted to
PAGE_ALIGN(uend). However, this will likely add an additional instruction
to the generated code.

    regards  Christian



^ permalink raw reply	[flat|nested] 4+ messages in thread

* Re: [RFC][PATCH 2/5] pagemap: use PAGE_MASK/PAGE_ALIGN()
  2007-08-08  7:38   ` [RFC][PATCH 2/5] pagemap: use PAGE_MASK/PAGE_ALIGN() Christian Ehrhardt
@ 2007-08-08 15:11     ` Dave Hansen
  0 siblings, 0 replies; 4+ messages in thread
From: Dave Hansen @ 2007-08-08 15:11 UTC (permalink / raw)
  To: Christian Ehrhardt; +Cc: linux-kernel, serue

On Wed, 2007-08-08 at 09:38 +0200, Christian Ehrhardt wrote:
> 
> >       ret = -ENOMEM;
> > -     uaddr = (unsigned long)buf & ~(PAGE_SIZE-1);
> > +     uaddr = (unsigned long)buf & PAGE_MASK;
> >       uend = (unsigned long)(buf + count);
> > -     pagecount = (uend - uaddr + PAGE_SIZE-1) / PAGE_SIZE;
> > +     pagecount = (uend - PAGE_ALIGN(uaddr)) / PAGE_SIZE;
> 
> Unless I'm missing something the PAGE_ALIGN as ist stands is now a NOP
> because uaddr is already page aligned. You probably wanted to
> PAGE_ALIGN(uend). However, this will likely add an additional instruction
> to the generated code. 

Yeah, I aligned the wrong thing.  I'll fix that up.

-- Dave


^ permalink raw reply	[flat|nested] 4+ messages in thread

end of thread, other threads:[~2007-08-08 15:11 UTC | newest]

Thread overview: 4+ messages (download: mbox.gz follow: Atom feed
-- links below jump to the message on this page --
     [not found] <8PFSA-6mt-3@gated-at.bofh.it>
     [not found] ` <8PFSA-6mt-1@gated-at.bofh.it>
2007-08-08  7:38   ` [RFC][PATCH 2/5] pagemap: use PAGE_MASK/PAGE_ALIGN() Christian Ehrhardt
2007-08-08 15:11     ` Dave Hansen
2007-08-07 22:33 [RFC][PATCH 1/5] pagemap: remove file header Dave Hansen
2007-08-07 22:33 ` [RFC][PATCH 2/5] pagemap: use PAGE_MASK/PAGE_ALIGN() Dave Hansen
2007-08-08  1:54   ` Matt Mackall

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