[REPOST PATCH] kexec: Remove the unnecessary conditional judgement to simplify the code logic

[REPOST PATCH] kexec: Remove the unnecessary conditional judgement to simplify the code logic

[Minfei Huang]

Transforming PFN(Page Frame Number) to struct page is never failure, so
we can simplify the code logic to do the image->control_page assignment
directly in the loop, and remove the unnecessary conditional judgement.

Signed-off-by: Minfei Huang <mnfhuang@gmail.com>
Acked-by: Dave Young <dyoung@redhat.com>
Acked-by: Vivek Goyal <vgoyal@redhat.com>
---
 kernel/kexec.c | 3 +--
 1 file changed, 1 insertion(+), 2 deletions(-)

diff --git a/kernel/kexec.c b/kernel/kexec.c
index 6f1ed75..cf82474 100644
--- a/kernel/kexec.c
+++ b/kernel/kexec.c
@@ -807,11 +807,10 @@ static struct page *kimage_alloc_crash_control_pages(struct kimage *image,
 		/* If I don't overlap any segments I have found my hole! */
 		if (i == image->nr_segments) {
 			pages = pfn_to_page(hole_start >> PAGE_SHIFT);
+			image->control_page = hole_end;
 			break;
 		}
 	}
-	if (pages)
-		image->control_page = hole_end;
 
 	return pages;
 }
-- 
2.4.0

Re: [REPOST PATCH] kexec: Remove the unnecessary conditional judgement to simplify the code logic

[Simon Horman]

On Tue, Jul 28, 2015 at 12:46:42PM +0800, Minfei Huang wrote:
> Transforming PFN(Page Frame Number) to struct page is never failure, so
> we can simplify the code logic to do the image->control_page assignment
> directly in the loop, and remove the unnecessary conditional judgement.
> 
> Signed-off-by: Minfei Huang <mnfhuang@gmail.com>
> Acked-by: Dave Young <dyoung@redhat.com>
> Acked-by: Vivek Goyal <vgoyal@redhat.com>

Andrew, could you consider picking this up.
It seems to have been sufficiently reviewed, acked, etc...

> ---
>  kernel/kexec.c | 3 +--
>  1 file changed, 1 insertion(+), 2 deletions(-)
> 
> diff --git a/kernel/kexec.c b/kernel/kexec.c
> index 6f1ed75..cf82474 100644
> --- a/kernel/kexec.c
> +++ b/kernel/kexec.c
> @@ -807,11 +807,10 @@ static struct page *kimage_alloc_crash_control_pages(struct kimage *image,
>  		/* If I don't overlap any segments I have found my hole! */
>  		if (i == image->nr_segments) {
>  			pages = pfn_to_page(hole_start >> PAGE_SHIFT);
> +			image->control_page = hole_end;
>  			break;
>  		}
>  	}
> -	if (pages)
> -		image->control_page = hole_end;
>  
>  	return pages;
>  }
> -- 
> 2.4.0
> 
> 
> _______________________________________________
> kexec mailing list
> kexec@lists.infradead.org
> http://lists.infradead.org/mailman/listinfo/kexec
> 

Re: [REPOST PATCH] kexec: Remove the unnecessary conditional judgement to simplify the code logic

[Baoquan He]

On 08/13/15 at 09:55am, Simon Horman wrote:
> On Tue, Jul 28, 2015 at 12:46:42PM +0800, Minfei Huang wrote:
> > Transforming PFN(Page Frame Number) to struct page is never failure, so
> > we can simplify the code logic to do the image->control_page assignment
> > directly in the loop, and remove the unnecessary conditional judgement.
> > 
> > Signed-off-by: Minfei Huang <mnfhuang@gmail.com>
> > Acked-by: Dave Young <dyoung@redhat.com>
> > Acked-by: Vivek Goyal <vgoyal@redhat.com>
> 
> Andrew, could you consider picking this up.
> It seems to have been sufficiently reviewed, acked, etc...

I saw this has been in linux-next tree.

commit b90b6ef0f152ef42fe66ce5c9ccf2783ea84fa69
Author: Minfei Huang <mnfhuang@gmail.com>
Date:   Thu Jul 30 09:56:18 2015 +1000

    kexec: remove unnecessary test in kimage_alloc_crash_control_pages()

Thanks
Baoquan

Re: [REPOST PATCH] kexec: Remove the unnecessary conditional judgement to simplify the code logic

[Simon Horman]

On Thu, Aug 13, 2015 at 01:53:45PM +0800, Baoquan He wrote:
> On 08/13/15 at 09:55am, Simon Horman wrote:
> > On Tue, Jul 28, 2015 at 12:46:42PM +0800, Minfei Huang wrote:
> > > Transforming PFN(Page Frame Number) to struct page is never failure, so
> > > we can simplify the code logic to do the image->control_page assignment
> > > directly in the loop, and remove the unnecessary conditional judgement.
> > > 
> > > Signed-off-by: Minfei Huang <mnfhuang@gmail.com>
> > > Acked-by: Dave Young <dyoung@redhat.com>
> > > Acked-by: Vivek Goyal <vgoyal@redhat.com>
> > 
> > Andrew, could you consider picking this up.
> > It seems to have been sufficiently reviewed, acked, etc...
> 
> I saw this has been in linux-next tree.

Excellent, sorry for the noise.

> commit b90b6ef0f152ef42fe66ce5c9ccf2783ea84fa69
> Author: Minfei Huang <mnfhuang@gmail.com>
> Date:   Thu Jul 30 09:56:18 2015 +1000
> 
>     kexec: remove unnecessary test in kimage_alloc_crash_control_pages()
> 
> Thanks
> Baoquan
> 

Re: [REPOST PATCH] kexec: Remove the unnecessary conditional judgement to simplify the code logic

[Andrew Morton]

On Thu, 13 Aug 2015 09:55:25 +0900 Simon Horman <horms@verge.net.au> wrote:

> On Tue, Jul 28, 2015 at 12:46:42PM +0800, Minfei Huang wrote:
> > Transforming PFN(Page Frame Number) to struct page is never failure, so
> > we can simplify the code logic to do the image->control_page assignment
> > directly in the loop, and remove the unnecessary conditional judgement.
> > 
> > Signed-off-by: Minfei Huang <mnfhuang@gmail.com>
> > Acked-by: Dave Young <dyoung@redhat.com>
> > Acked-by: Vivek Goyal <vgoyal@redhat.com>
> 
> Andrew, could you consider picking this up.
> It seems to have been sufficiently reviewed, acked, etc...

I grabbed this one of July 28. 
http://ozlabs.org/~akpm/mmotm/broken-out/kexec-remove-the-unnecessary-conditional-judgement-to-simplify-the-code-logic.patch